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OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability. 相似文献
3.
C Demiroglu A Ozder T Altug B Orbay S Satar-Yíldírím A Bilir G Deniz T Erbengi S Büyükdevrim 《Angiology》1991,42(4):323-330
The effects of n-3 fatty-acid supplementation on serum lipids, platelet aggregation, and the development of atherosclerotic lesions were studied in the cholesterol-fed rabbit. Serum total cholesterol and LDL cholesterol values were significantly reduced in comparison with those of the nonsupplemented cholesterol-fed group (p less than 0.005, p less than 0.0025, respectively), though still higher than those of the control group (p less than 0.0025, p less than 0.0125 respectively). Platelet aggregation was reduced below that of the cholesterol-fed and the control levels (p less than 0.0005, p less than 0.0025, respectively). The endothelial injury encountered in cholesterol-fed rabbits was inhibited in the supplemented group. It is concluded that n-3 fatty acids suppress atherogenesis in this animal model by interfering with platelet aggregation and lipid metabolism. 相似文献
4.
Total serum IgE levels in a large cohort of patients with severe or difficult-to-treat asthma. 总被引:1,自引:0,他引:1
Larry Borish Bradley Chipps Yamo Deniz Sheila Gujrathi Beiyao Zheng Chantal M Dolan 《Annals of allergy, asthma & immunology》2005,95(3):247-253
BACKGROUND: Limited data are available on levels of IgE in large cohorts of patients with severe or difficult-to-treat asthma. OBJECTIVE: To examine IgE levels and disease in patients from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study. METHODS: From January 2001 to October 2001, 4,923 patients were screened for inclusion in the study. Of these, 4,756 patients 6 years or older with severe or difficult-to-treat asthma were enrolled and completed a baseline study visit. Total serum IgE levels were measured at the baseline visit and are summarized by geometric means. RESULTS: The mean total IgE level of the population is 106.6 IU/mL (95% confidence interval, 101.5-112.0 IU/mL). Children (6-12 years old) and adolescents (13-17 years old) have higher mean IgE levels than adults (> or =18 years old) (P < .001). Males have a higher mean IgE level than females (P < .001). IgE levels are higher among nonwhite patients than white patients (P < .001). Current smokers have higher IgE levels than past smokers or never smokers (P < .001). Among children, patients with severe asthma have a higher mean IgE level (280.2 IU/mL) than patients with moderate (145.8 IU/mL) or mild (137.8 IU/mL) asthma (P < .001). Among adults, patients with childhood-onset asthma have higher IgE levels (124.3 IU/mL [n = 1,348]) than patients with adult-onset asthma (65.7 IU/mL [n = 1,956]) (P < .001). CONCLUSION: In patients with severe or difficult-to-treat asthma from the TENOR study, higher total IgE levels were observed in males, children, smokers, nonwhite racial/ethnic groups, and adults with childhood-onset disease. In addition, IgE levels are associated with asthma severity among younger patients. 相似文献
5.
Gunel N Akcali Z Coskun U Akyol G Yamac D Yenidünya S 《Pathology, research and practice》2002,198(1):7-12
Tumor angiogenesis is believed to be related to prognostic factors involved in tumor development and metastasis. Using immunohistochemical methods, we evaluated tumor angiogenesis in 42 early invasive breast cancer patients (T1-2, NO-1-2, M0). Four patients received tamoxifen, 25 patients received CAF or CA, and 15 patients received CMF as adjuvant therapy. The median follow-up was 47 (range 24-119) months. Ten patients (43.5%) in the node-positive group and 2 patients (10.5%) in the node-negative group relapsed (p = 0.019). The mean microvessel count (MVC) was 60.3 3.05 per 200x field (range: 16-95). MVCs of postmenopausal and premenopausal patients were 50.13 +/- 5.74 and 68.64 +/- 4.11, respectively, in the axillary lymph node (ALN)-negative patient group (p = 0.04). Staining was moderate to strong in 13 (68%) ALN-negative and in 17 (74%) ALN-positive patients (p > 0.05), and was also moderate to strong in 82% of premenopausal patients and in 50% of postmenopausal patients (p = 0.037). There was no significant relationship between angiogenesis and p53, nor was angiogenesis significantly associated with the patient ER status and tumor size. No significant correlations were found between OS/DFS and Factor VIII staining or p53 (log rank test, p > 0.05). Of all ALN-negative patients with increased angiogenesis, one patient of the CMF group relapsed, but no recurrence occurred in patients undergoing anthracycline-based chemotherapy (p > 0.05). On the other hand, of all ALN-positive patients with increased angiogenesis, 5/14 patients treated with anthracylcine and 2/2 CMF-treated patients relapsed (p = 0.175). Despite the statistical insignificance, anthracycline-based adjuvant chemotherapy appears to be more effective than CMF as regards relapse prevention particularly in early ALN-positive breast cancer patients with increased angiogenesis. Additional studies are necessary to demonstrate the clinical importance of angiogenesis. 相似文献
6.
CD3- granulated leucocyte clones have been generated from human first-trimester decidualized endometrial tissue following culture in interleukin-2 (IL-2). Supernatants from both CD3- decidual granulated leucocyte (dGL) and CD3- peripheral blood natural killer (PBNK) cell clones inhibited the proliferation of choriocarcinoma cell lines. A panel of CD3- dGL clones, with or without phytohaemagglutinin stimulation, was assayed for cytokine secretion compared with CD3- PBNK clones and fresh tissue extracts. Levels of interferon-gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor-alpha (TNF-alpha) and IL-10 produced by stimulated CD3-CD8- dGL clones were greater than those produced by stimulated CD3-CD8+ dGL clones. In contrast, CD8+ dGL clones were more effective in production of IL-6 than CD8- dGL clones. Immunoreactive transforming growth factor-beta 2 (TGF-beta 2) was undetectable in supernatants from CD3- dGL and PBNK clones. CD3- dGL clones generally produced higher levels of all cytokines than PBNK clones. Some unstimulated CD3- dGL and PBNK clones spontaneously produced these cytokines, but usually at a reduced level. Fresh extracts of first-trimester decidual tissue contained detectable GM-CSF, TNF-alpha, IL-10,IL-6 and TGF-beta 2. Cytokine production by fresh CD3- dGL and CD3- dGL clones indicates that these cells could play an important role in the regulation of placental growth. 相似文献
7.
The in vivo existence of human NK cell subsets similar to Th1 and Th2 cells was demonstrated in freshly isolated IFN-gamma-secreting and IFN-gamma-nonsecreting NK cells. The IFN-gamma-secreting NK subset showed a typical cytokine pattern with predominant expression of IFN-gamma, but almost no IL-4, IL-5 and IL-13. In contrast, the IFN-gamma-nonsecreting NK subset was composed of IL-4, IL-5 and IL-13-producing NK cells. Short-time stimulation or 2 weeks of in vitro differentiation of NK cells led to distinct patterns of cytokine production similar to freshly-purified IFN-gamma (+) or IFN-gamma (-) NK cell subsets. NK cells stimulated with IL-12 produced increased levels of IFN-gamma and decreased levels of IL-4. In contrast, stimulation of NK cells with IL-4 inhibited IFN-gamma, but increased IL-13 production. Freshly-purified IFN-gamma (+) and IFN-gamma (-) or in vitro differentiated NK1 and NK2 subsets showed similar cytotoxicity to K562 cells. These results demonstrate that circulating NK cells retain effector subsets in humans with distinct cytokine profiles and may display different inflammatory properties. 相似文献
8.
Cadavers remain a principal teaching tool for anatomists and medical educators teaching gross anatomy. Infectious pathogens in cadavers that present particular risks include Mycobacterium tuberculosis, hepatitis B and C, the AIDS virus HIV, and prions that cause transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease (CJD) and Gerstmann-Straussler-Scheinker syndrome (GSS). It is often claimed that fixatives are effective in inactivation of these agents. Unfortunately cadavers, even though they are fixed, may still pose infection hazards to those who handle them. Specific safety precautions are necessary to avoid accidental disease transmission from cadavers before and during dissection and to decontaminate the local environment afterward. In this brief review, we describe the infectious pathogens that can be detected in cadavers and suggest safety guidelines for the protection of all who handle cadavers against infectious hazards. 相似文献
9.
Chemokine receptor CXCR4 expression in breast cancer as a potential predictive marker of isolated tumor cells in bone marrow 总被引:7,自引:3,他引:7
Cabioglu N Sahin A Doucet M Yavuz E Igci A O Yildirim E Aktas E Bilgic S Kiran B Deniz G Price JE 《Clinical & experimental metastasis》2005,22(1):39-46
Interactions between the CXCR4 chemokine receptor in breast cancer cells and the ligand CXCL12/SDF-1α are thought to play an important role in breast cancer metastases. In this pilot study, CXCR4 expression along with other biomarkers including HER2-neu and EGFR, were measured in primary tumor samples of patients with operable breast cancer to test whether any of these biomarkers alone and in combination could indicate breast cancer with high likelihood of metastasizing to bone marrow. Cytokeratin (CK) positive cells in bone marrow were identified by flow-cytometry following enrichment with CK 7/8 antibody-coupled magnetic beads. Primary tumors (n = 18) were stained with specific antibodies for CXCR4, HER2-neu, EGFR, and PCNA using an indirect avidin–biotin horseradish peroxidase method. The majority of the patients had T2/T3 tumors (72%), or lymph node involvement (67%) as pathologic characteristics that were more indicative of high-risk breast cancer. High CXCR4 cytoplasmic expression was found in 7 of 18 patients (39%), whereas 6 of 18 patients (33%) were found to have CK positivity in bone marrow. The median number of CK+ cells was 236 (range, 20–847) per 5 × 104 enriched BM cells. The presence of CK+ cells in bone marrow was found to be associated with increased expression of CXCR4 alone or in addition to EGFR and/or HER2-neu expression (P = 0.013, P = 0.005, and P = 0.025, respectively) in primary tumors. Furthermore, three patients with high CK positivity (>236 CK+ per 5 × 104 enriched bone marrow cells) in bone marrow exclusively expressed high levels of CXCR4 with EGFR/HER2-neu (P = 0.001). Our data suggest that high CXCR4 expression in breast cancer may be a potential marker in predicting isolated tumor cells in bone marrow. CXCR4 coexpression with EGFR/HER2-neu might further predict a particular subset of patients with high CK positivity in bone marrow. 相似文献
10.
Deniz Eyice Karabacak Semra Demir Osman Ozan Yeğit Ali Can Kadriye Terzioğlu Derya Ünal Müge Olgaç Raif Coşkun Bahauddin Çolakoğlu Suna Büyüköztürk Aslı Gelincik 《Allergy》2021,76(8):2535-2543