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101.
When conservative management of intestinal obstruction fails, the surgeon has two operative choices for decompression: the open procedure with enterotomies and suction and the closed procedure consisting of retrograde stripping and nasogastric suction. A previously undocumented complication of the latter procedure — pulmonary aspiration — is reported in a 20-year-old man with small-bowel obstruction. Practical modifications to the technique of small-bowel decompression are suggested. They include feeding the nasogastric tube into the distal duodenum, using a wider bore tube, inserting an esophageal balloon before extubation, using a nasogastric tube with suction throughout extubation and, immediately postoperatively, making a more conscious effort to remove all gastric contents before extubation, and milking the contents distally through the ileocecal valve.  相似文献   
102.
An audit was undertaken to determine how well a primary care team supported lay carers of the demented elderly. The following standards were set: (1) primary care teams should know of the existence of symptomatic demented elderly patients in the community; (2) lay carers should be knowledgeable about dementia; and (3) the resources which the lay carers felt they needed should be supplied unless they were unavailable.

The primary care team knew of the existence of all symptomatic demented elderly patients in the practice but lay carers lacked knowledge about dementia and had unmet needs. Giving lay carers a booklet about dementia and reporting their unmet needs to the primary care team led to improvements in standards 2 and 3. In addition, stress among lay carers was reduced. In spite of a reduction in the number of carers' unmet needs, there was no overall change in the use of available resources following intervention.

It is concluded that structured support is necessary and worthwhile in order to provide effective support for lay carers of the demented elderly in the practice.

  相似文献   
103.
Despite evidence of an interaction between cannabinoids and estrogen in the brain, little information is available regarding the consequences of this interaction on behavior. A within-subjects design was used to examine the effects of estrogen and delta9-tetrahydrocannabinol (delta9-THC) on learning and memory in ovariectomized rats responding under a multiple schedule of repeated acquisition and performance. Treatment with low physiological levels of estrogen, delivered in Silastic capsules, improved response accuracy without affecting response rate during acquisition. Estrogen also attenuated the ability of delta9-THC (0.56- 3.2 mg/kg) to decrease response accuracy and rate during acquisition and response accuracy during performance. Results indicate that estrogen can improve accuracy during acquisition of a nonspatial operant task and can attenuate delta9-THC- induced behavioral deficits.  相似文献   
104.
The cellular response within lesions and in draining lymph was examined in sheep following a primary intracutaneous injection of live or killedS. aureus. Microscopic examination of sections from liveS. aureus lesions (12, 24, 48, and 96 h following vaccination) revealed a high ratio of neutrophils to macrophages at all times. This ratio was initially high following inoculation of killedS. aureus but decreased steadily at successive sampling times. Representative sections from lesions were subjected to indirect immunofluorescent staining to identify IgM-, IgG1-, and IgG2-containing cells. The ratio of IgG2- to IgG1-containing cells in lesions produced following liveS. aureus vaccination was significantly greater than the ratio in lesions produced by killed staphylococci. Lesions induced by liveS. aureus recruited significantly greater numbers of51Cr-labeled allogeneic neutrophils from blood than did lesions induced by killedS. aureus. During the first 6 h this difference was approx. 20-fold. The volume of lymph and the number of leukocytes draining liveS. aureus lesions was considerably greater than from lesions produced by killed staphylococci. The proportion of neutrophils in lymph draining both types of lesions increased markedly during the first two days of the response but was observed to be greater and remained higher for a longer period of time in lymph draining vaccine lesions produced following injection of live staphylococci. The increase in proportion of neutrophils in lymph was accompanied by a concomitant decrease in proportion of lymphocytes and macrophages. No immunoglobulin-containing cells or anti-staphylococcal antibody production was detected in lymph draining either type of lesion. These differences in inflammatory responses may contribute to the documented differences in immune responses to live and killed staphylococcal vaccines.  相似文献   
105.
This paper describes how an age-sex register may be used as a sampling frame for the selection of matched controls in studies of the use of general practice. It discusses both the analysis of data collected in this way and the advantages and limitations of the method itself. The application of the method to a case-study suggests that patients who use hospital accident departments are also high users of general practice. Although care is needed in the interpretation of such results, it is concluded that matched controls can be used to ameliorate some of the problems of research in general practice.  相似文献   
106.
We present two cases of a thrombus in the ascending aorta causing an acute myocardial infarction (AMI) and review the 10 other cases previously reported in the literature. This life-threatening condition appears to be more common in female smokers in their fifth decade. Suspicion should be raised in individuals at low risk for atherosclerotic disease with coronary angiographic findings not in keeping with the clinical presentation. The diagnosis may be obtained by transesophageal echocardiography, and we generally recommend surgical thrombectomy.  相似文献   
107.
Two series of block copolymers have been synthesized comprising of soft polytrifluoroacetaldehyde (polyacetal) segments and of hard 4,4′-methylenedi(phenyl isocyanate)/cis-cyclohexane-1,4-diol polyurethane segments. The series-A copolymers in which the soft segments were directly bound to the hard segments had significantly lower thermal stability than the series-B copolymers in which the soft segments were linked to the hard segments by sebacic ester units. In both series the thermal stability decreased with increasing soft segment content. The series-A copolymers exhibited two thermal transitions both characteristic of Tg's and separated by about 60 K. In contrast the series-B copolymers exhibited two characteristic Tg's separated by 200–250 K, depending on composition, together with an additional endothermic transition at about ambient temperature. All transitions for both series decreased with increasing soft segment content. The observations have been compared with those of other polyether and polyester based polyurethanes.  相似文献   
108.
Because of the importance of the renin-angiotensin system in renal homeostatic mechanisms, the effect of angiotensin administration upon disseminated intravascular coagulation has been studied in rabbits. An infusion of angiotensin II (0.1 μg/kg/min for 2 hours) produced neither histologic abnormalities in the kidneys nor an elevation of creatinine. After an infusion of thrombin (2.0 units/kg/min for 2 hours) only 3 of 10 rabbits, when sacrified 24 hours later, showed histologic lesions comprised of occasional fibrin thrombi and foci of tubular necrosis. Creatinine levels did not rise. In contrast, the combination of angiotensin and thrombin resulted in renal lesions in 12 of 14 animals. Four had frank cortical necrosis, while combinations of tubular necrosis, glomerular thrombosis and segmental glomerular infarction occurred in the others, together with elevated creatinine levels. Blockade of α-adrenoreceptors with phenoxybenzamine in 12 animals did not prevent either these histologic changes or creatinine elevation, showing that the effect of angiotensin was independent of α-adrenoreceptor stimulation. The synergistic interaction between angiotensin and disseminated intravascular coagulation was not explained by differences in the consumption of plasma fibrinogen but apparently was due to localization of fibrin thrombi within glomerular capillaries by the vasomotor actions of angiotensin, as has previously been shown to occur with α-adrenoreceptor simulation. Such a mechanism might contribute to renal glomerular deposition of fibrin in acute ischemic renal failure.  相似文献   
109.
110.
BACKGROUND: Lead remains in high levels in the environment and is known to reduce fertility in animal models, but a direct link between lead exposures and human infertility has not yet been established. METHODS: In a prospective, double-blind study of the metal ion levels and sperm function, semen was obtained from partners of 140 consecutive women undergoing their first IVF cycle. Lead in seminal plasma was determined by atomic absorption spectroscopy. Motile sperm populations were assessed for surface receptors for mannose binding, and the ability to undergo premature ('spontaneous'), and free mannose-induced acrosome reactions. Fertile donor (n = 9) sperm were exposed to exogenous lead during capacitating incubations and then assessed for mannose receptor expression and acrosome loss. RESULTS: Lead levels were negatively correlated with IVF rates. Lead levels were negatively correlated to two of the three sperm function biomarkers (mannose receptors, mannose-induced acrosome reactions). Lead levels positively correlated with the spontaneous acrosome reaction. These findings were mimicked by in-vitro exposure of fertile donor sperm to lead. CONCLUSIONS: Multiple sperm parameters are affected as lead levels rise. Increased lead levels may contribute to the production of unexplained male infertility.  相似文献   
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