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排序方式: 共有210条查询结果,搜索用时 62 毫秒
1.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生. 相似文献
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The aim of the present study was to examine whether ischaemic episodes of less than 5 min could induce preconditioning or stunning in the isolated rat heart. Hearts were subjected to total global ischaemia of 1, 2 and 4 min followed by 10 min of reperfusion before an 18-min main ischaemic period and 30 min of reperfusion. The effects on physiology, purine metabolism and anaerobic glycolysis were compared with a control group subjected to the main ischaemia only. The brief ischaemic episodes did not produce stunning based on the recovery of left ventricular developed pressure (LVDP) and heart rate (HR) product during the first reperfusion. Preconditioning of 11–14% increased recovery of LVDP x HR during the second reperfusion was observed in the 1- and 4-min group. In the 2-min group a low repayment of flow debt during the first reperfusion was associated with a slightly reduced recovery of LVDP x HR compared to the other preconditioned groups during the second reperfusion. Only in the 4-min group was preconditioning associated with fewer breakdown products of the purine nucleotide pool (adenosine) and anaerobic glycolysis (lactate) in both tissue and effluate after the main ischaemia. Preconditioning (reflected in recovery of function) could be produced with ischaemic episodes of less than 5 min that did not produce stunning. Thus, stunning is probably not the primary cause of preconditioning. 相似文献
4.
STUDY DESIGN: A retrospective review of 244 adult spine instrumentation and fusion surgery cases (1994-1995) from one institution. OBJECTIVES: To ascertain the predictors of blood transfusions for adult patients undergoing different types of multilevel spine surgery. SUMMARY OF BACKGROUND DATA: Blood loss and transfusion requirements during and after multilevel spine surgeries have always been perceived as great. Identifying the predictors of blood transfusion with this type of surgery may aid in reducing the amount of blood loss and the transfusion requirements. METHODS: The charts of 244 adult patients who underwent multilevel spine surgery from January 1994 to July 1995 were retrospectively reviewed. RESULTS: A large percentage of patients required blood transfusion. The significant determinants for increased amounts of allogeneic red blood cell units transfused on the day of surgery using linear multiple regression modeling were low preoperative hemoglobin concentration, tumor surgery, increased number of posterior levels surgically fused, history of pulmonary disease, decreased amount of autologous blood available, and no use of the Jackson table (R2 = 0. 63). The significant determinants for an increased amount of autologous red blood cell units transfused on the day of surgery using linear multiple regression modeling were increased autologous red blood cells available, low preoperative hemoglobin concentration, and increased number of posterior levels surgically fused (R2 = 0. 60). CONCLUSION: The need for transfusion is associated with multiple factors, suggesting that a multifaceted, integrated approach may be necessary to reduce this risk. 相似文献
5.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
6.
Kinney MA Warner ME vanHeerden JA Horlocker TT Young WF Schroeder DR Maxson PM Warner MA 《Anesthesia and analgesia》2000,91(5):1118-1123
Pheochromocytomas and paragangliomas are often surgically curable. However, resection of these tumors can be life threatening. We undertook this study to determine the frequency of, and risk factors for, perioperative complications in patients undergoing resection of pheochromocytoma or paraganglioma. We retrospectively reviewed the medical records of patients during 1983-1996 who underwent surgical resection of catecholamine-secreting pheochromocytoma or paraganglioma. Preoperative risk factors, adverse intraoperative events, and complications occurring in the 30 days after operation were recorded. Blood pressures were collected from manual records. The ranked sum test and Fisher's exact test were used for analyses. Adverse perioperative events or complications occurred in 45 of 143 patients (31.5%; exact 95% confidence interval, 24.0% to 39.8%). Of these 45 patients, 41 experienced one or more adverse intraoperative events. The most common adverse event was sustained hypertension (36 patients). There were no perioperative deaths, myocardial infarctions, or cerebrovascular events. Preoperative factors univariately associated with adverse perioperative events included larger tumor size (P: = 0.007), prolonged duration of anesthesia (P: = 0.015), and increased levels of preoperative urinary catecholamines and catecholamine metabolites: vanillylmandelic acid (P: = 0.019), metanephrines (P: = 0.004), norepinephrine (P: = 0. 014), and epinephrine (P: = 0.004). Despite premedication of most patients with phenoxybenzamine and a beta-adrenergic blocker, varying degrees of intraoperative hemodynamic lability occurred. Implications: Few patients who had pheochromocytoma or paraganglioma resection experienced significant perioperative morbidity and none died in the largest retrospective study on this topic to date. This study confirms the very good perioperative outcomes demonstrated in smaller studies on this high-risk population, and identifies several risk factors for adverse outcomes. 相似文献
7.
Hyperbaric oxygen therapy improves angiogenesis and bone formation in critical sized diaphyseal defects 下载免费PDF全文
JP Grassmann J Schneppendahl AR Hakimi M Herten M Betsch TT Lögters S Thelen M Sager M Wild J Windolf P Jungbluth M Hakimi 《Journal of orthopaedic research》2015,33(4):513-520
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015. 相似文献
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9.
Horlocker TT 《Thrombosis research》2001,101(1):V141-V154
Spinal and epidural anesthesia/analgesia provide several advantages over systemic opioids, including superior analgesia, reduced blood loss and need for transfusion, and decreased incidence of thromboembolic complications. However, patients hospitalized for major surgery often receive an anticoagulant and/or antiplatelet medication perioperatively to prevent venous thrombosis and pulmonary embolism, although the pharmacologic agent, degree of anticoagulation desired, and duration of therapy remain controversial. These patients are often not considered candidates for spinal or epidural anesthesia/analgesia because of a theoretically greater risk of spinal hematoma. Spinal hematoma is a rare and potentially catastrophic complication of spinal or epidural anesthesia. The incidence of neurologic dysfunction resulting from hemorrhagic complications associated with central neural blockade is estimated to be less than 1 in 150,000 epidural and less than 1 in 220,000 spinal anesthetics. The decision to perform neuraxial blockade on these patients must be made on an individual basis, weighing the risk of spinal hematoma from needle or catheter placement against the theoretical benefits gained. Familiarity with the pharmacology of hemostasis-altering drugs, as well as case reports and clinical studies involving patients undergoing neuraxial blockade while receiving these medications will guide the clinician faced with this difficult decision. 相似文献
10.
Hoang L Phuong Tran TT Nga Phan T Giao Le Q Hung Tran Q Binh Nguyen V Nam Nico Nagelkerke Peter J de Vries 《BMC health services research》2010,10(1):275