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101.
A 41‐year‐old man presented with a 4‐year history of progressive right‐sided diplopia on lateral gaze and right nasolabial paraesthesia. A CT revealed minor bone erosion of Meckel’s cave and of the right petrous apex by a uniformly enhancing lesion at the base of the skull. Magnetic resonance imaging on three occasions over 2 years showed tumour, measuring 4 cm in diameter, with features suggestive of a trigeminal neuroma. At surgery the lesion had the macroscopic appearance of a giant schwannoma. Histopathological findings were that of a meningeal haemangiopericytoma (HPC) of the trigeminal nerve. Intracranial HPC are rare and aggressive tumours of the central nervous system. They usually arise from the falx, tentorium and dural sinuses. The present case is unique as it originates from a cranial nerve.  相似文献   
102.
Thrombus formation and hemolysis have been linked to the dynamic flow characteristics of heart valve prostheses. To enhance our understanding of the flow characteristics past the aortic position of a Jellyfish (JF) valve in the left ventricle, in vitro laser Doppler anemometry (LDA) measurements were carried out under physiological pulsatile flow conditions. The hemodynamic performance of the JF valve was then compared with that of the St. Vincent (SV) valve. The comparison was given in terms of mean systolic pressure drop, back flow energy losses, flow velocity, and shear stresses at various locations downstream of both valves and at cardiac outputs of 3.5 L/min, 4.5 L/min, and 6.5 L/min respectively. The results indicated that both valves created disturbed flow fields with elevated levels of turbulent shear stress as well as higher levels of turbulence in the immediate vicinity of the valve and up to 1 diameter of the pipe (D) downstream of the valve. At a location further downstream, the JF valve showed better flow characteristics than the SV in terms of velocity profiles and turbulent shear stresses. The closure volume of the SV valve was found to be 2.5 times higher than that of the JF valve. Moreover, the total back flow losses and mean systolic pressure drop also were found to be higher in the SV than the JF valve.  相似文献   
103.
Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder, occurring predominantly in women. We studied by flow cytofluorimetry the T cell subsets in men and women with ITP and compared them with healthy sex-matched volunteers. In healthy controls, women were found to have higher proportions of T helper/inducer (Th/i) and lower T suppressor/cytotoxic (Ts/c) lymphocytes and consequently higher Th/i:Ts/c ratios than men. Accordingly, in clinical surveys, patients and controls should be matched for sex for proper comparisons. In patients with ITP in its active phase, an imbalance in T cell subsets was found in both sexes. The perturbation was more severe in women who had a marked decrease in number and proportion of Th/i lymphocytes and an increase in the proportion of Ts/c lymphocytes, whereas in men only, the proportion of Th/i lymphocytes was decreased. When patients with active disease were compared to those with ITP in remission, the decrease in Th/i subsets still persisted in both sexes but the Ts/c subset in women had returned to normal proportions. Therefore, the immune imbalance in ITP is more marked in women than men; imbalances in both Th/i and Ts/c are present in women while Ts/c appears not to be involved in men.  相似文献   
104.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation.  相似文献   
105.
过敏性休克死亡豚鼠脏器中IgE蛋白表达   总被引:2,自引:0,他引:2  
肖凤  温永顺  王伴青 《医学争鸣》2005,26(18):1719-1720
目的:检测过敏性休克死亡豚鼠脏器中IgE的蛋白表达情况,探讨法医学鉴定过敏性休克的病理形态学诊断标准. 方法:建立豚鼠异种血清过敏性休克模型,利用组织芯片技术、采用免疫组化方法SP法检测25例过敏性休克死亡鼠脏器中IgE蛋白的表达情况,并与常规切片比较. 结果:过敏性休克死亡豚鼠在肺小血管壁及其血管周围 ,气管黏膜上皮内、小血管壁及结缔组织和脾髓质中IgE蛋白呈阳性表达,而肝、肾、心等脏器中IgE蛋白表达呈阴性. 结论:过敏性休克时,肺、气管和脾组织中可检见IgE.  相似文献   
106.
107.
The ideal standard of treatment of the infected sternotomy wound is early recognition, adequate debridement and repair with well vascularised tissue. We describe a new technique The Waist Coat Flap, which adheres to these principles, but does not require muscle or omentum and does not compromise their future use, if required.  相似文献   
108.
The cycloaddition of the newely synthesized 5-(2-thienyl)methylene derivatives of thiazolidinone-4-thiones,2a?c to acrylonitrile (3a), ethyl acrylate (3b), N-phenylmaleimide (6) and dimethyl fumarate (8) has been evaluated. Under thermal reaction conditions [4+2] cycloaddition proceeds with complete site and regioselectivity to yield the cycloadduct,4, 5, 7 and9, respectively. The antimicrobial activities of some of the new products were tested.  相似文献   
109.
110.
This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.   相似文献   
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