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41.
Effect of atropine and vagotomy on response of transplanted pancreas.   总被引:3,自引:0,他引:3  
It is well established that atropine and vagotomy inhibit pancreatic enzyme secretion in response to intestinal stimulants such as fat or amino acids. These effects are usually attributed to interference with hypothetical vagal cholinergic mechanisms that facilitate release of cholecystokinin. To determine whether atropine or vagotomy interferes with release of humoral stimulants of pancreatic enzyme secretion, we studied their effect on protein secretion from an autotransplanted portion of pancreas in response to intestinal stimulants in dogs. The transplanted pancreas was as sensitive as the intact pancreas to stimulation by exogenous caerulein, a cholecystokinin-like peptide, and this response was not altered by atropine or vagotomy. Therefore, if vagotomy or atropine interferes with release of humoral pancreatic stimulants, they would be expected to reduce the response of the transplanted pancreas just as they do of the intact pancreas. Truncal vagotomy caused no significant change in protein secretion from the transplant in response to intestinal perfusion with sodium oleate or tryptophan. Atropine was tested only against sodium oleate and caused no change in response. We conclude that release of humoral pancreatic excitants of protein secretion in response to intestinal stimulants is not significantly changed by atropine or vagotomy.  相似文献   
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Using two restriction site polymorphisms within the structural gene coding for human type II collagen we have examined the segregation of this gene in three pedigrees with dominantly inherited osteogenesis imperfecta (Sillence type IA). We have demonstrated that the gene does not segregate with clinical expression of the disease and cannot, therefore, contain the mutation responsible for osteogenesis imperfecta in these families.  相似文献   
44.
Adhesion formation is a major source of postoperative morbidity and mortality. In this study, the ability of a variety of lazaroid formulations [the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p. adhesion formation in three rabbit models was examined. In initial studies, PNU83836E was administered via Alzet miniosmotic pump to the site of injury. In the sidewall and double uterine horn models, PNU83,836E was administered via Alzet miniosmotic pump for the entire postoperative interval. In the sidewall model, there was a dose- dependent reduction in the area of the sidewall injury that was involved in adhesions. In the double uterine horn model, PNU83,836E was administered via Alzet miniosmotic pump to the area of injury for 1, 2, 3 or 7 days. Administration for as little as 24 h after surgery significantly reduced the extent of adhesion formation and the reduction was increased if it was administered for longer. Further studies were conducted in which various lazaroid formulations were administered as a bolus at the end of surgery. In both the sidewall and double uterine horn models, administration of either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or lipid emulsion vehicles) at the end of surgery reduced adhesion formation. Administration of a bolus of PNU74006F 10 min prior to initiation of surgery with or without additional treatment at the end of surgery further increased its efficacy in the reduction of adhesion formation. Administration of a minimum of 1.5 mg before and after surgery (3 mg total) was required for maximal efficacy. These studies demonstrate that pre- and postoperative administration of either a steroidal (PNU74006F) or non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation and reformation of postoperative adhesions in three animal models.   相似文献   
45.
Most issues of the instinct controversy were defined in the seventeenth century. Eighteenth-century French enlightenment was vigorous in rejecting the instinct concept but Reimarus demonstrated its validity. The advance of natural theology, and later of Darwinism, led to wide acceptance of instinct in the nineteenth century, but the twentieth witnessed a revival of anti-instinct attitudes on the eighteenth-century model. Extraneous influences still impede recognition of scientific evidence for the importance of innately determined behavior.Division 26, American Psychological Association, Montreal, Canada, August 1973 (revised).  相似文献   
46.
At the University of California, Irvine Medical Center, an end-of-life curriculum was implemented in 2000 for an internal medicine residency utilizing a longitudinal approach that allowed residents to follow patients through their entire hospice experience. An elective home hospice rotation was developed for which third-year residents served as primary care physicians for patients at the end of life over a one-year period. Residents were supervised by faculty who were hospice medical directors. They also learned through case vignettes, quarterly meetings, textbook reading, and personal projects. From July 2000 to June 2002, residents demonstrated positive attitudes towards hospice care and recommended the rotation highly (mean 8.86 on a scale of 1-10). The rotation grew in popularity from six initial residents to ten residents the next year, and has since become a mandatory rotation for all senior residents. A 360-degree evaluation uniformly indicated positive resident performance from the hospice team (mean scores 7.56-8.69 on a 1-9 scale), family (mean scores 9.3-9.7 on a 1-10 scale) and faculty (mean scores 7.29-7.72 on a 1-9 scale). Residents were also pleased with the level of teaching (mean 8.86 on a scale of 1-10) and felt that the patient care load was "just right." Their knowledge improved by 8% (p =.0175). In conclusion, a longitudinal hospice rotation was implemented that fulfilled curricular goals without undue burden on the residents or residency program.  相似文献   
47.
Objective: Previous work has shown that manic-depressive illness and alcohol abuse are linked. This study further explores the relationship of alcohol and drug abuse in bipolar I patients and unipolar depressives and a comparison group obtained through the acquaintance method. Method: Diagnosis was accomplished according to Research Diagnostic Criteria (RDC): controls=469; bipolars=277; unipolar depressives=678. Systematic data were gathered using the SADS on lifetime and current drug abuse and alcoholism. Both patients and comparison subjects were then followed prospectively for 10 years. First degree family members were interviewed using the RDC family history method. Results: The group of bipolar patients and the group of unipolar patients had higher rates of drug and alcohol abuse than the comparison group when primary and secondary affective disorder patients were combined. However, primary unipolar patients did not have higher rates of alcohol or drug abuse than the comparison group. In contrast, primary bipolar patients had higher rates of alcoholism, stimulant abuse, and ever having abused a drug than the primary unipolar group and the control group. In an evaluation of the bipolar patients, drug abusers were significantly younger at intake and had a significantly younger age of onset of bipolar disorder. There was a significant increase in family history of mania or schizoaffective mania in the drug-abusing bipolar patients as compared to the non-abusing bipolar patients. Limitation: As in all adult samples of patients with affective illness, the chronology of alcohol and substance problems vis-à-vis the onset of illness was determined retrospectively. Conclusions: (1) Alcoholism and drug abuse are more frequent in bipolar than unipolar patients. (2) The drug abuse of bipolar patients tends toward the abuse of stimulant drugs. (3) In a bipolar patient, familial diathesis for mania is significantly associated with the abuse of alcohol and drugs. (4) More provocatively, these findings suggest the hypothesis of a common familial-genetic diathesis for a subtype of bipolar I, alcohol and stimulant abuse. Clinical implications: The present analyses, coupled with two previous ones from the CDS, suggest that drug abuse may precipitate an earlier onset of bipolar I disorder in those who already have a familial predisposition for mania. Furthermore, in dually diagnosed patients with manic-depressive and alcohol/stimulant abuse history, mood stabilization of the bipolar disorder represents a rational approach to control concurrent alcohol and drug problems, and should be studied in systematic controlled trials.  相似文献   
48.
Two enzyme-linked immunosorbent assays were established and compared for the estimation of plasma aldosterone. In the first method immobilized aldosterone-protein complexes on the ELISA plates compete with aldosterone to be determined for the binding of certain amount of anti-aldosterone antibodies. The sensitivity of this method depends on the protein carrier used to conjugate with aldosterone. In the second method, anti-aldosterone antibodies adsorbed on ELISA plates compete for binding of known amount of the enzyme-labeled aldosterone and aldosterone to be determined. The highly specific rabbit anti-aldosterone antibodies were obtained by injection of aldosterone-oxime thyroglobulin. The detection limit of aldosterone in both methods ranged between 2-20 pg. The proposed assays are suitable for the determination of aldosterone in biological fluids compared with other reported ELISA assays, as well as with RIA.  相似文献   
49.
Only a few studies of long-term survivors of AIDS (those who survive more than twice the median expected time) have been done but these reveal a constellation of psychological characteristics including, but not limited to, those with active coping, social support, life involvement, ability to communicate, and active collaboration with one's doctor. Another related literature consists of longitudinal studies following people infected with the HIV virus to determine whether psychological characteristics are related to disease progression. These studies have focused on coping, depression, negative expectancies and social support as predictors. This article reviews and integrates the two bodies of literature combining the variables identified into four psychosocial strategies related to longer survival with HIV/AIDS: following healthy self care; maintaining connectedness; having a sense of meaning or purpose in life; and maintaining perspective. Affect, beliefs, and behaviour are all seen as important. Biological variables, SES and psychological resources that the person brings to the situation and external stresses are seen as important variables to consider in prediction studies. The pathways through which these four strategies may operate (both psychological and biological) to impact on health are discussed. Psychological pathways include distress and behavioural disengagement, while biological pathways involve the sympathetic nervous system, neuroendocrine and immune mediation. Finally suggestions for future research are given.  相似文献   
50.
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