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991.
This project was designed to test two hypotheses drawn from a new formulation explaining the exaggerated winter birthrate among hospitalized schizophrenics. The first is that the supposed exaggerated winter birthrate among process schizophrenics actually represents a reduction in spring-fall births caused by prenatal exposure to infectious diseases during the preceding winter--i.e., a high prenatal death rate in process preschizophrenic fetuses. The second is that the level of negative symptoms in survivors at risk for schizophrenia who were born after winters with high infectious disease rates is exaggerated. The findings provided some tentative support for this formulation. Compared with counterparts born after low-disease winters, schizophrenics born after winters with high disease incidences tended to show lower (more reactive) scores on a measure of the process-reaction dimension but higher anhedonia scores.  相似文献   
992.
993.
CT evaluation of Crohn's disease: effect on patient management   总被引:8,自引:0,他引:8  
CT scans from 80 consecutive patients with clinically symptomatic Crohn's disease were reviewed retrospectively to determine the effect of CT diagnosis on patient management. The initial clinical impression and any subsequent change in patient management because of the CT findings were noted. In 22 (28%) of the 80 patients, significant previously unsuspected findings led to a change in medical or surgical management. These included 12 patients with fistulae, four with abscess, two with avascular necrosis of the femoral head, two with sacral osteomyelitis, and single cases of pelvic inflammatory disease and femoral vein thrombosis.  相似文献   
994.
Summary Bone loss and fracture type were determined in 358 tibial condylar fractures. Degree of osteoporosis at the knee was defined by analogy to Singh's grades of osteoporosis at the hip and to Jhamaria's classification of osteoporosis at the calcaneum: grade V — normal; grade IV — slight reduction of trabecular bone; grade III — osteoporosis, predominantly of trabecular bone; grade II — osteoporosis of trabecular and cortical bone. Five fracture types were distinguished, with the component of trabecular bone compression increasing from a to e: a — pure split fractures; b — split fractures with displacement of a piece of the articular surface; c — split compression fractures; d — local compression fractures; e — compression of a whole condyle. There was a highly significant rank correlation between the two sets of ordered categories. Fractures in osteoporotics tended to involve the lateral condyle; this is explained by the fact that crush fractures occurred more frequently at the lateral condyle. The influence of bone loss on fracture type was demonstrated to be independent of age. A clear understanding of these associations concerning three variables at a time was reached by the use of log-linear-model analysis for cross-classified qualitative data.
Zusammenfassung Bei 358 Frakturen der proximalen Tibia wurden der röntgenologisch erkennbare Knochenschwund und die Frakturform festgestellt. Entsprechend dem Singh-Index zur Bestimmung der Osteoporose am proximalen Femur und der Klassifikation der Trabekelstruktur am Fersenbein nach Jhamaria wurden folgende Osteoporosegrade am Knie definiert: Grad V — normal, Grad IV — Spongiosastruktur leicht vermindert, Grad III — Osteoporose betrifft vorwiegend die Spongiosa, Grad II —Osteoporose von Spongiosa und Kompakta. Fünf Frakturformen wurden unterschieden, wobei das Ausmaß der Spongiosakompression von a bis e ansteigt: a — reine Spaltfrakturen, b — Spaltfrakturen mit Abscherung eines Gelenkflächenteiles, c —Spaltkompressionsfrakturen, d — Frakturen mit lokaler Kompression, e — Frakturen mit Kompression eines ganzen Kondyls. Zwischen diesen beiden Merkmalen, deren Ausprägungen Rangklassen bilden, war eine hochsignifikante Rangkorrelation nachzuweisen. Brüche osteoporotischer Knochen betrafen vermehrt den lateralen Gelenksknorren, was dadurch statistisch zu erklären war, daß dieser sich für Kompressionsfrakturen als anfälliger erwies. Die Beziehung zwischen Osteoporose und Frakturform war nicht abhängig vom Lebensalter. Solche Zusammenhange zwischen je drei Variablen konnten übersichtlich dargestellt wurden, indem die Häufigkeitstabellen durch Log-lineare Modelle interpretiert wurden.
  相似文献   
995.
A cross-sectional study of tobacco-smoking habits in a random sample of 976 coloured subjects aged 15-64 years revealed that smoking was common, 57% of men and 41% of women being current smokers and 10.4% of men and 9.6% of women having stopped smoking. Heavy smoking prevailed, indicating by mean daily consumption of 14.2 and 13.1 cigarettes among male and female smokers respectively; only 33.5% of male and 39.6% of female smokers used less than 10 cigarettes per day. Coloured smokers smoked more heavily during the weekend. Both men and women smoked mostly filter cigarettes. Forty-four per cent of male and 49.5% of female smokers stated that they had attempted to stop smoking, mainly for health reasons. More than one-third of the participants had a positive attitude to combating smoking, particularly those with an educational level higher than Standard 7. Former smokers and heavy smokers had a significantly higher prevalence of ischaemic heart disease than the other participants. Smoking was associated with a low body mass index, low high-density lipoprotein cholesterol levels, low socio-economic standing, high alcohol consumption and type A coronary-prone behaviour in men. In 1982 the economically active coloured population of the Cape Peninsula spent an estimated R36.2 million on cigarettes.  相似文献   
996.
This study compares the weight of the human brain to gestational age and body dimensions. A new formula for calculating the rate of growth is proposed. It consists of a second order polynomial function: Y = A0 + A1X + A2X2, in which Y is brain weight, body weight, height, or body surface area; X is gestational age in weeks and A0, A1, and A2 are statistically estimated coefficients. In utero, the growth rate is most rapid for body weight, followed in decreasing order by brain weight, body surface area, and height. Brain growth is the same for both sexes in black and white races; it accelerates between the 20th and 45th weeks of gestation. The size of the newborn infant brain is directly related to gestational age and body size and is not determined by sex or race.  相似文献   
997.
998.
Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction.  相似文献   
999.
Fifteen patients with cutaneous signs and symptoms caused by adverse reactions to foods were treated in an open trial with ketotifen for 4 to 6 weeks. Seven subjects were allergic and 8 had food intolerance. Each patient was treated with a single dose of ketotifen daily: 2 mg half an hour before going to sleep. Clinical improvement was achieved in 6 out of 7 allergic patients and in 6 out of 8 patients with food intolerance. Since several drugs have been demonstrated to have an influence on immune response, the in vitro effects of ketotifen on some immunological parameters were also studied. Ketotifen showed a significant inhibitory effect on autologous mixed lymphocyte reaction responsiveness.  相似文献   
1000.
Aseptic bone necrosis is a well known complication after corticosteroid treatment in adults and several hundred cases have been reported. Alterations in fat metabolism with vascular occlusion due to fat embolization, as well as microtraumata and osteoporosis are discussed as etiologic factors. In contrast, aseptic bone necrosis in relation to corticosteroid treatment is rare in children and adolescents. We therefore report 3 patients, aged from 10 to 18 years, suffering from severe aplastic anemia, meningeal relapse after acute lymphocytic leukemia and acute myelocytic leukemia respectively, who developed aseptic bone necrosis 6, 11, and 20 months following the onset of corticoid therapy. The patients survive from 28+ to 50+ months after diagnosis of their initial hematologic disease, as it can be expected today for increasing numbers of patients. We therefore believe, that aseptic bone necrosis may represent a serious therapy related complication and suggest that, diagnostic examination in patients with suspicious complaints of the hip, shoulder or knee should also exclude the possibility of a bone necrosis after leucemic relapse has been ruled out. Since radiological changes only develop several weeks to months after the onset of the clinical symptoms and because of the disabling consequences for patients, misdiagnosed at the beginning, a 99 technetium bone scan should be done as early as possible. Corticosteroids, despite their serious side effects are still being considered as a important part of hematologic therapy and are not being omitted in the near future, so that the earliest possible diagnosis of bone necrosis will remain of great importance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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