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131.
BACKGROUND: This prospective study was designed to determine whether patients with prophylaxis-resistant affective disorders, receiving adjunctive maintenance therapy with supraphysiological doses of levothyroxine (L-T4), show evidence of accelerated bone loss compared to the reference population database. METHODS: In 21 patients, bone mineral density (BMD) of the spine (lumbar vertebrae L1-L4) and femur (femoral neck, trochanter, and Ward's triangle) was measured by dual energy X-ray absorptiometry (DXA). BMD measurement was performed first after patients had been on thyroid-stimulating hormone (TSH)-suppressive therapy with L-T4 (mean dose=411 mcg/d) for an average of 16.4 months and again after 33.6 months of L-T4 (mean dose=416 mcg/d) therapy. RESULTS: There was no statistically significant difference between the actual percentage decline in bone mineral density and the expected percentage decline in any of the measured bone regions. In a stepwise linear regression analysis, age was identified as a predictor of percentage change in BMD. After controlling for age, the only other variable that showed a consistent trend was the dose of L-T4, with higher doses being positively correlated with the percentage decline of BMD. LIMITATIONS: Relatively small sample size, no bone density assessment prior to treatment with L-T4, no patient control group with mood disorders who did not receive L-T4 treatment, and bone density follow-up intervals were variable. CONCLUSIONS: This study did not demonstrate evidence that long-term treatment of affectively ill patients with supraphysiological doses of L-T4 significantly accelerates loss of bone mineral density compared to the age-matched reference population. However, the decline of BMD in one individual patient underscores that caution is indicated and that regular assessment of BMD during longer-term supraphysiological thyroid hormone treatment is needed.  相似文献   
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OBJECTIVE: To examine the relation between baseline measurements of thyroid function and response to selective serotonin reuptake inhibitors (SSRIs) and to consider the effect of these antidepressants on thyroid hormone levels. METHODS: Nineteen subjects with major depression, but without a history of thyroid treatment or lithium treatment, were treated openly with either sertraline or fluoxetine in a university- affiliated tertiary care hospital. Hamilton Depression Rating Scale (Ham-D) scores were measured before and after treatment. Clinical Global Impressions (CGI) scores were measured at study end. Thyroid data, consisting of values for thyroid-stimulating hormone (TSH), triiodothyronine (T(3), measured by radioimmunoassay [RIA]), thyroxine (T(4), measured by RIA) and free T(4), were collected before and after treatment. Complete thyroid data were available for 17 subjects. Data were collected during 1997-1999. RESULTS: Baseline TSH correlated strongly with response to treatment as measured by change in Ham-D scores (r = 0.64, p = 0.003). Low TSH values correlated with greater improvement in depressive symptoms. Thyroid hormone levels decreased with treatment, but these decreases did not correlate with clinical improvement. CONCLUSION: Baseline thyroid function, as measured by serum TSH, may predict a patient's response to antidepressant treatment with SSRIs. Optimal thyroid function, beyond simply being within the normal laboratory values, may be necessary for an optimal response to antidepressants.  相似文献   
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Systemic administration of analgesics can lead to serious adverse side effects compromising therapeutic benefit in some patients. Information coding pain transmits along an afferent neuronal network, the first synapses of which reside principally in the spinal cord. Delivery of compounds to spinal cord, the intended site of action for some analgesics, is potentially a more efficient and precise method for inhibiting the pain signal. Activation of specific proteins that reside in spinal neuronal membranes can result in hyperpolarization of secondary neurons, which can prevent transmission of the pain signal. This is one of the mechanisms by which opioids induce analgesia. The spinal cord is enriched in such molecular targets, the activation of which inhibit the transmission of the pain signal early in the afferent neuronal network. This review describes the pre-clinical models that enable new target discovery and development of novel analgesics for site-directed pain management.  相似文献   
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PURPOSE: Night call is a significant part of residents' education, but little information about their night-call activities is available. This study recorded residents' activities during night-call rotations on internal medicine and pediatrics wards. METHOD: In June and July 1997, on-call pediatrics and internal medicine residents at an urban academic medical center were accompanied by trained observers on the general wards between the hours of 7 PM and 7 AM. The types and duration of activities were recorded. RESULTS: Residents were observed for 106 nights. Internal medicine and pediatrics residents spent their time similarly. They spent 5.3 hours and 5.7 hours per night, respectively, on "basic" activities such as eating, resting, chatting, and sleeping, and an average of 2.6 hours and 2.2 hours, respectively, on chart review and documentation. In both programs, discussing the case with team members averaged 1.5 hours per night and use of the computer averaged slightly more than half an hour. Internal medicine residents spent approximately 1.5 hours on patients' history and physical examinations while pediatrics residents spent 1.3 hours. With each new patient, internal medicine residents spent an average of 19.7 minutes and pediatrics residents spent 16.5 minutes. The only significant difference between the two groups of residents was that the pediatrics residents spent more time per night on procedures than did the internal medicine residents (37 minutes versus 14 minutes, p < 0.01). CONCLUSIONS: Residents from both programs spent a surprising amount of time each night on chart review and documentation. In fact, they spent more time with charts than with patients. Whether this activity truly contributes to residents' education or improved patients' outcomes is not clear.  相似文献   
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目的:探讨HBV-DNA复制水平与肝纤维化之间的相关性。方法:对210例慢性乙型肝炎患者进行HBV-DNA和肝纤维化血清学标志透明质酸(HA)、层粘蛋白(LN)、III型前胶原(PCIII)、IV型胶原(IV-C)进行定量检测。应用SPSS10.0统计软件对结果数据进行分析处理。结果:随慢性乙肝临床类型的加重,肝纤维化血清学标志逐渐升高(P<0.01),而肝纤维化血清学标志与HBV复制水平呈正相关(P<0.05);结论:HBV复制水平与肝纤维化之间呈正相关。  相似文献   
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In the December issue of the Archives, Nickerson et al published an article on the manpower resources of otolaryngology based on a report released in 1975. The conclusion reached by Nickerson and co-workers was that otolaryngology had a manpower pool too big for present and near future needs. This article was followed by a press release by the American Medical Association that endorsed the statements of the Archives article and in which Nickerson et al were quoted that no more otolaryngologists were needed from the training programs for some years. These statements were in sharp disagreement with the findings of the manpower studies carried out by another group in 1973-1975. Because the two surveys employed different statistical approaches, this article has been written to present the methods employed and to discuss the merits of the conclusions reached in each.  相似文献   
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