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961.
This study examined the measurement properties of a cognitive screening test, the Halifax Mental Status Scale (HMSS), in a population-based sample of community-living elderly subjects (N = 361) and a clinic sample (N = 20) of patients with Alzheimer's disease. Receiver operating characteristic analyses yielded estimates of sensitivity and specificity of approximately 90% for this test. Factor analysis confirmed a three-factor solution for the HMSS. Although both age and education were correlated with the HMSS total score, their relationship to the factor scores differed. Our study shows that comprehensive cognitive status tests do not measure a unitary construct and that adjustment of summary scores for education is unlikely to optimize sensitivity and specificity. In population-based studies, only those components of a test that reflect education should be adjusted.  相似文献   
962.
PURPOSE: The purpose of this study was to test interferon alfa (IFNalpha), 13-cis-retinoic acid (13cRA), and cisplatin biochemotherapy in advanced squamous cell carcinoma (SCC) of the skin. PATIENTS AND METHODS: Patients with advanced skin SCC received IFNalpha (5 x 10(6) IU/m(2), subcutaneous injection, three times a week), 13cRA (1 mg/kg, orally, daily), and cisplatin (20 mg/m(2), intravenous injection, weekly) in a phase II trial. The growth inhibition, cell-cycle, and apoptosis activity of these agents was evaluated in two skin SCC cell lines (SRB1-m7 and SRB12-p9). RESULTS: Thirty-nine patients were enrolled. All were assessable for survival, 35 for response and toxicity (median follow-up was 38 months). The overall and complete response rates were 34% and 17%, respectively, with median durations of 9 and 35.4 months, respectively. The response rate was higher in locally advanced (67%) than metastatic (17%) disease (P =.007). Median survival was 14.6 months. One-, 2-, and 5-year survival rate estimates were 58%, 32%, and 21%, respectively. Toxicity included generally mild to moderate fatigue and mucocutaneous dryness, moderate to severe neutropenia (38%), and neutropenic fever (6%). There were no treatment-related deaths. In vitro growth inhibition and apoptosis effects of cisplatin were differential and inversely associated with those of retinoic acid and especially IFNalpha in two skin SCC lines. CONCLUSION: The rising incidence, morbidity, and mortality of advanced skin SCC are a major challenge for clinical oncologists. Combined 13cRA, IFNalpha, and cisplatin was clinically active in extensive locally advanced disease. Each agent had independent, non-cross-resistant biologic effects in vitro, which may account for the combination's clinical activity.  相似文献   
963.
Opportunities for the detection, prediction, and treatment of breast cancer exist at three biological levels: systemically via the blood, at the whole organ level, and within the individual ductal lobular structures of the breast. This review covers the evaluation of approaches targeted to the ductal lobular units, where breast cancer begins. Studies to date suggest the presence of 5 to 12 independent ductal lobular systems per breast, each harboring complex cellular fluids contributed by local and systemic processes. New techniques for accessing and interrogating these systems offer the potential to gauge the microenvironment of the breast and distill biological risk profiles.  相似文献   
964.
BACKGROUND: Corynebacterium species are part of the normal skin flora. The incidence of nosocomial infections caused by Corynebacterium species have increased substantially over the past two decades. However, the clinical course of Corynebacterium peritonitis complicating peritoneal dialysis remains unclear. METHOD: We reviewed all the Corynebacterium peritonitis in our dialysis unit from 1995 to 2002. During this period, there were 1485 episodes of peritonitis recorded; 27 (1.8%) of which were caused by Corynebacterium species. RESULTS: The underlying renal diagnosis and prevalence of comorbid conditions of the 27 patients were similar to our whole dialysis population. The bacteria isolated were resistant to penicillin in 8 cases (29.6%). Three cases (11.1%) had concomitant exit-site infection. The overall primary response rate was 74.1%; the complete cure rate was 37.0%. Episodes that received vancomycin as initial antibiotic had a marginally higher primary response rate (9 in 10 vs 11 in 17 episodes, P = 0.2) and complete cure rates (7 in 10 vs 3 in 17 episodes, P = 0.12) than the episodes that received cephalosporins, although neither of the differences was statistically significant. Thirteen cases (48.1%) had recurrent peritonitis after antibiotic therapy, 8 of which had the recurrent episode at least 30 days after stopping antibiotics (median 54 days, range 43-60 days). Eight recurrent cases (61.5%) were successfully cured by another 3 week course of intra-peritoneal vancomycin. CONCLUSIONS: Recurrent Corynebacterium peritonitis is common after a 2 week course of antibiotics. Recurrent Corynebacterium peritonitis may be delayed up to 2 months after the antibiotic is stopped. Recurrent peritonitis can usually be cured with a 3 week course of intra-peritoneal vancomycin, which is probably the preferred antibiotic regimen for Corynebacterium peritonitis.  相似文献   
965.
Ebola virus RNA can reside for months or years in semen of survivors of Ebola virus disease and is probably associated with increased risk for cryptic sexual transmission of the virus. A modified protocol resulted in increased detection of Ebola virus RNA in semen and improved disease surveillance.  相似文献   
966.
967.
To evaluate the efficacy of intraperitoneal (IP) carboplatin-based therapy as salvage treatment of ovarian cancer, 46 patients with persistent or recurrent ovarian cancer following initial systemic chemotherapy were treated with a regimen of carboplatin (200-300 mg/m2) and etoposide (100 mg/m2) administered on a monthly schedule. A maximum of six courses of therapy was delivered, followed by a response laparotomy. The treatment program was well tolerated, except for bone marrow suppression, with one-quarter of patients developing platelet count depressions to < or = 50,000/mm3, and one-third experiencing hemoglobin levels of < or = 8 g/dl during treatment. Twelve (38%) of 32 patients evaluable for efficacy of the treatment program achieved a surgically documented response, including 8 (25%) complete responses. Of 25 patients whose largest tumor mass at the initiation of therapy measured < or = 0.5 cm, 11 (44%) responded, including 8 (32%) complete responses. We conclude that the IP administration of carboplatin can result in surgically documented responses when used in the salvage setting in patients with advanced ovarian cancer. The relative efficacy of carboplatin versus cisplatin when administered by the IP route to patients with ovarian cancer previously treated with platinum-based systemic therapy remains to be defined.  相似文献   
968.
We sought to describe tobramycin absorption after aerosol administration to cystic fibrosis (CF) subjects. Serum tobramycin concentrations were determined by modification of the radioimmuno-assay (RIA) technique, lowering the limit of detection from 1.0 &mgr;g ml(minus sign1) to 0.05 &mgr;g ml(minus sign1). In 37 studies, after aerosol delivery of 666 plus minus 195 mg to the airway of 24 patients, in which 222 samples were assayed, only 1 serum sample contained tobramycin at a concentration greater than 1.0 &mgr;g ml(minus sign1). Twenty-six of the 37 studies permitted estimation of pharmacokinetic parameters of tobramycin. The serum clearance of tobramycin following aerosol adminstration is 39.13 plus minus 0.393 L h(minus sign1) (mean plus minus standard error of the mean), with an elimination half-life of 3.072 plus minus 0.194 h. The half-life was significantly longer than that found after intravenous adminstration. The elimination rate constant (K(e)) was calculated to be 0.234 plus minus 0.002 h(minus sign1). Estimated total-body clearance in which systemic absorption was determined from sputum and urinary recovery of tobramycin was 0.094 plus minus 0.002 1 hr(minus sign1) kg(minus sign1). We also studied tobramycin absorption in six CF subjects after ingestion of a 80-mg m(minus sign2) dose, to gain insight into the tobramycin levels observed after swallowing an aerosol. Four out of the six subjects had measurable serum tobramycin concentration after ingestion. The serum concentration-time curve mirrored what was seen after aerosol administration. We concluded that tobramycin has poor systemic absorption in CF subjects after aerosol administration. Tobramycin in serum after aerosol administration is in part due to the gastrointestinal absorption of swallowed drug, as well as absorption from lower respiratory tract.  相似文献   
969.
970.
Summary The plasma pharmacokinetics of the antineoplastic anthracycline antibiotic aclacinomycin A (Acm) and its metabolites were studied in 12 patients treated with 60–120 mg/m2 during a phase I clinical trial. Total plasma drug fluorescence initially declined very rapidly, but from 2 to 24 h after injection, fluorescence rose progressively to intensities greater than those measured 1 min after Acm injection. Plasma total drug fluorescence slowly declined from 24 to 72 hours after Acm administration. These events reflected the rapid disappearance of Acm and the subsequent appearance of two highly fluorescent metabolites. One metabolite co-chromatographed with and had a fluorescence spectrum identical to known metabolite F1 (bisanhydroaklavinone). The other metabolite did not co-chromatograph with any previously described Acm metabolite. This metabolite had a fluorescence spectrum unlike any previously described Acm metabolite and was not altered by treatment for 60 min with 0.2N HCl at 100°C or by treatment for 24h at 37°C with bacterial -glucuronidase or limpet aryl sulfatase.Abbreviations used Acm aclacinomycin A - Dnr daunorubicin - Ard adriamycin - TLC thin layer chromatography - MLAB on-line modeling laboratory, Division of Computer Resources and Technology, National Institutes of Health - CxT concentration times time - Cp plasma concentration - t Time after administration of drug - Rf relative retardation factor - HPLC high performance liquid chromatography  相似文献   
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