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141.
142.
Plasma RNA viral load in human immunodeficiency virus type 2 subtype A and subtype B infections 总被引:4,自引:0,他引:4 下载免费PDF全文
Damond F Gueudin M Pueyo S Farfara I Robertson DL Descamps D Chène G Matheron S Campa P Brun-Vézinet F Simon F 《Journal of clinical microbiology》2002,40(10):3654-3659
Human immunodeficiency virus type 2 (HIV-2) is much less pathogenic than HIV-1, and HIV-2 infection is associated with plasma viral loads significantly lower than those found in HIV-1 infection. We have developed a real-time quantitative PCR method for measuring the HIV-2 RNA load that covers the range of genetic diversity of HIV-2 isolates and that detects extremely low viral loads. Samples from 49 patients were studied. Proviral DNA was first detected and quantified. The strains that were detected were then genotyped: 21 patients were infected with HIV-2 subtype A and 15 patients were infected with HIV-2 subtype B; 1 patient was infected with a highly divergent strain. Env PCR failed for the remaining 12 patients, so subtypes could not be determined. For viral RNA quantification, a stock of HIV-2 strain NIHZ, which was counted by electron microscopy, was used as the standard. Several primer sets targeting the highly conserved gag region were evaluated. Various primer combinations failed to amplify subtype B strains. With the final primer pair selected, which detected both subtype A and subtype B strains, the sensitivity of the assay was 100% at a viral load of 250 copies/ml and 66% at a viral load of 125 copies/ml. We found a correlation between the CD4(+)-cell count, the clinical stage, and the plasma HIV-2 RNA level. The median plasma HIV-2 RNA value for the 33 asymptomatic patients was 2.14 log(10), whereas it was 3.1 log(10) for the 16 patients with AIDS (P < 0.01). Proviral DNA was detectable in 18 symptom-free patients with high CD4(+)-cell counts, in whom viral RNA was undetectable. 相似文献
143.
Ph. Wind A. Alves J. M. Chevallier C. Gillot J. P. Sales A. Sauvanet Ch. A. Cuénod V. Vilgrain P. H. Cugnenc V. Delmas 《Surgical and radiologic anatomy : SRA》1998,20(2):129-134
Summary Portal hypertension is characterised by the development of a collateral portocaval circulation. Among these venous reroutings, some are situated posteriorly in the left subphrenic compartment. These are the spontaneous splenorenal and gastrorenal anastomoses. Their incidence is estimated at around 16%. On the one hand, there are the direct shunts, which anastomose the spelling v. to the left renal v., of an anecdotal nature, and on the other the spontaneous indirect splenorenal shunts, characterised by the presence of a complete neurovascular pedicle traversing the gastrophrenic ligament. This relates to the gastric collateral v., which is connected to the left renal v. via the inferior v. of the left crus of the diaphragm and the middle capsular v., hence the name gastro-phreno-capsulorenal shunt. At an advanced stage of portal hypertension these splenorenal shunts may acquire a major caliber and behave like actual surgical shunts.
Anatomie des anastomoses veineuses spléno-rénale et gastro-rénales spontanées: revue de la littérature
Résumé L'hypertension portale se caractérise par le développement d'une circulation collatérale porto-cave. Parmi ces dérivations veineuses, certaines ont une topographie postérieure, localisée dans la loge sous-phrénique gauche. Ce sont les anastomoses spontanées splénorénales et gastro-rénales. Leur prévalence est estimée aux alentours de 16%. On distingue, d'une part, les shunts directs, qui anastomosent la v. splénique à la v. rénale gauche, de constatation anecdotique, non systématisés sur le plan anatomique ; d'autre part, les shunts splénorénaux spontanés indirects caractérisés par l'existence d'un pédicule complet vasculo-nerveux, cheminant dans le ligament gastro-phrénique. Il s'agit de la v. collatérale gastrique qui est reliée à la v. rénale gauche par l'intermédiaire de la v. inférieure du pilier gauche du diaphragme et de la v. capsulaire moyenne, d'où le nom de shunt gastro-phrénocapsulo-rénal. A un stade avancé de l'hypertension portale, ces shunts splénorénaux peuvent acquérir un calibre important et se comporter alors comme de véritables shunts chirurgicaux.相似文献
144.
CD56 is immunohistochemically detectable in virtually all small cell carcinomas on frozen sections. The authors retrospectively tested the usefulness of the monoclonal antibody 123C3 against CD56 to differentiate pulmonary and extrapulmonary small cell carcinomas from nonneuroendocrine non—small cell carcinomas by paraffin-section immunohistochemistry after antigen retrieval. The study included 70 small cell carcinomas and 344 primary and metastatic nonneuroendocrine carcinomas of various primary sites. The staining results were compared with specific neuroendocrine markers (CD57, Chromogranin A, Synaptophysin). The monoclonal antibody 123C3 diffusely stained most small cell carcinomas with a strong membranous pattern (sensitivity: 0.99). The staining intensity was not diminished in areas with crush artifacts or after decalcification. The neuroendocrine markers had a combined sensitivity of only 0. 44 for small cell carcinomas. With regard to nonneuroendocrine carcinomas, the 123C3 antibody stained 7 of 28 ovarian carcinomas, 6 of 30 renal cell carcinomas, 2 of 10 endometrial carcinomas, two of three nonneuroendocrine large cell carcinomas of the lung, 1 of 38 adenocarcinomas, and 4 of 52 squamous cell carcinomas of the lung. Urothelial carcinomas, hepatocellular carcinomas, squamous carcinomas of the head/neck and cervix uteri, as well as adenocarcinomas of the breast, stomach, colon, pancreas, and prostate, showed no immunoreactivity for CD56. The specificities of 123C3 and the combined neuroendocrine markers for small cell carcinomas were 0. 94 and 0. 95, respectively. The authors conclude that monoclonal antibody 123C3 might be useful for the immunohistochemical differentiation of small cell carcinomas from nonneuroendocrine carcinomas on paraffin sections, especially in small and crushed biopsy specimens. 相似文献
145.
Fulminant hepatic failure induced oxidative stress in nonsynaptic mitochondria of cerebral cortex in rats 总被引:2,自引:0,他引:2
Fulminant hepatic failure (FHF) is a condition with sudden onset of necrosis of hepatocytes and degeneration of liver tissue without any established liver disease. FHF is associated with increased ammonia levels in blood and brain, which is supposed to be neurotoxic, ultimately leading to neuronal death. Evidences from previous studies suggest for mitochondrial dysfunctions under hyperammonemic conditions. In the present investigation, on thioacetamide-induced FHF rat models, studies were undertaken on cerebral nonsynaptic mitochondrial oxidative stress. The results of the present study reveal elevated lipid peroxidation along with reduced total thiol levels in the cerebral cortex mitochondria of experimental animals compared to saline treated control rats. In addition, the enzymatic activities of glutathione peroxidase and glutathione reductase were decreased, with an elevation in Mn-SOD activity. Overall, thioacetamide-induced FHF in rats enhanced the levels of lipid peroxidation coupled with impaired antioxidant defenses in the cerebral nonsynaptic mitochondria. 相似文献
146.
147.
F. Anselme K. Collomp B. Mercier S. Ahmaïdi Ch. Prefaut 《European journal of applied physiology》1992,65(2):188-191
Summary The aim of this study was to specify the effects of caffeine on maximal anaerobic power (W
max). A group of 14 subjects ingested caffeine (250 mg) or placebo in random double-blind order. TheW
max was determined using a force-velocity exercise test. In addition, we measured blood lactate concentration for each load at the end of pedalling and after 5 min of recovery. We observed that caffeine increasedW
max [964 (SEM 65.77) W with caffeine vs 903.7 (SEM 52.62) W with placebo;P<0.02] and blood lactate concentration both at the end of pedalling [8.36 (SEM 0.95) mmol · l–1 with caffeine vs 7.17 (SEM 0.53) mmol · l–1 with placebo;P<0.011 and after 5 min of recovery [10.23 (SEM 0.97) mmol · l–1 with caffeine vs 8.35 (SEM 0.66) mmol · l–1 with placebo;P<0.04]. The quotient lactate concentration/power (mmol · l–1 · W–1) also increased with caffeine at the end of pedalling [7.6 · 10–3 (SEM 3.82 · 10–5) vs 6.85 · 10–3 (SEM 3.01 · 10–5);P<0.01] and after 5 min of recovery [9.82·10–3 (SEM 4.28 · 10–5) vs 8.84 · 10–3 (SEM 3.58 · 10–5);P<0.02]. We concluded that caffeine increased bothW
max and blood lactate concentration. 相似文献
148.
Morawietz L Gehrke T Classen RA Barden B Otto M Hansen T Aigner T Stiehl P Neidel J Schröder JH Frommelt L Schubert T Meyer-Scholten C König A Ströbel P Rader ChP Kirschner S Lintner F Rüther W Skwara A Bos I Kriegsmann J Krenn V 《Der Pathologe》2004,25(5):375-384
After 10 years, loosening of total joint endoprostheses occurs in about 3 to 10 percent of all patients, requiring elaborate revision surgery. A periprosthetic membrane is routinely found between bone and loosened prosthesis. Further histomorphological examination allows determination of the etiology of the loosening process. Aim of this study is the introduction of clearly defined histopathological criteria for a standardized evaluation of the periprosthetic membrane. Based on histomorphological criteria and polarized light microscopy, four types of the periprosthetic membrane were defined: periprosthetic membrane of wear particle type (type I), periprosthetic membrane of infectious type (type II), periprosthetic membrane of combined type (type III), periprosthetic membrane of indifferent type (type IV). Periprosthetic membranes of 268 patients were analyzed according to the defined criteria. The correlation between histopathological and microbiological diagnosis was high (89%, p<0,001), the inter-observer reproducibility was sufficient (95%). This classification system enables a standardized diagnostic procedure and therefore is a basis for further studies concerning the etiology of and pathogenesis of prosthesis loosening. 相似文献
149.
Hannich HJ Hartmann U Lehmann Ch Gründling M Pavlovic D Reinhardt F 《Medical hypotheses》2004,63(1):21-25
Weaning a patient from mechanical ventilation is occasionally a difficult process complicated by the patient's emotional state. Anxiety, agitation, depression and other emotional disturbances can start a vicious circle between fear of losing breath and dyspnea that impairs the process of withdrawing ventilatory support. A biocybernetic loop model is suggested that integrates psychological variables (e.g., capacity of self-control, self-confidence, sense of self-efficacy) as important factors for a successful weaning. The paradigm of biofeedback is regarded as a suited approach to strengthen these psychological factors. It means the externalization of physiological functions especially of those from the autonomous nervous system so that a patient becomes aware of them. In the case of the ventilated patient, it is assumed that the transformation of the respiratory activities into perceptible (acoustic and visual) signals supports the patient's self-controlling behaviour during the weaning process. He gets positive reinforcement for his efforts to influence his breathing intentionally and, by continuous and immediate information, he regains self-confidence to control his somatic functions effectively. The application of biofeedback is mainly described in single case studies. They all report a decrease in the respiratory rate and an increase in the tidal volume. The need for a controlled study is suggested that would answer the question of whether biofeedback is an appropriate psychological tool to facilitate the weaning process in mechanically ventilated patients. 相似文献
150.
Ch. Ell J. Braun H. J. König S. Domschke W. Domschke 《Journal of molecular medicine (Berlin, Germany)》1985,63(12):572-574
Summary The pharmacokinetics of high-dose metoclopramide (10 mg/kg body wt. in five infusions of 2 mg/kg body wt. each) was studied in 11 patients (5 females, 6 males) in two groups: group A with and group B (consisting of five patients) without forced diuresis. When the drug was infused, forced diuresis had no influence on the pharmacokinetics of metoclopramide (serum level after the 1st infusion was 851±361 ng/ml in group A versus 840±348 ng/ml in group B; after the 5th infusion it was 2,005±588 ng/ml in group A versus 2,463±1,350 ng/ml in group B). There were significant differences in the 24-h serum levels (582±308 ng/ml in group A versus 379±170 ng/ml in group B;P<0.05) and in the elimination half life (8.5±2.6 h in group A versus 6.1±1.1 h in group B;P<0.05). The results demonstrate that the dosage regimen originally suggested by Gralla for cytostatic drugs, with forced diuresis for high-dose metoclopramide therapy, may also be applied, with no dosage reduction, with to other cytostatic drugs which do not require forced diuresis. 相似文献