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1.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.  相似文献   
2.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
3.
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed.  相似文献   
4.
Rigor and resistance to stretch in vertebrate smooth muscle   总被引:2,自引:0,他引:2  
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Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
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Summary The pharmacokinetics of cis-dichlorodiamminoplatinum (II) (cisplatin) have been studied in seven patients, of whom four received the drug as a one hour infusion and three received it as a 20 h infusion. The patients receiving the drug over one hour exhibited biphasic clearance of total platinum with a rapid initial phase (8.7–22.5 min) and a prolonged second phase (30.5–106 h). Free (ultrafilterable) cisplatin was readily detectable in this group and was rapidly cleared (half-life about 22 min). The volume of distribution of the drug was 50.3–65.6 liters and it was 26.6–50% excreted in the urine in 48h. In the patients receiving the 20 h infusion, a more complex plasma elimination curve was seen, with the appearance of a secondary peak. Free drug was not detectable in these patients and they showed less urinary excretion (21.4–25.9% at 48 h) than the one hour group. Cisplatin was bound to several plasma proteins, including albumin, transferrin, and -globulin. The data indicate that cisplatin is retained in the body more extensively after a 20 h infusion than after a one hour infusion.  相似文献   
10.
Surgical resection offers distinct theoretical advantages as the "local" modality in treatment of Stage I and II small cell carcinoma of the lung. We have treated 10 such patients by initial resection since 1975; all survivors but one received adjuvant chemotherapy for the full course thereafter. One patient died of a pulmonary embolus; the other nine remain without evidence of disease from 7 to 69 months after resection. A trial was undertaken of extended indications for resection in selected patients with Stage III-M0 disease. Criteria for patient selection have been developed gradually; these exclude patients for reasons of refusal, physiological inadequacy, disease unsuited to gross total eradication, or lack of adequate initial response to chemotherapy. Of six patients who survived the exclusion criteria and underwent resection, one has had a relapse at 26 months. All others remain without evidence of disease, 5 to 25 months after the start of treatment. We believe that systematic patient selection on the basis of defined criteria will identify a subset of patients having markedly improved chances for disease control. This group may represent as many as half of the patients first presenting with localized or MO disease. Patients excluded as candidates for resection have continued to receive standard nonsurgical combined-modality therapy.  相似文献   
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