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51.
Cadavers remain a principal teaching tool for anatomists and medical educators teaching gross anatomy. Infectious pathogens in cadavers that present particular risks include Mycobacterium tuberculosis, hepatitis B and C, the AIDS virus HIV, and prions that cause transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease (CJD) and Gerstmann-Straussler-Scheinker syndrome (GSS). It is often claimed that fixatives are effective in inactivation of these agents. Unfortunately cadavers, even though they are fixed, may still pose infection hazards to those who handle them. Specific safety precautions are necessary to avoid accidental disease transmission from cadavers before and during dissection and to decontaminate the local environment afterward. In this brief review, we describe the infectious pathogens that can be detected in cadavers and suggest safety guidelines for the protection of all who handle cadavers against infectious hazards.  相似文献   
52.
Several age-related alterations occur at the cellular level in the immune system leading to a decrease in the immune response. The present study was designed to determine the effect of L-carnitine on impaired neutrophil functions of aged rats. For this reason, superoxide anion radical production, chemotaxis and phagocytic activity were studied in the neutrophils obtained from the peripheral blood of young and old rats. We orally gavaged L-carnitine (50 mg/kg b.w. per day) or control vehicle into young (2 months) and aged (24 months) rats for 30 consecutive days. The neutrophils of aged rats exhibited an increase in superoxide anion production and decline in phagocytosis and chemotaxis when compared with that in young rat neutrophils. Superoxide anion production in aged rats was significantly decreased by L-carnitine treatment which was accompanied with a significant enhancement of chemotactic and phagocytic activity being restored to control levels. These findings demonstrated that L-carnitine is capable of restoring the age-related changes of neutrophil functions.  相似文献   
53.
Jitter analysis in single fiber EMG (SFEMG) is usually done on-line during recording. However, this technique frequently prolongs the study and makes re-analysis impossible. We attempted to measure jitter with a high speed FM tape recorder and compare the results with the previously published values. SFEMG data, acquired with voluntary activation on extensor digitorum communis muscle of 25 healthy relatives of children with myasthenia gravis were retrospectively analyzed. Fiber density (FD) was estimated on-line. Five to 18 single fiber action potential (SFAP) pairs were studied in each subject. The wow of the tape recorder was 6 microseconds. Mean (SD) (upper 95th percentile) FD, individual jitter, highest jitter, mean jitter and interspike interval were 1.60 (0.18) (1.90), 25.30 (11.20) (57.00) microseconds, 31.24 (6.87) (47.00) microseconds, 25.08 (5.04) (43.00) microseconds, and 0.67 (0.11) (0.91) ms respectively. Mean jitter in the pooled SFAP pairs and mean MCD were found to be lower than the published values of the Ad Hoc Committee of the AAEM Special Interest Group on Single Fiber EMG. A high speed FM tape recorder can be reliably used for the off-line analysis of jitter.  相似文献   
54.
Adenosquamous carcinomas are rare malignant tumors of the pancreas and periampullary region. We present two cases of pancreatic and periampullary adenosquamous carcinoma with clinicopathologic, histo- and immunohistochemical findings. A 51-year-old and a 48-year-old man presented with right upper quadrant pain of three months duration and jaundice for two weeks. Both cases had an elevation of liver enzymes and CA 19-9. In the first case, computerized tomography showed a 3 cm-mass at the pancreatic head. In the second one, endoscopic retrograde choledocopancreatography (ERCP) revealed a mass at the ampulla Vateri localization. A pancreatoduodenectomy was performed for both cases. Gross pathologic examination displayed a solid, gray-white colored 4 cm-tumor at the pancreatic head and a solid, pink-white colored, 2 cm-tumor at the periampullary region bulging into the duodenal lumen. Microscopically, both tumors were composed of solid nests of squamous cells with pearl formation and mucin-containing glandular cells and diagnoses were adenosquamous carcinoma. Furthermore, histo- and immunohistochemical findings were consistent with microscopic diagnoses.  相似文献   
55.
人KIR2DL1-Ig融合蛋白在COS-7细胞的表达   总被引:1,自引:1,他引:1  
目的:获得人KIR2DL1分子(killer lg—like receptor 2DL1)胞外区与人IgG Fc段的融合蛋白。方法:从人外周血单个核细胞中提取总RNA,通过RT—PCR扩增编码KIR2DL1胞外段cDNA,经Nhe Ⅰ和BamH Ⅰ双酶切后,定向插入真核细胞表达载体CD51negl中。构建的重组真核表达载体CD51negl—KIR2DL1。经酶切分析和测序鉴定后,通过DEAE—dextran/ehloroquine法转染COS—7细胞:瞬时表达后,取培养上清液经亲和层析、ELISA、SDS—PAGE及Western印迹,鉴定融合蛋白的表达及其免疫学活性。结果:序列测定证实,该重组表达载体含有正确的KIR2DL1胞外区基因序列。重组真核表达载体CD5lnegl—KIR2DL1转染COS—7细胞后,ELISA法检测细胞培养上清中有融合蛋白的表达。SDS—PAGE结果显示,该融合蛋白的相对分子质量(Mc)约为73000。Western印迹结果证实,该蛋白能被特异性单克隆抗体(mAb)EB6所识别。结论:KIR2DL1—Ig融合蛋白表达载体成功构建并在COS—7细胞中获得功能性表达,为KIR2DL1的功能及其配体MHC的研究奠定了基础。  相似文献   
56.
The occurrence of P fimbriae in a total of 222 uropathogenic Escherichia coli (UPEC) strains was investigated. Out of the total, 31 (14%) were P fimbriated. Of 24 pyelonephritogenic E. coli strains, three (13%) with P fimbriae occurred in children with clinical pyelonephritis, and of 198 E. coli strains 29 (15%) occurred in children with cystitis. Prevalence of P fimbriae of E. coli strains was found to be quite similar in patients with cystitis and pyelonephritis  相似文献   
57.
Situated on mature B lymphocytes, CDw75 antigen is a sialylated carbohydrate epitope generated by the enzyme beta-galactosyl alpha-2,6-sialyltransferase. Although CDw75 antigen expression was found to be correlated with aggressive behaviour of tumour cells in gastric adenocarcinomas, its prognostic role still remains unknown. The objective of this study was to determine the value of CDw75 antigen expression as a marker of the metastatic potential and prognosis of gastric adenocarcinomas. CDw75 antigen expression was evaluated immunohistochemically in 64 tumours and their nodal metastases. The correlation was analysed between CDw75 antigen expression and selected clinicopathological variables, including survival. Positive staining was detected in 31 cases. Non-neoplastic gastric mucosa was consistently negative. CDw75 expression was correlated with larger tumour size (p<0.006), infiltrative growth pattern (p<0.044), advanced stage (p<0.0006), and positive lymph nodes (p<0.0003).The overall survival rate of patients with CDw75 expression was 28%, which was significantly worse than that of patients without CDw75 expression (53%) (p<0.0005). Multivariate analysis showed that CDw75 expression was an independent prognostic indicator, together with the growth pattern of the tumour. These results indicate that immunohistochemical detection of CDw75 antigen expression may be a good indicator of metastatic potential and of prognosis in patients with gastric carcinomas.  相似文献   
58.
Recently described distinct associations of HLA class II genes with ulcerative colitis (UC) suggest a genetic heterogeneity for disease susceptibility. In this study, HLA-DRB alleles of UC patients (n = 59) from Turkey were investigated and compared with healthy controls (n = 244). Using molecular genotyping by polymerase chain reaction (PCR) and sequence-specific oligonucleotide hybridization, we have shown a positive association of UC patients with the HLA-DRB1*1502 allele (10/59 vs. 16/244; P = 0.02; OR: 2.9) and a negative association with the DRB1*13 allele (7/59 vs. 64/244; P = 0.03; OR: 0.38) compared to controls. HLA-DRB1*0701 was significantly increased in perinuclear antineutrophil cytoplasmic antibody (pANCA)-positive UC patients compared to pANCA-negative patients (8/32 vs. 0/27; P = 0.005), whereas DRB1*1502 was observed more frequently in pANCA-negative patients (8/27 vs. 2/32; P = 0.03). These results extended the reported positive association of DRB1*1502 with UC to another population and supported the genetic susceptibility associated with HLA genes for disease development.  相似文献   
59.
60.
A case of ossifying fasciitis occurring in the left femoral region of a 57-year-old male is reported. The patient complained of pain in his left lower extremity which was the site of previous catheterization. During a left femoropopliteal by-pass, a firm and cylindric mass measuring 5 x 3 x 2.5 cm in size was found and extracted from the left groin. Histologically, a reactional lymph node and an irregularly shaped lesion extended into the perinodal fat tissue which is composed of proliferating fibroblasts with occasional mitotic activity. Within this fibroblastic proliferation, immature woven bone composed of osteoid with calcification and chondroid differentiation were seen. Metaplastic bone is an uncommon finding in cases of nodular fasciitis, parosteal fasciitis, cranial fasciitis and florid reactive periostitis. Ossifying fasciitis is known as an uncommon variant of nodular fasciitis. It is an uncommon post-traumatic benign lesion of subcutaneous tissue with an unclear etiology of ossification which is neither related with a bony structure nor contains any muscle tissue. This lesion has been reported only once previously, in the femoral region after a trauma history of catheterization.  相似文献   
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