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131.
132.
Falls among the elderly: epidemiology and prevention   总被引:1,自引:0,他引:1  
Harmful psychological and physical consequences may result when elderly people fall. I summarize the epidemiology of falls among elderly people and focus on three potentially remediable causes of falls: reduced peripheral neurosensation, the use of psychoactive medication, and environmental hazards. From 1960 to 1980, death rates from falls among white persons 75 years of age and older have decreased by more than 50%. Fall rates among community-dwelling elderly people increase with age and are greater for women than men. The death rates from falls, however, are now greater for men than women. Reduced peripheral neurosensation in the lower extremities may be a significant cause of falls among the elderly. Recreational walking or physical therapy may improve these deficits and lead to fewer falls. The use of psychoactive medications, most commonly benzodiazepine sedatives, is possibly associated with an increased risk of falls and hip fractures; greater caution in the use of these medications is warranted. The elimination or redesign of steps and curbs and the provision of hand railings and walking aids may be the most effective environmental approaches to preventing falls. These conclusions need further study in community-dwelling elderly populations.  相似文献   
133.
The relationship between stroke and physical disability was examined in a cohort of adult, Framingham, Massachusetts, residents who, between 1948 and 1951, were assembled for a longitudinal examination of cardiovascular disease. Multivariate analyses examined the amount of residual disability attributable to stroke among 2540 community-dwelling survivors, 27 years after their initial examination, after controlling for age, cardiovascular risk factors, other cardiovascular diseases, and eight general health conditions related to physical disability. Among men living in the community, a history of stroke explained 12% of the variance in physical disability. Suffering a stroke, however, was not as strongly related to physical disability among women living in the community, accounting for only 3% of the variance. Results suggest that although older men and women die from the same major causes, they may not be disabled by the same conditions.  相似文献   
134.
Mice killed shortly after receiving c. 2000 spores of a type E strain of Clostridium botulinum per os were incubated at one of five chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10%, w/v) and pure cultures were then titrated for toxicity. Some of the main findings were confirmed with two further type E strains. Toxicity produced at 37 degrees C was poor in both carcasses and cultures (200-20,000 mouse intraperitoneal LD/g or ml). It was good in both systems at 30 and 23 degrees C, usually reaching 20,000-200,000 LD/g or ml, and in carcasses occasionally more; at 30 degrees C maximal toxicity was reached more quickly in carcasses than in cultures. Prolonged incubation (36-118 days) at 30 or 23 degrees C resulted in complete loss of toxicity in virtually all carcasses but not in cultures. At 16 degrees C the development of toxicity in carcasses was strikingly greater than in cultures. At 9 degrees C neither system produced more than slight toxicity after prolonged incubation. Trypsinization increased the toxicity of cultures but not usually of carcasses. Unfiltered carcass homogenate (10%, w/v) with maximal intraperitoneal toxicity was harmless for mice by mouth in doses of 0.25 ml. These findings differed in important respects from those made earlier with a type C strain.  相似文献   
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Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa.  相似文献   
138.
The present study evaluated99mTc(V) DMSA as an agent for the visualization of inflammatory lesions in comparison to99mTc(HI) DMSA and99mTc-HIG. All three radiopharmaceuticals were prepared with commercial kits.99mTc(V) DMSA was prepared at neutral pH by the addition of first bicarbonate and then pertechnetate to the kit contents. The labeling efficiency was 99% as determined by ITLC. Abscesses were induced by i.m. injection of 50 μl turpentine into the right thighs of 36 Swiss albino mice. Six days later 3.7 MBq of each radiopharmaceutical was i.v. administered to 12 mice. The mice were sacrificed at 1,3,6 and 24 h later. Scintigrams were obtained with a gamma camera. The abscesses were better visualized on scintigrams with99mTc(V) DMSA compared to99mTc(III) DMSA, starting at 1 h. The animals were dissected and the organs were removed, weighed and the radioactivity determined with a gamma counter. The abscess to other tissue ratios were higher with99mTc(V) DMSA than the other radiopharmaceuticals. The max. abscess/muscle ratios were 9.46 ± 3.20 (24 h), 4.19 ± 1.39 (6 h) and 5.98 ± 1.17 (24 h) and max. abscess/blood ratios were 6.22 ± 1.41, 4.09 ± 0.84 and 0.914 ± 0.351 all at 24 h for99mTc(V) DMSA,99mTc(III) DMSA and99mTc-HIG, respectively. Experimental arthritis was produced in 6 New Zealand white rabbits by intra-articular injection of ovalbumin. Four days later 37 MBq of99mTc(V) DMSA and99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h clearly demonstrated arthritic joints. ROFs over arthritic joints were compared to contralateral normal joints (A/C). The max. A/C ratios were 2.10 ± 0.31 (3 h) and 2.92 ± 0.99 (24 h) for99mTc(V) DMSA and99mTc-HIG, respectively. Our results indicated the feasibility of imaging inflammatory lesions with99mTc(V) DMSA.  相似文献   
139.
Spinal epidural hematoma. Report of a case and review of the literature   总被引:3,自引:0,他引:3  
We report the case of a thoracic epidural hematoma at the T7-T9 level which occurred after placement of spinal epidural catheter for continuous anaesthesia in acute pancreatitis. The male patient felt a sudden back pain after six days of successful analgesia and became paraplegic 24 hours afterwards. An emergency laminectomy and removal of the hematoma were performed; however, the patient recovered only incompletely.We discuss the clinical signs and symptoms of spinal epidural hematoma as well as its diagnostics and therapy. The controversial views from the literature concernings its etiology are critically reviewed.  相似文献   
140.
Transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES) of the human motor cortex produce a silent period (SP) following motor evoked potentials (MEPs). The early part of the SP can be explained by decreased alpha motor neuron excitability, whereas the late part is presumably due to suprasegmental mechanisms. In order to determine the level of the suprasegmental contribution to the generation of SPs, we recorded excitatory and inhibitory responses to TMS, TES, and percutaneous electrical brainstem stimulation (PBS) in the voluntarily activated first dorsal interosseous muscle of the hand. Stimulus intensities were set so that PBS and TES induced MEPs with areas equal to or larger than those of MEPs obtained with TMS. This procedure revealed that SPs were 49% and 83% shorter with TES and PBS, respectively, than with TMS. As TMS is more effective than TES or PBS in activating cortical interneurons, these findings support the idea that a significant component of the SP arises from intracortical mechanisms.  相似文献   
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