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BackgroundThe pathogenesis of depression remains not fully understood， and previous studies have suggested that the kynurenine pathway （KP） plays an important role in the pathogenesis of major depressive disorder. ObjectiveTo study the difference in serum KP metabolites level between patients with first-episode and recurrent major depressive disorder， and to testify the correlation between KP metabolites level with the severity of depressive symptoms， so as to provide references for the prevention of recurrence. MethodsA total of 136 patients with major depressive disorder who attended the outpatient clinics of the Affiliated Brain Hospital of Guangzhou Medical University from November 2016 to December 2018 and met the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders， fifth edition （DSM-5） diagnostic criteria were included， including 62 patients in the first-episode group and 74 patients in the recurrent group. Meanwhile， 60 healthy subjects were included as control group. All patients were assessed by Hamilton Depression Scale-17 item （HAMD-17）， and serum concentrations of tryptophan （TRP）， kynurenine （KYN） and kynurenic acid （KYNA） were measured by liquid chromatography tandem mass spectrometry （LC-MS/MS）. Then the correlation of HAMD-17 total score and individual item scores with the levels of KP metabolites was tested using partial correlation coefficient. ResultsCompared with the control group， the first-episode group and recurrent group showed a marked decline in TRP concentration （t=-3.044， -4.477， P<0.05 or 0.01） and an increase in KYN/TRP ratio （t=2.343， 3.644， P<0.05 or 0.01）， with significant differences. The KYNA concentrations （t=2.490， 2.636， P<0.05 or 0.01） and KYNA/KYN ratio （t=2.894， 2.616， P<0.01） in first-episode group and control group were notably elevated compared to recurrent group， with statistical difference. Partial correlation analysis in patients with first-episode major depressive disorder demonstrated that KYN/TRP ratio was positively correlated with the HAMD-17 anxiety/somatization factor score （r=0.261， P<0.05）， and KYNA/KYN ratio was negatively correlated with HAMD-17 total score and block factor score （r=-0.286， -0.282， P<0.05）. In patients with recurrent major depressive disorder， KYN/TRP ratio was positively correlated with HAMD-17 anxiety/somatization factor score （r=0.280， P<0.05）. ConclusionKP metabolites in serum differ between first-episode and recurrent major depressive disorder patients， and patients with recurrent episodes experience severe KP metabolite abnormalities. Therefore， KP metabolites are considered to be potential biomarker candidates to assist clinicians in the diagnosis and recurrent prediction of major depressive disorder. ［Funded by National Key Research and Development Program Precision Medicine Research Project （number， 2016YFC0906300）］
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Objective:To evaluate the diagnostic efficiency of contrast-enhanced magnetic resonance angiography (CE-MRA), T 1WI and three-dimensional thin-layer T 1WI sequences (3D-T 1WI) in evaluating the blood supply of brain tumors, so as to improve the enhanced magnetic resonance imaging (MRI) scanning scheme of brain tumors. Methods:After the contrast agent was injected, 29 patients with brain tumors were scanned with CE-MRA, T 1WI and 3D-T 1WI. The imaging manifestations of " observing the enhancement of tumor substance" , " observing the small vessels in the tumor body" and " observing the small vessels around the tumor" were qualitatively classified, and the diagnostic differences of the three sequences were analyzed by McNemar test. Results:⑴ In the aspect of " observing the contrast medium in the tumor body" , CE-MRA, T 1WI and 3D-T 1WI sequences diagnosed as grade A1 were 0 cases, 8 cases (27.59%) and 19 cases (65.52%) respectively. The diagnostic efficiency of 3D-T 1WI sequences was better than that of T 1WI sequence ( P<0.05), and T 1WI sequence was better than that of CE-MRA sequence ( P<0.05). ⑵ In the aspect of " observing the small vessels in the tumor" , CE-MRA, T 1WI and 3D-T 1WI sequences diagnosed as grade B1 were 8 cases (27.59%), 5 cases (17.24%) and 16 cases (55.17%), respectively. The diagnostic efficiency of 3D-T 1WI was better than that of T 1WI and CE-MRA ( P<0.05). ⑶ In the aspect of " observing the small vessels around the tumor" , CE-MRA, T 1WI and 3D-T 1WI sequences diagnosed as grade C1 were 18 cases(62.07%), 5 cases (17.24%) and 14 cases (48.28%) respectively. The diagnostic efficiency of CE-MRA and 3D-T 1WI wre better than that of T 1WI ( P<0.05). Conclusions:The combination of 3D-T 1WI and CE-MRA sequence can comprehensively evaluate the blood supply of the tumor, which is of great significance for the localization, characterization and treatment of brain tumors.
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Objective To investigate the effects of particle size, wind speed and dumping velocity on aerosol concentration distribution during powder dumping in a reprocessing plant. Methods CeO2 powder was selected as the substitute material of PuO2. FLUENT software was used to calculate the pouring process of CeO2 powder under different operation conditions. Then the aerosol concentration distribution under different dumping speeds was measured by particle size spectrometer to verify the accuracy of simulation results. Results The particles with small particle size are more likely to be separated from the mainstream area by the drag force of the surrounding gas, and the radius of the diffusion range also increases with the decrease of the particle size. 2) When the ventilation speed is less than 1 m/s, the dust lifting can be reduced and the concentration of dust particles in the chamber can be reduced to a certain extent. 3) In the process of powder dumping, the spoon is rotated anticlockwise at a speed of 100° in 2～3 s, and less dust aerosol is produced on the right side of the tray. Conclusion When operating the powder particles with smaller particle size, more attention should be paid to the monitoring of aerosol at different positions; the change of air inlet velocity makes the flow field in glove box more complex, and the volume fraction of dust particles is related to the size and location of vortex formed by airflow. The greater the wind speed, the greater the impact on the powder dumping process. The experimental results are basically consistent with the simulation results, and the results show that the lower the dumping speed, the smaller the aerosol concentration near the tray.
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ObjectiveTo explore the anhedonia level and its relationship with cognitive function in patients with first-episode psychosis， and to analyze the influencing factors of cognitive function. MethodsA total of 143 first-episode psychiatric patients who met the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders， fifth edition （DSM-5） in the Affiliated Brain Hospital of Guangzhou Medical University from December 2016 to March 2019 were selected. Positive and Negative Syndrome Scale （PANSS） was used to evaluate the patient’s psychiatric symptoms， in which N2 （emotional withdrawal） and N4 （passive/apathetic social withdrawal） were used to assess the anhedonia level， and patients whose （N2+N4） scores beyond 4 were classified into anhedonia group， and those with （N2+N4） scores less than or equal to 4 were classified into non-anhedonia group. Hamilton Depression Scale-24 item （HAMD-24） was used to measure the depressive symptoms， and the MATRICS Consensus Cognitive Battery （MCCB） was used to detect cognitive function. Then the clinical symptoms and cognitive function of two groups were compared， and the influencing factors of cognitive function were screened by multiple linear regression analysis. ResultsThe negative symptom score， general pathological symptom score and total score of PANSS in anhedonia group were significantly higher than those of non-anhedonia group， with statistical difference （P<0.05）. The score of working memory in adolescent subgroup， the scores of information processing speed， attention/alertness and vocabulary learning in adult subgroup of anhedonia group were lower than those of non-anhedonia group， with statistical difference （P<0.05）. Multiple linear regression analysis showed that the anhedonia score and the duration of untreated psychosis were the influencing factors of working memory in adolescent subgroup （P<0.05）. ConclusionPatients with high levels of anhedonia suffer more severe mental symptoms and cognitive impairment， moreover， anhedonia is one of the influencing factors of working memory in adolescents.
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ObjectiveTo explore the differences of cognitive function in patients with treatment-resistant depression and drug-naive first-episode major depressive disorder， and to examine the relationship between severity of clinical symptoms and cognitive function， so as to provide references for prognosis improvement. MethodsFrom November 2016 to December 2019， 119 patients with drug-naive first-episode major depressive disorder and 82 patients with treatment-resistant depression in a hospital in Guangzhou were enrolled， meantime， another 71 healthy individuals recruited from the community were set as healthy control group. Clinical symptoms were assessed using Hamilton Depression Scale-17 item （HAMD-17） and Hamilton Anxiety Scale （HAMA）. Cognitive domains， including speed of processing， working memory， verbal learning and memory， and visual learning and memory were measured with the MATRICS Consensus Cognitive Battery （MCCB）. Multiple covariance analysis was used to compare the differences in cognitive function among three groups. Thereafter， partial correlation analysis was performed within patient groups to explore the relationship of HAMD-17/HAMA score with the four dimensions of MCCB. ResultsThe speed of processing， visual learning and memory scores of treatment-resistant depression group and drug-naive first-episode depression group were lower than those of healthy control group， and the working memory score of the treatment-resistant depression group was lower than that of the healthy control group， with statistical significance （P<0.05 or 0.01）. The speed of processing， visual learning and memory scores of treatment-resistant depression group were significantly lower than those of drug-naive first-episode depression group （P<0.05 or 0.01）. Partial correlation analysis within patient groups found that HAMD-17/HAMA total score had no correlation with the four dimensions of MCCB （P>0.05）. ConclusionCompared with drug-naive first-episode major depressive disorder patients and healthy controls， the impairments of speed of processing， visual learning and memory are more severe in patients with treatment-resistant depression. Moreover， the cognitive function impairment in patients with drug-naive first-episode major depressive disorder and treatment-resistant depression has no correlation with the severity of depressive and anxious symptoms.
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Objective To explore social function of long-term hospitalized patients with stable schizophrenia and its influential factors to provide scientific evidence for improving social function in long-term hospitalized patients with schizophrenia. Methods A total of 75 long-term hospitalized patients with stable schizophrenia were enrolled. The Social Functional Rating Scale (SFRS), Positive and Negative Syndrome Scale (PANSS), Insight and Treatment Attitude Questionnaire (ITAQ), Rating Scale for Extrapyramdal Side Effects (RSESE) and MATRICS (Measurement and Treatment Research to Improve Cognition in Schizophrenia) Consensus Cognitive Battery (MCCB) were used to assess social function, clinical symptoms and cognitive function of patients. Bivariate correlation analysis and linear regression were used to examine the correlations between social function and clinical symptoms as well as cognitive function. Results The average score of SFRS was (53.6 ±9.3). Linear regression analysis showed that negative symptom of PANSS (B= 0.322, P=0.009), speed of processing (B=-0.428, P<0.001), working memory (B=-0.191, P=0.020)and RESES (B=0.918, P=0.002) were significantly associated with social function. The Sobel test showed significant indirect effects between negative symptom and social function, which were significantly mediated by working memory (Z=3.367, P<0.001) and speed of processing (Z=1.995, P=0.046). Conclusion Social function of long-term hospitalized patients with stable schizophrenia is influenced by negative symptom, speed of processing, working memory and extrapyramdal side effects. There is a mediating effect between PANSS negative symptoms and SFRS in working memory and processing speed.
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Objective To investigate the effect of reducing antipsychotic dose on clinical symptoms in patients with stable schizophrenia. Methods Seventy-five patients with stable schizophrenia taking olanzapine or risperidone were enrolled. Patients were randomly divided into dose reduction group (37 cases) and maintenance group (38 cases). The dose of the risperidone or olanzapine was gradually reduced by 50％ in the dose reduction group within six months whereas remained unchanged in the maintenance group. The Positive and Negative Symptom Scale (PANSS), Calgary Depression Scale (CDRS), Personal and Social Performance Scale (PSP), Insight and Treatment Attitude Questionnaire (ITAQ) and Extrapyramidal Side Effects Scale (RSESE) were assessed at baseline, 3 months, 6 months and 12 months. Results There were one and two cases dropped out due to the relapse in dose reduction group and in maintenance group, respectively. The recurrence rates were 2.7％ in dose reduction group and 5.3％ in maintenance group (P<0.05). The interaction effects of PANSS positive symptoms, negative symptoms and general pathological symptoms, ITAQ,RSESE, PSP were significant (P<0.05). The main effect of PANSS negative symptoms and PSP group was significant (P<0.05). Compared with the maintenance group, PANSS negative symptoms of the dose reduction group were significantly lower at 6 and 12 months (P<0.05). PSP scores were significantly higher in the dose reduction group than in maintenance group (P<0.05) at 3, 6 and 12 months. Conclusion Reducing the dose of risperidone or olanzapine slowly in patients with stable schizophrenia within six months reduces negative symptoms and adverse reaction, improves social function without increasing positive symptoms.
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Objective To investigate the CT imaging features of urinary tract ceftriaxone-associated pseudolithiasis.Methods The CT imaging data of three patients with ceftriaxone-associated pseudolithiasis were collected from August,2008 to April,2012.Their data combined with related literatures were used to review CT imaging features of urinary tract pseudolithiasis.Those three patients,including 2 males and 1 female,were 9,21 and 55 years old,respectively.Ceftriaxone sodium was administrated to one patient due to appendicitis and the other two patients due to urinary tract infection.After ceftriaxone treatment,1 case began to have backache and abdominal pain on day 13,1 case presented backache with floc in the urine on day 2 and progressed to anuria,and the other one had cotton-like material in the urine on day 5.Urinary tract high density shadows were found in all patients by CT scan.The patient with anuria was treated with ureteroscopic lithotripsy and percutaneous nephrolithotomy.The other 2 cases were arranged to be followed up with CT scan.In those cases,the CT showed that the high density shadow in one patient disappeared 16 days after drug discontinuation.The high density shadow was significantly reduced 12 days after ceftriaxone withdrawal in the other one.However,no follow-up was performed afterwards.Results All the urinary tract ceftriaxone-associated pseudolithiasis presented the high density shadows on CT,with CT value 47-667 HU.The density of CT results is homogenic,except one ureteral stone.The pseudolithiasis,existed in kidney,ureter and bladder simultaneously,were found in two patients.And the other patient was found that the pseudolithiasis existed in both kidney and bladder.Two cases were accompanied with hydroureter and hydronephrosis and the other case were accompanied with cholecystolithiasis.The multiple renal pseudolithiasis was noticed in 2 cases,which exhibited the nodular shape.And one patient with hydronephrosis presented both sand-like and nodular stones.Ureteral pseudolithiasis was found in 1 case with 4 stones and the other one with 2 stones.In those pseudolithiasis,5 appeared column morphology and one showed nodular shape.The single nodular stone in bladder was found in one case.And the multiple bladder stones were found in 2 cases.Conclusions The CT imaging characters of urinary tract ceftriaxone-associated pseudolithiasis are high homogenic density shadows in multiple parts of bilateral urinary tracts.The ceftriaxone-associated pseudolithiasis is column shape in ureter and sand-like or nodular shape in kidney and bladder.
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Objective To analyze the impact factors and their importance on academic reputation of medical research institutions in China.Methods Seventy medical researchers and 70 medical graduate students were selected by convenience sampling method.Brainstorming and expert consultation were applied to determine the 6 factors affecting the academic reputation of medical research institutions in China.A Face-to-face or e-mail interview was conducted using a designed questionnaire.Six affecting factors were nominated analyzed.Chi-square test was used to cross exam nominated rate and affecting factors;Bonferroni method was also applied to make paired comparisons.Results There is significant difference in nomination rates among 6 impact factors (P ＜ 0.001).Pairwise comparison showed that information obtained by academic exchange (70.49 ％) and the scientific understanding generated from research practice (67.21％) are top 2 impact factors to the medical research institutions;followed by all kinds of ranking list (44.26％),and the celebrity effect (42.62％).Conclusions Scientific communication and research practice are two most important factors affecting the academic reputation of medical research institutions in China.
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Objective:To establish a method for the content uniformity ( CU) of fennel oil in Weitongning tablets to study the CU of fennel oil in Weitongning tablets. Methods: Methyl salicylate as the internal reference, the content of trans-anethole in fennel oil was determined by GC. The separation was performed on a DB-FFAP capillary column (30 m × 0. 32 mm, 0. 25 μm) at 145℃, the injection part temperature was 180℃ and the FID detector temperature was 230℃, nitrogen with high purity was used as the carrier gas at the flow rate of 0. 8 ml·min-1 . The air flow rate was 400 ml·min-1 and that of hydrogen was 35 ml·min-1 . The methodology validation was carried out, and the samples from different companies with different batches were determined. Results:Significant differ-ence showed in the CU of fennel oil in the samples with different batches from the same manufacturer or from different companies. The trans-anethole showed linear correlation within the range of 2. 189-35. 030 μg · ml-1 ( r =0. 999 9 ) and the average recovery was 100. 06% (RSD=0. 5%, n=9). Conclusion:The method is simple and quick. It is accurate in the CU determination of fennel oil and can be used for the quality control of Weitongning tablets.
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Objective To take the imaging anatomy and measurement of facial nerve canal for cochlear implantation patients,and to provide the reference for how to avoid the injury of facial nerve in the opreration.Methods 35 patients which would be given to cochlear implantation were taken 128 thin-slice CT scan preoperative,then using multi planar reformation (MPR) and curved planar reformation (CPR) techniques,the three-dimensional reconstruction were carried out,and referring the facial nerve anatomy of posterior tympanic facial recess approachartificial cochlear implantation,the relationship between the vertical segnent of facial nerve canal and facial recess,tympanic cavity structure was key displayed.The facial nerve canal sections in temporal bone were measured,and compared with measurement results of 35 cases of cochlear implant patients.Results 35 patients underwent 128-slice CT scan three-dimensional reconstruction of MPR and CPR techniques,the facial nerve segment was clearly displayed,and its vertical section of the posterior wall of the external auditory canal,facial recess distance was (3.31 + 0.88)mm,(1.89 + 0.29) mm,respectively,and the vertical segment of the facial nerve canal wall,the facial recess distance of intraoperative measurement was (3.22 + 0.69) mm,(1.85 + 0.26) mm,respectively,and there were.no significant difference between the the both results(all P ＞ 0.05).35 patients had no case of face paralysis.Conclusion 128-slice spiral CT thin scan combined with MPR and CPR techniques can understand the facial nerve canal and surrounding anatomical landmarks of the fine relationship,measurable facial nerve canal length,and provide basis for how to avoid facial nerve injury in the cochlear implant,temporal bone,and the other side of the skull base surgery.
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<p><b>OBJECTIVE</b>To investigate the relationship between fractional anisotropy (FA) and somatosensory evoked potentials (SEP) in the postcentral gyrus subcortex in patients with acute infarction of the posterior limb of the internal capsule.</p><p><b>METHODS</b>Thirty-one patients with acute infarction of the posterior limb of the internal capsule underwent diffusion tensor imaging to obtain the FA values of the subcortical region of the postcentral gyrus with manual placement of the regions of interest (ROI). SEP and the sensory functions of the patients were examined and graded.</p><p><b>RESULTS</b>In each SEP grade group, the FA values of the subcortical region of the postcentral gyrus were significantly decreased on the diseased side compared to those of the normal side (P<0.05). The FA values of the diseased side differed significantly between patients with different SEP grades (P<0.05), and increased SEP abnormalities were associated with lowered FA values. The sensory function of the patients was positively correlated to the grade of SEP (r=0.520, P<0.05).</p><p><b>CONCLUSION</b>For patients with acute infarction of the posterior limb of the internal capsule, the changes of FA in the postcentral gyrus subcortex on the diseased side are correlated and complementary to SEP in evaluating the prognosis.</p>
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Aged , Female , Humans , Male , Middle Aged , Anisotropy , Brain Infarction , Pathology , Brain Mapping , Diffusion Magnetic Resonance Imaging , Evoked Potentials, Somatosensory , Internal Capsule , PathologyABSTRACT
Objective To investigate the changing characteristics of the fractional anisotropy (FA) in cerebral peduncles and its relation with motor evoked potential (MEP) after acute cerebral infarction and to clear the clinical sigiificance of the low limit value of the FA in cerebral peduncles. Methods The low limit value of the FA in normal cerebral peduncles was determined based on mean - 1. 64 standard deviation. The patients with acute cerebral infarction (n = 58) were divided into MEP positive group and MEP negative group according to the absence and presence of MEP, in which the patients in the MEP positive group were redivided into the FA in cerebral peduncles ＜ the low limit value and≥ the low limit value groups according to the FA in cerebral peduncles on the affected sides. Results The low limit value of the FA in normal cerebral peduncles was 0. 36. There was significant difference in the FA in cerebral peduncles on the affected sides between the MEP negtive and MEP positive groups. The MEP negative group was the lowest (P=0. 000). The FA in cerebral peduncles on the affected sides in the positive group was significantly lower than that on the unaffected sides (P=0. 000), and the latency on the affected sides was longer than that on the normal sides (P=0. 000). The FA in cerebral peduncles on the affected sides was negatively correlated with the MEP latency (r=-0.332,P=0. 042). The MEP latency in the FA＜the low limit value group was significantly longer than that in the FA ≥ low limit value group (P=0. 002). There were no significant differences in the FA in cerebral peduncles on the normal sides and the MEP latency among an groups. The detection rate of the FA in cerebral peduncle＜0. 36 on the affected sides was the highest (50%). Conclusions In the evaluation of the prognosis of the patients, the changes of the FA in cerebral peduncles on the affected sides in patients with acute cerebral infarction had correlation,consistency, and complementarity with MEP.The detection rate of the low limit value of the FA in normal cerebral peduncles was the highest in the MEP negative patients. When the FA in cerebral peduncles was＜0.36 on the affected sides, particularly when MET was negative, it might predict that the prognosis was poor.
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Objective To evaluate the diagnostic value of physical examination,digital mammography and color Dopplor ultrasonography for breast masses.Methods The materials of clinic,digital mammography and color Dopplor ultrasonogrpahy(US)in 92 women(raged from 18～80 years old in age,with average of 49.8 years old)with breast masses confirmed by pathology were retrospectively analysed,including benign in 43 and malignant in 49.Digital mammographic findings including the location,shape,margins,calcifications and the lymph node of axillary of the breast lesions,and color Dopplor ultrasonographic findings including mainly the characteristics of lesions on two-dimensional sonography,the distribution of the internal and peripheral vessels of the lesions were observed,the physical examination mainly observed the skin and nipple,and the margins,texture and movement of the lesions.Results In diagnosing breast masses,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy were 85.71%,79.07%,82.35%,82.93% and 82.61%,respectively with digital mammography,79.59%,83,72%,84.78%,78.26% and 81.52%,respectively with US,71.42%,76.74%,77.78%,70.21%,73.91%,respectively with physical examination,while were 91.84%,93.02%,93.75%,93.3% and 90.91%,respectively in combination with three methods,which were significantly higher than that of each single examination(P＜0.05),but there were no differences between each examination(P＞0.05).Conclusion It can improve the diagnosing accuracy of breast masses by suitable combination of three of digital mammography,color Dopplor ultrasonography and physical examination.
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Objective To present the clinical effect of dorsal carpometacarpal island flap with fascia, vessel and nerve to repair soft tissue defected. Methods The island flap was designed with root of fascia, dorsal metalcarpals artery and nerve.The flap to soft tissue defected in the nearby area was applied, including 30 cases in the last segment of thumb, 4 cases in the first segment of thumb, 1 case in the IP articulation of thumb, 1 case in the first segment of middle finger, 1 case in the carpometacarpal dorsal area and 1 case in the back of index finger. Results Thirty-eight cases were survived. All cases obtained good appearance and sensory recovery approach normally with little affection in supply area. Conclusions This method has advantage of simple, practical, high survive rate, low impairment, sensible and good appearance.
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Objective: To study the curative effects of Rupixiao Grains on mammary hyperplasia rats and provide the bisis for the wider use. Methods: The model of mammary hyperplasia were established with estrogen and progestogen, the changes of nipple appearance and pathological tissue of mammary gland on morphologic change were observed. The E2, P and PRL of serum were determined. Results: The treatment groups of high and middle dose of Rupixiao Grains can siginifi cantly reduce the diameter and height of nipple in rat mammary gland hyperplasia models(P
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0.05). Conclusion Comparedwith DSA and operation,there is excellent correlation among 3D contrast-enhanced moving-bed MRA,DSA and operation.MRA canaccurately and entirely assess occlusive disease of the arteries of the lower extremity.It is a ono-invasive,reliable and potential newtechnique.
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Objective To study the neurogenesis of the dentate gyrus(DG) and the expression of the doublecortin(DCX) in the hippocampus of the rat whose spatial learning and memory function was enhanced by chronic multiple stress. Methods Adult male Wistar rats were randomly divided into two groups: multiple stressed group and control group.Rats in the multiple stressed group were irregularly and alternatively exposed to the chronic multiple stress for 6 weeks.After that,all rats were tested for the performance of spatial learning and memory in Morris water maze.The number of newborn neurons in the DG was counted by using immunocytochemical method.The expression of the DCX protein and the level of DCX mRNA in the hippocampus of rats were measured by using Western blotting and RT-PCR technique,respectively. Results The results showed that: 1.Compared with the ones of the control group,the multiple stressed rats had a significantly shorter latent period to search the platform in Morris water maze(P