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91.
H W Bruckner C J Cohen J D Goldberg B Kabakow R C Wallach G Deppe E M Greenspan S B Gusberg J F Holland 《Cancer》1981,47(9):2288-2294
In a prospective controlled randomized trial, patients with advanced ovarian carcinoma (FIGO Stage III or IV) were treated with cis-diamminedichloroplatinum (II), (DDP), alone, DDP and Adriamycin (ADM), or Triethylenethiophosphoramide (ThioTEPA) and methotrexate (MTX). DDP alone produces objective responses in 31% of evaluable patients, ThioTEPA and MTX in 36%. The combination of DDP and ADM produces the best response rate, 80% (.01 less than P less than 0.25). The risk of progression or death is substantially reduced for the two DDP regimens combined when compared with ThioTEPA-MTX (P = .03). Multivariate analysis further suggests the superiority of the two DDP regimens because poorly differentiated tumors and large, greater than 2 cm, residual tumors failed to produce their usual adverse effect on prognosis when patients were treated with the two DDP regimens. Patients with poorly differentiated tumors or tumors of unknown grade treated with platinum or DDP-ADM experienced better survival than similar patients treated with ThioTEPA (P = .01). 相似文献
92.
93.
Braman JP Bruckner JD Clark JM Norman AG Chansky HA 《Clinical orthopaedics and related research》2005,(430):202-207
We tested the hypothesis that articular cartilage adjacent to experimental osteochondral defects is not subject to unusual strains under load. A 2.5-mm drill hole was made in the medial femoral condyle of 15 knees from 10 adult rabbits. Experimental joints were loaded with simulated quadriceps force, then frozen under load and preserved by freeze-substitution fixation. Deformation in the region of the defect was evaluated by scanning electron and light microscopy and compared with nondrilled and nonloaded control knees. To simulate blood clot, alginate was placed into some defects before loading. In loaded knees, articular cartilage at the edge of the drill hole was abnormally flattened and folded into the defect. Opposing tibial cartilage or meniscus intruded into the femoral defect beyond the cement line. Alginate did not prevent incursion of opposing cartilage. In this standard drill-hole model, the articular cartilage defect is occupied by the opposing surface when a joint is loaded. Any tissue growing or surgically implanted in the defect is subject to loading and displacement, therefore complicating attempts to characterize the healing or regenerative potential in similar drill-hole models. Deformation of cartilage at the defect edge suggests load concentration or increased compliance. Either phenomenon would contribute to subsequent degeneration of the cartilage adjacent to defects. 相似文献
94.
Literature describing environmental influences on human conception and gestation implies that the ratio of male to female live births should vary positively over time with the population's ability to produce and distribute goods and services. No direct test of this hypothesis appears in the literature despite its apparent importance in understanding the biological implications of collective choices. We offer a test based on Swedish data for the years 1862 through 1991. The results support the hypothesis. We argue that the findings have implications for basic science as well as for the debate over the biological effects of social policy. 相似文献
95.
Fetal death sex ratios: a test of the economic stress hypothesis 总被引:1,自引:0,他引:1
BACKGROUND: The ratio of male to female live births (i.e. the sex ratio) reportedly falls when populations suffer rare and extreme ambient stressors such as the collapse of national economies. This association has been attributed to the death of male fetuses and to reduced conception of males. We assess the validity of the first of these mechanisms by testing the hypothesis that the fetal death sex ratio varies positively over time with the unemployment rate. Using the unemployment rate also allows us to determine if ambient economic stressors less extreme than collapsing national economies affect the fetal death sex ratio. METHODS: We test our hypotheses by applying time-series methods to monthly counts of fetal deaths and the unemployment rate from the state of California beginning January 1989 and ending December 2001. The methods control for trends, seasonal cycles, and other forms of autocorrelation that could induce spurious associations. RESULTS: Results support the fetal death mechanism in that male fetal deaths increased above the values expected from female deaths and from history in months in which the unemployment rate also increased over its expected value. CONCLUSIONS: Our findings suggest that ambient stressors as common as increasing unemployment elevate the risk of fetal death among males. We discuss the social, economic, and health costs borne by parents and communities afflicted with these fetal deaths. 相似文献
96.
Background
BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.Methods
114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.Results
All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.Conclusions
Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy 相似文献97.
98.
Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献
99.
Computed tomographic appearance of the bulging annulus 总被引:6,自引:0,他引:6
100.
The pharmacokinetics of pentobarbital, 30mg/kg iv, were studied in untreated rats and rats pretreated with 1,5, and 25 ppm of polychlorinated biphenyls in food for up to 140 days. Environmental contaminants may contribute to variations in metabolic rates of drugs by causing enzyme induction. The objective of this work was to quantitate the effects of environmental levels of the contaminant and enzyme inducer, a polychlorinated biphenyl, on the pharmacokinetics of pentobarbital, a drug whose primary elimination route is liver metabolism. The pharmacokinetics of pentobarbital in rats could be fit to a biexponential equation of the type Cp = Ae-alpha t+ Be-beta t. After 35 days of pretreatment, only the 25-ppm-treated rats showed any significant acceleration of pentobarbital elimination. At the 70- and 140-day samplings, both the 5- and 25-ppm pretreatments showed significant acceleration of pentobarbital elimination. There were no significant effects on A, alpha, B, and Vd for any pretreatment. The beta-values for the 25-ppm-pretreated rats reached a constant value from the 35-day pretreatment period onward. A calculation of total body clearance suggested that pentobarbital elimination in those rats had approached portal blood flow rate-limited metabolism. 相似文献