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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.
OBJECTIVE: Hyperventilation and ischaemia increase axonal excitability by changing Na+ conductance in healthy subjects. However, the changes in excitability during and after ischaemia in diabetic patients are less than in healthy controls. This is known as ischaemic resistance. In this study, we investigated the effects of hyperventilation for 20 min on strength-duration time constant (SDTC) of motor axons of the median nerve of diabetic patients with polyneuropathy to determine whether diabetics are less affected by hyperventilation, a form of resistance similar to the ischaemic resistance of diabetics. METHODS: The SDTC of 14 diabetic patients with polyneuropathy and 10 healthy volunteers were measured following stimulation of right median nerve at the wrist prior to and after hyperventilation for 20 min. RESULTS: There was a significant increase in the SDTC in control subjects, but no significant change in the SDTC for patients with diabetic polyneuropathy. The score of the clinical response (paraesthesiae and carpopedal spasm) to hyperventilation of controls was also significantly greater in the controls than the patients. CONCLUSION: Hyperventilation for 20 min has little influence on SDTC in patients with diabetic polyneuropathy. SIGNIFICANCE: The 'resistance' of diabetic nerve is not confined to ischaemia but involves other manoeuvres that can alter axonal excitability. 相似文献
4.
Sajja Lokeswara Rao Mannam Gopichand Sompali Sriramulu Reddy Karri Venkata Ravirala Bala Raju Raju Bhupathiraju Soma Raju Penmetcha Krishnam 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(4):173-177
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass
has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried
out to compare mortality and morbidity in the off-pump and on-pump CABG groups.
Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG
and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for
bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL)
pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared.
Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG
with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12%
although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure
between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001).
Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in
both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in
off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and
hospital stay in OPCAB group. 相似文献
5.
Madhu Bala Harish Chandra Goel 《Journal of environmental pathology, toxicology and oncology》2004,23(2):139-144
Recent reports showed that whole extract of Podophyllum hexandrum was radioprotective in mice. Podophyllotoxin is one of the major constituents of the whole extract of Podophyllum. In this study we report on the radioprotective action of podophyllotoxin in Saccharomyces cerevisiae yeast. Proliferating yeast cells pretreated with podophyllotoxin (2.5-5.0 microg/mL) for > or =3 hours showed a higher surviving fraction after (60)Co-gamma-irradiation (200-600 Gy) than did the irradiated cells not pretreated with podophyllotoxin. The maximum increase (2.0 times) in surviving fraction was observed in cells treated with 2.5 microg/mL podophyllotoxin, 5 hours before (60)Co-gamma-irradiation (400 Gy). Podophyllotoxin was not mutagenic or recombinogenic at radioprotective doses (2.5 microg/mL). A post-irradiation decrease in revertants and gene convertants was observed in cells treated with podophyllotoxin (2.5 microg/mL podophyllotoxin, -5 hours, 400 Gy). This study indicates that podophyllotoxin is radioprotective in yeast, and its radioprotective effects in higher eukaryotes would be worth investigating. 相似文献
6.
Bala V. Manyam 《Epilepsia》1992,33(3):473-475
The ancient Indian medical system, Ayurveda, meaning science of life, is the oldest system of medicine in the world. Epilepsy is defined as Apasmara: apa, meaning negation or loss of; smara, meaning recollection or consciousness. Aura was recognized and was called Apasmara Poorva Roopa. A large number of symptoms indicative of aura were listed. Worthy of mention are subjective sensation of sounds, sensation of darkness, feeling of delusion, and dream-like state. An actual attack of Apasmara includes falling down; shaking of the hands, legs, and body; rolling up of the eyes; grinding of the teeth; and foaming at the mouth. Four major types of epilepsy based on the disturbance of doshas (humors) that govern the physiological and physiochemical activities of the body are mentioned. Apasmara is considered a dangerous disease that is chronic and difficult to treat. Several causes are mentioned. Treatment included correcting the etiological factors and dietary regimen and avoiding dangerous places that may result in injuries. 相似文献
7.
Six patients with prolonged acute courses of thrombotic microangiopathy are reviewed. These patients had in common courses of acute disease requiring plasma support for more than 3 months, with subsequent complete remission. Plasma support requirements may be prodigious, and the acute course may require more than 100 plasma exchanges before a stable remission is achieved. These patients appear to represent a subset of thrombotic microangiopathy distinct from the more common acute T.T.P. course, which resolves in 3–6 weeks, and the chronic relapsing pattern, which may have a short or prolonged acute course. © 1992 Wiley-Liss, Inc. 相似文献
8.
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
9.
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
10.
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