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PURPOSE: To evaluate the role of adjuvant interferon alfa after complete resection of locally extensive renal cell carcinoma. PATIENTS AND METHODS: A total of 283 eligible patients with pT3-4a and/or node-positive disease were randomly assigned after radical nephrectomy and lymphadenectomy to observation or to interferon alfa-NL (Wellferon, Burroughs-Wellcome, Research Park, NC) given daily for 5 days every 3 weeks for up to 12 cycles. Patients were stratified on the basis of pathologic stage. Patients remained on treatment until documented recurrence, excessive toxicity, or patient/physician preference deemed removal appropriate. RESULTS: At median follow-up of 10.4 years, median survival was 7.4 years in the observation arm and 5.1 year in the treatment arm (log-rank P =.09). Median recurrence-free survival was 3.0 years in the observation arm and 2.2 years in the interferon arm (P =.33). Performance status (P =.003), nodal status (N2 v N0, P <.0001), and tumor stage (P =.0002) were significant prognostic factors in multivariate analysis. A proportional hazards model examining the effects of treatment arm and time to recurrence on survival after recurrence among patients who recurred found that random assignment to interferon treatment (P =.009) and shorter time to recurrence (P <.0001) were independent predictors of shorter survival after recurrence. Although no lethal toxicities were observed, severe (grade 4) toxicities including neutropenia, myalgia, fatigue, depression, and other neurologic toxicities occurred in 11.4% of those randomly assigned to interferon treatment. CONCLUSION: Adjuvant treatment with interferon did not contribute to survival or relapse-free survival in this group of patients.  相似文献   
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OBJECTIVES: Percentage of deliveries assisted by a skilled birth attendant (SBA) has become a proxy indicator for reducing maternal mortality in developing countries, but there is little data on SBA competence. Our objective was to evaluate the competence of health professionals who typically attend hospital and clinic-based births in Benin, Ecuador, Jamaica, and Rwanda. Methods: We measured competence against World Health Organization's (WHO) Integrated Management of Pregnancy and Childbirth guidelines. To evaluate knowledge, we used a 49-question multiple-choice test covering seven clinical areas. To evaluate skill, we had participants perform five different procedures on anatomical models. The 166 participants came from facilities at all levels of care in their respective countries. Results: On average, providers answered 55.8% of the knowledge questions correctly and performed 48.2% of the skills steps correctly. Scores differed somewhat by country, provider type, and subtopic. Conclusion: A wide gap exists between current evidence-based standards and current levels of provider competence.  相似文献   
5.
The purpose of this study was to determine the magnitude and clinical significance of surface measurement error in the determination of lumbar spinal flexion. Intrarater, inter-rater and intermethod reliability estimates were obtained using single inclinometry, double inclinometry and back range-of-motion inclinometry methods. Eight healthy subjects were examined independently by two experienced observers and three replicates of each measurement were obtained by each observer in a random sequence. In addition, three replicates of lumbar flexion angles were obtained for each subject by a single observer using the B-200. Reliability estimates were determined by intraclass correlation coefficients and were further compared by paired t tests between observation series. The median range of error was 8.5 degrees using the single inclinometer, 10.5 degrees using the double inclinometer and 16 degrees using the back range-of-motion. The intrarater reliability was generally higher than inter-rater reliability and intermethod reliability was low in most cases reflecting the poor cross-validity across inclinometry methods and between each inclinometry method and the B-200. In conclusion, significant measurement error in estimating lumbar flexion by inclinometry may be expected to occur even in a "controlled" setting using experienced observers, standard examination techniques and asymptomatic healthy subjects. These findings appear to undermine the expectation that the clinician can reliably apply surface inclinometry to estimate loss of spinal mobility for purposes of impairment determination.  相似文献   
6.
The rapid detection of fungemia in hospitalized patients is imperative, particularly for those who are immunocompromised. Our laboratory compared the Roche Septi-Chek with the Du Pont Isolator for the recovery of fungi from blood. Of 23,586 matched pairs of blood cultures, 199 were positive. The Isolator detected 178 (89.4%) and the Septi-Chek detected 119 (59.7%) of all positive isolates. The mean recovery time for the Isolator and Septi-Chek was 2.2 and 4.9 days, respectively. The Isolator detected fungemia earlier than the Septi-Chek did and was the only culture system positive in 83% of 53 patients, whereas the Septi-Chek system yielded the same results in only 13% of the patients. The Isolator provides a more rapid and sensitive method for the recovery of fungi from blood.  相似文献   
7.
The authors investigated assays for free protein S (ProS) antigen, total ProS antigen, and ProS crossed immunoelectrophoresis (CIEP) in the diagnosis of type 1 inherited ProS deficiency. Accurate measurement of the hemostatically important free ProS required showing that, on each specimen, precipitation of the C4b-binding protein (C4b-BP)/protein S complex (C4b-BP/ProS) by polyethylene glycol-8,000 (PEG) was complete. The authors showed this by doing a ProS CIEP on the same PEG supernate that was used for quantitative measurement of free ProS. The +/- 2 standard deviation (+/- 2 SD) ranges for free ProS were 81-133% for males and 50-130% for females. This striking male-female difference has been reported only twice before. With the use of a graph of values for free ProS versus prothrombin time (PT), patients with inherited ProS deficiency segregated cleanly from normals and from patients on warfarin therapy without ProS deficiency until the PT was greater than 20 seconds. There is overlap of total ProS antigen values between normals and patients with inherited ProS deficiency.  相似文献   
8.
Twelve new B*15 alleles are described. All of the known B*15 alleles are divided into subgroups based on serologic assignments and/or nucleotide sequence polymorphisms. These groups might be used as a reference for DNA-based testing at an intermediate (i.e. "serologic") level of resolution.  相似文献   
9.
The proximal region of the superficial digital flexor tendon of pigs passes under the tibiotarsal joint, where it is subjected to compressional and tensional forces. This region was divided into a surface portion (sp), which is in direct contact with the bone and into a deep portion (dp), which is the layer opposite the articulating surface. The purpose of this work was to analyse the distribution and organisation of the collagen bundles and proteoglycans in the extracellular matrix in sp and dp. Toluidine‐blue‐stained sections were analysed under a polarising microscope. Strong basophilia and metachromasia were observed in sp, demonstrating accumulation of proteoglycan in a region bearing compression, but the intensity was reduced the further layers were from the bone. Linear dichroism confirmed that the glycosaminoglycan molecules were disposed predominantly parallel to the longest axis of the collagen fibrils. Birefringence analysis showed a higher molecular order and aggregation of the collagen bundles in areas where the tension was more prominent. The crimp pattern was more regular in dp than in sp, probably as a requirement for tendon stretching. The optical anisotropy exhibited by the collagen bundles also confirmed the helical organisation of the collagen bundles in the tendon. Hyaluronidase digestion caused a decrease in the basophilia, but this was not eliminated, supporting the idea that in the matrix, proteoglycans are not completely available to the enzyme action.  相似文献   
10.
Eosinophils are an important source of leukotriene (LT)C(4), which can be synthesized within lipid bodies-cytoplasmic organelles where eicosanoid formation may take place. Allergy-driven lipid body formation and function have never been investigated. Here, we studied the in vivo induction and role of lipid bodies within eosinophils recruited to sites of allergic inflammation. Using two murine models of allergic inflammation (asthma and pleurisy), we verified that parallel to the eosinophil influx, allergic challenge also induced lipid body formation within recruited eosinophils. Neutralizing antibodies to eotaxin/CCL11, RANTES/CCL5, or CCR3 partially inhibited lipid body formation within recruited eosinophils in the allergic pleurisy model. Likewise, intrapleural administration of RANTES or eotaxin also induced significant influx of eosinophils loaded with lipid bodies. By immunolabeling, we detected the presence of a key enzyme involved in the leukotriene metabolism-5-lipoxygenase-within eosinophil lipid bodies formed in vivo after allergen challenge. Furthermore, specific immunolocalization of newly formed LTC(4) demonstrated that lipid bodies were the sites of formation of this eicosanoid within infiltrating eosinophils. Therefore, allergic inflammation triggers in vivo formation of new lipid bodies within infiltrating eosinophils, a phenomenon largely mediated by eotaxin/RANTES acting via CCR3 receptors. Such in vivo allergen-driven lipid bodies function as intracellular compartments of LTC(4) synthesis.  相似文献   
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