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1.
2.
Thirteen patients who have suffered a "near-miss" death of asthma have been compared to 36 patients with asthma who had not experienced such an episode. Contrary to expectations, there were no differences between the groups in their levels of psychiatric morbidity, their degree of life-style and social restrictions or in their levels of compliance with prescribed medication. However, both groups did show higher than expected levels of psychiatric morbidity, severe life-style and social restrictions and an unexpectedly-high compliance with prescribed medication. The main psychiatric diagnoses that were noted were anxiety disorders. It is concluded that more comprehensive asthma education and close medical follow-up are likely to improve the physical and psychological health of asthmatic patients. The high-risk patients in this study who received such follow-up have shown hospital-admission rates that have been reduced by a half while maintaining good asthma control. This South Australian longitudinal study is continuing.  相似文献   
3.
Circulating angiotensin II acts on neurons in circumventricular organs, leading to activation of central pathways involved in blood pressure regulation and body fluid homeostasis. Apart from this primary effect, an increase in the level of circulating angiotensin II may also activate brain neurons as a secondary consequence of the associated increase in blood pressure, which will stimulate arterial baroreceptors and thus activate central neurons that are part of the central baroreceptor reflex pathway. The aim of this study was to identify the population of neurons that are activated as a consequence of the direct actions of circulating angiotensin II on the brain, independent of secondary baroreceptor-mediated effects. For this purpose, we have mapped the distribution of neurons in the brainstem and forebrain that are immunoreactive for Fos (a marker of neuronal activation) following intravenous infusion of angiotensin II in conscious rabbits with chronically denervated carotid sinus and aortic baroreceptors. The distribution was compared with that evoked by the same procedure in two separate groups of barointact rabbits, in which angiotensin II was infused either at a rate similar to that in the barodenervated group, or at a rate approximately five times greater. In barodenervated rabbits, angiotensin II infusion evoked a significant increase in Fos expression, compared to control animals infused with the vehicle solution alone, in several forebrain nuclei (organum vasculosum of the lamina terminalis, subfornical organ, median preoptic nucleus, supraoptic nucleus, paraventricular nucleus, bed nucleus of the stria terminalis and suprachiasmatic nucleus), but little or no increase in Fos expression in any lower brainstem region. In barointact rabbits infused with angiotensin II at a similar rate to that in barodenervated rabbits, a similar degree of Fos expression was evoked in all of the above forebrain regions, but in addition a significantly greater degree of Fos expression was evoked in several medullary regions (nucleus tractus solitarius, area postrema, and ventrolateral medulla), even though the angiotensin II-evoked increase in mean arterial pressure (17 +/- 3 mmHg) was less than that evoked in the barodenervated rabbits (26 +/- 2 mmHg). In barointact rabbits infused with angiotensin II at the higher rate, the increase in mean arterial pressure was 29 +/- 3 mmHg. In these animals, the pattern of Fos expression was similar to that evoked in barointact rabbits infused at the lower rate, but the degree of Fos expression in all medullary regions and in some forebrain regions was significantly greater. The results of the present study, together with those of previous studies from our laboratory in which we determined the effects of phenylephrine-induced hypertension on brain Fos expression [Li and Dampney (1994) Neuroscience 61, 613-634; Potts et al. (1997) Neuroscience 77, 503-520], indicate that in conscious rabbits circulating angiotensin II activates primarily circumventricular neurons within the organum vasculosum of the lamina terminalis and subfornical organ, but not the area postrema, and this in turn leads to activation of neurons in other forebrain regions, including the median preoptic, supraoptic, paraventricular and suprachiasmatic nucleus as well as the bed nucleus of the stria terminalis. In contrast, the activation of neurons in medullary regions evoked by an increase in the level of circulating angiotensin II is primarily a secondary effect resulting from stimulation of arterial baroreceptors.  相似文献   
4.
Autosomal dominant polycystic kidney disease is one of the most common hereditary diseases, and frequently has well defined extrarenal manifestations. Very few cases of aortic aneurysms associated with this disorder are described in literature. We report a 42-year-old male with autosomal dominant polycystic kidney disease presenting with dissecting aneurysm of the thoracic aorta.  相似文献   
5.
PURPOSE: To assess internal medicine and general surgery residents' attitudes about the effects of the Accreditation Council for Graduate Medical Education duty hours regulations on medical errors, quality of patient care, and residency experiences. METHOD: In 2005, the authors surveyed 200 residents who trained both before and after duty hours reform at six residency programs (three internal medicine, three general surgery) at five academic medical centers in the United States. Residents' attitudes about the effects of the duty hours regulations on the quality of patient care, residency education, and quality of life were measured using a survey instrument containing 19 Likert scale questions on a scale of 1 to 5. Survey responses were compared using the Student's t-test. RESULTS: The response rate was 80% (159 residents). Residents reported that whereas fatigue-related errors decreased slightly, errors related to reduced continuity of care significantly increased. Additionally, duty hours regulations somewhat decreased opportunities for formal education, bedside learning, and procedures, but there was no consensus that graduates would be less well trained after duty hours reform. Residents, particularly surgical trainees, reported improvements in quality of life and reduced burnout. CONCLUSIONS: Residents in medicine and surgery had similar opinions about the effects of duty hours reform, including improved quality of life. However, resident opinions suggest that reduced fatigue-related errors have been offset by errors related to decreased continuity of care and that the quality of the educational experience may have declined. Quantifying the degree to which regulating duty hours affected errors related to discontinuity of care should be a focus of future research.  相似文献   
6.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
7.
Potts M 《Lancet》1990,336(8722):1059-1060
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8.
It is generally accepted that the stratum corneum (SC) is the least permeable layer of the epidermis. Histologically, though, the SC is a non-uniform, inhomogeneous membrane, and the question "Is barrier function distributed uniformly across the SC thickness?" has been posed. To address this issue, human ventral forearm SC has been studied in vivo by attenuated-total-reflectance Fourier-transform infrared spectroscopy during the course of sequential tape-stripping. Because the intercellular lipids of the SC and the degree of hydration of the membrane have been shown to be crucial determinants of barrier function, attention has been focused on the spectral features, which report specifically on these parameters. The degree of disorder of the SC intercellular lipids has been found to decrease over the outer cell layers (up to three tape-strips) and then to remain essentially constant. The amount of lipids decreases similarly such that a 60% reduction (relative to the "no-strip" baseline) is observed after about four tape-strips. A plausible explanation for these measurements is that the lipids near the surface are a mixture of (a) "true" intercellular lipid (which is expected to be highly ordered), and (b) sebaceous lipid (which contains much greater amounts of low-melting components, such as fatty acids). The sequential infrared (IR) spectra provide at least circumstantial evidence to support this hypothesis. As expected, the IR spectra show that SC hydration increases from the surface towards the SC-stratum granulosum interface. Taken together, the results imply that the SC is indeed non-uniform. The properties of the outer layers (those removed by the first 3-4 tape-strips) change significantly with increasing depth.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
  • 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
  • 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
  • 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
  • 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.
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10.
The current and potential role of males in family planning is often underestimated. The use of female contraceptive methods tends to require more outside assistance than the use of male methods; therefore, the role of males is less visible and harder to document. Furthermore, males often exert considerable influence over their wives' contraceptive choices but this influence is exerted in the privacy of the home rather than in clinical settings. The value of condoms and of male sterilization procedures is also underrated. The condom is effective, is not associated with negative side effects, and is easy to distribute and to use. In addition, it provides protection from sexually transmitted diseases. Its use should be encouraged. Vasectomies, compared to female sterilization procedures, are simpler to perform and are associated with fewer complications. Efforts to simplify vasectomies even further are also being made. Investigators are currently attempting to occlude the vas by injecting a mixture of alcohol and formaldehyde through the skin. Other investigators continue their efforts to develop a male contraceptive pill; however, since males produce new sperm throughout their reproductive life span, it is more difficult to induce infertility in men than in women. The use of drugs to inhibit sperm production may also induce sperm maturations. Clinical trials of alpha chlorhydrin, which interferes with the sperm maturation process have been conducted, and in 1978 the Chinese began to use gossypol to suppress sperm production. Most of the male contraceptive agents currently being investigated offer little promise and it may be at least 10 years before an effective male pill is produced.  相似文献   
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