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991.
992.
雌二醇调节树突状细胞功能参与狼疮鼠的发病机制   总被引:1,自引:0,他引:1  
目的 比较雌二醇(E2)对SLE模型鼠-(NZB×NZW)F1(NZB/w F1)雌鼠发病前后脾脏树突状细胞(DC)的影响,探索雌激素对DC的调节是否和系统性红斑狼疮(SLE)的进展相关.方法 抗CD11c单抗标记的免疫磁珠纯化DC,流式细胞仪检测DC表面分子和细胞因子,混合淋巴细胞反应检测DC对脾脏T细胞的刺激功能,半定量反转录一聚合酶链反应(RT-PCR)法检测DC内雌激素受体(ER)的表达.结果 E2影响狼疮鼠脾脏DC的CD40、白细胞介素(IL)-6、IL-10、IL-12、肿瘤坏死因子(TNF)-α和ERα的表达及刺激活性;枸橼酸他莫西芬(TAM)拈抗E2的作用;E2对不同周龄鼠DC的作用不同.结论 E2通过与DC的ERα结合而调控DC来参与SLE的病理机制,E2对DC的作用和病程进展有关.  相似文献   
993.
We present 2 cases of hepatocyte nuclear factor 1α (HNF1α)-mutated adenomatosis, discovered for reasons unrelated to this disease, and identified using immunohistochemical methods. These new tools may further our understanding of the link between adenomas/adenomatosis subtypes and their complications, and their association with other abnormalities.  相似文献   
994.
Overall, 133 patients underwent 170 procedures for the treatment of persistent ATa following an index cryoballoon pulmonary vein isolation (n = 715). After all the procedures, > 90% of the patients had a roof line, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. Ninety-two patients (69.2%) were in sinus rhythm after a median of 36 months since the index cryoballoon PVI. ATa: atrial tachyarrhythmia; cryo: cryoballoon; CTI: cavotricuspid isthmus; LSPV: left superior pulmonary vein; LIPV: left inferior pulmonary vein; PVI: pulmonary vein isolation; RF: radiofrequency; RSPV: right superior pulmonary vein; RIPV: right inferior pulmonary vein.
  相似文献   
995.
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996.
Mellander A  Järbur K  Sjövall H 《Gut》2000,46(3):376-384
BACKGROUND: Motor disturbances are sometimes associated with diarrhoea by unknown mechanisms. AIM: To determine if there is a quantitative link between intestinal motility and epithelial secretion. SUBJECTS: Experiments were performed in 21 healthy volunteers and three patients with villus atrophy. METHODS: Duodenal and jejunal motor activities were registered in the fasted state by open tip manometry. Secretion was measured directly by marker perfusion and indirectly by recording transmural potential difference (PD). RESULTS: A significant correlation was found between "low pass filtered" pressure and PD, but no correlation was found between amplitudes of isolated contractions and PD changes. During repeated phasic contractions (phase III of migrating motor complex), PD increased at a rate that was higher in the duodenum than in the jejunum, and higher in patients with villus atrophy than in healthy controls. After reaching a peak, PD decreased despite continuing phasic motor activity, provided that there was no concomitant increase in mean pressure. Fluid secretion increased roughly in parallel with PD, except at the very end of the cycle. CONCLUSIONS: To explain these findings, one has to postulate participation of at least two types of receptor: a slowly adapting pressure sensitive receptor and another mechanoreceptor, possibly a mucosal touch receptor, to account for the run down phenomenon. This model predicts that short lasting trains of contractions, so called discrete clusters, will be a particularly potent stimulus for activation of mucosal secretion.  相似文献   
997.
本文对脑型和混合型猪囊尾蚴病患者脑脊液(CSF)中特异循环免疫复合物(CIC)进行了检测,其结果与患者CT表现及吡喹酮治疗第一个疗程过程中患者出现的高颅压情况存在一定联系。人工免疫复合物(IC)对BALB/c鼠作用后进行病理检查,发现脑实质和肾脏小血管均出现充血现象.部分小血管内皮细胞遭到破坏。因此认为特异循环免疫复合物可能是脑型、混合型猪囊尾蚴病患者在第一疗程中出现高颅压反应的主要因素之一。  相似文献   
998.
Cardiac microsomes prepared by two different methods were compared in terms of Ca-binding and Ca-uptake, believed to represent markers for fragmented sarcoplasmic reticulum, and the (Na+ + K+)-activated ATPase activity considered to be a marker for the plasma membrane. Microsomes prepared in dilute buffer (H2O-microsomes) contain two to four times the activity of sarcoplasmic reticulum markers when compared to microsomes prepared in 10% sucrose (suc-microsomes). Conversely, the plasma membrane marker was present in greater amounts in the suc-microsomes. Basal, epinephrine-stimulated and NaF-stimulated adenylate cyclase activities were slightly higher in H2O-microsomes, as was the degree of stimulation by the β-adrenergic agonist. These findings provide evidence that both β-receptor and adenylate cyclase activities may be present in the heart's sarcoplasmic reticulum, as well as in the sarcolemma.  相似文献   
999.
1000.
BACKGROUND: Lymphangioleiomyomatosis (LAM), a multisystem disease occurring primarily in women, is characterized by cystic lung destruction, and kidney and lymphatic tumors, caused by the proliferation of abnormal-appearing cells (ie, LAM cells) with a smooth muscle cell phenotype that express melanoma antigens and are capable of metastasizing. Estrogen receptors are present in LAM cells, and this finding, along with reports of disease progression during pregnancy or following exogenous estrogen administration, suggest the involvement of estrogens in the pathogenesis of LAM. Consequently, antiestrogen therapies have been employed in treatment. The goal of this prospective study was to evaluate the efficacy of triptorelin, a gonadotrophin-releasing hormone analogue, in 11 premenopausal women with LAM. METHODS: Patients were evaluated at baseline and every 3 to 6 months thereafter, for a total of 36 months. Hormonal assays, pulmonary function tests, 6-min walk tests, high-resolution CT scans of the chest, and bone mineral density studies were performed. RESULTS: Gonadal suppression was achieved in all patients. Overall, a significant decline in lung function was observed; two patients underwent lung transplantation 1 year after study enrollment, and another patient was lost to follow-up. Treatment with triptorelin was associated with a decline in bone mineral density. CONCLUSIONS: Triptorelin appears not to prevent a decline in lung function in patients with LAM. Its use, however, may be associated with the loss of bone mineral density.  相似文献   
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