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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Jennes W Sawadogo S Koblavi-Dème S Vuylsteke B Maurice C Roels TH Chorba T Nkengasong JN Kestens L 《The Journal of infectious diseases》2003,187(2):206-214
Cellular factors that may protect against human immunodeficiency virus (HIV) infection were investigated in 27 HIV-exposed seronegative (ESN) female sex workers (FSWs) and 27 HIV-seronegative female blood donors. Compared with blood donors, ESN FSWs had significantly decreased expression levels of C-X-C chemokine receptor 4 (CXCR4), but not of C-C chemokine receptor 5, on both memory (P<.001) and naive (P=.041) CD4(+) T cells. CXCR4 down-regulation was associated with prolonged duration of commercial sex work by ESN FSWs. CD38 expression on CD8(+) T cells was significantly increased among ESN FSWs, compared with that among blood donors (P=.017). There were no differences in HLA-DR and CD62L expression between blood donors and ESN FSWs. Proportions of T cells producing the beta-chemokines RANTES (regulated on activation, normally T cell-expressed and -secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta or the cytokines interleukin (IL)-2, IL-4, interferon-gamma, and tumor necrosis factor-alpha, were similar in the 2 groups. These data indicate that ESN FSWs differ from HIV-seronegative female blood donors with respect to immunological factors that have no clear protective potential against HIV transmission. 相似文献
972.
973.
Y Juillière J Anconina P Buffet S Everaere O Perrin V Berder C Kettani F Schrijen N Danchin F Cherrier 《Archives des maladies du coeur et des vaisseaux》1992,85(9):1305-1310
This clinical study analysed the changes in right ventricular ejection fraction induced by changes in right ventricular afterload using a new thermodilution catheter linked to a rapid response computer which allowed instantaneous measurements of the right ventricular ejection fraction. The first group comprised 16 patients referred for coronary angioplasty with single vessel disease (isolated proximal stenosis of one of the two main branches of the left coronary artery) and a normal left ventricular ejection fraction (> or = 55%) and mean pulmonary artery pressure of < 25 mmHg: right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after 60 seconds' coronary occlusion with the balloon catheter in order to assess the effects of the reactional increase in afterload on the right ventricular ejection fraction. The second group comprised 11 patients with dilated primary cardiomyopathy with decreased left ventricular ejection fraction (< 50%) and mean pulmonary artery pressure > or = 25 mmHg: the right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after intravenous trinitrin (performed to evaluate the pulmonary reaction to vasodilators) in order to analyse the effects of the reduction of afterload on right ventricular ejection fraction. Negative linear correlations were observed between the right ventricular ejection fraction and mean pulmonary artery pressure under basal conditions (r = -0.72; p < 0.005) and between the right ventricular ejection fraction and mean pulmonary artery pressure after changing the conditions of afterload (r = -0.82; p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
974.
Dr. Michèle Gue BS Jean Fioramonti DS Jacques Frexinos MD M. Alvinerie BS Lionel Bueno DS 《Digestive diseases and sciences》1987,32(12):1411-1417
The effects of acoustic stress (AS) on gastrointestinal motility and their prevention by previous treatment with naloxone, phentolamine, propranolol, muscimol, and diazepam were investigated in intact and vagotomized fasted dogs fitted with chronically implanted strain gauges on the antrum at 10 cm from pylorus and on the jejunum at 70 and 140 cm from the pylorus. These effects were compared to those produced by intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Beginning 40–50 min after the occurrence of a gastric migrating motor complex (MMC), a 1-hr hearing of prerecorded intense music through earpieces (<100 dB) delayed the occurrence of the next gastric MMC observed after 2.8±1.2 hr, while jejunal MMC were still present at a normal frequency. During AS, heart rate and plasma cortisol were significantly increased by 32.7 and 215%, respectively, 10–15 min after the beginning of hearing. The AS-induced lengthening of the gastric MMC cycle as well as cortisol increase were abolished after previous administration of diazepam (0.5 mg/kg intramuscular) or muscimol (10 g/kg intravenous), while they were still present after naloxone (0.1 mg/kg intravenous), phentolamine (0.2 mg/kg intravenous), or propranolol (0.1 mg/kg intravenous). CRF administered intracerebroventricularly (100 ng/kg) also delayed the occurrence of gastric MMC without affecting jejunal motility, and this effect was not antagonized by previous treatment with diazepam or muscimol. Both the effects of AS and CRF were abolished after bilateral thoracic vagotomy. These results suggest that the selective inhibition of gastric motility induced by noise in dog is due to the CNS release of CRF which affects, in turn, the vagal output to the stomach. The suppressive action of diazepam or GABA agonist on noise-induced gastric hypomotility may be related to blockade of the AS-induced CRF release. 相似文献
975.
大剂量脑脊液等量置换及椎管内尿激酶注射救治蛛网膜下腔出血的临床研究 总被引:10,自引:0,他引:10
目的 探索救治蛛网膜下腔出血 (SAH)患者的有效方法。方法 对经头颅螺旋CT或磁共振成像及腰穿确定 ,有剧烈头痛、恶心、呕吐 ,应用常规降颅压及止痛无效的 2 8例SAH患者 ,用大剂量生理盐水置换脑脊液和椎管内尿激酶注射治疗 ,并与对照 1组单纯大剂量脑脊液置换 10例和对照 2组单纯小剂量生理盐水置换脑脊液 12例进行比较。结果 治疗组 18例即刻 (1h)、2 4h、72h、5d症状明显减轻至消失 ,72h缓解 2 7例 (96 .4 %) ,所有患者均未出现速发或迟发性脑血管痉挛 (CVS)现象。对照 1组 10例 72h缓解 6例 (6 0 %) ,1例发生迟发性CVS征象 ,与治疗组比较差异有显著性意义 (P <0 .0 5 )。对照 2组 2例 2 4h内症状明显减轻 ,72h基本缓解 ,其他患者症状持续时间均在 72h以上 ,最长持续达 1周 ,4例 (33%)发生迟发性CVS ,死亡 2例。结论 应用大剂量生理盐水置换脑脊液可快速消除SAH患者之急性症状 ,对CVS也有较好治疗和预防作用 ,而早期加用小剂量尿激酶椎管内注射 ,可以明显提高以上疗效 ,同时又不会增加再出血的危险 相似文献
976.
977.
978.
Contribution of Toll-like receptors to the innate immune response to Gram-negative and Gram-positive bacteria. 总被引:1,自引:0,他引:1
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Innate recognition of bacteria is a key step in the activation of inflammation and coagulation, and it is dependent on pathogen-associated molecular pattern (PAMP) ligation to Toll-like receptors (TLRs) and CD14. The dominant receptors activated when cells encounter a whole bacterium, which express several PAMPs, are poorly defined. Herein, we have stimulated various human cells with prototypic Gram-negative and Gram-positive bacteria. Receptor-dependent responses to whole bacteria were assessed using both TLR-transfected cells and specific monoclonal antibodies against TLRs, MD-2, and CD14. Enterobacteria-activated leukocytes and endothelial cells in a TLR4/MD-2-dependent manner, most likely via lipopolysaccharide (LPS). TLR2 activation was observed with a high bacterial inoculum, and in epithelial cells expressing TLR2 but not TLR4. Pseudomonas aeruginosa stimulated cells by both TLR2 and TLR4/MD-2. Gram-positive bacteria activated cells only at high concentrations, in a partially TLR2-dependent but TLR4/MD-2-independent manner. Either TLR or CD14 neutralization blocked activation to all bacterial strains tested with the exception of some Gram-positive strains in whole blood in which partial inhibition was noted. This study identifies dominant TLRs involved in responses to whole bacteria. It also validates the concept that host cell activation by bacterial pathogens can be therapeutically reduced by anti-TLR4, -TLR2, and -CD14 mAbs. 相似文献
979.
Baysse L Boralevi F Lepreux S Boyer A Morel C Léauté-Labrèze C Taïeb A 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》2003,24(6):394-398
BACKGROUND: Eccrine squamous syringometaplasia has been reported in some cases as an Herpeviridae complication. We report a case of eccrine squamous syringometaplasia associated with a severe cytomegalovirus infection in an immunocompromised patient, and we discuss about potential viral or drug triggering factors. METHODS: A 22 years-old man was hospitalized in an intensive care unit for rejection of a renal graft associated with a disseminated cytomegalovirus infection. A papular and papulopustular eruption appeared on the trunk and the limbs. RESULTS: Histological examination of a skin sample showed eccrine squamous syringometaplasia, with evidence of cytomegalovirus genomic sequences using PCR. Two weeks later, the patient developed toxic epidermal necrolysis, with fatal issue. CONCLUSIONS: Eccrine squamous syringometaplasia is a rare condition, without specific clinical features. Numerous local affections have been reported to induce eccrine syringometaplasia (ulcer, scar, pyoderma gangrenosum, drug injection.), drugs (cytotoxic agents, non steroidal anti inflammatory therapies) and in cases of infection due to cytomegalovirus or herpes simplex virus. The potential implication of cytomegalovirus or foscarnet as triggering factors in our case is discussed. This observation and other similar reported cases lead to the conclusion that eccrine squamous syringometaplasia may be an underestimated complication of cytomegalovirus infections in immunocompromised patients. 相似文献
980.
Retornaz F Durand JM Poullin P Lefèvre P Soubeyrand J 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》2000,21(9):777-784
INTRODUCTION: The objective of this work was to review current data about the physiopathology, clinical features, and treatment of thrombotic thrombocytopenic purpura (Moschowitz's syndrome). CURRENT KNOWLEDGE AND KEY POINTS: Thrombotic thrombocytopenic purpura is a rare disorder characterized by widespread thrombotic injuries of platelets in the microcirculation. Its physiopathology has been elucidated recently. Evidence of a deficiency of Von Willebrand's factor-cleaving protease would be due to either IgG antibodies in the acute form of the disease or constitutional deficiency in the chronic form of the disease. FUTURE PROSPECTS AND PROJECTS: Plasma exchange is the current reference treatment. However, in the light of recent publications, either infusions of concentrates of purified enzyme or more intensive immunosuppressive therapy would be more specific. 相似文献