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991.
This paper reviews seven cost-benefit estimates made in prevention studies published in peer-reviewed journal articles or peer-edited book chapters. This paper includes articles that examined prevention programs implemented on an individual level and programs that involved community coalitions, using both individual and environmental strategies. The studies showed considerable differences in approach both to prevention and to cost-benefit analyses. Increasing evidence exists that some prevention programs are effective, but the programs reported here also have demonstrated that they are cost-beneficial. The literature reveals that the savings per dollar spent ranged from $2.00 to $19.64. The variability in the range can be attributed to how costs were calculated, outcomes included, and differences in methodologies.  相似文献   
992.
Vertebral bone density in children: effect of puberty   总被引:12,自引:0,他引:12  
To determine changes in bone density during growth, trabecular vertebral density and an index of spinal cortical bone were measured with quantitative computed tomography in 101 children. The children were divided by age into three groups: prepubertal, indeterminate, and pubertal. Compared with prepubertal children, pubertal adolescents had significantly higher trabecular bone density and more compact bone in the spine (P less than .001). After controlling for puberty, vertebral bone density failed to correlate significantly with age, sex, weight, height, surface area, and body mass index. The results indicate that bone density increases markedly during puberty.  相似文献   
993.
报道了29个新的1-(1-取代苯基)-2-(1H-1,2,4-三唑或苯并三唑基)-O-(取代苄基)乙酮肟醚类化合物的合成与体外抗菌试验。结果表明,大多数化合物对大部分真菌有抑菌活性,化合物T1,T4,T6,T11,T12,B1,B3,B4和B6对部分真菌抑菌活性优于或相当于奥昔康唑。  相似文献   
994.
DSA in acute gastrointestinal hemorrhage: clinical and in vitro studies   总被引:3,自引:0,他引:3  
Selective intraarterial digital subtraction angiography (DSA) was used to examine 37 patients with acute gastrointestinal (GI) tract bleeding. Conventional screen-film angiography was used as an adjunct to DSA when a larger field of view was needed (five patients) and when bowel motion prevented the acquisition of adequate image quality with DSA (two patients). Conventional angiography was also performed in all cases in which there were negative DSA examinations. DSA reduced the mean examination time considerably (20% reduction overall), especially for cases involving embolization therapy (35% reduction). DSA was especially valuable in the upper GI tract, where it was used to rapidly locate and/or assist in the embolization of bleeding sites in 19 of 20 patients with positive angiograms. There were 12 true-negative DSA examinations and one false-negative examination due to the limited field of view (9 inches [22.9 cm]). Bowel and respiratory motion were not important problems in the upper GI tract. In the lower GI tract, the usefulness of DSA was severely limited by the small field of view and the misregistration artifact caused by bowel motion. In an in vitro study, DSA and conventional angiography were compared as to their ability to depict several rates of extravasation of contrast material in a model of GI bleeding. DSA tended to be more sensitive for the detection of simulated extravasation (P less than .07).  相似文献   
995.
We investigated in an open, explanatory study a total of 24 patients meeting DSM-III-R criteria for schizophrenia. Eighteen patients were treated for at least 4 weeks with a fixed dose of orally administered haloperidol for at least 4 weeks (mean daily dosage ranging from 0.07 to 0.35 mg/kg b.w.), and 6 patients received haloperidol decanoate with a fixed dose for at least 4 months (dosage range 50–150 mg/4 weeks; calculated mean daily dosage ranging from 0.02 to 0.09 mg/kg b.w.). One week after injection of haloperidol decanoate, the single photon emission computed tomography examination was performed. Our data suggest that D2-dopamine-receptor occupancy of 50 mg/4 weeks haloperidol decanoate 1 week after injection corresponds to an oral dose of 4.5 mg/day haloperidol.  相似文献   
996.
997.
998.
We analyzed the results and the follow-up in our first 80 patients after percutaneous balloon aortic valvuloplasty (BAV) since November 1986. Mean age was 74 +/- 10 years, 78 patients were in the NYHA functional classes III or IV. Initially we used relatively small balloons (15-18 mm), later balloons of 20 mm and, with increasing frequency, of 23 mm diameter were utilized, providing very strong inflations at the end of the procedure. The average valve area after BAV increased from initially 0.75 +/- 0.18 to 0.87 +/- 0.28 cm2 after July 1987. Using the 23-mm balloon a mean valve area of 1.05 +/- 0.19 cm2 was obtained. The procedure-related mortality was 2.5%, the total early mortality (30 days) was 6.25%. Other non-fatal complications included two cases of severe valve incompetence requiring valve replacement, one dissection in the aortic root, one cerebrovascular accident, and eight cases of arterial damage (surgical repair). Twenty-six patients with initially successful dilation were restudied hemodynamically, 12 of whom had a restenosis (46%) after 5 months; 13 patients had a second dilatation. The clinical improvement was remarkable (at least 1 NYHA functional class) in 79% of the patients. 33% were improved 1 year and 20% 18 months after the first or eventually the second BAV. Eighteen of the discharged patients died in the follow-up period (two after valve replacement); 20 patients had aortic valve replacement due to restenosis. Our results show a correlation of the maximal balloon size to the valve area after BAV. However, even a perfect technique cannot prevent the restenosis that occurs mostly during the first year. Therefore, BAV may be useful and appropriate for selected patients with inoperable aortic stenosis, but it is no alternative to valve replacement.  相似文献   
999.
1000.
Newborns suffering from short bowel syndrome (SBS) after massive intestinal resection have numerous infectious complications, which may be due to immunoincompetence from the loss of gut-associated lymphoid tissue (GALT). This study examines the ontogeny of GALT in the rat with SBS. A total of 36 3-week-old rats were divided into two groups: I, sham operated (C, n = 16); and II (SBS, n = 20), with a 50% resection of small intestine with jejunoileostomy. At 4, 5, 6, and 10 weeks of age the animals were sacrificed and the GALT was assessed by video analysis and immunoperoxidase monoclonal antibodies, OX8 (CD8), W-3/25 (CD4), and MARA-2 (IgA). The data were expressed as positive staining lymphocytes per 10(4) microns2 (mean +/- SD). table; see text In the sham group there was an increase in all lymphocyte subsets over time. In the SBS group there was a rapid fall in OX8 and W-3/25 T-lymphocytes by 10 weeks, with no increase in IgA plasma cells at 6 and 10 weeks. This study demonstrates that in the massive bowel resection in the suckling rat decreases the T- and B-lymphocyte populations in the GALT. This lack of development may underlie the associated infectious complications and malabsorption in SBS.  相似文献   
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