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41.
In a West African urban community, measles infection in infants was examined over 5 years (1979-1983). In the age group 0 to 11 months, measles mortality was higher among secondary cases (infected in the house) than among index cases (infected outside the house), and the proportion of secondary cases was significantly higher for this age group than for older children. Intensive exposure related to the social pattern of disease transmission may be important in explaining the high infant mortality observed with measles in developing countries. Mortality during the first 12 months of life increased with age, presumably because of the decrease of maternally derived measles antibodies. In children younger than 6 months of age, who are usually considered to be protected by maternal antibody, intensive exposure may lead to infection, as demonstrated by a high level of measles-specific antibodies in some children exposed to an older sibling with measles. The aim of public health policies should be to change conditions of exposure.  相似文献   
42.
This retrospective cohort study examines the relationship between changing pregnancy-smoking behaviors, from the first to the second pregnancy, on second-pregnancy rates of small for gestational age (SGA) neonates. Electronic birth records provided data on 5107 pregnant women who had two singleton births in Kansas City, MO, from 1994 to 2003. Pregnancy-smoking behavior was classified by smoking status (nonsmoker [NS] or smoker [SMK]) during the first (previous)/second (current) pregnancy: NS/NS, NS/SMK, SMK/SMK, and SMK/NS. The overall second-pregnancy SGA rate was 6.7% and varied with pregnancy-smoking behavior: 5.9%, NS/NS; 6.6%, SMK/NS; 12.5%, NS/SMK; and 12%, SMK/SMK; P < 0.001 Current pregnancy-smoking was associated with increased odds ratio (OR) of SGA; SMK/SMK (OR, 2.80; 95% confidence interval [CI], 2.00 to 3.93) versus NS/SMK (OR, 1.83; 95% CI, 1.19 to 2.82) versus SMK/NS (OR, 1.31; 95% CI, 0.65 to 2.65) versus NS/NS (OR, 1.00; 95% CI, reference). Being black (OR, 3.73; 95% CI, 2.91 to 4.79) and having medical risk factors (OR, 1.31; 95% CI, 1.09 to 1.74) also were significantly associated with a SGA neonate in second pregnancy. In conclusion, risk of delivering a SGA neonate in a current pregnancy is related to current rather than previous pregnancy-smoking. Therefore, antismoking socialization during pregnancy should focus on preventing and stopping current pregnancy-smoking, irrespective of past behavior.  相似文献   
43.
Zusammenfassung In Untersuchungen am Kaninchen wird gezeigt, daß durch Einspritzung von Bakterienstoffen eine Leukocytose mit Auftreten von jodophilen Leukocyten im Blut hervorgerufen werden kann. Die Menge der jodophilen Zellen ist proportional der Menge der einwirkenden Bakterienstoffe. Gleichsinnige Beobachtungen wurden auch am Menschen gemacht.Durch zentralnervöse Reizung (Luftfüllung der Hirnventrikel) werden hochgradige Leukocyten ausgelöst, ohne daß dabei eine Jodophilie der Leukocyten zustande kommt.Diezentralnervöse Reizung, so auch die zentralnervöse Reizung durch Bakterienstoffe, führt zu einer Bereitstellung von Leukocyten im Sinne einer Abwehrreaktion, zu einer Leukocytose. Hiervon zu trennen ist diehumorale Einwirkung der Bakterienstoffe auf die Leukocyten. Die Jodophilie ist eine Reaktion der Leukocyten auf die humorale Einwirkung der Bakterienstoffe, sie stellt eine Stoffwechseländerung innerhalb der Leukocyten infolge dieser Einwirkung der Bakterienstoffe dar.  相似文献   
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A perfect serologic test for infection with Trypanosoma cruzi does not exist. This study uses recombinant T. cruzi surface proteins in the antibody capture enzyme linked immunoabsorption assay (ELISA); and compares this approach to the more standard immunofluorescence assay (IFA). Three recombinant antigens are studied: F1-160 corresponding to the 160 kDa flagellar associated surface protein of trypomastigotes (the motile form of T. cruzi in mammalian infections); and SA 85-1.1 and 1.2 corresponding to different members of the 85 kDa family of surface proteins expressed by trypomastigotes and amastigotes (the replicative, non-motile form of T. cruzi in mammalian infections). Each recombinant antigen is found to be highly specific (range 86-94%) but relatively insensitive (range 36-52%) when used to screen for antibodies to T. cruzi. Defining seropositivity as reactivity to any of the three recombinant antigens markedly increases the sensitivity (72%) with only a minor reduction in specificity (82%). Thus, employing recombinant T. cruzi antigens to screen for T. cruzi infection has promise, but improvements in sensitivity must be made before widespread utilization is recommended.  相似文献   
46.
Colonoscopy was offered to 206 first-degree relatives of 181 patients operated on for colorectal cancer (CRC). Findings of polyps in relatives correlated with Dukes staging, extent of dedifferentiation and localization of tumour in the operated patient, and type of family relationship. Adenomas in relatives and Dukes staging of carcinoma in the patients were inversely related. Relatives of patients with Dukes stage A tumour had more than twice as many adenomas as and a higher prevalence of multiple adenomas than relatives of patients with advanced cancer at the time of operation. If the patient had polyp(s) in addition to tumour, the number of adenomas per relative was almost doubled. Hyperplastic polyps in relatives were associated with poorly differentiated carcinoma in their related patients. These results support the theory that not all CRC are derived from polyps and that adenoma-derived CRC may have a better prognosis than 'de novo' CRC. An adenoma prevalence risk table is also presented.  相似文献   
47.
This study compared external insulin pump treatment using insulin lispro or insulin aspart with multiple daily injections (MDI; four or more injections per day) using insulin glargine and insulin lispro or insulin aspart. An electronic database was used to retrieve various parameters of glycemic control for 515 adult patients with type 1 diabetes. An insulin pump was used by 216 patients, and 299 patients were taking insulin glargine for at least 6 months. The mean age (approximately 33 years), duration of diabetes (approximately 16 years), and duration of treatment (approximately 12 months) were similar for both the pump and insulin glargine groups. The mean (+/-SEM) A1C values were significantly reduced in both groups from the baseline to the end of the study (7.7 +/- 0.1% to 7.5 +/- 0.1% for the pump group and 8.0 +/- 0.1% to 7.7 +/- 0.1% for the insulin glargine group, P< 0.001) with similar weight gain (P> 0.05) in both groups. The insulin glargine group significantly reduced basal insulin intake at follow-up. The premeal boluses were similar throughout the study for both groups. The subjects reporting severe hypoglycemic episodes were similar in the two groups; however, there were 12 cases of diabetic ketoacidosis reported in the pump group and none in the insulin glargine group. Patients with type 1 diabetes can achieve similar glycemic control using insulin glargine with premeal insulin lispro or by using an external infusion pump with insulin lispro or insulin aspart. However, costs and episodes of diabetic ketoacidosis are significantly higher for insulin pump users.  相似文献   
48.
When it comes to clinical survival trials, regulatory restrictions usually require the application of methods that solely utilize baseline covariates and the intention‐to‐treat principle. Thereby, much potentially useful information is lost, as collection of time‐to‐event data often goes hand in hand with collection of information on biomarkers and other internal time‐dependent covariates. However, there are tools to incorporate information from repeated measurements in a useful manner that can help to shed more light on the underlying treatment mechanisms. We consider dynamic path analysis, a model for mediation analysis in the presence of a time‐to‐event outcome and time‐dependent covariates to investigate direct and indirect effects in a study of different lipid‐lowering treatments in patients with previous myocardial infarctions. Further, we address the question whether survival in itself may produce associations between the treatment and the mediator in dynamic path analysis and give an argument that because of linearity of the assumed additive hazard model, this is not the case. We further elaborate on our view that, when studying mediation, we are actually dealing with underlying processes rather than single variables measured only once during the study period. This becomes apparent in results from various models applied to the study of lipid‐lowering treatments as well as our additionally conducted simulation study, where we clearly observe that discarding information on repeated measurements can lead to potentially erroneous conclusions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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50.
Clinical studies involving 5-azacytidine, a ring analogue of cytidine, began in Europe in 1967 and the United States in 1970, and we review available preclinical and clinical studies here. The drug possesses cytotoxic, antimicrobial, antineoplastic, abortive, and mutagenic activity in various biological systems. 5-Azacytidine is thought to exert its antineoplastic effect through interference with nucleic acid metabolism. The dose-limiting toxicities are nausea, vomiting, and leukopenia, while the incidence of thrombocytopenia is low. Hepatic toxicity ranges from abnormal findings in liver function tests to hepatic coma. Clinical results in solid tumors are not encouraging, but 5-azacytidine shows consistent antitumor activity in patients with acute myelogenous leukemia resistant to previous treatment. An overall response rate of 36%, with 20% complete remissions, was achieved in 200 previously treated patients with acute myelogenous leukemia. Further studies must define the role of 5-azacytidine alone and in combination for the first-line treatment of acute myelogenous leukemia.  相似文献   
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