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141.
Migration and proliferation of vascular smooth muscle cells are early and major events in the formation of atherosclerotic lesions. We report on an aorta transplant model in rabbits wherein myointimal proliferation is inhibited by 17-beta-estradiol. The abdominal aortas of outbred white New Zealand rabbits were harvested and allografted to the carotid artery of the recipient. The animals, which were fed either a normal or a high-cholesterol (0.5%) diet, were killed 3 weeks later. The degree of myointimal proliferation was measured with a digitized system attached to a light microscope. The myointimal hyperplasia was expressed as the cross section area of the intima/the area of the intima + the area of the media x 100. Transmission electron micrographs were obtained for all vessels. Intimal thickening was shown mainly to consist of proliferating smooth muscle cells. The cholesterol diet resulted in significantly higher serum total cholesterol levels compared to animals on a normal diet (p < 0.0001) but did not affect serum high-density lipoprotein-cholesterol or serum triglyceride levels. The cholesterol diet was also associated with a greater but not significant amount of intimal thickening. Treatment with 17-beta-estradiol significantly decreased both serum triglyceride concentration (p < 0.05) and myointimal thickening (p < 0.01) in cholesterol-fed animals. Transmission electron microscopy showed that the endothelial cells appeared structurally normal in the estradiol-treated animals. Further, estradiol prevented the appearance of vacuolized macrophages. Thus estradiol may decrease myointimal thickening by preserving the endothelium and preventing macrophage appearance in the intima.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
142.
凝血因子Ⅷ(FⅧ)由vWF和FⅧ:C组成。FⅧ:C的合成部位至今尚未确认。本文检测了16~22周胎龄胎儿肝、脾、肾及肾小球组织中Ⅷ:C活性及vWF:Ag含量后,发现肾中Ⅷ:C活性较高(1.679±1.588 U/ml),尤其是肾小球中高达46.313±40.651U/ml,脾中次之(0.372±0.462 U/ml),肝中最低(0.021±0.029U/ml)。将3种组织细胞培养后,发现仍以肾中Ⅷ:C活性最高。由此提示,肾可能是Ⅷ:C的合成部位。同时检测三器官中vWF:Ag,发现含量极微。这些组织中Ⅷ:C与vWF的关系有待研究。  相似文献   
143.
Surgical results of total anomalous pulmonary venous connection (TAPVC) has been improved in recent years, however, late development of pulmonary venous obstruction was our concern in its total correction in early infancy. In the cardiac type of TAPVC, in which the pulmonary veins were connected to the right lateral wall, prosthetic patch is conventionally used in diversion of pulmonary venous flow into left atrium. It seemed favorable to repair this subset without using prosthesis. A 3-month-old female with TAPVCIIb according to Darling's classification underwent total correction on September 22th, 1988. Two pedicled flaps were developed using the right atrial wall and the atrial septum to create a pulmonary venous channel to divert arterial blood into left atrium and absorbable sutures were used throughout. Right atrium was entered through a vertical incision in its body and all the pulmonary veins were found in a recess in the lateral wall of the right atrium. Atrial septal defect in the cranial aspect of the fossa ovalis was enlarged by cutting the primum tissue along the right limbus and its caudal margin so as to form a pedicled flap attached to the left limbic tissue. Then the flap was sutured along the limbus to create a roof of the fossa ovalis. The second flap was made in the middle of the lateral atrial wall and was used to create a tunnel from the recess to the atrial septal defect. The defect in the right atrial wall was closed directly and no prosthetic patch was used. Postoperative course was uneventful and echocardiogram showed wide pulmonary venous channel draining into the left atrium.  相似文献   
144.
M Xu  B Xiong  P Cheng  Y Guo 《中国中药杂志》1992,17(4):228-30, 256
Five compounds have been isolated from the stems and leaves of Isodon albopilosus. On the basis of spectroscopic and chemical data, they were identified as macrocalyxin C, stearic acid, beta-sitosterol, ursolic acid and beta-sitosterol-beta-D-glucoside, respectively.  相似文献   
145.
146.
运用扫描电镜和光镜观察了人脐带静脉的形态结构及其在0~8.0kPa 压力下的变化.脐静脉结构类似中等动脉.内皮细胞和内弹力膜的形态随实验压力增大而改变.6.7~7.3kPa是脐静脉内膜的临界破坏压,5.3~6.7kPa 是制备脐静脉作为管道移植材料的最佳压力.  相似文献   
147.
The over-representation of chromosome 12p sequences is crucial for the development of invasive testicular germ cell tumors. Testicular cancer patients may have metastatic tumors of diverse histologic types, including adenocarcinoma, undifferentiated carcinoma, sarcoma, or other malignancies that lack features of germ cell tumors. We sought to investigate the possible germ cell origin of such tumors using interphase fluorescence in situ hybridization. In all, 10 metastatic malignant somatic-type tumors from patients with histories of testicular cancer, as well as one malignant somatic-type tumor from a patient with primary mediastinal germ cell tumor were studied and included: adenocarcinoma (five cases), poorly differentiated carcinoma (one), sarcoma (four), and neuroendocrine carcinoma (one). The tumors were analyzed using fluorescence in situ hybridization using 12p spectrum green and 12 centromeric spectrum orange probes in paraffin sections. The patients ranged in age from 27 to 55 years (mean, 43). Colon and lung cancers from patients without germ cell tumors were used as controls. Adequate signals were observed in all tumors. Gain of chromosome 12p was seen in six tumors. None of the control tumors showed 12p amplification. Fluorescence in situ hybridization for 12p amplification in routinely processed surgical specimens is a useful adjuvant diagnostic tool in confirming the germ cell origin of metastatic tumors having the histologic appearance of somatic-type neoplasms.  相似文献   
148.
BACKGROUND: A recent report provided evidence that a disintegrin and metalloprotease domain 33 (ADAM33), a member of the ADAM family, is a novel susceptibility gene in asthma linked to bronchial hyper-responsiveness. However, there has been no investigation of the genetic role of ADAM33 variants in nasal allergy. OBJECTIVE: The purpose of this study was to test the association between ADAM33 polymorphisms and Japanese cedar pollinosis (JCPsis), a most common seasonal allergic rhinitis in Japan. METHODS: We conducted a case-control association study among a Japanese population, involving 95 adult individuals with JCPsis and 95 normal healthy controls. A total of 22 single-nucleotide polymorphisms (SNPs) in ADAM33 were genotyped using PCR-based molecular methods. RESULTS: Six SNPs of ADAM33 gene, three in introns (7575G/A, 9073G/A and 12540C/T) and three in the coding region (10918G/C, 12433T/C and 12462C/T), were strongly associated with JCPsis (P = 0.0002-0.022 for absolute allele frequencies) and most of the SNPs were in linkage disequilibrium with each other. A higher frequency of the common alleles of these SNPs was noted for the subjects with JCPsis in comparison with healthy controls. We also identified a haplotype associated with the disease susceptibility. In addition, associations were found between ADAM33 polymorphisms and various cedar pollinosis phenotypes including clinical severity, eosinophil counts in nasal secretion and allergen-specific IgE levels in sera, but not total serum IgE levels. CONCLUSION: These results indicate that polymorphisms in the ADAM33 gene are associated with susceptibility to allergic rhinitis due to Japanese cedar pollen, but the functional relationship still needs clarification.  相似文献   
149.
Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia.  相似文献   
150.
A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children.  相似文献   
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