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Objective:To observe the expression patterns of miR-195 and DLL4 in colorectal cancer, and to explore the relationship between miR-195 and DLL4 and clinicopathological parameters and prognosis of patients with colorectal cancer.Methods:The relative expression of miR-195 in 56 colorectal cancer tissues was detected by real-time fluorescent quantitative PCR the expression of DLL4 protein and tumor microvessel density (MVD) were detected by bloting and immunohistochemistry. Colon cancer cell line SW480 was treated with miR-195. The expression of DLL4, Jagged1, (the intracellular domain of notch, NICD), CyclinD1, Hes1, Bcl-2 and NF-kB were detected by bloting.Results:The expression level of DLL4 protein in colorectal cancer tissues was significantly higher than that in normal intestinal mucosa (30/56 vs.16/56, t=5.323, P=0.018). The expression level of miR-195 was significantly lower than that in normal intestinal mucosa (36/56 vs.20/56, t=2.371, P=0.008). The expression of DLL4 was negatively correlated with the expression of miR-195 ( r=- 0.881, P=0.015) , which was closely related to the differentiation degree, lymph node metastasis and TNM stage . The prognosis of patients with high expression of DLL4 was significantly worse than that with low expression of DLL4 ( P=0.013). The prognosis of patients with low expression of miR-195 was worse than that with high expression of miR-195 ( P=0.009) . Conclusion:The antagonistic expression of miR-195 and Notch might be closely related to the occurrence and development of colorectal cancer, which can be used as a new reference index for prognosis of colorectal cancer.
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Objective:To investigate whether ventricular non-excitatory electrical stimulation(NES)preconditioning can protect myocardial ischemia-reperfusion(IR)injury in aged mice by regulating cardiac calcitonin gene-related peptide(CGRP).Methods:Male C57BL/6J mice were randomly divided into 3 groups, (1)the Sham group, receiving sham operation group(n=6); (2)the IR group, receiving ligation of coronary artery to induce myocardial ischemia for 45 min and reperfusion for 120 min(n=13); (3)the NES group, IR model receiving NES from 15 min before IR to the end of reperfusion(n=13). Infarct size was detected by staining with 2, 3, 5-triphenyltetrazolium chloride.The level of serum cTnI and expression of myocardial CGRP were measured by enzyme linked immunosorbent assay and quantitative real time polymerase chain reaction.Results:Compared with the IR group, the infarct sizes were significantly lower in NES group[(38.17±4.36)% vs.(45.33±5.68)%, P<0.05]. Besides, the IR and NES groups were associated with significantly increased levels of serum cTnI[(10.89±2.14)μg/L, (7.03±1.79)μg/L vs.(3.92±0.47)μg/L, P<0.001], myocardial CGRP protein[(26.33±4.55)μg/kg, (19.67±5.79)μg/kg vs.(17.00±2.90)μg/kg, P<0.01], CGRP mRNA[(1.40±0.20), (2.20±0.75) vs.(1.05±0.10), P<0.01]compared with the Sham group.Furthermore, the NES group was associated with markedly decreased levels of serum cTnI and myocardial CGRP protein, and increased level of CGRP mRNA compared with the IR group(all P<0.05). Conclusion:NES may protect myocardium IR injury by regulating endogenous CGRP expression in aged mice.
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Objective@#To investigate the protective effects of pretreatment with a Shenfu(SF)injection on arrhythmias induced by myocardial ischemia-reperfusion(IR)injury in aged mice.@*Methods@#Thirty 18-month-old C57BL/6J mice were randomly divided into 3 groups(n=10, each group): the sham treatment group(receiving sham operation without thoracotomy), the IR group(undergoing the ligation of the left anterior descending coronary artery with ischemia for 30 min and reperfusion for 2 h)and the SF group(receiving SF intraperitoneal injection of 10 ml/kg 30 min before thoracotomy and the same treatment as the IR group). Arrhythmias were monitored, and serum levels of creatine kinase-isoenzyme(CK-MB), troponin(cTnI)and tumor necrosis factor α(TNFα), and the ratio of myocardial connexin 43(Cx43)phosphorylation(ser368)to total protein(p-Cx43/t-Cx43)were detected in the three groups.@*Results@#Ventricular arrhythmias occurred in the IR and SF groups.Compared with the IR group, ventricular arrhythmias in the SF group were alleviated, the frequency of ventricular premature systolic episodes was reduced(36.6±13.5 times vs. 48.4±22.1 times), the frequency of ventricular tachycardia/fibrillation decreased(3.4±1.8 times vs. 7.6±3.5 times), and the total duration of ventricular tachycardia/fibrillation episodes was shortened(8.9±4.5 times vs. 17.7±5.1 times)in the SF group(P<0.05), but there was no significant difference in arrhythmia scores(1.8±1.2 points vs. 1.9±1.7 points, P>0.05)between the two groups.Compared with the sham treatment group, serum levels of CK-MB, cTnI and myocardial TNF(increased in the IR and SF groups(P<0.05), and their levels were lower in the SF group than in the IR group(P<0.05). Compared with the sham treatment group, the ratio of Cx43 ser368/total protein was lower in the IR and SF groups, but was higher in the SF group than in the IR group(P<0.05).@*Conclusions@#SF pretreatment can significantly reduce IR-induced arrhythmias in aged mice possibly by reducing TNF(and up-regulating the phosphorylation activity of Cx43.
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Objective To investigate the protective effects of pretreatment with a Shenfu(SF) injection on arrhythmias induced by myocardial ischemia-reperfusion(IR)injury in aged mice.Methods Thirty 18-month-old C57BL/6J mice were randomly divided into 3 groups (n=10,each group):the sham treatment group(receiving sham operation without thoracotomy),the IR group (undergoing the ligation of the left anterior descending coronary artery with ischemia for 30 min and reperfusion for 2 h)and the SF group(receiving SF intraperitoneal injection of 10 ml/kg 30 min before thoracotomy and the same treatment as the IR group).Arrhythmias were monitored,and serum levels of creatine kinase-isoenzyme (CK-MB),troponin (cTnI) and tumor necrosis factor α (TNFα),and the ratio of myocardial connexin 43 (Cx43) phosphorylation (ser368) to total protein (p-Cx43/t-Cx43) were detected in the three groups.Results Ventricular arrhythmias occurred in the IR and SF groups.Compared with the IR group,ventricular arrhythmias in the SF group were alleviated,the frequency of ventricular premature systolic episodes was reduced(36.6 ± 13.5 times vs.48.4 ± 22.1 times),the frequency of ventricular tachycardia/fibrillation decreased(3.4 ± 1.8 times vs.7.6 ± 3.5 times),and the total duration of ventricular tachycardia/fibrillation episodes was shortened(8.9± 4.5 times vs.17.7± 5.1 times)in the SF group(P＜0.05),but there was no significant difference in arrhythmia scores(1.8± 1.2 points vs.1.9 ± 1.7 points,P ＞0.05) between the two groups.Compared with the sham treatment group,serum levels of CK-MB,cTnI and myocardial TNF(increased in the IR and SF groups (P ＜ 0.05),and their levels were lower in the SF group than in the IR group (P＜0.05).Compared with the sham treatment group,the ratio of Cx43 ser368/total protein was lower in the IR and SF groups,but was higher in the SF group than in the IR group(P＜0.05).Conclusions SF pretreatment can significantly reduce IR-induced arrhythmias in aged mice possibly by reducing TNF(and up-regulating the phosphorylation activity of Cx43.
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Objective To evaluate the role of transient receptor potential vanillic acid subtype 1 (TRPV1)/calcitonin gene-related peptide (CGRP) signaling pathway in lidocaine postconditioning-induced reduction of myocardial ischemia-reperfusion (I/R) injury in rats.Methods Forty healthy male SpragueDawley rats,aged 3 months,weighing 250-300 g,were divided into 5 groups (n=8 each) using a random number table method:sham operation group (group Sham),group I/R,lidocaine postconditioning group (group LP),lidocaine postconditioning plus CGRP8-37 group (group LP+CGRP8-37),and lidocaine postconditioning plus capsazepine group (group LP+Capz).Myocardial ischemia was induced by ligating the anterior descending branch of left coronary artery for 30 min,followed by 120-min repeRFusion in anesthetized rats.Lidocaine 2 mg/kg was injected via the tail vein at 5 min before reperfusion in group LP.In group LP + CGRP8-37,lidocaine was intravenously injected,and CGRP receptor selective antagonist CGRP8-37 2 mg/kg was intravenously injected at the same time.In group LP+Capz,lidocaine was injected intravenously,and TRPV1 blocker capsazepine 3 mg/kg was injected intravenously at the same time.A catheter was retrogradely implanted to the left ventricle,and heart rate (HR),left ventricular systolic pressure (LVSP),left ventricular end-diastolic pressure (LVEDP),and the maximum rate of increase or decrease in left ventricular pressure (±dp/dtmax) were continuously monitored and recorded.Blood samples were collected from the carotid artery at 120 min of reperfusion for determination of cardiac troponin I (cTnI),myoglobin (Myo) and creatine kinase-MB (CK-MB) concentrations in serum.Rats were then sacrificed for determination of myocardial infarct size.Results Compared with Sham group,the serum concentrations of cTnI,Myo and CK-MB were significantly increased,LVSP,+dP/dtmax and HR were decreased,and LVEDP and-dP/dtmax were increased in I/R group and LP group (P＜0.05).Compared with group I/R,the serum concentrations of cTnI,Myo and CK-MB and myocardial infarct size were significantly decreased,LVSP and +dP/dtmax were increased,and LVEDP,-dP/dtmax and HR were decreased in group LP (P＜0.05),and no significant change was found in the parameters mentioned above in group LP+ CGRP8-37 and group LP+Capz (P＞0.05).Compared with group LP,the serum concentrations of cTnI and Myo,myocardial infarct size and LVEDP were significantly increased,and + dP/dtmax was decreased in group LP+CGRP8-37,and the serum concentrations of cTnI and Myo and myocardial infarct size were significantly increased,LVSP and +dP/dtmax were decreased,and LVEDP was increased in group I/R+Lido+Capz (P＜0.05).Conclusion The mechanism by which lidocaine postconditioning mitigates myocardial I/R injury is related to activating TRPV1/CGRP signaling pathway in rats.
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Objective To evaluate the application effect of psychological intervention of husband and wife for the center to patients with in vitro fertilization and embryo transfer. Methods Eighty infertile couples with in vitro fertilization and embryo transfer were selected and divided into intervention group and control group with 40 cases in each group according to the document order numbers, the two groups were given conventional health education of in vitro fertilization and embryo transfer, in addition,the patients in the intervention group received psychological intervention of husband and wife for the center, the intervention time was 5 weeks. Questionnaire investigation about Self- rating Depression Scale (SDS), Self- rating Anxiety Scale (SAS),Coping Style Scale and Subjective Feeling of Marriage Scale were conducted before and after the intervention. Results The scores of SDS and SAS were (30.43±8.92), (33.48±9.92) points after the intervention in the intervention group, and (40.26±9.54), (41.51±7.24) points in the control group,and there were significant differences (t=7.611, 6.245, P<0.01).The scores of help seeking, self- accusation, fantasy, wince and rationalization in Coping Style Scale were (0.63±0.19), (0.25±0.21), (0.41±0.22), (0.43±0.24), (0.42±0.21) points after the intervention in the intervention group, and (0.51±0.21), (0.38±0.22), (0.51±0.19), (0.55±0.23), (0.55±0.22) points in the control group, and there were significant differences(t=3.008-3.668, P < 0.05). The scores of subjective feelings of marriage and family relationship were (64.79±9.75), (34.37±5.12) points after inntervention in the intervention group, and (58.09±11.42), (29.23±4.97) points in the control group, and there were significant differences (t=7.212, 3.463, 15.234, P < 0.05). Conclusions Applying psychological intervention of husband and wife for the center to patients with in vitro fertilization and embryo transfer can improve the psychological state, reduce depression and anxiety, adopt positive coping style, increase the quality of marriage.
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Objective To detect the expressions of enhancer of zeste homology 2 (EZH2) and signal transducer and activator of transcription 3 (STAT3) in gastric cancer tissues,and analyze the relationship between their expressions and clinicopathological factors and prognosis of patients.Methods The clinical data of 67 patients with gastric cancer who were admitted to the People's Hospital of Peking University from May 1999 to April 2000 were retrospectively analyzed.Gastric cancer tissues and adjacent normal tissues were harvested and fixed in 4％ formaldehyde,and then to make the tissue chips.The protein expressions of EZH2 and STAT3 were detected by immunohistochemical staining,and the relationship between the expressions of EZH2 and STAT3 and the prognosis of patients was analyzed.The correlation between the protein expressions of EZH2 and STAT3 in the gastric and colorectal tissues and the clinicopathological parameters was analyzed using the paired chi-square test.The survival curve was drawn by Kaplan-Meier method,and the survival rate was analyzed by using the Logrank test.The relationship between the clinicopathological factors and the prognosis of patients was analyzed using the COX proportional hazard model.Results The positive protein expression rates of EZH2 and STAT3 in the gastric cancer tissues were 73.1％ (49/67) and 67.2％ (45/67),which were significantly higher than 32.8％ (22/67) and 37.3％ (25/67) in the adjacent normal tissues (x2=21.839,11.964,P ＜0.05).The protein expression of STAT3 was correlated with the age,TNM staging,lymph node metastatic status (x2=5.475,9.998,5.475,P ＜ 0.05).The protein expression of EZH2 was correlated with TNM staging and lymph node metastatic status (x2=11.573,5.902,P ＜ 0.05).The co-expression rate of EZH2 and STAT3 proteins was 73.1％ (49/67),EZH2 and STAT3 had the common expression trend (r =0.397,P ＜ 0.05).The co-expression rate of EZH2 and STAT3 was increased as the increase of TNM stages,and the co-expression of EZH2 and STAT3 in the gastric cancer tissue was correlated with the TNM stages (x2 =6.997,P ＜ 0.05).The 5-year survival rate of patients with low protein expression of EZH2 was significantly higher than those with high protein expression of EZH2 (x2=7.386,P ＜ 0.05).The 5-year survival rate of patients with low proteins expression of STAT3 was significantly higher than those with high proteins expression of STAT3 (x2=12.253,P ＜ 0.05).The 5-year survival rate of patients with low co-expression of EZH2 and STAT3 protein was significantly higher than those with high co-expression of EZH2 and STAT3 proteins (x2 =8.765,P ＜ 0.05).The results of univariate analysis showed that age,TNM staging,EZH2 and STAT3 expression,lymph node metastasis and distal metastasis were the factors influencing the survival of patients with gastric cancer (RR =2.136,3.452,3.179,8.341,11.773,6.873,P ＜0.05).The results of multivariate analysis showed that TNM staging and STAT3 expression were independent factors influencing the prognosis of patients with gastric cancer (RR =2.453,7.535,P ＜ 0.05).Conclusions There is significant correlation between EZH2 and STAT3 protein expressions in gastric cancer tissues,and co-expression of EZH2 and STAT3 is associated with the TNM staging and the prognosis of the patients with gastric cancer.
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Objective To explore protein expression and significance of MAGE genes in colorectal carcinoma(CRC)tissues.Methods The expression of MAGE genes were studied by using tissue chip and immunochemistry methods in primary CRC tissue and paired adjacent tissue samples in 97 cases.Data were analyzed with x2-test by SPSS 16.0 software.Results The protein expression of MAGE-A3,MAGE-A4 and MAGE-A10 genes were 57％(56/97),63％(61/97)and 28％(27/97)respectively in 97 cases of primary adenocarcinoma.The protein expression frequency of MAGE-A3 in poor colorectal adenocarcinomas was significantly higher than in well-and moderately disfferentiated adenocarcinomas(x2 =9.133,P =0.010).MAGE-A10 in poor colorectal primary adenocarcinomas was significantly higher than in well and moderately adenocarcinomas(x2 =15.280,P =0.000); MAGE-A10 protein expression was significantly higher in stage TNM Ⅲ + Ⅳ than in stage TNM Ⅰ + Ⅱ(x2 =4.227,P=0.040); MAGE-A10 gene expression was higher in metastasis lymphoid node than in no metastasis lymphoid node(x2 =5.557,P =0.018),and the expression level was higher in primary lesion with the increasing of the numbers of lymphoid node metastasis(x2 =7.296,P =0.026).Conclusions The protein expression of MAGE genes is associated with the tumor differentiation,TNM stage and lymphoid node metastasis.MAGE-A3 and MAGE-A10 genes are the possible prognosis marker and potential target of immunotherapy of CRC.
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<p><b>OBJECTIVE</b>To study the influence of Aconiti Lateralis Radix Praeparata on asthenia cold syndrome rats with whole genome gene expression of liver by gene chip technique.</p><p><b>METHOD</b>The asthenia cold syndrome rat models were established by administering traditional Chinese medicine raw Gypsum Fibrosum, Gentianae Radix, Phellodendri Chinensis Cortex and Anemarrhenae Rhizoma. After treated with Aconiti Lateralis Radix Praeparata, the rats' liver gene expressions were detected using gene chip. Differential expression genes were screened for gene function annotation, and some genes were selected to check the accuracy of the results by RT-PCR.</p><p><b>RESULT</b>Compared with the asthenia cold model group, the asthenia cold treatment group showed 212 differential expression genes, mainly involving function of immune response and oxidoreductase activity.</p><p><b>CONCLUSION</b>Aconiti Lateralis Radix Praeparata is proved to have an effect on up-regulating immune response-related genes and oxidizing oxidoreductase activity-related genes of asthenia cold syndrome rats and may be a molecular mechanism for classical warm-nature medicine Aconiti Lateralis Radix Praeparata in warming meridians and dissipating cold.</p>
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Animals , Female , Male , Rats , Aconitum , Chemistry , Asthenia , Drug Therapy , Genetics , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Gene Expression Profiling , Genomics , Liver , Metabolism , Oligonucleotide Array Sequence Analysis , Rats, WistarABSTRACT
Objective To explore the protein expression of PLAC1/CP1 ( cancer-placenta 1 ) and its correlation with clinicopathological characteristics in patients of colorectal carcinoma. Methods The expression of PLAC1/CP1 gene was studied by using tissue chip and immunochemistry in 125 cases CRC tissue specimens. Data were analyzed with the x2-test or Fisher's x2 test statistic by SPSS 16. 0 software.Results The protein expression of PLAC1/CP1 gene was 57.6% (72/125) in 125 cases of CRC and 56. 7% (55/97)in 97 primary adenocarcinoma cases. That was 78. 9% (15/19)in poor differentiated colorectal primary adenocarcinoma, those were significantly higher than that of 35.3% (6/17) in well and 55.7% (34/61) in moderately differentiated adenocarcinoma ( P ＜ 0.05 ); PLAC1/CP1 protein expression was significantly higher in stage TNM Ⅲ + Ⅳ 71.2% (37/52) than in stage TNM Ⅰ + Ⅱ 40% (18/45)(P ＜ 0.05 ); PLAC1/CP1 genes expression rate was 69.6% (32/46) in these with lymphoid node metastasis and 45.1% (23/51)in patients without lymphoid node metastasis (P ＜ 0.05 ). The positive expression rate of PLAC1/CP1 increased in colorectal carcinoma with the increasing of the numbers of lymphoid node involved with metastasis( x2 = 13. 353, P = 0.001 ). Conclusions The protein expression of PLAC1/CP1 is associated with tumor differentiation, TNM stage and lymphoid node metastasis.
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Objective To evaluate the correlation between regional blood perfusion,metabolism and angiogenesis in breast cancer.Methods The PET/CT functional imaging technique was applied to quantitatively detect the central and marginal blood perfusion parameters including blood flow(BF),blood volume(BV)and permeability of surface(Ps),and metabolism index of standard uptake value(SUV)of the tumor in 33 breast cancer patients.The expression of CD31.CD105 and VEGF in paraffin section of breast cancer were detected by immunohistochemical method,then MVD(CD31)and MVD(CD105)were obtained.The relationship between the regional blood perfusion and metabolism and MVD(CD3 1),MVD(CD105)and the expression of VEGF were analyzed. Results There was significant correlation of MVD (CD31)with BF of marginal region(P<0.05).There were significant correlations of MVD(CD105)with BF.PS and SUV(P<0.05). Conclusions Regional blood perfusion,metabolism is correlated with angiogenesis in breast cancer tissue.PETT/CT regional blood perfusion and metabolic imaging iS a noninvasive method which can be used to estimate angiogenesis status clinically in breast cancer.
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0.05),after six weeks remission rates were 84.6% and 30.0%,respectively(P 0.05).Conclusions Interventional stent placement is recommended for patients with external compression IVC obstruction,with significant relief of the clinical symptoms and prolongation of the survival term.For embolic type of IVC obstruction patients,stenting is only a short-term palliative modality because of higher re-obstruction rate and shorter survival term.
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Aptamers are oligo-nucleotides which are selected by SELEX (systematic evolution of ligands by exponential enrichment) in vitro, it can bind protein or other small molecules with high specificity and affinity. Researches on aptamers have achieved much progress in biosensor, drug development and nano technology. This article has reviewed the researches and applications of aptamers in the past two years.
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Animals , Humans , Aptamers, Nucleotide , Biosensing Techniques , Methods , Drug Design , Nanotechnology , Methods , SELEX Aptamer TechniqueABSTRACT
Objective: To explore the feasible methods for item selection of TCM syndrome scale.Methods:Elderly hypertension with syndrome of kidney qi deficiency was selected as example.The symptoms and signs of elderly hypertension patients were statistically analyzed with clinical epidemiological investigation on the basis of discussion among focus group and expert consultation.Six selection methods were used,such as correlation coefficient method,dispersion tendency method,factor analysis method,etc.Results:18 Items were selected in the end and constituted the preliminary scale of kidney qi deficiency of elderly hypertension.Conclusion:Only if combine subjective and objective selection methods,use kinds of proper statistical methods and master the scale of preserving items,can we acquire good reliability and validity of scale.
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OBJECTIVE： To compare the quality of ceftazidime for injection among the domestic and imported products METHODS： The ceftazidime was observed and determined with respect to the property， color and clarity of the solution， insoluble particle， content of pyridine， polymer of ceftazidime and marked content of ceftazidime RESULTS： There were some differences in above－ mentioned parameters among products of different factories， however， the parameters were within the range of standard CONCLUSION： The quality of domestic products is reliable and comparable to that of imported ones
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Objective To evaluate clinical effects of endovascular angioplasty and stenting for treating lower extremity arteriosclerotic occlusion(ASO).Methods After the identification of the stenosis or occlusion by angiography via femoral artery access by percutaneous puncture or incision puncture,recanalization of the occlusion was done by ultrasound ablation or guildewire clearance.Then the percutaneous transluminal angioplasty(PTA) was performed and an endovascular stent was introduced.Results A total of 45 cases(53 legs) had undergone endovascular angioplasty and stenting.The procedure was technically successful in all the patients.The ankle brachial index(ABI) increased from 0.36?0.14 preoperatively to 0.77?0.21 on the 7 postoperative day((t=2.397),P=0.021).Follow-up checkups in all the cases for 6~54 months(mean,23 months) revealed a primary patency rate of 90.6%(48/53).Conclusions Endovascular angioplasty and stenting is a safe and effective method for treating lower extremity arteriosclerotic occlusion.
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Objective To evaluate the use of PET/CT in the diagnosis of breast cancer. Methods In this study,33 patients with suspicious breast tumor underwent PET/CT imaging. The images of the breast were analyzed for qualitative assessment of increased tracer uptake and blood perfusion with PET/CT. Results Among 27 cases with pathology proved breast cancer,25 was judged as PET/CT positive,2 was false-negative. Sensitivity, specificity and accuracy of PET/CT in identifying breast cancer were 92.6%,100%,93.9%. Conclusion PET/CT is a reliable and sensitive measure in the diagnosis of breast cancer in vivo.
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Purpose: To evaluate the antiemetic effect of azasetron hydrochloride in patients with liver neoplasm after transcatheter arterial chemoembolization. Methods: 62 patients (33 with primary hepatocellular carcinoma and 29 with hepatic metastasis), who underwent transcatheter arterial chemoembolization( TACE) therapy 78 times in all, were allocated into the azasetron group( administration of azasetron hydrochloride) and the control group( administration of metoclopramide) randomly. The inhibitory effects on nausea and vomiting were observed in the two groups respectively. Results: The antiemetic CR ratio and the response rate( CR + PR) in the azasetron group was 81.0% and 99. 7%, respectively. These results were statistically higher than those in the control group( P
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0.05). Conclusions In comparison with mammography,PET/CT has a higher degree of sensitivity and specificily in detecting breast cancer,and higher positive predictive value.PET/CT can provide more aspects of in vivo diagnostic information which may be useful in selecting therapeutic strategy and may supplement the inadequacies of mammography.
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Objective To develop and charaterize a series of Poloxamer-and Carbopol-based in situ gel for ophthalmic use as to enhance the ability of drug to retain in eyes and delay drug release.Methods The gel was prepared using Poloxamer 407/188 and Carbopol 974P as gelling agent and viscosity enhancer,respectively.Rheological characteristics were evaluated and behaviour of drug release in vitro was investigated by modified Franz diffusion cells.Results The rheological study indicated that the gel was physically entangled polymer solutions at 20 ℃ and then converted into a network structure with secondary bonds at 35 ℃.The gel released the drug molecules slowly in 4 h.The best fit model was Higuchi matrix model(r=0.992 3).Formulations consisting of Poloxamer 188 and Carbopol 974P were proved to be able to decrease the drug release speed efficiently.The impact on elastic modulus G" of the gel caused by those two were different.Conclusion An in situ gel with suitable sol-gel transition temperature and satisfactory release pattern could be achieved by adjusting the ratio of Poloxamer 407 to Poloxamer 188.The developed formulations have the ability to prolong the ocular residence time,which suggests it may be a new durg delivery system with bright future.