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991.
Pheochromocytoma is rarely observed during pregnancy and not easily diagnosed, especially since the clinical manifestations may mimic common gravid hypertension. The maternal and fetal prognosis depends on early diagnosis and multidisciplinary management preparing for tumor resection. Appropriate laboratory tests easily provide the positive diagnosis, if they are ordered. The tumor is localized by ultrasonography or magnetic resonance imaging (MRI). By prescribing an alpha-blocker, it is possible to prepare the resection as a function of term, before or after delivery. This strategy allows a reduction in maternal and fetal mortality which is high if the pheochromocytoma goes undiagnosed.  相似文献   
992.
OBJECTIVE: To determine if gabapentin is effective either as adjunctive treatment or as monotherapy for major affective disorders in a naturalistic setting. METHOD: All charts of patients meeting DSM-IV criteria for bipolar disorder or unipolar major depressive disorder treated with gabapentin in a private psychiatric practice were reviewed and clinical response was assessed retrospectively using the Clinical Global Impressions scale for Improvement (CGI-I). RESULTS: Gabapentin was moderately to markedly effective in 30% (15/50) of patients, with statistically nonsignificant differences between patients with bipolar disorder type I, bipolar disorder type II and NOS, and unipolar major depressive disorder. 70% reported side effects, mainly sedation, with 16% of the total sample discontinuing treatment due to adverse events. CONCLUSION: Gabapentin appears to be somewhat effective as add-on treatment in a subgroup of patients with mood disorders in a naturalistic setting. Prospective, controlled studies are required to clarify these pilot data.  相似文献   
993.
CONCEPT: No consensus exists regarding the magnitude of the risk of noise-induced hearing loss (NIHL) associated with leisure noise, in particular, personal listening devices in young adults. OBJECTIVE: Examine the magnitude of hearing loss associated with personal listening devices and other sources of leisure noise in causing NIHL in young adults. STUDY DESIGN: Prospective auditory testing of college student volunteers with retrospective history exposure to home stereos, personal listening devices, firearms, and other sources of recreational noise. METHODS: Subjects underwent audiologic examination consisting of estimation of pure-tone thresholds, speech reception thresholds, and word recognition at 45 dB HL. RESULTS: Fifty subjects aged 18 to 30 years were tested. All hearing thresholds of all subjects (save one-a unilateral 30 dB HL threshold at 6 kHz) were normal, (i.e., 25 dB HL or better). A 10 dB threshold elevation (notch) in either ear at 3 to 6 kHz as compared with neighboring frequencies was noted in 11 (22%) subjects and an unequivocal notch (15 dB or greater) in either ear was noted in 14 (28%) of subjects. The presence or absence of any notch (small or large) did not correlate with any single or cumulative source of noise exposure. No difference in pure-tone threshold, speech reception threshold, or speech discrimination was found among subjects when segregated by noise exposure level. CONCLUSION: The majority of young users of personal listening devices are at low risk for substantive NIHL. Interpretation of the significance of these findings in relation to noise exposure must be made with caution. NIHL is an additive process and even subtle deficits may contribute to unequivocal hearing loss with continued exposure. The low prevalence of measurable deficits in this study group may not exclude more substantive deficits in other populations with greater exposures. Continued education of young people about the risk to hearing from recreational noise exposure is warranted.  相似文献   
994.
Technetium-99m-hexamethylpropylene amine oxime (HMPAO) brain images with fanbeam SPECT, in combination with surface three-dimensional display, were used to detect basal ganglion and cerebral cortex anomalies in the acute phase of carbon monoxide (CO) poisoning. METHODS: Ten patients, aged 16-29 yr, with acute CO poisoning and no past history of neurologic disorders were enrolled in this study. After oxygen treatment, all 10 patients were investigated using 99mTc-HMPAO brain images with fanbeam SPECT and surface three-dimensional display. Meanwhile, 6 of 10 patients also received a brain CT scan. RESULTS: CT scan findings were negative in all 6 patients. Fanbeam SPECT demonstrated unilateral or bilateral hypoactivity of basal ganglia in 6 patients. Local hypoactivity anomalies were found in the brain cortex of 7 patients, using surface three-dimensional display of the brain. Only 2 of 10 patients had normal 99mTc-HMPAO brain images. CONCLUSION: This study suggests that, in comparison with traditional brain imaging techniques, 99mTc-HMPAO brain imaging with fanbeam SPECT in combination with surface three-dimensional display is a better tool for early detection of regional cerebral anomalies in acute CO poisoning.  相似文献   
995.
With AIDS related tuberculosis in the pediatric population on the rise, we review our experience with 14 such children. A brief review of the pertinent literature is also presented.  相似文献   
996.
核设施退役过程中辐射测量的一般问题   总被引:2,自引:1,他引:1  
黄治俭  滕慧洁 《辐射防护》1996,16(2):103-108
本文叙述了设施退役的阶段划分和退役过程吕辐射测量的一些问题,主要包括退役前源项调查中辐射测量的目的、内容和方法,退役施工过程中的施工辐射监测,以及退役施工结束后终态辐射检测和终态验收检测的有关问题。  相似文献   
997.
The present study assessed fidelity to the behavioral family management (BFM) model for treating bipolar disorder patients and their families. The BFM Therapist Competency/Adherence Scale (BFM-TCAS) was developed to evaluate clinicians' competency and adherence to BFM, as outlined by Miklowitz' (1989) BFM Manual for use with bipolar patients. Therapist competency and treatment adherence was also evaluated with regard to two family characteristics: overall level of family difficulty and family expressed emotion (EE) status. The BFM-TCAS was used to code 78 videotaped sessions of 26 families with a bipolar member, selected from a larger treatment study of bipolar disorder patients. The findings suggest that, overall, clinicians adhered closely to the BFM manual. Specific areas in which there was high competency and treatment adherence were (a) skill in conveying factual information about bipolar illness, (b) establishment of a therapeutic environment, and (c) ability to take command of therapy sessions. The one area in which there was less competency and relatively weak adherence to the manual was the use of between-session homework assignments to assist families in mastering the BFM exercises. Results of this study also suggest that, for the most part, therapist competency and adherence ratings were not related to overall level of difficulty or to family EE status.  相似文献   
998.
Retinoic acid (RA) has been implicated in cardiac morphogenesis by its teratogenic effects on the heart, although its role in normal cardiogenesis remains unknown. To define the parameters of RA action in cardiac morphogenesis, we analyzed the patterns of ligand synthesis, response, and inactivation in the developing mouse heart. Activation of a lacZ transgene controlled by an RA response element (RARE) was compared to the localization of the retinaldehyde-oxidizing dehydrogenase RALDH2, the earliest RA synthetic enzyme in the mouse embryo, and to the expression of a gene encoding an RA-degrading enzyme (P450RA). We observed that RALDH2 localization and RA response were virtually superimposable throughout heart development. Initially, both RALDH2 and RARE-LacZ activity were restricted to the sinus venosa in unlooped hearts, but were high in the dorsal mesocardium, while P450RA expression was restricted to the endocardium. Later stages were characterized by a sequential, noncontiguous progression of RALDH2 accumulation and RA response, from the sinus venosa to atria, dorsal-medial conotruncus, aortic arches, and the epicardium. This dynamic pattern of RA response was a direct result of localized RALDH2, since hearts of cultured embryos were uniformly competent to respond to an exogenous RA challenge. These observations support a model in which the influence of endogenous RA on heart development depends upon localized presentation of the ligand, with only limited diffusion from the source of its synthesis.  相似文献   
999.
The efficacy and safety of optimally titrated once-daily (CD) and twice-daily (SR) diltiazem were compared in 111 patients with mild to moderate systemic hypertension [seated diastolic blood pressure (DBP) > or = 95 mmHg and < or = 114 mmHg] in a multicenter, randomized, double-blind, placebo run-in, parallel-group trial. Following a 4 week washout and placebo-controlled run-in period, patients were randomized to receive diltiazem CD 180 mg and matching placebo (n = 54), or diltiazem SR 90 mg bid (n = 57). Total daily doses were titrated from 180 mg to 360 mg to achieve a goal of seated DBP < 90 mmHg during a 6 week titration period. The patients continued to receive their optimal dose for a 6 week follow-up period. Ninety-six (96) patients (diltiazem CD: 47, diltiazem SR: 49) completed the study protocol, with 60% of the diltiazem CD and 55% of the diltiazem SR patients achieving the goal of seated DBP of < 90 mmHg (p = 0.685). Although significant decreases occurred in seated and standing measurements of diastolic and systolic BP and heart rate with treatment in both groups, there were no significant differences between treatment groups. Both medications were well tolerated, with a similar frequency of adverse effects [diltiazem CD: 24/54 (37%) patients; diltiazem SR: 24/57 (42.1%) patients] with the most frequently reported adverse effects being headache and edema.  相似文献   
1000.
One case of non-penetrance of the familial adenomatous polyposis (FAP) gene at 59 years of age and late onset of polyps on endoscopy and biopsy in this and two other families is described. Screening protocols should include dental screening as well as indirect ophthalmoscopy and endoscopy to detect minimal manifestations of the gene. In the absence of a specific DNA predictive test, bowel screening should continue well beyond 30 years of age.  相似文献   
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