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Antioxidant defence during cardiopulmonary bypass surgery.   总被引:1,自引:0,他引:1  
OBJECTIVE: Cardiac surgery may lead to severe oxidative stress due to formation of oxidation products generated during ischemia and reperfusion. We investigated to which extent oxidative stress influences a number of endogenous antioxidants and markers of cellular activation. METHODS: At six time points blood was withdrawn from patients undergoing coronary artery bypass grafting, using the on-pump procedure. RESULTS: Both glutathione peroxidase and superoxide dismutase show a gradual and strong increase in activity during surgery (40 and 30%, respectively), returning to baseline values 24 h after surgery. The total antioxidant capacity has a maximum increase of 60%. Markers of cellular activation, such as eosinophil cationic protein and tryptase also increase during the procedure. CONCLUSION: Cardiac surgery results in systemic inflammation accompanied or caused by severe oxidative stress. The human body has a strong innate oxidative defence screen, which is probably not sufficient to fully compensate for the total amount of oxidative damage.  相似文献   
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目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础.  相似文献   
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PURPOSE: This phase III randomized trial evaluated survival as well as neurologic and neurocognitive function in patients with brain metastases from solid tumors receiving whole-brain radiation therapy (WBRT) with or without motexafin gadolinium (MGd). PATIENTS AND METHODS: Patients were randomly assigned to 30 Gy of WBRT +/- 5 mg/kg/d MGd. Survival and time to neurologic progression determined by a blinded events review committee (ERC) were coprimary end points. Standardized investigator neurologic assessment and neurocognitive testing were evaluated. RESULTS: Four hundred one (251 non-small-cell lung cancer) patients were enrolled. There was no significant difference by treatment arm in survival (median, 5.2 months for MGd v 4.9 months for WBRT; P =.48) or time to neurologic progression (median, 9.5 months for MGd v 8.3 months for WBRT; P =.95). Treatment with MGd improved time to neurologic progression in patients with lung cancer (median, not reached for MGd v 7.4 months for WBRT; P =.048, unadjusted). By investigator, MGd improved time to neurologic progression in all patients (median, 4.3 months for MGd v 3.8 months for WBRT; P =.018) and in lung cancer patients (median, 5.5 months for MGd v 3.7 months for WBRT; P =.025). MGd improved neurocognitive function in lung cancer patients. CONCLUSION: The overall results did not demonstrate significant differences by treatment arm for survival and ERC time to neurologic progression. Investigator neurologic assessments demonstrated an MGd treatment benefit in all patients. In lung cancer patients, ERC- and investigator-determined time to neurologic progression demonstrated an MGd treatment benefit. MGd may improve time to neurologic and neurocognitive progression in lung cancer.  相似文献   
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BACKGROUND: In a subset of coronary surgery patients, a transient increase in cardiac load by leg elevation resulted in a decrease in maximal rate of pressure development (dP/dtmax) and a major increase in end-diastolic pressure (EDP). This impairment of left ventricular (LV) function appeared to be related to a deficient length-dependent regulation of myocardial function. The present study investigated whether analysis of transmitral flow patterns with transesophageal echocardiography constituted a noninvasive method to identify these patients. METHODS: High-fidelity LV pressure tracings and transmitral flow signals were obtained in 50 coronary surgery patients during an increase in cardiac load by leg elevation. Using linear regression analysis, changes in transmitral E-wave velocity and deceleration time (DT) were related to changes in dP/dtmax and EDP. RESULTS: Changes in dP/dtmax with leg elevation were closely related to corresponding changes in E-wave velocity (r = 0.81; P < 0. 001) and to changes in DT (r = 0.78; P < 0.001). Similarly, changes in EDP were related to changes in E-wave velocity (r = 0.83; P < 0. 001) and to changes in DT (r = 0.84; P < 0.001). The decrease in dP/dtmax and the major increase in EDP in some patients was associated with an increase in E-wave velocity and a decrease in DT, indicating development of a restrictive LV filling pattern. CONCLUSIONS: Impairment of LV function with leg elevation was associated with the development of a restrictive transmitral filling pattern. Analysis of transmitral flow patterns by means of transesophageal echocardiography therefore allowed noninvasive identification of a subset of coronary surgery patients with impaired length-dependent regulation of LV function.  相似文献   
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 目的:探讨上皮样血管瘤(EH)的临床及组织病理学特征。 方法:回顾性分析16例已确诊患者的临床及病理资料,并对相关文献进行综述。 结果:16例患者中女8例,男8例;平均年龄(45.44±12.52)岁;病程3个月~20年;皮损主要表现为红色至暗红色丘疹、结节,可伴瘙痒和糜烂,好发于头皮、耳部,其中发生在头部10例、耳部5例、外阴1例;皮损单发者5例,多发者11例。皮损组织病理学检查均具有典型的血管增生,管壁增厚,内皮细胞呈上皮样突向管腔,管周大量淋巴细胞及嗜酸性粒细胞浸润。结论:上皮样血管瘤少见,诊断需要临床与病理密切结合。加强对该病的认识,可避免误诊误治。  相似文献   
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In this prospective, randomized, open controlled study we compared the effects on net red blood cell loss of 6% hydroxyethyl starch 130/0.4 (HES: n = 64) and 3% modified fluid gelatin (GEL: n = 68) administered for intravascular volume management in patients undergoing coronary surgery. Blood losses were calculated from determination of circulating blood volume and measurement of preoperative and postoperative hematocrit. Amount of colloids that could be administered was limited to 50 mL/kg. If additional fluids were required, balanced crystalloid solution was used. Anesthetic and surgical techniques were standardized. Both groups were similar with regard to demographic and intraoperative variables. Total study drug was 48.9 +/- 17.2 mL/kg in the HES group and 48.9 +/- 14.6 mL/kg in the GEL group. Total red blood cell loss was 544 +/- 305 mL in the HES group and 504 +/- 327 mL the GEL group. Measured blood losses were also similar in both groups (HES, 19.4 +/- 12.3 mL/kg; GEL, 19.2 +/- 14.5 mL/kg). Exposure to allogeneic blood product was comparable in both groups. In the conditions of the present study, HES 130/0.4 up to 50 mL/kg is a valuable alternative to modified fluid gelatin for plasma volume expansion during and after cardiac surgery.  相似文献   
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The finding of a cardiac myxoma usually implies immediate consequent surgical excision to prevent embolic events. Reports with documented growth rate are therefore very rare, and the actual growth rate remains a controversial issue. We report the growth of a left atrial myxoma in an asymptomatic 65‐year‐old patient with several years of follow up for aortic valve disease. A MEDLINE search with the terms “cardiac myxoma and tumor growth” was performed. The calculated growth rate showed an average growth rate of 0.49 cm/month. These reports suggest that the growth rate of myxomas may be faster than is usually thought. (Echocardiography 2010,27:E128‐E131)  相似文献   
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