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991.
SS Kroll GP Reece MJ Miller GR Evans GL Robb BJ Baldwin BG Wang MA Schusterman 《Canadian Metallurgical Quarterly》1997,99(6):1602-1605
This study compared nipple projection after nipple reconstruction (following breast mound reconstruction) with either the modified double-opposing tab flap or the star flap. Areolar reconstruction and pigmentation of the nipple were achieved with tattooing. Nipple projection for 153 nipples was measured at least 6 months after the reconstruction, when projection was believed to have become stable. Mean follow-up was 2.27 years. In the 106 nipples reconstructed with modified double-opposing tab flaps, the mean projection was 2.4292 mm, while in the 47 nipples reconstructed with star flaps, the mean projection was 1.9681 mm (p = 0.021). We conclude that although both methods are effective, the modified double-opposing tab flap has slightly more projection after approximately 2 years. It is not known, however, whether this is because of reduced flap atrophy or longer initial projection by the modified double-opposing tab flap; further studies are ongoing. 相似文献
992.
993.
E Righi G Rossi G Ferrari A Dotti C De Gaetani P Ferrari GP Trentini 《Canadian Metallurgical Quarterly》1997,17(6):436-439
The frequent change of the transitional cell carcinoma of the urinary tract accounts for the fact that cytological abnormalities in urinary specimens are often not sufficient to enable a definitive diagnosis of malignancy. The purpose of this work was to evaluate the possible use of p53 protein in increasing the diagnostic accuracy of urinary cytology. The expression of p53 was investigated by immunocytochemistry in two groups of urinary specimens, one cytologically positive and the other cytologically negative for cancer. Immunostaining was carried out using a monoclonal antibody to p53. In the positive group, in which bladder cancer was confirmed by cystoscopy and biopsy (31 cases), positive reaction for p53 was found in 55% of the cases (17 cases). In the negative group (92 cases), presence of cancer was histologically ascertained in 64 cases and in this group 15 cases (23.4%) showed positive p53 staining. In the remaining 28 cases of this group, where TCC was not present, 7 cases showed p53 positivity in non-neoplastic urothelial cells. This result shows that, while immunocytochemical detection of p53 in urinary specimens may be used for prognostic evaluation of patients with bladder cancer, it does not contribute to the diagnostic accuracy in cases with morphologically inconclusive or negative cytology. The sensitivity and specificity of the method in detecting bladder carcinoma were 23.5 and 75%, respectively. 相似文献
994.
OBJECTIVE: To describe the pattern of inpatient hospital utilization, up to 15 years after injury, among a cohort of veterans with service-connected traumatic spinal cord injury (SCI). PATIENTS: A cohort of 1,250 male veterans, with traumatic SCI occurring between 1970 and 1986, who visited the VA within 1 year of injury, was assembled from VA administrative files; diagnosis was verified by examining hospital discharge summaries. DESIGN: Computerized record linkage among Department of Veterans Affairs (VA) administrative files was used to determine patterns of inpatient hospital utilization. MAIN OUTCOME MEASURE: Pattern of inpatient admissions and length of stay (LOS). RESULTS: Patients were typically white males injured in their mid-twenties. The initial VA hospitalization began approximately 6 weeks after injury and lasted 4 to 7 months, depending on injury level and completeness. Subsequent hospitalizations usually lasted approximately 10 days, but 22% of stays exceeded 1 months. Most hospitalizations took place in specialized SCI Centers. Comparing the 1980s with the 1970s, patients in the 1980s entered VA facilities sooner after injury, were more likely to visit SCI Centers, and had shorter initial stays. Rates for the incidence of rehospitalization decreased rapidly in years 2-5 after injury and declined less rapidly thereafter. Occupancy rates and proportion rehospitalized followed similar patterns. The incidence rate for persons with complete quadriplegia was approximately twice that of patients with incomplete paraplegia. Between 1970 and 1991, both the rehospitalization incidence rate and LOS decreased by approximately 20%. Only 10% of patients accounted for 46% of the total LOS. LOS during the first five years was predictive of later LOS. CONCLUSIONS: The pattern of rehospitalization in VA facilities was generally consistent with that of the Model Systems. Efforts toward preventing rehospitalization should target persons with previous high utilization. 相似文献
995.
996.
Systematic reviews are becoming prominent tools to guide health care decisions. As the number of published systematic reviews increases, it is common to find more than 1 systematic review addressing the same or a very similar therapeutic question. Despite the promise for systematic reviews to resolve conflicting results of primary studies, conflicts among reviews are now emerging. Such conflicts produce difficulties for decision-makers (including clinicians, policy-makers, researchers and patients) who rely on these reviews to help them make choices among alternative interventions when experts and the results of trials disagree. The authors provide an adjunct decision tool--a decision algorithm--to help decision-makers select from among discordant reviews. 相似文献
997.
An expression-cloning strategy was used to isolate a cDNA that encodes a protein that confers calcitonin gene-related peptide (CGRP) responsiveness to Xenopus laevis oocytes. A guinea pig organ of Corti (the mammalian hearing organ) cDNA library was screened by using an assay based on the cystic fibrosis transmembrane conductance regulator (CFTR). The CFTR is a chloride channel that is activated upon phosphorylation; this channel activity was used as a sensor for CGRP-induced activation of intracellular kinases. A cDNA library from guinea pig organ of Corti was screened by using this oocyte-CFTR assay. A cDNA was identified that contained an open reading frame coding for a small hydrophilic protein that is presumed to be either a CGRP receptor or a component of a CGRP receptor complex. This CGRP receptor component protein confers CGRP-specific activation to the CFTR assay, as no activation was detected upon application of calcitonin, amylin, neuropeptide Y, vasoactive intestinal peptide, or beta-endorphin. In situ hybridization demonstrated that the CGRP receptor component protein is expressed in outer hair cells of the organ of Corti and is colocalized with CGRP-containing efferent nerve terminals. 相似文献
998.
T Baardman WT Hermens T Lenderink GP Molhoek G Grollier M Pfisterer ML Simoons 《Canadian Metallurgical Quarterly》1996,17(2):237-246
BACKGROUND: The recent international GUSTO trial of 41,021 patients with acute myocardial infarction demonstrated improved 90-min infarct related artery patency as well as reduced mortality in patients treated with an accelerated regimen of tissue plasminogen activator, compared to patients treated with streptokinase. A regimen combining tissue plasminogen activator and streptokinase yielded intermediate results. The present study investigated the effects of treatment on infarct size and enzyme release kinetics in a subgroup of these patients. METHODS: A total of 553 patients from 15 hospitals were enrolled in the study. Four thrombolytic strategies were compared: streptokinase with subcutaneous heparin, streptokinase with intravenous (i.v.) heparin, tissue plasminogen activator with i.v. heparin, and streptokinase plus tissue plasminogen activator with i.v. heparin. The activity of alpha-hydroxybutyrate dehydrogenase (HBDH) in plasma was centrally analysed and infarct size was defined as cumulative HBDH release per litre of plasma within 72 h of the first symptoms (Q(72)). Patency of the infarct-related vessel was determined by angiography in 159 patients, 90 min after treatment. RESULTS: Infarct size was 3.72 g-eq.1(-1) in patients with adequate coronary perfusion (TIMI-3) at the 90 min angiogram and larger in patients with TIMI-2 (4.35 g-eq.1(-1) or TIMI 0-1 (5.07 g-eq.1(-1) flow (P = 0.024). In this subset of the GUSTO angiographic study, early coronary patency rates (TIMI 2 + 3) were similar in the two streptokinase groups (53 and 46%). Higher, but similar, patency rates were observed in the tissue plasminogen activator and combination therapy groups (87 and 90%). Median infarct size for the four treatment groups, expressed in gram-equivalents (g-eq) of myocardium, was 4.4, 4.5, 3.9 and 3.9 g-eq per litre of plasma (P = 0.04 for streptokinase vs tissue plasminogen activator). Six hours after the first symptoms, respectively 5.3, 6.6, 14.0 and 13.6% of total HBDH release was complete (P < 0.0001 for streptokinase vs tissue plasminogen activator). CONCLUSIONS: Rapid and complete coronary reperfusion salvages myocardial tissue, resulting in limitation of infarct size and accelerated release of proteins from the myocardium. Treatment with tissue plasminogen activator, resulting in earlier reperfusion was more effective in reducing infarct size than the streptokinase regimens, which contributes to the differences in survival between treatment groups in the GUSTO trial. 相似文献
999.
GP Oakley 《Canadian Metallurgical Quarterly》1997,11(4):579-581
The major known environmental causes of birth defects are ancient agents that have been in the environment for centuries but have been only recently discovered-rubella, alcohol, and folic acid deficiency. In the United States, we have made great progress in preventing congenital rubella syndrome. We also have a great opportunity to prevent spina bifida and anencephaly (SBA) by increasing the number of women who daily consume vitamin supplements containing folic acid. Even with the recently announced grain fortification regulations, there are 45 million women unprotected from an SBA-affected pregnancy. This article suggests that a substantial educational campaign could, over a 5-year period, double the number of women consuming folic acid supplement pills and make a substantial contribution toward preventing SBA. 相似文献
1000.
G Christie A Barton B Bolognese DR Buckle RM Cook MJ Hansbury GP Harper LA Marshall ME McCord K Moulder PR Murdock SM Seal VM Spackman BJ Weston RJ Mayer 《Canadian Metallurgical Quarterly》1997,27(12):3228-3235
CD23, the low-affinity IgE receptor, is up-regulated on interleukin (IL)-4-stimulated B cells and monocytes, with a concomitant increase in the release of soluble fragments of CD23 (sCD23) into the medium by proteolytic processing of the surface-bound intact CD23. The effect of inhibition of the processing of CD23 on IgE production in human and mouse cells and in a mouse model in vivo was evaluated. CD23 processing to sCD23 from RPMI 8866 (a human Epstein-Barr virus-transformed B cell line) cell membranes was inhibited by a broad-spectrum matrix-metalloprotease inhibitor, batimastat, with an IC50 of 0.15 microM. Batimastat also inhibited CD23 processing in whole RPMI 8866 cells as well as in IL-4-stimulated purified human monocytes with similar IC50. Batimastat inhibited IgE production from IL-4/anti-CD40-stimulated human tonsil B cells as well as mouse splenic B cells in a manner consistent with inhibition of CD23 processing. Release of soluble fragments of CD23 in the cell supernatants of tonsil B cells was inhibited over the concentration range of 1-10 microM batimastat and intact cell surface CD23 was increased on mouse splenic B cells in the presence of these concentrations of batimastat. IgE production of IL-4-stimulated human peripheral blood mononuclear cells was also blocked by 1-10 microM batimastat, again with comparable inhibition of sCD23 release over the same concentration range. Finally, in a mouse model of IgE production, batimastat inhibited IgE production in response to ovalbumin challenge as determined by serum IgE levels. Taken together, the data support a role of CD23 in IgE production and point to CD23 processing to sCD23 as a therapeutically relevant control point in the regulation of IgE synthesis. 相似文献