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101.
102.
As shown in 5507 white participants in a total population sample, the level of fatness is systematically related to lipid levels and to blood pressure levels in older adolescents, younger adults, and older adults of both sexes. At all three age levels, the fatter subjects were highest in serum cholesterol, serum triglycerides, and systolic and diastolic blood pressure and more often hypertensive. The effect of fatness level on the four risk factors was similar for all four skinfolds regardless of location. Fatness level is thus related to lipid levels and blood pressure levels in both younger and older subjects, and there is no evidence that "central" or "peripheral" or upper body and truncal skinfolds are more directly related to these risk factors even after the sixth decade.  相似文献   
103.
Chronic medical illness, and the resulting feelings of alienation, dependency, and distress, represent significant psychiatric issues in the general hospital setting. This article presents the results of the first 3 years of a pilot psychotherapy group at UCLA. This group differed from the typical didactic or support groups offered within the hospital in that membership was not limited to any particular diagnostic group. It was hypothesized that such a multidiagnosis group would facilitate exploration of dynamic and interpersonal issues. Both the group process and the response of the membership supported this hypothesis. However, an interesting distinction emerged within the group between members who saw themselves as chronically medically ill and those who defined themselves as disabled. "Disabled" members were generally less satisfied with the group and tended to benefit less than other members. In light of the above findings, we offer recommendations for establishment of similar groups in other hospital settings.  相似文献   
104.
The validity and reliability of hand-held dynamometry and Cybex dynamometry were investigated using maximal isometric contractions of the external rotators of the shoulder in 14 healthy male subjects. Three maximum voluntary contractions were recorded from each subject by a hand-held dynamometer and a Cybex isokinetic dynamometer at two testing sessions approximately 1 week apart. Analysis of variance did not reveal any significant differences between the mean peak torques obtained with either instrument or between days. The intrarater reliability was clearly established for both the hand-held dynamometer (r = 0.986) and Cybex dynamometer (r = 0.993). Within-day correlations between the two instruments accounted for 27% (day 1) and 60% (day 2) of the explainable variance. This suggests that although both techniques produced identical peak torque values and measured the same element of performance-strength, they did so in a slightly different manner. The possible nature of these differences is discussed.J Orthop Sports Phys Ther 1988;10(6):213-217.  相似文献   
105.
106.
Runners' diarrhea. Different patterns and associated factors.   总被引:6,自引:0,他引:6  
One hundred and nine distance runners participated in a questionnaire survey of bowel function related to running. Thirteen (12%) had had fecal incontinence while running. Sixty-eight (62%) had stopped to have a bowel movement while training. Forty-seven (43%) had "nervous" diarrhea before competition and 13 (12%) had stopped during competition for a bowel movement. Fifty-one (47%) had experienced diarrhea after racing or hard runs and 17 (16%) had seen blood in their stool in the same situations. Runners who had nervous diarrhea before competition were more likely to have symptoms of milk intolerance and irregular bowel function when not exercising, and runners who had symptoms of the irritable bowel syndrome often had to stop for a bowel movement during training. Runners with diarrhea after racing or hard runs frequently experienced severe abdominal cramps, nausea and vomiting, and occasionally, rectal bleeding at the same time. Any form of "runners' diarrhea" was unrelated to age, previous intestinal infection or food poisoning, food allergies, or dietary fiber.  相似文献   
107.
Primary insomnia, major depression, and narcolepsy are usually considered to be separate disorders, distinguished by different polysomnographic profiles. But do polysomnographic data provide adequate evidence to segregate the three disorders, or might they display fundamentally the same sleep disturbance, differing only in degree? To test the viability of these two alternate hypotheses, the authors performed a meta-analysis of controlled polysomnographic studies of these disorders. A summary measure of degree of sleep disturbance was constructed from five variables: wakefulness after sleep onset, percentage of stage 1 sleep, percentage of stage 3 + 4 sleep, rapid eye movement (REM) latency, and REM density. The results of available studies for each variable were combined using a weighted average of effect sizes. An overall "sleep disturbance index" was then calculated by combining the estimates for the five above listed variables. On both the individual measures and especially on the summary index, insomnia, depression, and narcolepsy were arrayed on a simple continuum of progressively more severe sleep disturbance--congruent with the clinical observation that these disorders display progressively more disturbed sleep. These findings suggest that sleep can be disturbed in only a limited number of ways: in evaluating sleep architecture, it may not be possible to elaborate much beyond a single axis of good-to-bad sleep. Thus, polysomnographic measures may not provide adequate evidence to classify insomnia, depression, and narcolepsy as separate entities.  相似文献   
108.
Back support mechanisms during manual lifting   总被引:1,自引:0,他引:1  
The ability of individuals to lift heavy loads without injury to the vertebral elements has led to the formulation of several explanations of this phenomenon. In this article, the existing literature on lifting is reviewed and mechanisms of back support during lifting are described. These mechanisms include the intra-abdominal pressure mechanism, the thoracolumbar fascia mechanism, and combinations of these mechanisms with the use of the erector spinae, multifidus, and psoas muscles. Physical therapists are often responsible for teaching patients and workers "proper" lifting techniques; however, controversy exists concerning the proper lift. Although lifting with the lower back in flexion and lifting in extension have been proposed, there are indications for each depending on individual circumstances. Lifting instructions for workers without low back injuries should be distinguished from instructions for patients with low back pain. General rules for lifting include: plan the lift, avoid twisting, keep the load close to the body, and bend at the knees.  相似文献   
109.
Morphology and function of lacrimal gland acinar cells in primary culture   总被引:6,自引:0,他引:6  
The objectives of the current investigation were fourfold: (1) to establish an effective procedure for the isolation of acinar cells from the rat lacrimal gland; (2) to evaluate the functional capacity of freshly isolated cells; (3) to determine defined culture conditions which permit maintenance of viable, differentiated cells, as well as secretory component (SC) production, during long-term culture; and (4) to characterize the morphological features of cultured cells. Acinar cells were isolated by serial incubation of gland fragments in chelating and enzymatic solutions, followed by centrifugation through a Ficoll gradient. The yield of viable cells/gland appeared to be age-dependent: cell recovery was inversely proportional to the age of the animals. Immunofluorescence analysis of freshly isolated cells showed the presence of SC, the IgA antibody receptor, within isolated cells. In addition, experiments with a labeled analog (Nle4-D-Phe7-alpha MSH) of alpha-melanocyte-stimulating hormone (alpha-MSH) demonstrated specific binding sites on freshly isolated cells; alpha-MSH is a known modulator of acinar protein secretion. Maximum binding of the alpha-MSH analog occurred within 30 min, was dependent upon cell density and was reduced by coincubation with unlabeled alpha-MSH. To determine the culture requirements of acinar cells, cells were cultured on a variety of substrates (plastic or modified plastic [Primaria], coated with or without extracellular matrix [Matrigel]) in the presence or absence of various supplements and/or fetal calf serum (FCS) for 0.7 to 3.5 weeks. Cell attachment, function and long-term viability required an extracellular matrix. Moreover, in long term cultures (25 days), acinar cell attachment was enhanced by the inclusion of supplements to media containing 10% FCS. Replacement of serum with fibroblast growth factor, high-density lipoprotein and an increased concentration of epidermal growth factor resulted in a distinct "cobblestone" morphology characteristic of epithelial cell cultures. Electron microscopic analysis of cells cultured in supplemented serum-free media demonstrated extensive rough endoplasmic reticulum and Golgi, intermediate filaments and numerous secretory granules, as well as tight junctions and desmosomes. In addition to cell maintenance and attachment, acinar cell synthesis and/or secretion of SC was positively influenced by inclusion of supplements in the media. In summary, we have isolated lacrimal gland acinar cells, which express receptors for IgA antibodies and alpha-MSH. In addition, we have defined culture conditions which permit the long-term maintenance of SC-secreting acinar cells.  相似文献   
110.
Leishmania donovani is an important intracellular protozoal pathogen of humans, which resides solely within mononuclear phagocytes. Phase-contrast microscopy and cinemicroscopy were used to examine the interaction of L. donovani promastigotes with human phagocytes to characterize and quantitate the sequence of events that results in leishmanial infection.  相似文献   
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