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排序方式: 共有1397条查询结果,搜索用时 15 毫秒
71.
In vivo and in vitro effects of stellate ganglion blockade on radial and internal mammary arteries 总被引:1,自引:0,他引:1
Dönmez A Tufan H Tutar N Araz C Sezgin A Karadeli E Torgay A 《Journal of cardiothoracic and vascular anesthesia》2005,19(6):729-733
OBJECTIVE: To investigate the effects of stellate ganglion blockade (SGB) on the internal mammary (IMA) and radial arteries (RA) in patients undergoing coronary artery bypass graft (CABG) surgery with in vivo and in vitro studies. DESIGN: Prospective, randomized trial. SETTING: University hospital. PARTICIPANTS: Thirty-seven patients undergoing CABG surgery. INTERVENTIONS: SGB was performed on 19 patients before anesthesia induction. Another group of 18 patients underwent surgery without SGB. Diameters of proximal RA, distal RA, and IMA were determined by Doppler ultrasonography before (T1) and after (T2) anesthesia induction. Control or blocked IMA and RA segments were obtained. Norepinephrine (NE) was applied to determine the contractile force of IMA and RA rings in a concentration-dependent manner. The maximal contractile response and the sensitivity of the vessels were compared. MEASUREMENTS AND MAIN RESULTS: The diameters of IMA and distal RA were statistically larger in the SGB group than those in the control group at T2. NE-induced maximum contraction was higher in the blocked RA rings than those in the control RA and blocked IMA rings. The sensitivity of IMA segments to NE was higher than that of RA segments in the SGB group. The control and blocked IMA segments showed similar sensitivity to NE. CONCLUSION: The present results show that SGB not only increases distal RA and IMA diameters but is also associated with in vitro differences, the mechanism of which remains to be elucidated. Therefore, SGB might be considered as an alternative to topical and systemic vasodilators for reducing vasospasm in patients undergoing CABG. 相似文献
72.
73.
Delibaş A Bek K Bülbül M Demircin G Baysun S Oner A 《Pediatric nephrology (Berlin, Germany)》2005,20(1):99-101
In nephrotic syndrome there is an increased tendency for bacterial infections due to immunological changes secondary to proteinuria, treatment (including steroids), and other as yet unknown causes. However, necrotizing fasciitis (NF) is an uncommon complication of the disease and has rarely been reported in nephrotic children. We report a 14-month-old boy with nephrotic syndrome who developed sepsis and NF as a complication. He was treated successfully with intensive medical and surgical treatment. 相似文献
74.
Gultekin B Ozkan S Uguz E Atalay H Akay T Arslan A Sezgin A Ozdemir N Tasdelen A Aslamaci S 《Artificial organs》2005,29(12):972-975
BACKGROUND: The life expectancy of patients with chronic renal failure who are dependent on dialysis is very poor. This study was undertaken to determine time-related outcomes in dialysis patients requiring cardiac valve replacement. METHODS: From 1994 to 2001, 29 end-stage renal disease (ESRD) patients on hemodialysis (HD) program underwent 30 valve replacement operations: 29 received mechanical valves (97%), and one received bioprosthetic valves. The sites of valve replacement were 11 aortic (36.7%), 18 mitral (60%), and one both aortic and mitral (3.3%). Mean age was 42.46 +/- 14.26 years (range 17-75 years). Follow-up was completed in 28 patients (96.5%). RESULTS: Early postoperative mortality (in the first 30 days) was 3.4% (n = 1). The overall estimated Kaplan-Meier survival was 56.7% at 36 months, 46.7% at 60 months, and 43.3% at 96 months. HD program was discontinued for two patients after renal transplantation in the follow-up period. All patients, except the one with bioprosthesis, used warfarin sodium for anticoagulation and none of them had bleeding. One of the patients had a major cerebrovascular accident (CVA) and another one had a minor CVA at the follow-up (6.7%). CONCLUSIONS: Life quality is better and life expectancy is longer after valve replacement in ESRD patients who have valvular disease. Also, longer life expectancy increases the probability for finding donors for kidney transplantation. 相似文献
75.
Surgical techniques that have been used during liver transplantation (LT) together with patient's coagulation profile and institutional practices are reported to have an effect on transfusion requirements. The aim of this study is to evaluate the transfusion requirement in both cadaveric (CDLT, n = 22) and living donor (LDLT, n = 24) pediatric LT performed in our institution. Balanced general anesthesia was used for all patients. Transfusion requirements were met to maintain a hemoglobin concentration of 8-10 g/dL, platelet level >50 x 10(3)/mL, prothrombin time <20 s and hemodynamic course with observing heart rate, arterial and central venous blood pressures and hourly urine output. Blood loss was replaced by using whole blood. Both groups' perioperative total blood and fresh-frozen plasma (FFP) volumes transfused, fluid requirements and hemodynamic courses, standard coagulation profile and metabolic variables determined in time periods of operations, patients' preoperative characteristics, operative features and postoperative events were compared. The mean transfusion requirements were 37.1 +/- 33.4 and 74.8 +/- 90.8 mL/kg of whole blood (p = 0.059) and 34.5 +/- 24.9 and 51.5 +/- 59.7 mL/kg of FFP for CDLT and LDLT, respectively (p = 0.519). The mean ages and mean body weights of the CDLT patients were higher than LDLT patients (9.7 +/- 5.3 vs. 6.6 +/- 4.4 yr, p = 0.015 and 32.4 +/- 17.7 vs. 21.0 +/- 14.8 kg, p = 0.032, respectively) while the mean operation time (493 +/- 135 vs. 323 +/- 93 min, p = 0.0001) and PELD score (13.1 +/- 11.2 vs. 20.1 +/- 11.8, p = 0.036) were higher for LDLT. In the entire population, multiple regression analysis showed that age, body weight and operation time have a significant combined effect on blood consumption (r2= 0.29, p = 0.003) meanwhile operation time was found to be an effective single variable (p = 0.002). None of the single or combined variables was found to have a significant effect on FFP consumption (r2= 0.17, p = 0.63) and crystalloid use (r2= 0.19, p = 0.11). Hemodynamic courses of both groups were similar. The incidences of metabolic acidosis and hypothermia during the anhepatic periods were higher in the CDLT group (p < 0.05). However, transfusion requirement in the ICU were higher in LDLT group [6.9 +/- 2.2 (n = 6) vs. 18.6 +/- 19 (n = 11) mL/kg, p < 0.05] after LT. As a result of this study in a pediatric patient population, no statistical significance was found in whole blood transfusion and FFP requirements between CDLT and LDLT. Duration of the operation was the primary factor effecting transfusion volume showing the importance of continued small volume losses during uncomplicated LT in this small sized patient population. Transfusion need for pediatric LT should be individualized for each patient based on the intraoperative conditions including surgical and patient features. 相似文献
76.
Uzüm G Akgün-Dar K Bahçekapili N Diler AS Ziylan YZ 《The International journal of neuroscience》2005,115(11):1503-1514
It has been known that susceptibility to some types of epilepsy is affected by sex. In addition, the role of NO in epileptogenesis is still unclear; NO has been suggested to be either an anticonvulsive or a proconvulsive agent. In an attempt to elucidate both the role of NO and sex differences in sensitivity to seizures, male and female Wistar rats were treated intraperitoneally (i.p.) by pentylentetrazol (PTZ)(80 mg/kg) and by a nitric oxide synthase(NOS) inhibitor N-omega-nitro-L-arginine-mthylester(L-NAME)(50mg/kg) and a NO precursor sodium-nitroprusside(SNP)(2.5mg/kg)- applied 15 min. before PTZ injection. Latency, frequency, severity, and duration of generalized clonic and clonic-tonic convulsions were recorded. Furthermore, alterations in severity, latency, frequency, and duration of convulsions were observed to correlate with NO. Both sexes, injected with PTZ, showed repetitive seizure patterns. Seizures were found to be more severe in females. L-NAME and SNP pretreatment produced paradoxical effects on PTZ-induced seizures in both sexes. L-NAME completely prevented PTZ-induced seizures in male rats, whereas increased severity, frequency, duration, and significantly shortened the latency in female rats. Unexpectedly, SNP increased convulsion severity, frequency, duration, and shortened latencies in male, whereas it decreased convulsion severity, frequency, and duration and prolonged latency in females. These results indicate that endogenous NO is involved in the regulation of convulsive action suggesting a role depending on sex. 相似文献
77.
Demirel F Ozer T Gürel A Acun C Ozdemir H Tomaç N Unalacak M 《Journal of pediatric endocrinology & metabolism : JPEM》2004,17(1):73-76
We evaluated goiter status and urinary iodine excretion (UIC) of 304 school-children (7-12 years old) 3 years after a law was passed for mandatory production of iodinated salt in an area previously characterized by severe iodine deficiency in Zonguldak, a mountainous city in the West Black Sea region in Turkey. We examined all the children for goiter by palpation, measured sonographic thyroid volumes (STV) and UIC. Eighty-two percent of families had been using iodinated salt. UIC was above 100 microg/l in 71.2% of the children and median UIC was sufficient (143.5 microg/l). The prevalence of goiter was lower at ultrasound (14.6%) than by palpation (19.4%). Median STV values were within recommended normal limits at all ages. Although Zonguldak had been a highly endemic region, it became mildly endemic 3 years after mandatory iodination of salt, with decrease of goiter prevalence. 相似文献
78.
Derman O Kanbur NO Tokur TE 《Journal of pediatric endocrinology & metabolism : JPEM》2004,17(8):1115-1119
We investigated the relationship between sex hormone binding globulin (SHBG) and pubertal gynecomastia in 21 adolescents evaluated longitudinally. Thirteen patients were given tamoxifen treatment after grading according to the Nydick classification (group 1). Group 2 consisted of eight patients followed without treatment. Gynecomastia existed bilaterally in 15 patients. There was a statistically significant breast size reduction in both groups. There was a significant decrease in serum SHBG only in group 2. These findings suggest that serum SHBG is increased by tamoxifen treatment in male adolescents. There was a decrease in SHBG levels through the duration of follow up in patients who recovered with or without treatment. However, this decrease was statistically significant in the untreated group, but not in the tamoxifen treated group. In conclusion, we suggest that the pubertal fall in SHBG levels is attenuated by tamoxifen treatment given for pubertal gynecomastia since tamoxifen increases SHBG levels in male adolescents. 相似文献
79.
This experiment was planned to answer the question of how the elimination of ipsilateral spermatogenetic material, which is necessary for contralateral testicular damage caused by an autoimmune response, affects contralateral testicular blood flow and fertility potential in unilateral spermatic cord torsion (USCT). Thirty-four male and 68 female adult albino rats were divided into three groups. Group 1 rats underwent a control operation, group 2 rats underwent subepididymal orchiectomy to eliminate spermatogenetic material, and group 3 rats underwent USCT after subepididymal orchiectomy. Testicular blood flows of the rats were measured by 133Xe clearance technique. Additionally, to determine fertility potential, each male rat was housed with two female rats. Numbers of impregnated and delivered rats were recorded. Both mean testicular blood flow and fecundity of group 3 were significantly lower than those of groups 1 and 2. When compared with groups 1 and 2, fertility and mean number of the impregnated rats of group 3 were lower but the differences were not significant. These findings suggest that absence of spermatogenetic material in USCT reduces contralateral blood flow and fertility potential. Therefore, contralateral testicular damage originating from blood flow alterations rather than autoimmune mechanism should be considered to explain fertility problems encountered following USCT. 相似文献
80.