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491.
492.
BACKGROUND: The increasing trend toward outpatient surgery has stimulated the development of techniques focused on decreasing perioperative and postoperative pain. Pain control infusion pumps are gaining in popularity in orthopaedic procedures to control postoperative pain. HYPOTHESIS: Continuous infusion of bupivacaine via a catheter placed intra-articular into the knee after anterior cruciate ligament reconstruction using ipsilateral autograft quadrupled semitendinosus will decrease postoperative pain scores and narcotic and NSAID consumption. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Three randomized study groups of 21 subjects were evaluated: group I, 0.25% bupivacaine infused intra-articular at 4 mL/hour for 72 hours (study); Group II, 0.9% saline infused intra-articular at 4 mL/hr for 72 hours (placebo); Group III, no intra-articular infusion catheter (control). Each subject received general anesthesia and preemptive intra-articular anesthesia. Visual analog scale pain scores and analgesic use were compiled for the 96-hour study period. RESULTS: With the exception of significantly higher total narcotic usage in the control group compared with the study group only for the time period of 48 to 72 hours, there were no other statistically significant differences between each of the study groups with respect to pain and narcotic and NSAID use for the entire study period. CONCLUSION: The continuous infusion of intra-articular bupivacaine via pain control infusion pumps after anterior cruciate ligament reconstruction using ipsilateral autograft quadrupled semitendinosus cannot be supported when postoperative visual analog scale pain scores and analgesic use are the rationale for justification.  相似文献   
493.
  • 1 Because diabetic hearts have an increased threshold for cardioprotection by ischaemic preconditioning (IPC), we hypothesized that protection by l ‐glutamate during reperfusion is restricted in Type 2 diabetic hearts. Previously, we found that l ‐glutamate‐mediated postischaemic cardioprotection mimics IPC.
  • 2 Rat hearts were studied in a Langendorff preparation perfused with Krebs’–Henseleit solution and subjected to 40 min global no‐flow ischaemia, followed by 120 min reperfusion. l ‐Glutamate (0, 15 and 30 mmol/L) was added to the perfusate during reperfusion of hearts from non‐diabetic (Wistar‐Kyoto) and diabetic (Zucker diabetic fatty (ZDF)) rats, studied at 16 weeks of age. The infarct size (IS)/area‐at‐risk (AAR) ratio was the primary end‐point. Expression of l ‐glutamate excitatory amino acid transporter (EAAT) 1 (mitochondrial) and EAAT3 (sarcolemmal) was determined by quantitative polymerase chain reaction and immunoblotting.
  • 3 The ISS/AAR ratio did not differ between control hearts from Wistar‐Kyoto and ZDF rats (0.52 ± 0.03 and 0.51 ± 0.04, respectively; P = 0.90). l ‐Glutamate (15 mmol/L) significantly reduced the IS/AAR ratio in non‐diabetic hearts, but not in diabetic hearts, compared with their respective controls. The higher concentration of l ‐glutamate (30 mmol/L) reduced infarct size in diabetic hearts to the same degree as in non‐diabetic hearts (IS/AAR 0.35 ± 0.03 (P = 0.002) and 0.34 ± 0.03 (P = 0.004), respectively). The mitochondrial l ‐glutamate transporter EAAT1 was downregulated in hearts from ZDF rats at both the mRNA and protein levels (P < 0.0005 and P < 0.0001, respectively). However, there was no change in EAAT3 expression at the protein level. Myocardial l ‐glutamate content was increased by 43% in diabetic hearts (P < 0.0001).
  • 4 Hearts from obese diabetic rats have an elevated threshold for metabolic postischaemic cardioprotection by l ‐glutamate. These findings may reflect underlying mechanisms of inherent resistance against additional cardioprotection in the diabetic heart.
  相似文献   
494.
PURPOSE: We determined the usefulness of computerized tomographic urography for the initial evaluation of patients with hematuria as an alternative to excretory urography. MATERIALS AND METHODS: A total of 259 patients (140 men and 119 women), age range 20 to 100 (mean 59.4) years, underwent computerized tomographic urography for the evaluation of hematuria and were available for followup. A cohort of 253 patients (153 men, 100 women), age range 21 to 92 (mean 57.6) years, underwent conventional excretory urography and were evaluated for comparison. RESULTS: A source of hematuria was identified in 107 patients (41.3%) in the computerized tomographic urography cohort and in 103 patients (40.7%) in the excretory urography cohort. Computerized tomographic urography alone identified a source of hematuria in 25.5% of these patients with the most commonly diagnosed lesions being renal calculi (18.9%), ureteral calculi (2.7%) and renal pelvic masses (2.3%) in the upper tract (0.94 sensitivity), and bladder masses (8.1%), prostatic abnormalities (5.4%) and inflammatory disorders (3.5%) in the lower tract (0.40 sensitivity, 0.99 specificity). The overall detection rate (19.5%), most commonly diagnosed lesions, and lower urinary tract sensitivity and specificity were similar in the excretory urography cohort. However, excretory urography exhibited a markedly lower sensitivity in detecting upper tract lesions (0.50). CONCLUSIONS: Computerized tomographic urography exhibited a significantly higher sensitivity than conventional excretory urography in detecting upper tract pathology (94.1% vs 50%). However, sensitivity for detecting lower tract lesions was low (40% or less), suggesting that computerized tomographic urography offers a comprehensive alternative to excretory urography but does not obviate the need for adjunctive cystourethroscopy for accurate evaluation of the lower urinary tract.  相似文献   
495.
目的:观察普伐他汀、阿司匹林联用对家兔颈动脉血管成形术后内膜增殖进展的影响及其作用机制。方法:实验于2002-03/12在北京中医药大学教育部中医内科学重点学科实验室完成。雄性日本大耳白兔30只,体质量1.8~2.0kg,动物适应性喂养1周后随机数字表法分为正常对照组(n=9)、假手术组(n=6)、模型组(n=9)、治疗组(n=6)。模型组和治疗组动物氯胺酮、速眠新混合肌注麻醉,沿气管正中切开皮肤,剥离颈总动脉,给予电刺激。术后第2天开始饲喂高脂饲料(胆固醇:0.7%,猪油:3%,普通饲料96.3%);正常对照组无任何干预措施;假手术组仅剥离颈总动脉,不做电刺激,喂高脂饲料;动物连续喂养8周后超声评价颈总动脉,根据B超选择颈总动脉有斑块或血流明显改变者作颈总动脉球囊扩张术。正常对照组、模型组、假手术组喂普通饲料,治疗组喂普伐他汀与阿司匹林含药饲料(普伐他汀5.046mg/kg,阿司匹林2.268g/kg),4周后测血脂和C-反应蛋白浓度、血清一氧化氮及转化生长因子β水平,观察颈动脉组织病理形态学改变,半定量分析增生内膜中胶原含量的变化,免疫组织化学方法分析增生内膜中巨噬细胞和平滑肌细胞阳性百分率。结果:纳入大耳白兔30只,正常对照组中途死亡1只,死因为牙齿畸型影响进食;模型组1只因电刺激8周时超声评价颈动脉未形成斑块及血流无明显改变而剔出实验,进入分析28只。与模型组比,普伐他汀与阿司匹林联用4周后,治疗组胆固醇及三酰甘油水平明显下降[(4.12±2.30),(0.74±0.17)mmol/L;(0.47±0.27),(0.39±0.14)mmol/L;P<0.05],血清C-反应蛋白水平和转化生长因子β水平均降低[(0.86±0.27),(0.57±0.30)mg/L;(3.45±0.77),(3.23±0.34)ng/L;P<0.05],一氧化氮水平升高[(41.79±35.78),(90.14±32.54)mmol/L;P<0.05],动脉内膜增殖程度明显减轻,管腔狭窄率降低,内中膜厚度及内中膜面积比降低[(71.91±14.90)%,(47.20±18.74)%;(0.41±0.17),(0.26±0.04)mm;1.66±0.63,0.78±0.34;P均<0.05],动脉内膜胶原含量减少(30.92±10.05,21.93±5.81,P<0.01),动脉内膜巨噬细胞阳性百分率降低[(13.94±4.91)%,(7.29±7.28)%,P<0.05],平滑肌细胞含量无明显差异(38.37±5.67,35.79±10.68,P>0.05)。结论:普伐他汀与阿司匹林联用具有抑制内膜增生和减少新生内膜胶原含量的作用,其机制与两药抑制炎症反应、保护内皮功能及抑制细胞外基质生成等有关。  相似文献   
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