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151.
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RP Fule 《Canadian Metallurgical Quarterly》1997,51(7):221-225
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G Pantaleo H Soudeyns JF Demarest M Vaccarezza C Graziosi S Paolucci MB Daucher OJ Cohen F Denis WE Biddison RP Sekaly AS Fauci 《Canadian Metallurgical Quarterly》1997,27(12):3166-3173
Down-regulation of the initial burst of viremia during primary human immunodeficiency virus (HIV) infection is thought to be mediated predominantly by HIV-specific CD8+ cytotoxic T lymphocytes (CTL). This response is associated with major perturbations in the T cell receptor (TCR) repertoire. To investigate the failure of the cellular immune response to adequately control viral spread and replication and to prevent establishment of HIV infection, changes in the TCR repertoire and in the distribution of virus-specific CTL between blood and lymph node were analyzed in three patients with primary infection. By the combined use of clonotype-specific polymerase chain reaction and analysis of the frequency of in vivo activated HIV-specific CTL, it was shown that HIV-specific CTL clones preferentially accumulated in blood as opposed to lymph node. Accumulation of HIV-specific CTL in blood occurred prior to effective down-regulation of virus replication in both blood and lymph node. These findings should provide new insights into how HIV, and possibly other viruses, elude the immune response of the host during primary infection. 相似文献
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Studies on rats maintained on low-protein-calorie diets during the lactation period show that food intake decreases. This process results in weight loss and a delay in litter development. The purpose of the present study was to determine the alterations in food intake, maternal weight and litter growth during lactation when dams were exposed to diets with different levels of protein and carbohydrate. Female Wistar rats receiving one of 4 different diets, A (N = 14), B (N = 14), C (N = 9) and D (N = 9), were used. Diet A contained 16% protein and 66% carbohydrate; diet B, 6% protein and 77% carbohydrate; diet C, 6% protein and 66% carbohydrate; diet D, 16% protein and 56% carbohydrate. Thus, C and D diets were hypocaloric, while A and B were isocaloric. The intake of a low-protein diet in groups B and C affected the weight of dams and litters during the last two weeks of lactation, while the low-calorie diets limited the growth of D litters at 21 days compared with A litters, but had no effect on the weight of D dams. Group B showed an increase in intake during the first five days of lactation, resulting in a behavioral calorie compensation due to the increase in carbohydrate content, but the intake decreased during the last part of lactation. Food intake regulation predominantly involves the recruitment of a variety of peripheral satiety systems that attempt to decrease the central feeding command system. 相似文献
157.
Fifty patients of various types of cerebral palsy were studied to find out an association between cerebral palsy, EEG abnormalities and development quotient. Seventy-six per cent patients had spastic cerebral palsy. Hypotonic cerebral palsy was the next common type (14%). Athetosis and ataxic forms were found to be rare (2% each). Epilepsy was associated with 56% patients. Clinical types of seizures observed were: Generalised tonic-clonic (43%), myoclonic (17.9%), generalised tonic (10.7%), partial simple (10.7%) and partial complex (17.9%). The incidence of seizures was highest in hypotonic type in which 85.7% had epilepsy. Mean developmental quotient of cerebral palsy patients was 34.9% with maximum retardation in hypotonic cerebral palsy (25.14%). Sixty per cent of patients had abnormal EEG, out of these hypotonic patients had maximum (70%) chances of EEG abnormality followed by spastic patients (55%). Developmental retardation was more severe statistically in the patients with abnormal EEG than normal EEG. 相似文献
158.
GL Fraser P Stogsdill JD Dickens DE Wennberg RP Smith BS Prato 《Canadian Metallurgical Quarterly》1997,157(15):1689-1694
BACKGROUND: Although numerous reports have described interventions designed to influence antibiotic utilization, to our knowledge none have been evaluated in a randomized study. METHODS: Adult inpatients receiving 1 or more of 10 designated parenteral antibiotics for 3 or more days during a 3-month period were randomized to an intervention (n = 141) and a control (n = 111) group using an unblocked, computer-generated random number table. Obstetric patients and those seen in infectious disease consultation were excluded. The intervention group received antibiotic-related suggestions from a team consisting of an infectious disease fellow and a clinical pharmacist. Both groups were evaluated for clinical and microbiological outcomes as well as antibiotic utilization via prospective chart reviews and analysis of the hospital's administrative database. RESULTS: Sixty-two (49%) of the intervention group patients received a total of 74 suggestions. Sixty-three (84%) of these suggestions were implemented; the majority involved changes in antibiotic choice, dosing regimen, or route of administration. Per patient antibiotic charges were nearly $400 less in the intervention group vs controls (P = .05). Almost all the savings were related to lower intravenous antibiotic charges. Clinical and microbiological response, antibiotic-associated toxic effects, in-hospital mortality, and readmission rates were similar for both groups. Multiple linear regression analysis identified randomization to the intervention group and female sex as the sole predictors of lower antibiotic charges. There was a trend toward a shorter length of stay for the intervention group (20 vs 24.7 days, P = .11). CONCLUSIONS: This is the first randomized study to evaluate whether antibiotic choices can be influenced in a cost-effective fashion without sacrificing patient safety. We demonstrate that 50% of patients initially treated with expensive parenteral antibiotics can have their regimens refined after 3 days of therapy and that these modifications result in good clinical outcomes with a substantial reduction in antibiotic expense. 相似文献
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O Fernandes RP Souto JA Castro JB Pereira NC Fernandes AC Junqueira RD Naiff TV Barrett W Degrave B Zingales DA Campbell JR Coura 《Canadian Metallurgical Quarterly》1998,58(6):807-811
Traditional molecular and biochemical methods, such as schizodeme analysis, karyotyping, DNA fingerprinting, and enzyme electrophoretic profiles, have shown a large variability among Trypanosoma cruzi isolates. In contrast to those results, polymerase chain reaction (PCR) amplification of sequences from the 24S alpha ribosomal RNA gene and from the mini-exon gene nontranscribed spacer indicated a dimorphism among T. cruzi isolates, which enabled the definition of two major parasite lineages. In the present study, 86 T. cruzi field stocks (68 isolated from humans with defined presentations of Chagas' disease and 18 from triatomines) derived from four Brazilian geographic areas were typed by the PCR assay based on the DNA sequences of the mini-exon and 24S alpha rRNA genes. These stocks were ordered into the two major T. cruzi lineages. Lineage 1 was associated mainly with human isolates and lineage 2 with the sylvatic cycle of the parasite. 相似文献