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1.
Journal of Forensic Medicine ; (6): 573-578, 2022.
Artigo em Inglês | WPRIM | ID: wpr-984148

RESUMO

OBJECTIVES@#To analyze and predict the striking velocity range of stick blunt instruments in different populations, and to provide basic data for the biomechanical analysis of blunt force injuries in forensic identification.@*METHODS@#Based on the Photron FASTCAM SA3 high-speed camera, Photron FASTCAM Viewer 4.0 and SPSS 26.0 software, the tester's maximum striking velocity of stick blunt instruments and related factors were calculated and analyzed, and inputed to the backpropagation (BP) neural network for training. The trained and verified BP neural network was used as the prediction model.@*RESULTS@#A total of 180 cases were tested and 470 pieces of data were measured. The maximum striking velocity range was 11.30-35.99 m/s. Among them, there were 122 female data, the maximum striking velocity range was 11.63-29.14 m/s; there were 348 male data, the maximum striking velocity range was 20.11-35.99 m/s. The maximum striking velocity of stick blunt instruments increased with the increase of weight and height, but there was no obvious increase trend in the male group; the maximum striking velocity decreased with age, but there was no obvious downward trend in the female group. The maximum striking velocity of stick blunt instruments has no significant correlation with the material and strike posture. The root mean square error (RMSE), the mean absolute error (MAE) and the coefficient of determination (R2) of the prediction results by using BP neural network were 2.16, 1.63 and 0.92, respectively.@*CONCLUSIONS@#The prediction model of BP neural network can meet the demand of predicting the maximum striking velocity of different populations.


Assuntos
Masculino , Humanos , Feminino , Redes Neurais de Computação , Software , Ferimentos não Penetrantes , Medicina Legal
2.
Journal of Forensic Medicine ; (6): 452-458, 2022.
Artigo em Inglês | WPRIM | ID: wpr-984135

RESUMO

OBJECTIVES@#To reconstruct the cases of acceleration craniocerebral injury caused by blunt in forensic cases by finite element method (FEM), and to study the biomechanical mechanism and quantitative evaluation method of blunt craniocerebral injury.@*METHODS@#Based on the established and validated finite element head model of Chinese people, the finite element model of common injury tool was established with reference to practical cases in the forensic identification, and the blunt craniocerebral injury cases were reconstructed by simulation software. The cases were evaluated quantitatively by analyzing the biomechanical parameters such as intracranial pressure, von Mises stress and the maximum principal strain of brain tissue.@*RESULTS@#In case 1, when the left temporal parietal was hit with a round wooden stick for the first time, the maximum intracranial pressure was 359 kPa; the maximum von Mises stress of brain tissue was 3.03 kPa at the left temporal parietal; the maximum principal strain of brain tissue was 0.016 at the left temporal parietal. When the right temporal was hit with a square wooden stick for the second time, the maximum intracranial pressure was 890 kPa; the maximum von Mises stress of brain tissue was 14.79 kPa at the bottom of right temporal lobe; the maximum principal strain of brain tissue was 0.103 at the bottom of the right temporal lobe. The linear fractures occurred at the right temporal parietal skull and the right middle cranial fossa. In case 2, when the forehead and left temporal parietal were hit with a round wooden stick, the maximum intracranial pressure was 370 kPa and 1 241 kPa respectively, the maximum von Mises stress of brain tissue was 3.66 kPa and 26.73 kPa respectively at the frontal lobe and left temporal parietal lobe, and the maximum principal strain of brain tissue was 0.021 and 0.116 respectively at the frontal lobe and left temporal parietal lobe. The linear fracture occurred at the left posterior skull of the coronary suture. The damage evaluation indicators of the simulation results of the two cases exceeded their damage threshold, and the predicted craniocerebral injury sites and fractures were basically consistent with the results of the autopsy.@*CONCLUSIONS@#The FEM can quantitatively evaluate the degree of blunt craniocerebral injury. The FEM combined with traditional method will become a powerful tool in forensic craniocerebral injury identification and will also become an effective means to realize the visualization of forensic evidence in court.


Assuntos
Humanos , Análise de Elementos Finitos , Fenômenos Biomecânicos , Ferimentos não Penetrantes , Cabeça , Traumatismos Craniocerebrais
3.
Chinese Medical Sciences Journal ; (4): 210-217, 2021.
Artigo em Inglês | WPRIM | ID: wpr-921871

RESUMO

Objective We developed a universal lesion detector (ULDor) which showed good performance in in-lab experiments. The study aims to evaluate the performance and its ability to generalize in clinical setting via both external and internal validation. Methods The ULDor system consists of a convolutional neural network (CNN) trained on around 80K lesion annotations from about 12K CT studies in the DeepLesion dataset and 5 other public organ-specific datasets. During the validation process, the test sets include two parts: the external validation dataset which was comprised of 164 sets of non-contrasted chest and upper abdomen CT scans from a comprehensive hospital, and the internal validation dataset which was comprised of 187 sets of low-dose helical CT scans from the National Lung Screening Trial (NLST). We ran the model on the two test sets to output lesion detection. Three board-certified radiologists read the CT scans and verified the detection results of ULDor. We used positive predictive value (PPV) and sensitivity to evaluate the performance of the model in detecting space-occupying lesions at all extra-pulmonary organs visualized on CT images, including liver, kidney, pancreas, adrenal, spleen, esophagus, thyroid, lymph nodes, body wall, thoracic spine,


Assuntos
Simulação por Computador , Computadores , Redes Neurais de Computação , Tomografia Computadorizada por Raios X
4.
Journal of Medical Postgraduates ; (12): 968-972, 2019.
Artigo em Chinês | WPRIM | ID: wpr-818357

RESUMO

Objective The main cause of systemic inflammatory response syndrome(SIRS) after percutaneous nephrolithotomy(PCNL) was still unclear. The purpose of this study was to investigate the risk factors associated with SIRS after PCNL and establish the nomogram model. Methods A retrospective analysis of 213 cases of PCNL patients due to upper urinary calculi admitted to urology department in affiliated hospital of guilin medical college from December 2017 to December 2018 was performed. According to the occurrence of SIRS, patients were divided into SIRS group (SIRS patients) and control group (patients without SIRS). Logistic regression was used to analyze the risk factors of SIRS after PCNL, and a nomogram model was established based on logistic regression model. Results There were 54 cases in the SIRS group and 159 in the control group. Gender(OR=2.547, 95%cl:1.229-5.275), diabetes (OR=5.027, 95%cl: 1.442-17.525), calculi surface area (OR=2.657, 95%cl: 1.206-5.853), NLR immediately after surgery (OR=3.793, 95%cl: 1.749-8.02), operation time (OR=2.985, 95%cl: 1.305-6.826), and blood transfusion (OR=12.50, 95%cl: 12.50). 1.954-80.056) were the risk factors of SIRS after PCNL (P<0.05). Based on the results of the logistic multi-factor regression model mentioned above, visualized display of the model was achieved by using column and diagram. As the NLR ratio, operation time and stone surface area increased immediately after the operation, the score gradually increased, and the risk of SIRS gradually increased. The nomogram model established according to logistic regression model has good differentiation and model consistency (c-index =0.791). Conclusion According to the risk factors, such as gender, diabetes history, stone surface area, immediate postoperative NLR, the constructed nomogram model has good predictive efficacy, which is of guiding significance for clinical practice.

5.
China Journal of Endoscopy ; (12): 30-34, 2017.
Artigo em Chinês | WPRIM | ID: wpr-613535

RESUMO

Objective To evaluate the effect of modified bowel preparation-Polyethylene Glycol Electrolytes Powder (SF-PEG, Shu Taiqing) in combination with magnesium sulfate in patients with constipation undergoing colonoscopy. Methods Sixty cases from mild to moderate constipation were randomly divided into two groups:Group A: SF-PEG (438.4 g, 4 L), 30 cases; Group B: received low-dose SF-PEG (219.2 g, 2 L) and 50.00%magnesium sulfate 50 ml, and then 250 ml water, 30 cases. Boston Bowel Preparation Scale scores (BBPS) and bubbles in bowel lumen score were assessed by the same endoscopist blindly to the preparation regimen, and the time of colonoscopy and the tolerability was recorded. Results All patients underwent completely the bowel preparation and colonoscopy. The time of colonoscopy of group B was shorter than that of group A (P 0.05). Conclusion SF-PEG in combination with magnesium sulfate in patients with constipation for colonoscopy can improve tolerance to bowel preparation, cleanliness and effects of examination. It's safe to be recommended in clinical practice.

6.
Chinese Journal of Medical Genetics ; (6): 755-758, 2017.
Artigo em Chinês | WPRIM | ID: wpr-344181

RESUMO

<p><b>OBJECTIVE</b>To identify a rare subtype of the ABO blood group system and explore its molecular basis.</p><p><b>METHODS</b>Based on a standard serological assay, ABO subtype and haplotype were analyzed through PCR amplification of the 7 exons and adjacent introns of the ABO gene and TA clone sequencing.</p><p><b>RESULTS</b>Forward typing showed a B type, while reverse typing demonstrated an extremely weak anti-B on routine gel analysis, which indicated a forward and reverse typing discrepancy. Absorption-elution testing confirmed that there was no A antigen on the surface of patient's red blood cells. Sequencing of the ABO gene showed a G>A exchange at position 523 in exon 7, which resulted in a Val to Met substitution at codon 175. Clone sequencing of the amplificons of the ABO gene showed an ABO* Bw14/O01 heterozygote genotype.</p><p><b>CONCLUSION</b>Molecular method is useful for the identification of ambiguous blood groups. A 523G>A substitution of the ABO gene resulting in a Bw14 subtype probably underlies the weak B phenotype noted in the patient.</p>


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Sistema ABO de Grupos Sanguíneos , Genética , Éxons , Genótipo , Fenótipo , Reação em Cadeia da Polimerase
7.
Journal of Medical Biomechanics ; (6): E095-E101, 2016.
Artigo em Chinês | WPRIM | ID: wpr-804011

RESUMO

Objective To predict biomechanical responses of neck injuries under different loading conditions based on the finite element model of the 6-year-old pediatric neck. Methods The finite element model of the 6-year-old pediatric neck with real anatomical structural muscles was developed, according to the CT images. The model was verified by reconstructing the dynamic tensile test of different cervical spine segments, the tensile test of full cervical spine and the low speed impact experiment of the pediatric volunteers. Results The force-displacement curves, obtained from the simulations on tensile test of different cervical spine segments and tensile test of full cervical spine, were in good agreement with the experimental curves. The head angular velocity-time curve obtained from simulations on pediatric volunteer was consistent with the corridor obtained from experimental data. Conclusions The model is validated and can be used for studying the biomechanical responses and injury mechanism of pediatric neck under different loading conditions.

8.
Journal of Clinical Hepatology ; (12): 933-937, 2016.
Artigo em Chinês | WPRIM | ID: wpr-778639

RESUMO

ObjectiveTo investigate the mechanism of α-naphthyl isothiocyanate (ANIT) inducing cholestatic hepatitis. MethodsA total of 60 healthy male Sprague-Dawley rats were randomly divided into normal control group (N group with 30 rats) and model group (ANIT group with 30 rats), and each group was further divided into three subgroups according to different time phases after gavage (at 24, 48, and 72 hours after gavage), with 10 rats in each group. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), and total bilirubin (TBil) were measured, and the level of malondialdehyde (MDA) in the liver was measured. A light microscope was used to observe the pathological changes in the liver, and a transmission electron microscope was used to observe the changes in the ultrastructure of the bile canaliculus. A confocal laser scanning microscope was used to analyze the mean fluorescence intensity of phalloidine labeled by fluorescein isothiocyanate in order to determine the change in the level of fibrous actin (F-actin). ResultsAfter the administration of ANIT by gavage, the model group showed significant increases in the serum levels of ALT, AST, GGT, and TBil and the level of MDA in liver tissue compared with the normal control group. The model group also showed damage in the structure of the hepatic lobules, hyaline degeneration of hepatocytes, spotted, patchy, and focal necrotic lesions, and neutrophil infiltration mostly confined to the hepatocytes around the bile duct, proliferation of biliary epithelial and fibrous tissues, widened perisinusoidal spaces, dilation of the bile canaliculi, extensive shedding of microvilli, and formation of bile thrombi in the bile capillaries, as well as a low fluorescence intensity of F-actin. The above changes were the most obvious at 48 hours; recovery began at 72 hours, but significant differences were still seen between the two groups. ConclusionANIT can cause lipid peroxidation in liver tissue and lead to degeneration and necrosis of liver cells, damage of microvilli of the bile canaliculi, and formation of bile thrombi, as well as reduction in the expression of F-actin in the bile canaliculi. Therefore, it affects the function of the liver to secrete bile and causes cholestatic hepatitis.

9.
Chinese Journal of Internal Medicine ; (12): 345-348, 2016.
Artigo em Chinês | WPRIM | ID: wpr-488797

RESUMO

Objective To investigate the correlation between serum uric acid (SUA) level and early-phase insulin secretion in subjects with normal glucose regulation (NGR).Methods Totally 367 community NGR residents confirmed by a 75g oral glucose tolerance test were enrolled.The insulin resistance index (HOMA-IR) and the early-phase insulin secretion index after a glucose load (ΔI30/ΔG30) were used to estimate the insulin sensitivity and the early-phase insulin secretion, respectively.The subjects were divided into 4 groups according to the SUA level quartiles.Differences in early-phase insulin levels, ΔI30/ΔG30, and HOMA-IR were compared among the 4 groups.Results Age, BMI, waist circumference, systolic blood pressure, diastolic blood pressure, fasting insulin (FINS), 30 minutes postprandial insulin (30 minINS), 2 hours postprandial insulin(2hlNS), HOMA-IR and TG levels increased across the rising categories of SUA levels, while the HDL-C was decreased across the SUA groups (P < 0.01).The SUA level was positively correlated with age (r =0.157, P < 0.01), BMI (r =0.262, P < 0.01), waist circumference(r =0.372, P < 0.01), systolic blood pressure (r =0.200, P < 0.01), diastolic blood pressure(r =0.254,P < 0.01) , 30 minutes postprandial plasma glucose(r =0.118 ,P =0.023), FINS(r =0.249, P < 0.01), 30minlNS (r =0.189, P < 0.01) ,2hlNS (r =0.206, P < 0.01), glycosylated hemoglobin (HbAlc, r=0.106,P =0.042), HOMA-IR(r =0.244,P <0.01), TG(r =0.350,P <0.01), ΔI30/ΔG30 (r =0.144, P < 0.01), and negatively correlated with HDL-C level (r =-0.321, P < 0.01).Multiple stepwise regression analysis showed that SUA (β =0.292, P < 0.01) and HOMA-IR (β3 =29.821, P < 0.01)were positively associated with ΔI30/ΔG30.Conclusion SUA level is closely related with the early-phase insulin secretion in NGR subjects.

10.
Journal of International Pharmaceutical Research ; (6): 817-821, 2013.
Artigo em Chinês | WPRIM | ID: wpr-845867

RESUMO

Objective To study n vitro antioxidant effects of Borojoa sorbilis Cuter. Method Concentrated solution of fresh fruits of B. sorbilis Cuter, as well as fractions which eluted through macroporous resin column, were taken as total sample, unabsorbed part, water part, 30% alcohol part and 60% alcohol part. Five samples were measured by three different in vitro tests: 2,2-diphenyl-l-picrylhydrazyl(DPPH) radical scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid(ABTS) radical scavenging activity and ferric reducing antioxidant power (FRAP). Ascorbic acid (Vc) was used as a positive control. The possible material basis of antioxidant activities was analyzed by LC-MS. Results Samples showed good DPPH radical scavenging effect, while ABTS radical scavenging effect and ferric reducing antioxidant power activity are not obvious. Ion peak clusters in the total ion chromatogram (TIC), the retention time at 4. 00-5. 00 min, may be nvolved n antioxidant activity. Conclusion B. sorbilis Cuter, has moderate antioxidant activity compared with Vc, and ts material basis may be related to the notable on peaks in TIC.

11.
Chinese Medical Journal ; (24): 2120-2125, 2012.
Artigo em Inglês | WPRIM | ID: wpr-244401

RESUMO

<p><b>BACKGROUND</b>Immune cells within a tumor microenvironment have shown modulatory effects on tumor angiogenic activity. Renal cell carcinoma (RCC) is a hypervascular tumor that reportedly increases the frequency of regulatory T cells (Tregs) in tumor tissues. This study investigated the correlation between Tregs infiltration and angiogenic status in RCC.</p><p><b>METHODS</b>Thirty-six patients with RCC were enrolled in the present study, and twenty age-matched healthy donors were included as the control. Tregs were defined as CD4(+)CD25(high)CD127(low/-) T cells. The frequency of Tregs in peripheral blood and tumor infiltrating lymphocytes (TILs) were determined by flow cytometry. The expression of vascular endothelial growth factor (VEGF) in surgical resection specimens were measured with a commercial enzyme-linked immunosorbent assay (ELISA) kit. Microvessel density (MVD) was calculated on slides stained with CD34 antibody. Spearman's rank correlation was performed to evaluate the correlation between the frequencies of Tregs in TILs and VEGF values, as well as between frequencies of Tregs and MVD determinations.</p><p><b>RESULTS</b>Compared to healthy controls, the frequency of peripheral blood Tregs was significantly increased in patients with RCC (P < 0.05). The percentage of tumor-infiltrating Tregs was higher than that of peripheral blood Tregs in patients with RCC (P < 0.01). In addition, the frequency of tumor-infiltrating Tregs was shown to significantly correlate with the pathological stage (P < 0.05) and nuclear grade (P < 0.01). Importantly, a significant positive correlation was observed between the frequency of tumor-infiltrating Tregs and VEGF protein expression (r = 0.51, P < 0.05), as well as between frequencies of Tregs and MVD score (r = 0.39, P < 0.05).</p><p><b>CONCLUSIONS</b>These observations suggest that the high pro-angiogenic status of RCC may be associated with the accumulation of Tregs in the local microenvironment. Angiogenesis networks may be connected with immune tolerance units and cooperate with each other to facilitate tumor growth and progression.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Renais , Alergia e Imunologia , Metabolismo , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imuno-Histoquímica , Neoplasias Renais , Alergia e Imunologia , Metabolismo , Linfócitos do Interstício Tumoral , Alergia e Imunologia , Neovascularização Patológica , Alergia e Imunologia , Metabolismo , Linfócitos T Reguladores , Alergia e Imunologia
12.
Chinese Journal of Bases and Clinics in General Surgery ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-543553

RESUMO

Objective To evaluate the advances in minimally invasive surgery treatment for hepatolithiasis. Methods Literatures about the advances in minimally invasive surgery treatment for hepatolithiasis were collected and reviewed. Results Hepatectomy and bile duct exploration using laparoscopy can get better effect. Fibrocholedochoscopy play an important role in the course of operation and after operation for hepatolithiasis. Conclusion The individualization treatment program should be used for hepatolithiasis. Association application of multipathway minimally invasive operation, such as laparoscopy, fibrocholedochoscopy and so on, can increase the cure rate of hepatolithiasis.

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