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21.
1. It has been suggested that oestrogen-produced vasodilatation is due to induction of endothelial nitric oxide synthase (NOS), but there are many reports of direct effects on vascular smooth muscle. In the present study, these processes were investigated in rat aorta isolated from ovariectomized rats. 2. Short-term treatment (10min) with 17β-oestradiol (10 μmol/L) produced a small attenuation of the phenylephrine (PE)-induced constriction, which was unaffected by the nitric oxide synthase inhibitor l-N 5(-1-iminoethyl)ornithine (NIO; 100μmol/L). Long-term treatment (6h) with 17β-oestradiol (10 μmol/L) did not affect acetylcholine-mediated vasorelaxation in endothelium-intact aortic rings, but did attenuate PE-induced constriction. This attenuation was also observed in endotheliumdenuded preparations after 17β-oestradiol (10 μmol/L for 6h) and was far greater than the acute effect of 17β-oestradiol (10 μmol/L). 3. The attenuation produced by 17β-oestradiol (10 μmol/L for 6 h) was significantly inhibited by concomitant treatment with cycloheximide (1 μmol/L), suggesting that protein synthesis was involved. NIO (100 μmol/L) also attenuated the effect, which suggests that the anti-constrictor effect of 17β-oestradiol occurs through the increased production of nitric oxide (NO). 17β-Oestradiol increased NO production, as assessed by the conversion of [3H]-arginine to [3H]-citrulline in rat aorta. These effects were prevented by cycloheximide and NIO. The anti-constrictor effect of oestrogen was blocked by the oestrogen receptor antagonist ICI 182780 (100nmol/L). 4. Western blotting using an antibody specific for inducible nitric oxide synthase (NOS) revealed that 17β-oestradiol (10 μmol/L for 24 h) treatment induced the formation of inducible NOS protein in the aorta, an effect blocked by cycloheximide. The results indicate that 17β-oestradiol can attenuate the vasoconstrictor effect of PE by a specific receptor-mediated process that involves induction of inducible NOS.  相似文献   
22.
Open-label, phase II clinical trial was conducted in 40 HIV/TB dually infected patients to evaluate the effect of oral immunomodulator Dzherelo on immune and viral parameters. The anti-retroviral therapy naïve patients were randomized into two equal groups to be given anti-tuberculosis therapy (ATT) under DOTS. The arm A, which served as a control, received Isoniazid (H); Rimfapicin (R); Pyrazinamide (Z); Streptomycin (S); and Ethambutol (E), and arm B received 50 drops of Dzherelo twice per day in addition to the daily dose of HRZSE. After 2months the total CD3+ lymphocytes increased from 728 to 921cells/μl (P = 0.025) in Dzherelo recipients, whereas in the control group they decreased from 651 to 585 cells (P = 0.25). The population of CD4 T-cells expanded in Dzherelo arm (174 to 283; P = 0.00003) but declined in ATT group (182 to 174; P = 0.34). The CD8 cells fluctuated slightly upward in both groups: 159 > 180 (P = 0.17) and 159 > 183 (P = 0.13). The ratio between CD4/CD8 cells deteriorated in arm A (1.213 > 0.943; P = 0.002) but improved in arm B (1.244 > 1.536; P = 0.007). The percent of CD3+HLA-DR+ activated lymphocytes had fallen in ATT group (22.6 > 20.5; P = 0.004), but rose in Dzherelo recipients (21.5 > 30.5; P = 0.0001). The changes in CD20+ B lymphocytes were insignificant in both arms (28.4% > 28.6%; P = 0.4) and (27.2% > 26.7%; P = 0.38). No difference was seen in the amount of CD3-CD16+CD56+ natural killer (NK) cells in arm A (21.3% > 22.6%; P = 0.1), while in Dzherelo recipients they declined significantly (19.9% > 14.5%; P = 0.0026). The viral load, measured by plasma RNA-PCR, decreased in Dzherelo group (2174 > 1558; P = 0.002), but increased in ATT group (1907 > 2076 copies/ml; P = 0.03). Dzherelo has a favorable effect on the immune status and viral burden in HIV/TB patients when given as the immunomodulating adjunct to ATT.  相似文献   
23.
The objectives of this study were to assess changes in the self-reported use of health care services after gatekeeping by general practitioners and a global budget were introduced in the health insurance plan for students at the University of Geneva, Switzerland, in October 1992. A random sample of 336 members of the University plan answered questions about their use of health care services during the year before (1992) and the year after (1993) the introduction of managed care. Similar data were collected among a random sample of 300 members of a comparison plan. All participants were 18–44 y old in 1992, spoke French and lived in Geneva. The proportion of insurees who visited specialists decreased by 10% in the University plan between 1992 and 1993 and remained unchanged in the comparison group. The proportion of insurees who visited general practitioners increased by 12% in the University plan and remained unchanged in the comparison group. No effects on the total number of health care visits, on hospitalisations or on use of medications were detected. The introduction of gatekeeping and of a global budget managed by physicians was associated with a transfer of patient visits from specialists to general practitioners.  相似文献   
24.
Telerehabilitation is a viable option to provide continuum of rehabilitation intervention in situations like the ongoing pandemic. Presently, there is no policy guidelines to the minimum standard of telerehabilitation. This paper describes procedures for telerehabilitation for people with blindness and low vision from the evidence-based practices from a premier eye institute in South India. The suggested guidelines can help develop and replicate similar models of telerehabilitation to reach people in need in difficult situations like COVID 19 pandemic.  相似文献   
25.
The treatment of malignant histiocytosis   总被引:1,自引:0,他引:1  
Twenty-four consecutive cases of malignant histiocytosis (MH) treated at Stanford Medical Center between 1973 and 1983 have been reviewed. Most patients presented with systemic symptoms (91%) and advanced disease (stage IV, 80%). Multiple organ involvement was common. In six cases, pathologic tissue was further characterized by frozen section immune histochemistry, using a panel of monoclonal antibodies known to react with monocytes and macrophages, as well as a variety of hematopoietic cells. One case expressed a mature monocyte/macrophage phenotype; three cases were considered null cell or primitive lesions; and two cases were identified as probable T cell lymphomas. Seven patients underwent splenectomy. Two patients died prior to any treatment. Twenty-two patients were treated with CHOP (cyclophosphamide, Adriamycin, vincristine, prednisone) +/- bleomycin (B), +/- midcycle high-dose methotrexate (HD-MTX) with leucovorin rescue. Seven patients received prophylactic intrathecal MTX. Of 22 evaluable patients, there was a 68% complete response rate (CR), a 23% partial response rate (PR), and a 9% no response rate (NR). Median duration of CR was 30+ months; median duration of PR was 2.4 months. Median survival for patients attaining a CR has not been reached v 3 months for the PR and NR groups. For all 24 patients, median survival was 2 years, with a 5-year actuarial survival of 40%. Multivariate analysis revealed that a platelet count less than 150,000 (P Cox = .005) and the dose of drug delivered (P Cox = .057) were the most important prognostic factors. Prophylactic intrathecal MTX therapy and splenectomy did not influence survival. Although MH is an aggressive disease with a poor prognosis, it is potentially curable. Systematic and aggressive treatment should further improve the outcome.  相似文献   
26.
Orbital involvement at diagnosis in multiple myeloma is rare. Only a few a cases are reported with computed tomographic features. We report a case of orbital myeloma, and relevant medical reviews on computed tomography features are discussed.  相似文献   
27.
Rodent cholangiocytes express 6 of the 11 known channel proteins called aquaporins (AQPs) that are involved in transcellular water transport in mammals. However, clarifying the role of AQPs in mediating water transport in biliary epithelia has been limited in part because of the absence of physiologically relevant experimental models. In this study, we established a novel AQP4-transfected polarized mouse cholangiocyte cell line suitable for functional studies of transepithelial water transport, and, using this model, we define the importance of this AQP in water transport across biliary epithelia. Polarized normal mouse cholangiocytes (NMCs) lacking endogenous AQP4 were transfected stably with functional AQP4 or cotransfected with functional AQP4 and a transport-deficient AQP4 dominant negative mutant using a retroviral delivery system. In transfected NMCs, AQP4 is expressed on both the mRNA and protein levels and is localized at both the apical and basolateral membranes. In nontransfected NMCs, the transcellular water flow, P(f), value was relatively high (i.e., 16.4 +/- 3.2 microm/sec) and likely was a reflection of endogenous expression of AQP1 and AQP8. In NMCs transfected with AQP4, P(f) increased to 75.7 +/- 1.4 microm/sec, that is, by 4.6-fold, indicating the contribution of AQP4 in channel-mediated water transport across MNCs monolayer. In cotransfected NMCs, AQP4 dominant negative reduced P(f) twofold; no changes in P(f) were observed in NMCs transfected with the empty vector. In conclusion, we developed a novel polarized mouse cholangiocyte monolayer model, allowing direct study of AQP4-mediated water transport by biliary epithelia and generated data providing additional support for the importance of AQP4 in cholangiocyte water transport.  相似文献   
28.

Introduction  

Previous meta-analyses of magnesium sulphate infusion in the treatment of aneurysmal subarachnoid hemorrhage (SAH) have become outdated due to recently published clinical trials. Our aim was thus to perform an up-to-date systemic review and meta-analysis of published data on the use of magnesium sulphate infusion in aneurysmal SAH patients.  相似文献   
29.
人胰腺α-淀粉酶的cDNA克隆和原核表达的初步研究   总被引:4,自引:0,他引:4  
目的 获得人胰腺α-淀粉酶(AMY2A)基因并进行原核表达。方法 采用基因工程技术,根据人AMY2A基因序列设计并合成特异性引物;从人胰腺组织中提取总RNA,反转录成CDNA第一链;逆转录-聚合酶链反应(RT-PCR)扩增人胰腺AMY2A基因,经BamH Ⅰ和Kpn Ⅰ双酶切、连接并插入原核表达载体pGEX-5T,构建pGEX-5T-AMY2A重组表达载体,在大肠杆菌BL21中异丙基硫代半乳糖苷酶(IPTG)诱导表达AMY2A蛋白。包涵体经尿素变性、复性及谷胱苷肽琼脂糖柱亲和层析纯化、AMY2A酶活性测定和免疫印迹分析。结果 重组质粒测序和酶切结果显示AMY2A基因已正确插入pGEX-5T,重组蛋白、复性及纯化产物SDS聚丙烯酰胺凝胶电泳(SDS-PAGE)在84 000处有一条明显的蛋白表达条带,AMY2A检测具有酶活性,免疫印迹分析表明重组蛋白具有人胰腺淀粉酶抗原性。结论 作者已克隆并在大肠杆菌中初步表达并获得纯化的谷胱苷肽转移酶(GST)-AMY2A融合蛋白。  相似文献   
30.
介绍了吉安电视台全硬盘自动播出网络系统设计指导思想及系统构成,该系统采用网络技术实现资源共享,采用多级安全措施确保安全播出.  相似文献   
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