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排序方式: 共有191条查询结果,搜索用时 15 毫秒
91.
FE McCutchan JK Carr M Bajani E Sanders-Buell TO Harry TC Stoeckli KE Robbins W Gashau A Nasidi W Janssens ML Kalish 《Canadian Metallurgical Quarterly》1999,254(2):226-234
Multiple human immunodeficiency virus type 1 (HIV-1) genetic subtypes, intersubtype recombinants, and group O have been found in west central Africa. In Nigeria, where HIV-1 prevalence is rising rapidly, characterization of HIV-1 strains has been limited. Each of three full-length genome sequences acquired to date shows evidence of recombination: two are largely subtype G with subtype A segments in the midgenome accessory region; the third, IbNG, is subtype G with the long terminal repeats and two segments of pol from subtype A. In this study, peripheral blood mononuclear cells obtained in 1994-1995 from 10 patients hospitalized in northeastern Nigeria were evaluated by sequencing of the complete envelope and, from 7 patients, a portion of gag. Four patients harbored subtype G viruses and six patients had recombinant viruses. Two had strains sharing the A/G recombinant structure of IbNG. Two had a previously undescribed recombinant, mostly subtype A, whose carboxyl-terminal gp41 could not be classified. An A/G recombinant different from IbNG but similar to CA1, a Cameroonian strain, was found in one patient. The remaining patient had a strain that was otherwise subtype G but shared an unclassified carboxyl-terminal gp41 segment with the CA1-like strains. Other subtypes and group O were not found. 相似文献
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A comparison of 10 and 14 days of lansoprazole triple therapy for eradication of Helicobacter pylori
MB Fennerty TO Kovacs R Krause M Haber A Weissfeld N Siepman P Rose 《Canadian Metallurgical Quarterly》1998,158(15):1651-1656
BACKGROUND: Data from large, multicenter, US studies determining the efficacy of triple therapy for the eradication of Helicobacter pylori are lacking, especially for a treatment duration of less than 14 days. METHODS: Patients with H pylori infection and active duodenal ulcer disease or a history of duodenal ulcer disease within the past year were randomized to receive 30 mg of lansoprazole, 1 g of amoxicillin, and 500 mg of clarithromycin twice daily for 10 or 14 days. The primary efficacy end point was the eradication of H pylori as confirmed by negative histological and culture results at 4 to 6 weeks after the completion of treatment. RESULTS: Of 284 patients enrolled in the study from 46 US sites, 236 met the entry criteria. At 4 to 6 weeks after the end of therapy, H pylori was eradicated in 85% (96/ 113) of the patients receiving 14-day triple therapy and in 84% (103/123) of those receiving 10-day triple therapy by per-protocol analysis (95% confidence interval for treatment group differences, -10.5 to 8.1; P>.05). There was also no significant difference between the 14- and 10-day treatment groups when analyzed by an intent-to-treat analysis of H pylori eradication. A similar proportion of patients in each treatment group reported an adverse event related to therapy (34% [46/136] vs 38% [56/148], respectively). CONCLUSIONS: In patients with an active or a recent history of duodenal ulcer, lansoprazole-based triple therapy for 10 or 14 days is highly effective in the eradication of H pylori. The duration of therapy may be reduced from 14 to 10 days without a significant effect on regimen efficacy. 相似文献
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Alzheimer's disease (AD) is a slowly progressing neurodegenerative disease characterized by the loss of neurons and formation of amyloid plaques, often surrounded by reactive astrocytes. Astrocytes are important regulators of the normal neuronal environment, and changed astrocyte function may lead to increased neuronal vulnerability. The slow onset of the disease with a gradual increase in the beta-amyloid peptide (beta-AP) concentrations may alter astrocyte function long before any visible symptoms of the disease are observed. We, therefore, studied in vitro the effects of small amounts of beta-AP(1-40) and -(25-35) on rat cortical astrocyte function observing changes in cell morphology, intracellular calcium levels (Cai), and ion channel activity. Incubation with 10 and 200 nM beta-APs caused increased process formation and hypertrophy. Stellation was also detected when astrocyte cultures were incubated with 1 microM AlCl3 alone, or together with beta-APs. Fura-2AM-loaded astrocytes were used to test whether the morphological changes were connected to changes in Cai levels. 1 microM beta-AP(1-40) induced transient Cai increase in approximately 17%, and beta-AP(25-35) in approximately 36% of astrocytes. In patch-clamp studies, increased K+ and Cl- channel activity was detected with 10-100 nM beta-AP(1-40). With large amounts (20 microM) of beta-AP(1-40), an additional giant channel activity emerged. These beta-AP-induced changes in astrocyte function may eventually be critical for the neuronal survival in Alzheimer's disease. 相似文献
98.
T Vanderah AE Takemori M Sultana PS Portoghese HI Mosberg VJ Hruby RC Haaseth TO Matsunaga F Porreca 《Canadian Metallurgical Quarterly》1994,252(2):133-137
A total of 78 patients with superficial bladder carcinoma were prospectively randomized to two groups following complete transurethral resection (TUR). Each received 12 intravesical instillations of 10(7) units interferon A or 120 mg BCG Connaught for 1 year starting 6 weeks post-TUR. After a mean observation period of 24 (13-31) months in the BCG and 25 (6-32) months in the IFN group 5/32 (15.6%) recurrences in the BCG versus 21/35 (60%) in the IFN group were observed (P = 0.0003). In the IFN group 18.4% of the patients had dysuria and 2.6% fever; in the BCG group 35% had fever, 60% cystitis, 1 patient granulomatous epididimoorchitis and 1 patient pneumonitis with granulomatous prostatitis. With our instillation regimen interferon A had few side effects but also no prophylactic effect, whereas BCG had tolerable-seldom severe--side effects and was very effective in preventing recurrences. Perhaps IFN should be given earlier after TUR and in a higher dosage. 相似文献
99.
Cot death is the most important cause of death during the first year of life after the newborn period in Norway. A case control study was performed by sending questionnaires to 188 cot death parents and 475 control parents with infants matched for age, sex and time of birth. 76% of the cot death parents and 79% of the control parents completed the questionnaires. The male/female ratio of the babies in both groups was 64/36. The age distribution showed a peak between two and four months. 65% succumbed during the winter months. During the winter 32% died outdoors. This was true for only 16% of those who died during summer. A higher proportion of the cot death cases than the controls were premature (more than eight weeks). 78% of the cot death victims usually slept prone, whereas this was true for only 50% of the controls (p < 0.01). 91% of the cot death victims were found dead in a prone position. When comparing live babies during the first three months of life, significantly more cot death mothers than control mothers had stopped breastfeeding. A larger proportion of the cot death victims than the controls had had apparent life threatening events (p < 0.01). Foam mattresses were equally frequent in both groups. 相似文献
100.
TO Nelson 《Canadian Metallurgical Quarterly》1993,122(2):269-273
OBJECTIVE: The aim was to determine whether cocaine has a direct effect on the myocardium which is independent of coronary vasospasm. METHODS: Cocaine was introduced into the perfusate of the isolated rabbit ventricular septal preparation in the concentration range 10(-5) to 10(-3)M while holding coronary flow of oxygenated Krebs solution constant at 3.0 ml.min-1 by a perfusion pump. The septa were obtained from white male New Zealand rabbits and were paced at 48 beats.min-1. Mechanical and enzymatic measurements were performed. RESULTS: Developed tension (T), maximum contraction velocity (+dT/dt), and maximum relaxation velocity (-dT/dt) were all depressed to approximately the same degree at each different cocaine concentration and averaged 4, 48, and 95% at 10(-5), 10(-4), and 10(-3)M cocaine respectively, with an ED50 = 9 x 10(-5)M. Relaxation time (tR/T) was prolonged, but the ED50 was greater (by 1.5 times) than for the other mechanical parameters. Simultaneously, an increase in excitation threshold dysrhythmia developed which resulted in 17, 50, and 90 beats missed per 100 stimulations at 10(-5), 10(-4), and 10(-3)M cocaine respectively. Resting tension (RT) was not altered. Coronary flow rate was not reduced in presence of cocaine because of the constant delivery pump. T, +dT/dt, -dT/dt and modulation of the excitation threshold completely recovered after washout of cocaine. CONCLUSIONS: Cocaine has acute direct, though reversible, depressant effects on the myocardium, including depression of function and modulation of excitation threshold, which are independent of its effect on coronary flow. 相似文献