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61.
OBJECTIVES: To assess self-reported knowledge, attitudes, and behaviors of practicing community family physicians regarding identification and management of depression in late life. DESIGN: We sent a 3-page "fax-back" survey to 768 active physician members of the Maryland Academy of Family Physicians, Baltimore. MEASUREMENTS: We asked physicians to rate how confident they felt in evaluating several common medical conditions of late life, including depression. The questionnaire included items related to knowledge and treatment practices for depression in older adults. RESULTS: Two hundred fifteen usable surveys were returned. In general, physicians took responsibility for diagnosing and treating depression. Few physicians reported that they routinely referred the older patient to a psychiatrist to treat depression, and only half thought that consultation was helpful. Physicians responding to the survey were generally aware of alternative presentations of depression in elderly persons, and were well informed about the duration of treatment with medications for depression. Most were using selective serotonin reuptake inhibitors as first-line agents to treat depression. Physicians though that medications for depression were as effective for older patients as for younger patients, but were less optimistic about the effectiveness of psychotherapy. The barriers to identifying and treating depression in older patients most often mentioned by physicians were related to the atypical presentation of depression in older adults. More than half of the physicians rated themselves as "very confident" in evaluating depression. There were few differences in the responses of physicians with and those without a Certificate of Added Qualifications in geriatrics. CONCLUSIONS: Depression in late life remains a difficult clinical challenge for primary care physicians. These findings are particularly relevant in the face of recent efforts to increase collaboration between primary care physicians and mental health professionals.  相似文献   
62.
In 1996 the Navarra Occupational Health Institute, an autonomous technical organization that integrates the functions and means related to occupational health matters, drew up the Occupational Health Diagnosis of Navarra, which is a region characterised by its important industrial sector and its high proportion of small and medium size companies. The results emphasise the high accident rate in the construction sector, the constant increase of professional diseases through "fatigue of tendon pods", as well as the importance of osteo-muscular processes as a cause of temporary and permanent disability. Forty sentinel occupational tumors, mainly mesothelioma, and 27 Obligatory Statement Diseases of occupational origin, mainly brucellosis, were identified in a period of seven years and three years, respectively. Verification was made of a lack of systematised information about population exposure to occupational risks, a scarce development of medical surveillance of exposed workers, and a lack of information about the incidence of occupational injuries in self-employed workers.  相似文献   
63.
This article summarizes the organization, financing, and delivery of health care services in Spain, and discusses the elements that made it possible to maintain high levels of health among the population, while spending comparatively fewer resources on the health care system than most industrialized countries. The case of Spain is of particular interest for newly industrialized countries, because of the fast evolution that it has undergone in recent years. Considered, by United Nations' economic standards, a developing country until 1964, Spain became in a few years the fastest growing economy in the world after Japan. By the early 1970s the infant mortality rate was already lower than in Britain or the United States.  相似文献   
64.
Gonadal steroid hormones influence vascular tone and the development of hypertension. There are sex differences in the incidence of cardiovascular diseases, and great attention has been placed on the study of estrogen cardiovascular effects. However, there are only a few reports on the effects of testosterone on the vasculature. It is commonly accepted that the mechanism of the action of steroid hormones on target tissues is mediated through the binding of hormones to cytoplasmic or nuclear receptors. However, some studies indicate that steroid action can be extremely rapid and therefore unlikely to be through a genomic mechanism. The purpose of this study was to assess the effect of intravascularly confined testosterone on an isolated rat heart to demonstrate acute and possibly nongenomic effects of the steroid. Our results show that testosterone blocked the adenosine vasodilator effect and increased vascular resistance, even when its presence was restricted to the coronary vascular lumen. These effects were exerted rapidly and possibly through nongenomic mechanisms.  相似文献   
65.
Assessment of exercise capacity has been widely used in the evaluation of chronic heart failure (CHF), both to define the severity of the syndrome and to assess the changes induced by therapy. Various exercise tests and protocols can be used. The simple stress test using the exercise bicycle or the treadmill can give useful indications only in patients with severe or lower functional reductions. Maximum exercise duration usually depends on the patient's and the physician's motivation. The addition of respiratory gas exchange measurements, maximum oxygen consumption (VO(2)) or anaerobic threshold, increases the exactness of the assessment of the exercise limitation in CHF. VO(2) maximum provides an objective marker of aerobic capacity and it is biased by neither the patient nor the physician. This technique, however, requires the patient to exercise to exhaustion, and it is somewhat subjective and not indicative of normal daily exercise routine. The anaerobic threshold is a useful way of evaluating adaptability to submaximal efforts and the impact of the therapy on the daily performance. Nevertheless, it is significantly influenced by the fitness level and it has a reduced prognostic capability compared to VO(2) maximum. Submaximal exercise tests discriminate particularly between patients with severe CHF. The major limits are the influence of the patient's motivation and its limited validation in terms of reproducibility and prediction in controlled surveys.  相似文献   
66.
Left ovaries of bursectomized chick embryos were examined on the 17th day of incubation in comparison to normal and sham-operated controls, by histological and histochemical observations. The results show that in bursectomized embryos the cortex appears irregulary developed, with a significant decrease in the mean thickness and in the percentage of the secondary sex cords in the total cortical area. Furthermore, the germinal epithelium appears thicker and the subcortical medulla and the tunica albuginea more compact. The greater activity of the enzyme 5–3-hydroxysteroid dehydrogenase ( 53HSD) found in ovaries of bursectomized embryos (histochemical method) could be related to an endocrine dismetabolism affecting the cortical development. On the basis of these results and those of other authors, some hypotheses are advanced. In particular, an action of the bursal factor on GTH receptors could be the factor responsible of the enhanced steroidogenic activity altering the hormonal environment.  相似文献   
67.
Brain delivery of active anti-HIV compounds is important for successful treatment of the AIDS patient. As an initial step in predicting human brain drug concentrations, hybrid pharmacokinetic models were developed to characterize the disposition of anti-HIV nucleosides following parent and prodrug administrations in mice. Mouse data were obtained following intravenous administration of 3-azido-2,3-dideoxyuridine (AZddU or AZDU), 3-azido-3-deoxythymidine (AZT), and their dihydropyridine prodrugs (AZddU-DHP and AZT-DHP). Exponential equations were fitted to the serum concentration–time data for each species, including the pyridinium ion moieties, and subsequently used in differential mass balance equations describing the brain dynamics of each compound. Model parameters for the mass balance equations were estimated by various techniques, including the utilization of in vitro data. In general, model-predicted brain concentrations agreed with the observed data. Similar data in larger animals will permit scale-up of the current model to predict human brain drug concentrations.  相似文献   
68.
A combined emulsion/polymer cross-linking/solvent evaporation technique was used to prepare magnetic chitosan microspheres (MCM) containing the anticancer drug, oxantrazole. A central composite experimental design was used to simultaneously evaluate a variety of formulation factors on a number of response variables, such as the percentage of oxantrazole entrapped in the MCM. In association with the study design, statistical optimization procedures indicated the factors that significantly influence MCM preparation and what levels of the factors are needed to produce optimum MCM. Entrapment of anticancer agents into biodegradable microspheres is difficult because of low aqueous drug solubility and porosity of the particles. The latter effect was circumvented by a chitosan cross-linking step that resulted in 3% (w/w) oxantrazole entrapment in the MCM via the optimization procedures. The combined formulation and statistical optimization strategy provide a basis to develop other microparticulate systems and led to a dosage form that can be used for future in vivo investigations.  相似文献   
69.
Summary In three general medical settings (general practice, hospital medical wards and emergency rooms) about 20% of the adult attenders had a DSM-III mental disorder, mainly in the area of affective and anxious disorders. Some of these disorders were quite severe. Of those cases reassessed 1 year and 2 years after the first interview, less than a quarter reached a no-diagnosis status. The chronicity of most cases dependent on the interplay not only of either relapse or duration of the main disorder but also of comorbidity and incidence of new disorders. A high incidence of more transient disorders in subjects who were well at first assessment was also found.  相似文献   
70.
OBJECTIVE: Research studies on the validity of current diagnostic and subthreshold categories of depression that use a population-based follow-up design are rare. The authors examined the validity and utility of four current depression categories by examining subject transition between categories and the symptoms, course, and risk factors of each. METHOD: A general population sample of 1,920 adults from the Baltimore Epidemiologic Catchment Area 13-year follow-up study were examined. Data on diagnoses, symptoms, course, and risk factors were collected by using the National Institute of Mental Health Diagnostic Interview Schedule, the Life Chart Interview, and an office visit. Polychotomous regression was used to examine the heterogeneity of four diagnostic categories: major depressive disorder, depressive syndrome, dysthymia, and a comorbid depression condition (major depressive disorder and dysthymia). RESULTS: Transitions between the four depression categories occurred over the 13 years. Symptom profiles for the four categories were parallel but differed in severity. Course characteristics among the four categories slightly differed. Risk factor profiles showed significant differences. Family history was associated with both depressive syndrome and major depressive disorder. Stressful life events were most strongly associated with depressive syndrome. Female gender was most strongly associated with the comorbid depression category. CONCLUSIONS: The evidence suggests that except for dysthymia, the depression categories are genetically homogeneous and environmentally heterogeneous. Stress is associated with mild depression, and gender is associated with severe depression. The apparent familial transmission of the subthreshold entity, depressive syndrome, needs further investigation.  相似文献   
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