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71.
OBJECTIVE: Testosterone supplementation may produce antidepressant effects in men, but until recently it has required cumbersome parenteral administration. In an 8-week randomized, placebo-controlled trial, the authors administered a testosterone transdermal gel to men aged 30-65 who had refractory depression and low or borderline testosterone levels. METHOD: Of 56 men screened, 24 (42.9%) displayed morning serum total testosterone levels of 350 ng/dl or less (normal range=270-1070). Of these men, 23 entered the study. One responded to an initial 1-week single-blind placebo period, and 22 were subsequently randomly assigned: 12 to 1% testosterone gel, 10 g/day, and 10 to identical-appearing placebo. Each subject continued his existing antidepressant regimen. Ten subjects receiving testosterone and nine receiving placebo completed the 8-week trial. RESULTS: The groups were closely matched on baseline demographic and psychiatric measures. Subjects receiving testosterone gel had significantly greater improvement in scores on the Hamilton Depression Rating Scale than subjects receiving placebo. These changes were noted on both the vegetative and affective subscales of the Hamilton Depression Rating Scale. A significant difference was also found on the Clinical Global Impression severity scale but not the Beck Depression Inventory. One subject assigned to testosterone reported increased difficulty with urination, suggesting an exacerbation of benign prostatic hyperplasia; no other subject reported adverse events apparently attributable to testosterone. CONCLUSIONS: These preliminary findings suggest that testosterone gel may produce antidepressant effects in the large and probably underrecognized population of depressed men with low testosterone levels.  相似文献   
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Urine specimens from patients diagnosed with neurotoxic shellfish poisoning (NSP) were examined for biomarkers of brevetoxin intoxication. Brevetoxins were concentrated from urine by using solid-phase extraction (SPE), and analyzed by enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine extracts were fractionated by LC, and fractions analyzed for brevetoxins by ELISA. In subsequent LC-MS/MS analyses, several brevetoxin metabolites of B-type backbone were identified, with elution profiles consistent with those of ELISA. The more abundant brevetoxin metabolites in urine were characterized structurally by LC-MS/MS. With the exception of BTX-3, brevetoxin metabolites in urine differed from those found in shellfish and in shellfish meal remnants. Proposed structures of these major urinary metabolites are methylsulfoxy BTX-3, 27-epoxy BTX-3, and reduced BTX-B5. BTX-3 was found in all specimens examined. BTX-3 concentrations in urine, as determined by LC-MS/MS, correlated well with composite toxin measurements by ELISA (r(2)=0.96). BTX-3 is a useful biomarker for confirmation of clinical diagnosis of NSP.  相似文献   
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BACKGROUND: Fluid aspiration, percutaneous biopsy, and catheter drainage are standard minimally invasive methods of diagnosing lymphoma or leukemia in adults. OBJECTIVE: To determine the effectiveness of interventional radiologic techniques in diagnosing specific hematologic malignancies in children. METHODS: During a 4-year period, 22 patients (16 male, 6 female; median age, 13 years) underwent 25 percutaneous biopsies, 6 fluid aspirations, 3 catheter drainages, and 1 needle localization for diagnosing suspected hematologic malignancy. RESULTS: For Hodgkin's disease, the procedures yielded 6 true-positive (TP) results, 2 true-negative (TN) results, and 2 false-negative (FN) results; for non-Hodgkin lymphoma (NHL), 14 TP results, 1 TN result, and 3 FN results; and for leukemia, 4 TP results and 3 FN results. Percutaneous biopsies yielded 16 TP results, 3 TN results, and 6 FN results. Aspirations and drainages yielded 8 TP results and 1 FN result. The one needle localization yielded a FN result. Overall sensitivity was 75%+/-7.3%; specificity, 100%; and accuracy, 77%+/-7.1%. CONCLUSION: Percutaneous biopsy of lymphoma is usually diagnostic. Drainage or aspiration of a fluid collection associated with NHL or leukemia is often diagnostic and is less invasive than biopsy. These procedures are minimally invasive and effective for diagnosing pediatric hematologic malignancies.  相似文献   
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International medical education sessions have been successfully conducted by videoconferencing using Internet2. The sessions were between two tertiary care medical centres, in Honolulu and Bangkok. However, video quality was lower than for similar sessions using ISDN and audience satisfaction was less. The main reasons for the lower quality were network congestion and bandwidth allocation by the videoconferencing equipment. Software to ensure quality of service is available, but is not easy to implement. There were also network security problems and the costs were high. Our international videoconferences averaged 40-50 hours per year, an activity level at which connection costs were lower for ISDN than for Internet2. It appears that Internet2 videoconferencing for medical education is best reserved for academic institutions that have other high-bandwidth network requirements.  相似文献   
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Remote critical care consultations have been employed between the Naval Hospital in Guam and the Tripler Army Medical Center in Hawaii, a distance of 5300 km. During a 10-week study period there were physician-physician daily consultation rounds for patients in the intensive care unit at the Naval Hospital. Physiological data, video-images and sound were transmitted via a 768 kbit/s frame relay connection, albeit with a 1-3 s delay. During the study there were 87 consultations concerning 25 patients. Preliminary results showed that a broad range of critical care patients could be managed effectively through daily remote critical care consultation. Broader implementation of this strategy may represent a method of making critical care expertise available to front-line military health-care facilities and to remote civilian facilities with limited critical care expertise.  相似文献   
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Several novel brevetoxin derivatives were isolated and identified in Karenia brevis cultures and natural blooms by using solid phase extraction (SPE) and LC/MS(MS) techniques. These analogs were more polar compared with previously described brevetoxins, and were poorly extractable by conventional non-polar solvent (chloroform) partitioning. Brevetoxin analogs were structurally confirmed as hydrolyzed (open A-ring) forms of brevetoxins PbTx-1, PbTx-7, PbTx-2, and PbTx-3, and of oxidized PbTx-1 and PbTx-2. Some of these open A-ring derivatives were in greater abundance than their non-hydrolyzed counterparts. All were in much greater abundance in bloom water filtrate compared with cell-rich fractions. Open A-ring compounds were cytotoxic in mouse neuroblastoma (N2a) cell assay. In the K. brevis bloom-exposed Eastern oyster, brevetoxin metabolites with opened A rings were identified (e.g., open-ring cysteine-PbTx conjugates), contributing to their overall toxin burden.  相似文献   
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