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961.
BA Reiling LL Berger DB Faulkner FK McKeith TG Nash FA Ireland 《Canadian Metallurgical Quarterly》1996,74(9):2043-2051
Three studies were designed using a 2 x 2 factorial arrangement of treatments within each experiment to evaluate the effects of various management techniques on growth and carcass traits of once-calved heifers. In Exp. 1, 33 yearling (16 control [C] and 17 prenatally androgenized [PA]) and 39 once-calved (20 C and 19 PA) nonpregnant heifers were used to evaluate the effects of age and PA. Once-calved heifers were approximately 31 kg heavier (P < .03) on-test, initially consumed 11% more (P < .01) DM, and gained 11% faster (P < .08), but had similar (P = .44) gain to feed ratios (.138 vs. .131) as yearlings. Growth performance was not affected by PA. The yearling and once-calved heifers were then slaughtered at approximately 707 and 1,080 d of age, respectively. Despite maturity differences (P < .01), marbling scores (P = .26) and percentage of choice carcasses (P = .27) were similar. However, on the basis of newly accepted grading changes, percentage of once-calved heifer carcasses grading choice decreased from 57.3 to 34.4%. Organoleptic properties did not differ. Experiments 2 and 3 were then conducted to evaluate effects of commercially available products (melengestrol acetate [MGA] and Synovex-H) on feedlot characteristics of heifers following weaning of their first calf. In Exp. 2, 48 once-calved Simmental-based heifers were fed during the summer to a constant compositional fat thickness of .8 cm. Experiment 3 was conducted in the late fall and early winter, during which 52 moderately sized heifers were fed for 116 d postweaning and slaughtered. Performance of heifers in Exp. 2 was not affected by MGA. However, heifers fed MGA in Exp. 3 gained 9% faster (P < .05) than controls. In Exp. 2, Synovex-H tended to improve ADG (P < .09) and feed efficiency (P < .07), but did not affect performance in Exp. 3. Most carcass traits were not affected by either treatment. Nonpregnant, once-calved heifers seem to have a large capacity for efficient weight gain as compared with yearling heifers. However, hormonal compounds, such as testosterone propionate provided pre- or postnatally (Synovex-H), and MGA do not appear to provide the consistent, positive responses often seen with younger, more typical feedlot heifers. 相似文献
962.
Modifying 100,000 lines of 20-year-old code, IBM-FSD successfully applied its software engineering principles to modernization of the FAA'S air traffic control system. 相似文献
963.
Roentgenographic studies in a patient with shoulder instability generally identify the presence of a Hill-Sachs lesion, the presence of bony abnormalities of either the anterior or posterior rim, the presence or absence of fractures, and thick pathologic changes in the joint structure, which not only may provide insight into the diagnosis, but also may give the clinician insight into whether these pathologic changes are likely to be improved with operative and nonoperative treatment modalities. Clearly, the anteroposterior view, particularly with internal rotation, seems important in the diagnosis of the unstable shoulder. The West Point axillary view seems to be a useful one to identify the presence of glenoid rim problems. An additional view, such as the Stryker notch view, may identify the extent and presence of Hill-Sachs lesion when this may not be present on the other two views. Computed tomography arthrography, magnetic resonance imaging scan, and stress testing probably has limited applicability in the routine roentgenographic diagnosis of the unstable shoulder. 相似文献
964.
965.
OBJECTIVE: To determine which elements of clinical history, physical examination, and diagnostic tests are important to primary care physicians in their management of foot ulcers in diabetic patients. RESEARCH DESIGN AND METHODS: We conducted a national mail survey of 600 primary care physicians to determine which patient characteristics and diagnostic test results were important in their decisions to seek radiographic studies, surgical referrals, and hospitalization for diabetic patients with foot ulcers. RESULTS: The case characteristics most likely to influence physicians to order advanced diagnostic or therapeutic interventions are the presence of osteomyelitis on plain radiographs, the failure of the ulcer to improve with conservative therapy, and the presence of visible bone, crepitus, or necrosis within the ulcer (P < 0.001). Information from the initial clinical history was less likely to influence physicians to order advanced diagnostic or therapeutic interventions (P < 0.001) than was information from the physical examination. CONCLUSIONS: We conclude that 1) the patient's history is relatively unimportant to primary care physicians in their management of diabetic foot ulcers; 2) the failure of conservative management is a major reason that primary care physicians order surgical referral, hospitalization, or radiographic testing for diabetic patients with foot ulcers; and 3) primary care physicians rely heavily on plain X ray of the foot, a test with poor sensitivity and specificity, in deciding whether to order further interventions for their diabetic patients with foot ulcers. 相似文献
966.
967.
968.
Anti-glomerular basement membrane (GBM) disease is characterized by the production of an autoantibody with very restricted specificity, with no evidence of polyclonal B cell activation. It was therefore surprising to find that in a solid-phase ELISA a proportion of anti-GBM sera showed significant binding to pyruvate dehydrogenase (PDH), a reactivity usually associated with the antimitochondrial autoantibodies (AMA) found in primary biliary cirrhosis (PBC). The specificity of this reactivity was confirmed by inhibition and competition experiments. The AMA found in anti-GBM sera were of much lower affinity than those found in PBC sera, and recognized a more restricted set of species (mainly the 55-kD and occasionally the 74-kD component of PDH). However, it was possible to block the binding in a Western blot of an anti-GBM serum to both the 55-kD and 74-kD species with F(ab')2 fragments prepared from a PBC serum. Although AMA have been found in diseases other than PBC, such diseases have usually been characterized by polyclonal B cell activation. The stimulus to the production of AMA in anti-GBM disease, and their significance in pathogenesis (if any), are unknown. 相似文献
969.
The association of education with coronary heart disease mortality in the USSR Lipid Research Clinics Study 总被引:1,自引:0,他引:1
BH Dennis GS Zhukovsky DB Shestov CE Davis AD Deev H Kim HA Tyroler 《Canadian Metallurgical Quarterly》1993,22(3):420-427
There is a strong inverse association between educational attainment and coronary heart disease (CHD) mortality in men in the USSR Lipid Research Clinics (LRC) Study. Less educated men were characterized by higher mean blood pressure, high density lipoprotein cholesterol (HDL-C), cigarettes smoked and by lower mean low density lipoprotein cholesterol (LDL-C) and body mass index (BMI). With respect to nutritional variables, less educated men were characterized by higher mean energy per kg body weight and alcohol intake and by lower mean intake of fat, saturated, mono- and polyunsaturated fatty acids, cholesterol, sucrose, and other sugars. The Keys score closely predicted the differences in plasma cholesterol among the educational groups in the randomly selected sample. In men without CHD at entry, the age and clinic-adjusted relative risk for CHD mortality was 2.4 for the least educated compared with the most educated group; on adjusting for systolic blood pressure, HDL-C, LDL-C, BMI, alcohol intake and number of cigarettes, the relative risk was reduced to 1.9. These data indicate that only 22% of the twofold excess of CHD mortality associated with low education was statistically attributable to the major risk factors. The failure to explain more of the education-CHD mortality gradient in the USSR LRC cohort was similar to observations from cohort studies in Great Britain and the US. Other correlates of low education must be explored to explain the association. 相似文献
970.