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991.

Objectives

A natural decline of muscle strength occurs during the aging process; however, preserving muscle strength may lower the rate of many preventable diseases such as diabetes, especially in higher risk populations. The purpose of this study was to examine the sex-specific association between muscle weakness and incident diabetes in older Mexican Americans.

Design

Observational, longitudinal study.

Setting

Urban and rural households in the Southwestern United States.

Participants

A subsample of 1903 Mexican Americans aged at least 65 years without diabetes at baseline were followed for 19 years.

Measurements

Muscle weakness was assessed with a hand-held dynamometer and was normalized to body weight (normalized grip strength). Male and female participants were categorized as weak if their normalized grip strength was ≤0.46 and ≤0.30, respectively. Sex-stratified Cox proportional hazard regression models were used to determine the association between muscle weakness and incident diabetes (self-reported) when using age as an entry variable and after adjusting for education, employment status, instrumental activities of daily living disability, interview language, marital status, and obesity. A sensitivity analysis was performed to account for influential outliers for the outcome variable (incident diabetes) and the model was re-run.

Results

The hazard ratio for incident diabetes was 1.05 (95% confidence interval: 1.02–1.09; P < .001) in weak vs not-weak male participants and 1.38 (95% confidence interval: 1.35–1.41; P < .001) in weak vs not-weak female participants, after adjusting for relevant covariates.

Conclusions

Muscle weakness was associated with an increased rate of diabetes in older male and female Mexican Americans. Health professionals should encourage activities that preserve muscle strength, thereby preventing the incidence of diabetes in older Mexican Americans.  相似文献   
992.
993.
Traumatic brain stem injury: MR imaging   总被引:9,自引:0,他引:9  
Gentry  LR; Godersky  JC; Thompson  BH 《Radiology》1989,171(1):177-187
Eighty-seven patients with acute (n = 70) or chronic (n = 17) head injuries were prospectively studied with magnetic resonance (MR) imaging and computed tomography (CT) to characterize the frequency and nature of traumatic brain stem injury (BSI). Forty-eight traumatic lesions were identified in 36 patients. Of 36 patients, 35 had neurologic findings that corroborated the radiographic impression of BSI. T1- and T2-weighted MR images demonstrated a significantly higher number of lesions than did CT. Patients with BSI had a significantly higher frequency of corpus callosum and diffuse axonal "shear" lesions. The number of cortical contusions and extraaxial hematomas was similar in both groups. The mean Glasgow Coma Scale (GCS) scores at admission were significantly lower in patients with evidence of BSI on MR images. Patients with primary BSI had lower initial GCS scores, a longer duration of coma, more diffuse axonal "shear" lesions, and a higher frequency of corpus callosum injury than patients with secondary BSI. The location of primary and secondary lesions was significantly different. Overall, MR imaging was more helpful than CT in detecting, localizing, and characterizing BSI.  相似文献   
994.
995.
In the pithed rat, amidephrine a "selective" alpha 1-adrenoceptor agonist, evokes a positive chronotropic response. This response can be antagonized by prazosin but not by propranolol or by rauwolscine. Similarly, part of the chronotropic response to cardioaccelerator nerve stimulation is resistant to blockade by propranolol but is sensitive to prazosin or WB4101. We conclude that alpha 1-adrenoceptors can mediate a chronotropic response in the rat heart either to exogenous agonists or to the endogenous neurotransmitter noradrenaline.  相似文献   
996.
997.
Irish Journal of Medical Science (1926-1967) -  相似文献   
998.
From January 1986 to January 1987, 116 Mitroflow pericardial valves were implanted in 98 patients at our center. Ages ranged from 10 to 83 years (mean, 64.9 years). Forty-three patients (44%) were in New York Heart Association Functional Class III or IV at the time of surgery. Twelve patients (12%) had undergone prior cardiac surgery. Ten hospital deaths (10%) (70% Confidence Limits, 7% to 14%) occurred. Incremental risk factors for hospital death included female gender (p = 0.08), higher functional class preoperatively (p = 0.04), and longer cardiopulmonary bypass time (p = 0.05). All 88 hospital survivors (100%) were followed for 6 to 13 months (mean, 9 months) after repair. Two late deaths (2.3%) occurred: 1 at 1.5 months from subacute cardiac failure, and another at 5 months from non-valve-related sepsis. Actuarial survival at 15 months was 87% +/- 5.5%. No late reoperations were performed. One patient who exhibited mild mitral incompetence 4 months postoperatively is being followed closely. Two patients (2.3%) who were not on anticoagulant therapy developed thromboembolic events in association with chronic atrial fibrillation. No patient has had hemolysis or infective endocarditis. All patients are now in Functional Class I or II. Our early-phase assessment of this valve reveals a low risk of valve-related events. Its low-profile frame and wide, flexible sewing ring make this prosthesis technically satisfactory for implantation. Continuing close follow-up will determine intermediate-and late-phase hazards.  相似文献   
999.
1000.
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