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991.
The autonomic innervation of the seminal vesicle from 8 and 16 week streptozotocin-induced diabetic rats and age-matched controls was studied by pharmacological, histochemical and immunohistochemical methods. Contractions in response to electrical field stimulation, which were abolished using prazosin (2 microM) or tetrodotoxin (one to 1.6 microM), and to noradrenaline were significantly increased in both eight and 16 week diabetic animals. The contractile response to acetylcholine was significantly increased in the 16 week diabetic rats only, when compared with controls. Although these responses were significantly increased, no difference was found in ED50 and EF50 values between control and diabetic rats. Vasoactive intestinal polypeptide (0.3 microM) had no effect on resting tension or nerve-mediated responses. In seminal vesicles from control animals, both vasoactive intestinal polypeptide-immunoreactive and acetylcholinesterase-containing nerves were localised around the folds of the columnar epithelium of secretory cells, in contrast to neuropeptide Y-immunoreactive and catecholamine-containing nerves which were found in the smooth muscle layers. In seminal vesicles from both eight and 16 week diabetic animals no difference was seen in distribution or density of acetylcholinesterase-containing nerves; there was an increase in density and fluorescence intensity of vasoactive intestinal polypeptide- and neuropeptide Y-immunoreactive nerves and a decrease in catecholamine-containing nerves compared with controls. The results are discussed in relation to autonomic neuropathy in diabetes. 相似文献
992.
JG O'Driscoll DJ Green † JM Rankin RR Taylor 《Clinical and experimental pharmacology & physiology》1999,26(10):779-783
1. Hypercholesterolaemia is associated with abnormal endothelium-related vasodilator function, possibly due to increased destruction .NO by superoxide anions (.O2-). Oxypurinol, a xanthine oxidase (XO) inhibitor with anti-oxidant properties and the active metabolite of the commonly used drug allopurinol, reduces .NO quenching in vitro and has been reported to acutely improve endothelial function in hypercholesterolaemic subjects. 2. The purpose of the present study was to determine whether oral allopurinol improves .NO dilator function in hypercholesterolaemic subjects. 3. A randomized double-blind, placebo-controlled cross-over design evaluated the effect of allopurinol (300 mg daily for 4 weeks) on forearm blood flow (FBF) responses to intrabrachial infusion of acetylcholine (ACh), sodium nitroprusside (SNP) and NG-monomethyl-L-arginine (L-NMMA) in nine hypercholesterolaemic subjects. 4. Endothelium-dependent vascular responses to ACh and L-NMMA were not significantly altered by allopurinol. The endothelium-independent vasodilator response to SNP was similarly unchanged. 5. These results indicate that allopurinol does not influence basal or stimulated activity of the .NO dilator system in hypercholesterolaemic subjects. If intracellular .O2- inactivation .NO is responsible for endothelial dysfunction in hypercholesterolaemia, the source may be other than XO dependent. However, generation of .O2- during the conversion of allopurinol to oxypurinol could offer an alternative, and probably more likely, explanation for the ineffectiveness of allopurinol in vivo. 相似文献
993.
This paper will examine how the narrative of one woman, Madeleine, can be constructed as symptomatic of the diagnosis of schizophrenia, and how it can also be read from other perspectives, particularly a poststructural feminist one. The readings are presented as possibilities for understanding the woman's experiences and the implications of this for mental health nursing practice. A poststructural feminist reading acknowledges the gendered experiences of subjectivity and how those experiences are constructed in language. The purpose of this paper is to identify for mental health nursing practice an approach which recognizes the figurative and literal characteristics of language in order to provide nursing care which positions the individual's experience of mental distress as central. This requires an acknowledgement of Madeleine's path into mental distress rather than simply a categorization of what is observed in a clinical setting. Intervention may need to include a range of strategies: medical and nonmedical, psychotherapeutic and social, physical and environmental. It may also require the provision of sanctuary and security whilst these options are explored. 相似文献
994.
995.
R M Macklis R L Crownover J Crowe T Willoughby J Sohn 《American journal of clinical oncology》1999,22(4):419-425
During a standard course of breast radiotherapy, the contralateral breast generally receives approximately 2.5 to 6.0 Gy of scattered radiation. Although most studies have not found an overall increase in metachronous contralateral breast cancers in patients undergoing radiotherapy, a cohort of younger women may be genetically more susceptible to radiation-induced breast cancers and may thus be adversely affected by the scattered radiation. We are attempting to develop a simple, convenient, effective mechanism for minimizing the scattered radiation to the contralateral breast during the process of clinical breast radiotherapy. We therefore designed a conformal, platform-based breast shield consisting of 2.5 cm of molded lead in a mobile counterweighted polystyrene casing. This shield was intended to serve as a physical barrier to prevent both low and high energy scattered photons from the medial and lateral tangential fields. We conducted a prospective trial of 20 women, each woman serving as her own control. Each woman received breast radiotherapy with and without shield, and an array of thermoluminescent dosimeters was positioned across the contralateral breast to evaluate the in vivo dosimetry and the impact of the breast shield on surface absorption of scattered radiation. We found that the use of the breast shield reduced the median dose of scattered radiation by approximately 60% (p < 0.0001). This represented a median dose reduction of approximately 300 cGy at the nipple. The shield was easily positioned and added < 1 min to daily setup time. We conclude that the use of this sort of surface barrier shielding technique was feasible, effective, and practical for clinical use. The degree of scatter reduction accomplished through the use of this breast shield may be biologically significant, especially for those patients with biologic or epidemiologic risk factors that may predispose them to the development of radiogenic breast cancers. 相似文献
996.
Begleiter H Reich T Nurnberger J Li TK Conneally PM Edenberg H Crowe R Kuperman S Schuckit M Bloom F Hesselbrock V Porjesz B Cloninger CR Rice J Goate A 《Genetic epidemiology》1999,17(Z1):S25-S30
Problem 1 of Genetic Analysis Workshop 11 consists of data from a family study of the genetics of alcoholism and related traits contributed by the six centers making up the National Institute for Alcohol Abuse and Alcoholism sponsored by the Collaborative Study on the Genetics of Alcoholism (COGA). The family data included 1,214 members of 105 pedigrees ascertained for having three or more individuals affected with alcoholism. Data available to workshop participants included clinical phenotypes, personality measures, smoking behavior, event-related potentials, platelet monamine oxidase B activity, and a genome scan of 296 markers. 相似文献
997.
There has been an increasing interest in developing vaccines which are both easy to administer and which elicit functionally protective immune responses at mucosal and/or systemic sites. Intranasally administered vaccines meet the criteria of ease of administration and are thought to stimulate respiratory-mucosal immunity via interaction with nasal associated lymphoid tissues (NALT). The aim of this study was to gain a better understanding of how best to stimulate respiratory-mucosal immunity using a murine model of respiratory reovirus infection. Either a predominantly upper respiratory tract infection or a combination upper and lower respiratory tract infection was established by administering the same virus dose in either a small or large inoculum volume. These studies demonstrate that stimulation of NALT alone by an upper respiratory tract infection does not induce an optimal primary antibody response even in the nasal cavity. Effective immunity of both the upper and lower respiratory tract was obtained when a combination upper and lower respiratory tract infection was established. These results have important clinical implications since they suggest that effective respiratory mucosal immunity will be best achieved by the combined stimulation of both the upper and lower respiratory tract and will likely require both intranasal as well as inhaled aerosol delivery of antigen to the lower respiratory tract in humans. 相似文献
998.
Gibbs A Mousseau TA Crowe JH 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(16):7257-7260
Epicuticular lipids provide the primary barrier to water loss in insects and other terrestrial arthropods. Using Fourier transform infrared spectroscopy, we found that the melting temperatures for these lipids in the grasshopper Melanoplus sanguinipes varied by over 10 degrees C between individuals. The most significant determinant of lipid melting temperature was geographic population, followed by family effects and rearing regime. The width of the phase transition also showed population and family effects. Differences in lipid phase properties were correlated with habitat temperature. Our results provide evidence for genetically based intraspecific variation in epicuticular lipids and have important implications for physiological studies of water balance in arthropods. 相似文献
999.
Dr. H. Paul Chalfant Ph.D. Dr. LeRoy O. A. Martinson Ph.D. Mr. Daniel J. Crowe M.S.W. 《Community mental health journal》1975,11(4):402-409
Although the use of recovering alcoholics as counselors in professional settings is increasing, there is little information on the factors important in selecting counselors. This study looks at previous occupational socialization as one such factor. On the basis of a study of alcoholism rehabilitation counselors and their supervisors in Indiana it has been concluded that such socialization is an important factor. It is recommended that prospective employers be wary of applicants without some experience in "bureaucratic" types of work experience, that is, who have not had experience in work settings or with work requirements somewhat analogous to those in the professional setting. 相似文献
1000.
Intravenous urographic technique 总被引:1,自引:0,他引:1
In these times of rapid advances in radiographic imaging, intravenous urography should be performed in an optimal way. The urographic examination should involve consultation between the referring physician and the radiologist. Necessary patient information should be accessible. McClennan said "patient selection for urographic studies should be efficacious with the radiologist exerting appropriate control so that the urogram is truly a consultative imaging service integrated into the total patient management." We share this view, and it is an extension of the philosophy of practice emphasized by other leaders in uroradiology. Cost containment, new imaging technologies, risk/benefit considerations, and evolving patterns of patient care have had a significant influence on genitourinary tract imaging. In addition, current debate about contrast media, digital radiography, efficacy, and utilization will undoubtedly have an influence on imaging during the next decade. Utilization of intravenous urography has decreased significantly in the past 15 years. Our volume of examinations has declined approximately 50% since 1970. This decline in our practice is attributed to several complex factors such as previous overutilization of screening urography for hypertension; the impact of US and CT for evaluation of obstruction, retroperitoneal disease (adenopathy and fibrosis), renal failure, and renal masses; concern about contrast medium-induced renal failure; and fewer repeat studies because of improved quality of intravenous urography in general radiology practice. In addition, overutilization of urography in patients with hematuria, prostatism, history of urinary tract infection, etc, continues to be debated in the medical community. In our integrated group practice, we have also observed overutilization of "high-tech" procedures in lieu of urography for evaluation of suspected urinary tract disease. Swings of the pendulum are inevitable in diagnostic imaging because of evolving technology and the art of medical practice. Although some differences of opinion about the details of urographic technique and indications for urography may exist, most would agree on the philosophy of producing a high-quality urographic examination. That philosophy focuses on producing the highest quality examination in each patient so that a diagnosis of normal or abnormal can be made accurately and confidently. Failure to demonstrate the entire urinary tract is a common cause of diagnostic error and one that can largely be eliminated by careful attention to the technical details of the examination. 相似文献