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991.
William R Colyer Christopher J Cooper Mark W Burket William J Thomas 《Catheterization and cardiovascular interventions》2003,59(3):372-377
Renal ischemia due to renal artery stenosis (RAS) is an important cause of secondary hypertension and renal insufficiency. Several methods are available to diagnose RAS; however, the identification of clinically significant lesions remains problematic. We measured the translesional systolic pressure gradient (TSPG) with a 4 Fr catheter and a 0.014" pressure-sensing guidewire and compared these data to angiographic findings. The TSPG obtained by pressure-sensing guidewire correlated more strongly with angiographic minimal lumen diameter (r(2) = 0.801) than those obtained by 4 Fr catheter (r(2) = 0.360). The relationship of TSPG with percent stenosis was not strong, regardless of the method used (r(2) = 0.228 with pressure-sensing guidewire, 0.358 with 4 Fr catheter). Using a 0.014" pressure-sensing guidewire is effective for assessing TSPG and provides a more reliable indication of stenosis significance than use of a 4 Fr catheter. 相似文献
992.
Ke MS Kamath NV Nihal M Mikkola DL Koc ON Stevens SR Gilliam AC Cooper KD Wood GS 《Journal of the American Academy of Dermatology》2003,48(2):238-243
BACKGROUND: Folliculotropic mycosis fungoides (MF) is a rare variant of cutaneous T-cell lymphoma, MF type, characterized by atypical lymphocytes preferentially infiltrating the hair-follicle epithelium relative to the epidermis. OBSERVATIONS: We describe a rare case of folliculotropic MF involving the central nervous system. This is also the first case in which laser capture microdissection was used to show that the atypical lymphocytes within the hair-follicle epithelium were part of the same tumor clone present in other tissue compartments. CONCLUSIONS: In reviewing the literature describing atypical lymphocytes infiltrating hair-follicle epithelium relative to the epidermis, we encourage the use of the term folliculotropic mycosis fungoides. Our case also supports previous findings that central nervous system involvement can occur in advanced MF. The successful procurement and analysis of atypical lymphocytes from hair-follicle epithelium by laser capture microscopy ushers in a new era in molecular diagnostics. 相似文献
993.
Photo-damage of the head and neck was assessed, by visual inspection, in 82 Northern European renal transplant recipients attending a dermatology clinic. Photo-damage was graded as absent, mild, moderate and severe and the presence or absence of skin telangiectasia, solar elastosis, erythema and pigmentation was assessed. The duration and type of immunosuppressant and calcium channel blocker medication was recorded. Ninety percent had photo-damaged skin with 41 (50%) having mild photo-damage, 20 (24%) moderate photo-damage and 13 (16%) severe photo-damage. Sixty-two (76%) had pigmentation, 43 (52%) telangiectasia, 65 (79%) papular changes and 51 (65%) erythema. Fifty-three patients (65%) had received a calcium channel blocker (49 nifedipine, four amlodipine). The grade of photo-damage was strongly associated with use of calcium channel blockers (P=0.001) as was the presence of telangiectasia (P=0.001) and solar elastosis (P=0.04). Photo-damage is frequent in this population of renal transplant patients. Telangiectasia in association with calcium channel blockers has been reported rarely but appears to be common in the transplant population. 相似文献
994.
Coronary artery aneurysms are uncommon and may be complicated by rupture, thromboembolic phenomenon, and more rarely fistulation into one of the cardiac chambers. This case report highlights the difficulty in making a preoperative diagnosis of a coronary artery aneurysm that has fistulated into the right atrium, and lists possible differential diagnoses. 相似文献
995.
The relationship between iron status and atherosclerosis has long been a topic of debate in the literature. Despite more than 25 years of research, there is no consensus regarding a causal relationship. To date, the vast majority of studies have focused on iron burden with respect to a hypothesized role in the onset and progression of coronary artery disease. However, the effect of iron in the coronary arterial system may differ mechanistically and therefore clinically from its effect in the peripheral arterial system. This review will summarize the biochemical, pathologic, animal, and clinical research data with respect to iron and atherosclerosis. This background will be expanded upon to provide insights into ongoing studies and paths for future investigations into the role of iron and peripheral arterial disease. 相似文献
996.
Resiniferatoxin-induced loss of plasma membrane in vanilloid receptor expressing cells 总被引:3,自引:0,他引:3
Caudle RM Karai L Mena N Cooper BY Mannes AJ Perez FM Iadarola MJ Olah Z 《Neurotoxicology》2003,24(6):895-908
Resiniferatoxin (RTX), a potent analog of capsaicin, was evaluated electrophysiologically in dorsal root ganglion (DRG) cells and cell lines ectopically expressing the vanilloid receptor type 1 (VR1) to determine if cell phenotype influenced RTXs neurotoxic properties. Furthermore, capsaicin and heat activation of VR1 were evaluated in these cells to determine if cellular damage was unique to RTX activation of the receptors. RTX application to DRG cells identified as type 1, 2 or 5, cell types known to express VR1, induced large inward currents. RTX did not induce currents in DRG cells that do not express the receptor (type 4 cells). In cell lines ectopically expressing VR1, RTX-induced similar currents. RTX produced no effect in non-transfected cells. After exposure to RTX both DRG cells and transfected cells failed to respond to subsequent applications of the agonist. In addition, whole cell capacitance was reduced up to 70%. The decrease in capacitance was associated with the loss of plasma membrane, as determined by confocal microscopy. Cell phenotype, other than VR1 expression, did not influence the response to RTX. Interestingly, capsaicin and heat activation of vanilloid receptors also decreased cell capacitance, but the loss of membrane was not as great as with RTX and responses to these stimuli were not lost after the initial exposure. The loss of cell membrane required elevated intracellular levels of Ca2+. From these data it was concluded that the loss of cell membrane was dependent on the presence of both VR1 and intracellular Ca2+ accumulation, but not on cell phenotype. 相似文献
997.
We hypothesized that a prior history of a major depressive disorder would not compromise the efficacy of percutaneous transluminal coronary angioplasty (PTCA), a coronary revascularization procedure, in improving quality of life and health status when comparing patients with no previous history. To determine the utility of screening for risk for depression in heart patients scheduled for PTCA, 190 patients were administered a two-item depressive disorders screener prior to PTCA and the SF-36 and Seattle Angina Questionnaire prior to and 6 months post procedure. Results reveal that while those with no prior history of depression had statistically better quality of life and health status outcomes than those with a probable past depression, (P <.05), the clinically meaningful differences as determined by effect size scores showed that those susceptible to recurrent depression benefited from PTCA as well as, and on some measures better than those with no previous history. Prescreening patients at probable risk for a depression is not a valid or helpful enterprise if the purpose is to develop intervention strategies for improving outcome post PTCA. Screening out patients based on history of depression may in fact lead to an inequitable allocation of resources and have no major benefit in enhancing quality of life and improving health status. 相似文献
998.
Battafarano RJ Piccirillo JF Meyers BF Hsu HS Guthrie TJ Cooper JD Patterson GA 《The Journal of thoracic and cardiovascular surgery》2002,123(2):280-287
OBJECTIVE: As the mean age in patients with non-small cell lung cancer increases, the proportion of patients with serious comorbidity who are considered for surgical resection also increases. Patients with non-small cell lung cancer have been shown to have a higher burden of comorbidity than do patients with tumors of other sites, such as breast, prostate, colon, and head and neck. The goal of this review was to determine the impact of comorbidity on postoperative and long-term survival after surgical resection in patients with stage I non-small cell lung cancer. METHODS: A database analysis of our hospital's tumor registry included 451 patients who underwent surgical resection for pathologic stage I non-small cell lung cancer between January 1, 1994, and December 31, 1999. Comorbidity severity was prospectively determined with the Kaplan-Feinstein Index. Survival data were collected for each patient from the date of operation, with a mean duration of follow-up of 35.7 months. Bivariate statistics and Cox proportional hazards model analyses were used. RESULTS: The mean age was 64.4 years, and 249 (55%) patients were male. The distribution of overall comorbidity severity was none, 142 (31.5%); mild, 150 (33.3%); moderate, 115 (25.5%); and severe, 44 (9.8%). The overall in-hospital mortality was 2.2% (n = 10/451). There was a nonsignificant trend toward higher hospital mortality with greater comorbidity: none, 0.7% (n = 1/142); mild, 3.3% (n = 5/150); moderate, 0.9% (n = 1/115); and severe, 6.8% (n = 3/44, P =.055). Kaplan-Meier estimated survivals at 3 years for each level of comorbidity were as follows: none, 85.6%; mild, 74.8%; moderate, 68.8%; and severe, 70.0% (P <.002). After adjustment for age, sex, T status, and tumor histologic type, the relative risks of death as a function of comorbidity were mild, 1.44 (95% confidence interval 0.89-2.34); moderate, 2.28 (95% confidence interval 1.43-3.65); and severe; 1.94 (95% confidence interval 1.023-3.70). CONCLUSIONS: Comorbidity has a significant impact on survival after surgical resection of patients with stage I non-small cell lung cancer. These data may help to explain the lower than expected survival results for patients after surgical resection for stage I non-small cell lung cancer. 相似文献
999.
PURPOSE: We designed a survey to assess the microwave sterilization technique practiced by patients at our clinic who perform clean intermittent catheterization. MATERIALS AND METHODS: A 23-question survey addressing urinary catheter use and home sterilization techniques was mailed to 129 patients. A followup survey was mailed to 47 respondents who reported using a microwave oven to sterilize the catheters to assess the microwave technique further. RESULTS: Of the 129 initial surveys 84 (64%) were returned, while 40 (85%) of the 47 followup questionnaires on microwave sterilization were returned. All patients surveyed have used clean intermittent catheterization for at least 1 year and 75% have used it more than 5 years. Of the respondents 80% perform clean intermittent catheterization 4 to 5 times daily, although sterilization frequency varies from daily to less than once weekly. Of the respondents 71% reported no difficulty with microwave sterilization, although 31 (63%) reported a history of catheter melting during microwaving. Of the respondents 35% reported using a rotation table, all used a heat sink containing 1/2 to 4 cups of water, 39% used 500 to 1,000 W., 37% used greater than 1,000 W., 73% set the microwave for 6 minutes, others set it for 3 to 30 minutes and 98% used a power setting described as high, full, 10 or 100%. CONCLUSIONS: Significant variation exists in the cleaning and sterilizing techniques used by our patients, although they were given uniform written and verbal instructions. It is unclear from the data in the literature how this variation affects sterilization. 相似文献
1000.
Bühler L Kurilla-Mahon B Chang Q Abraham S Alwayn IP Appel JZ Newman D Awwad M White-Scharf ME Sackstein R Sachs DH Cooper DK Down JD 《Transplantation》2002,74(8):1159-1166
BACKGROUND: The aim of the present study was to determine whether certain components of nonmyeloablative regimens for hematopoietic cell transplantation might compromise the growth of hematopoietic progenitors. METHODS: Porcine peripheral blood progenitor cells (PBPC) were cytokine-mobilized, collected by leukapheresis, and cryopreserved using 5% dimethyl sulfoxide and 6% hydroxyethyl starch. The influence of cryopreservation on PBPC was tested in vitro by enumeration of colony-forming units (CFUs) in methylcellulose and cobblestone area-forming cell (CAFC) subsets in stromal-associated long-term cultures on fresh and frozen PBPC. The effects of mycophenolate mofetil (MMF) on porcine PBPC and baboon and human bone marrow (BM) were tested in vitro by adding varying doses of MMF to the CFU assays. One baboon was treated with increasing doses of MMF (100-500 mg/kg per day continuously intravenous), and sequential BM aspirations were tested for CFU content. RESULTS: Fresh cytokine-mobilized PBPC had similar frequencies of progenitor cells when compared with porcine BM. Freezing-thawing of PBPC had no effect on porcine CFUs but reduced the recovery of CAFCs by more than 90%. In vitro, MMF completely inhibited the development of porcine and human CFUs at a concentration of 1 microg/mL and of baboon CFUs at levels between 10 and 100 microg/mL. Plasma-free mycophenolic acid levels of 10 to 30 microg/mL were associated with decreased CFUs in the BM. CONCLUSIONS: Cryopreservation and MMF potentially prevent engraftment of porcine PBPC by reducing the content or development of progenitor cells. These results indicate that the use of fresh PBPC might improve the induction of mixed hematopoietic chimerism and raise the possibility that use of high doses of MMF in the poststem cell transplant may compromise engraftment. 相似文献