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931.
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Although angiography and carotid artery surgery are illadvised in patients with acute, profound stroke, there is no consensus on the management of patients with stroke in evolution, waxing and waning neurologic deficits, or crescendo transient ischemic attacks. This type of clinical picture was associated with a critical, unstable lesion of the internal carotid artery in each of 12 patients. Emergency angiography permitted identification of the lesions responsible for the varying neurologic manifestations, and emergency carotid thromboendarterectomy produced prompt, complete recovery in all but one patient, who had a total carotid occlusion, received no operation, and died of a cerebral infarction. Based on our experience with these 12 patients, an aggressive diagnostic and therapeutic approach is recommended for patients with acute unstable cerebrovascular disease. 相似文献
933.
WS Linn JD Hackney EE Pedersen P Breisacher JV Patterson CA Mulry JF Coyle 《Canadian Metallurgical Quarterly》1976,114(3):477-483
Similar populations of male and female office workers in San Francisco, which has little air pollution, and in Los Angeles, which experiences frequent photochemical smog episodes, were surveyed in an attempt to document excess respiratory symptoms and dysfunction in Los Angeles relatable to air pollution. Most results of forced expiratory tests, single-breath N2 tests, and questionnaire interviews did not differ significantly between cities. Los Angeles women reported nonpersistent cough and phlegm more often than did San Francisco women. Smokers in both cities showed increased functional abnormalities. These results suggested that Los Angeles oxidant exposure is far less significant than smoking as a risk factor in development of chronic respiratory disease in sedentary indoor workers in good general health. Oxidant exposure has not been ruled out as a significant risk to more heavily exposed on more highly susceptible persons. 相似文献
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938.
DC Bauer WS Browner JA Cauley ES Orwoll JC Scott DM Black JL Tao SR Cummings 《Canadian Metallurgical Quarterly》1993,118(9):657-665
OBJECTIVE: To determine the factors associated with appendicular bone mass in older women. DESIGN: Cross-sectional analysis of baseline data collected for a multicenter, prospective study of osteoporotic fractures. SETTING: Four clinical centers in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela valley, Pennsylvania. PATIENTS: A total of 9704 ambulatory, nonblack women, ages 65 years or older, recruited from population-based listings. MEASUREMENTS: Demographic and historical information and anthropometric measurements were obtained from a baseline questionnaire, interview, and examination. Single-photon absorptiometry scans were obtained at three sites: the distal radius, midradius, and calcaneus. Multivariate associations with bone mass were first examined in a randomly selected half of the cohort (training group) and were then tested on the other half of the cohort (validation group). RESULTS: In order of decreasing strength of association, estrogen use, non-insulin-dependent diabetes, thiazide use, increased weight, greater muscle strength, later age at menopause, and greater height were independently associated with higher bone mass. Gastric surgery, age, history of maternal fracture, smoking, and caffeine intake were associated with lower bone mass (all P < 0.05). For example, we found that 2 or more years of estrogen use was associated with a 7.2% increase in distal radius bone mass, whereas gastrectomy was associated with an 8.2% decrease in bone mass. The associations between bone mass and dietary calcium intake and rheumatoid arthritis were inconsistent. Alcohol use, physical activity, use of calcium supplements, pregnancy, breast-feeding, parental nationality, and hair color were among the many variables not associated with bone mass. Multivariate models accounted for 20% to 35% of the total variance of bone mass. CONCLUSIONS: A large number of factors influence the bone mass of elderly women; however, age, weight, muscle strength, and estrogen use are the most important factors. 相似文献
939.
WS Shestowky CF Holmes T Hu J Marr JL Wright J Chin HM Sikorska 《Canadian Metallurgical Quarterly》1993,192(1):302-310
Okadaic acid (OA), produced by marine phytoplankton, is the parent compound of a family of marine toxins responsible for diarrheic shellfish poisoning (DSP). A monoclonal antibody to OA (6/50) (Ab1) has been raised and in turn used for immunization of syngeneic animals. Mice inoculated with the 6/50 idiotype produced both anti-idiotypic antibodies (Ab2) and OA binding antibodies (Ab3). The selected anti-idiotypic antibody 1/59 bound to the immunizing 6/50 idiotype but not to F(ab')2 fragments of pooled normal mouse Ig. It inhibited the binding of OA to solid-phase attached F(ab')2 of 6/50 IgG as well as the binding of 6/50 IgG to a solid-phase bound OA. Like OA, 1/59 anti-idiotypic antibody inhibited protein phosphatase 1 and 2A catalytic subunits in a 32P-phosphorylase a phosphatase radioassay. Thus, 1/59 IgG is a novel internal image anti-idiotypic antibody (Ab2 beta) and can serve as a surrogate of OA in biological assays. 相似文献
940.