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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 Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy.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.
Zusammenfassung Grundlagen Die pulmonale Thrombendarterektomie stellt eine effektive Therapie zur Behandlung von Patienten mit chronisch thromboembolischer pulmonalar Hypertonie dar. Wir berichten über unsere Erfahrungen mit dieser Operationstechnik bei den ersten 9 Patienten. Methodik Zwischen 1992 und Oktober 1994 wurde bei 9 Patienten eine pulmonale Thrombendarterektomie durchgeführt. über eine mediane Sternotomie wurden die Pulmonalarterien beider Seiten bis in ihre subsegmentalen Aufzweigungen im Sinne einer echten Endarterektomie vom organisierten thromboembolischen Material befreit. Zumeist waren Perioden des totalen Kreislaufstillstandes in tiefer Hypothermie notwendig, wobei diese zunehmend verkürzt werden konnten und 3 Patienten vollst?ndig ohne Kreislaufstopp operiert wurden. Ergebnisse Die perioperative Mortalit?t betrug 11%, wobei der 1. Patient am 14. postoperativen Tag an den Folgen eines Reperfusions?dems verstarb. Alle anderen Patienten sind 4 bis 22 Monate (im Mittel 13 Monate) nach dem Eingriff am Leben und zeigen eine Hochsignifikante Verbesserung ihrer h?modynamischen Situation (mean PAP pr?operativ: 62 mm Hg, postoperativ: 30 mm Hg p<0,001; Cardiac Index pr?operativ: 2,1 1/min/m2, postoperativ: 3,6 l/min/m2 p=0,001). W?hrend pr?operativ alle Patienten in NYHA-Klasse III oder IV waren, sind die 8 überlebenden jetzt alle in Klasse I oder II. Schlu?folgerungen Die pulmonale Thrombendarterektomie bietet eine erfolgreiche Therapiem?glichkeit für Patienten mit chronisch thromboembolischer pulmonaler Hypertonie mit einer in Anbetracht fehlender konservativer Altermativen akzeptablen Mortalit?t und ausgezeichneten funktionellen Langzeitergebnissen.   相似文献   
4.
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   
5.
6.
Hydranencephaly is defined as the replacement of a previously normal brain, in whole or in part, by membranous fluid-filled sacs. The etiology is not well understood, and the time course of development is unknown. Fifteen ovine fetuses were chronically cannulated and had both carotid arteries ligated at 100 days of gestation (term is 145–150 days). They were killed at 1 (n = 4), 2 (n = 6) and 4 (n = 5) weeks post-surgery, and the findings compared with those of 25 age-matched controls. By 2 weeks post-surgery the entire cerebral hemispheres and diencephalon had been replaced by fluid closely resembling cerebrospinal fluid. The choroid plexus, pituitary and brain stem remained outwardly normal, but the cerebellum showed signs of damage. Fetuses maintained normal values for blood gases and hematocrit up to 4 weeks post-surgery, and grew normally. Light microscopy of the brain stem showed significant losses of cell populations in the medulla by 4 weeks. Vascular casting and acute blood flow studies in an additional group of fetuses showed that the entire brain was perfused via the vertebral-occipital anastomosis immediately after acute bilateral carotid clamping, but that the blood flow rate was insufficient to maintain adequate oxygen delivery. Received: 4 August 1995 / Revised, accepted: 30 November 1995  相似文献   
7.
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
8.
In a radiologic search for embolized leaflets of Edwards-Duromedics bileaflet valves in 2 patients, the embolized fragments were localized in the iliac vessels using computed tomography. Sonography was successful in one case and standard X-ray films of the abdomen were negative in both cases.In vitro investigations with Björk-Shiley and Edwards-Duromedics leaflets suggested that standard X-ray films of the abdomen and pelvis should be considered as the first investigational technique. If negative, computed tomography of the lower abdomen should be done.  相似文献   
9.
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.  相似文献   
10.
BACKGROUND: Previous studies on semantic priming have suggested that schizophrenic patients with language disturbances demonstrate enhanced semantic and indirect semantic priming effects relative to controls. However, the interpretation of semantic priming studies in schizophrenic patients is obscured by methological problems and several artefacts (such as length of illness). We, therefore, used a psychometric high-risk approach to test whether healthy subjects reporting language disturbances resembling those of schizophrenics (as measured by the Frankfurt Complaint Questionnaire subscale 'language') display increased priming effects. In addition, the Schizotypal Personality Questionnaire was used to cover symptoms of schizotypal personality. Enhanced priming was expected to occur under conditions favouring automatic processes. METHODS: One hundred and sixty healthy subjects performed a lexical decision semantic priming task containing two different stimulus onset asynchronicities (200 ms and 700 ms) with two experimental conditions (semantic priming and indirect semantic priming) each. RESULTS: Analyses of variance revealed that the Frankfurt Complaint Questionnaire-' language' high scorers significantly differed from low scorers in three of the four priming conditions indicating increased automatic spreading activation. No significant results were obtained for the Schizotypal Personality Questionnaire total and subscales scores. CONCLUSIONS: In line with Maher and Spitzer it is suggested that increased automatic spreading activation underlies schizophrenia-typical language disturbances which in our study cannot be attributed to confounding variables such as different reaction time baselines, medication or length of illness. Finally, results confirm that the psychometric high-risk approach is an important tool for investigating issues relevant to schizophrenia.  相似文献   
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