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81.
目的:观察和分析细胞膜有关的能量代谢状态改变对正常及脓毒症大鼠的不同类型骨骼肌乳酸产生量的影响.方法:借助大鼠脓毒症模型,建立伸趾长肌和比目鱼肌的充分供氧离体孵育系统,利用特异性Na+、K+、ATP酶抑制剂--哇巴因,干预细胞膜钠钾泵的活性,采用NADH荧光探针方法,检测骨骼肌组织细胞乳酸的产生量及其变化.结果:①应用哇巴因可显著降低正常及脓毒症大鼠肌肉组织的乳酸产生量;②哇巴因对伸趾长肌有氧糖酵解过程的抑制作用较比目鱼肌更为明显.结论:在正常和脓毒症情况下,肌肉组织细胞有关功能活动的增强而导致的Na+、K+、ATP酶活性升高是其乳酸产生增加的重要原因.  相似文献   
82.
血清Ⅳ型胶原测定在肾移植中的意义   总被引:2,自引:2,他引:0  
目的:探讨血清Ⅳ型胶原(Ⅳ-C)动态变化在肾移植术后监测中的意义。方法:检测61例肾移植患者血清Ⅳ-C浓度,观察不同病情状况时血清Ⅳ-C浓度的改变。结果显示:肾移植术前及术后动态测定血清Ⅳ-C浓度有助于早期诊断和鉴别诊断急性排斥反应(AR)、急性肾小管坏死(ATN)和感染,可作为肾移植监测的一个辅助指标。  相似文献   
83.
Mixed bacterial vaccine (MBV) was employed in the multi-modality treatment of hepatocellular carcinoma (HCC) during 1985-1988. Thirty eight patients undergoing palliative resection and cisplatin therapy (Series 1) and 48 patients with unresectable HCC who received hepatic artery ligation + intraarterial cisplatin infusion + radiotherapy (Series 2) were randomized to receive MBV or not. In series 1, the 1- and 2-year survival rates of MBV group and control were 75% vs 58% (P = 0.19) and 45% vs 39% (P = 0.23). In series 2, the 1-, 2- and 3-year survival rates were 59%, 41% and 41% for MBV group and 39%, 25% and 20% for the control, respectively (P1 = 0.07, P2 = 0.09, P3 = 0.07). In addition, MBV improved the "second look" resection rate to 40% as compared to 17% in the control (P greater than 0.05). MBV could also prevent such immunosuppression as decrease of macrophage activity caused by radiotherapy. We consider MBV a potential nonspecific immunostimulant in the multimodality treatment of HCC.  相似文献   
84.
Monette  FC; Holden  SA 《Blood》1982,60(2):527-530
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells.  相似文献   
85.
将藻酸盐-粘液型铜绿假单胞菌接种于免疫抑制大鼠,感染两周后,应用菌落计数法测定大鼠肺内存活菌数,光镜、透射电镜观察大鼠肺部病理改变,ELISA方法测定大鼠外周血IgG抗体,建立了稳定的铜绿假单胞菌生物被膜相关肺慢性感染大鼠模型,探讨铜绿假单胞菌生物被膜相关感染免疫逃逸现象。  相似文献   
86.
目的 对比研究头孢硫脒(CTM)、头孢唑林(CEZ)、头孢映辛(CXM)、头孢曲松(CRO)、苯唑西林(MPIPC)、万古霉素(VCM)对99株临床分离革兰氏阳性球菌的抗菌活性。方法采用琼脂平板稀释法测定最低抑菌浓度(MIC)。结果 CTM对32株金黄色葡萄球菌的MIC50、MIC90均为0.5mg/L,低于CRO,CTM对29株表皮葡萄球菌的MIC50、MIC90分别为0.125和8mg/L,是CRO的l/16,对9株甲氧西林耐药的葡萄球菌(MRS)的范围与CXM相近;CTM对粪肠球菌的抗菌活性与万古霉家相仿,强于CEZ、CXM、CRO、LGIPC。结论头孢硫腺对葡萄球菌和粪肠球菌具有很强的体外抗菌活性。  相似文献   
87.
The purpose of this study was to determine whether micturition reflexes are altered in aged rats. Voiding frequencies and awake cystometrograms (CMGs) were measured in young (3–5 months old) and aged (24 months) F344 male rats. Bladder contractions induced by subcutaneous apomorphine and intravesical capsaicin stimulation were measured using awake CMGs. Urodynamic parameters were compared. Aged rats voided less frequently (4.1 vs 6.9 times/18 h, P=0.006), with a higher volume per void (1.1 vs 0.7 ml, P=0.02) and had a higher micturitional threshold pressure (8.7 vs 4.6 mmHg, P=0.0001) than the young rats. Apomorphine induced a higher frequency of bladder contractions in aged animals compared to young animals (5.5 vs 3.1 contractions/min, P=0.03). Intravesical capsaicin caused a lower pressure bladder response in the aged rats (38.5 vs 70.6 mmHg, P=0.01) compared to the young rats. Bladder afferents and central micturition pathways may be altered in aged rats. Impaired bladder contractility in the elderly may be exacerbated by reduced sensory input, whereas the propensity for detrusor instability could result from altered central processing. This study demonstrated the utility of the F344 animal model to study micturitional changes resulting from aging. Received: 14 April 2000 / Accepted: 4 July 2000  相似文献   
88.
Chai TC  Zhang C  Warren JW  Keay S 《Urology》2000,55(5):643-646
OBJECTIVES: A highly effective treatment for interstitial cystitis (IC) remains elusive. We determined whether sacral third nerve root (S3) percutaneous neurostimulation (PNS) might be effective in relieving symptoms of IC, as well as in normalizing urinary factors that are specifically altered in IC. METHODS: Six consecutive patients with symptoms and cystoscopic findings compatible with IC underwent 5 days of continuous S3 neurostimulation by way of leads placed percutaneously into the S3 foramen. Patients filled out voiding frequency diaries and pain and urgency questionnaires before PNS and at the end of PNS when the leads were removed. Urine specimens were collected at these two time points and measured for heparin-binding epidermal growth factor-like growth factor (HB-EGF) by enzyme-linked immunosorbent assay and for antiproliferative factor (APF) activity by (3)H-thymidine uptake by normal human bladder urothelial cells. RESULTS: S3 PNS significantly improved all measured parameters toward normal values. Voiding frequency decreased twofold from 23.1 +/- 4.6 to 10.6 +/- 4.0 voids daily during PNS (P = 0.0001). Pelvic pain on a scale of 1 to 10 decreased from 7.0 +/- 1.6 to 2.3 +/- 3.2 (P = 0.05). Urinary urgency on a scale of 1 to 10 decreased from 6.0 +/- 2.2 to 1.8 +/- 1.7 (P = 0. 02). Urinary HB-EGF concentration increased sevenfold from 1.5 +/- 2. 1 to 11.0 +/- 1.7 ng/mL (P <0.0001), and urinary APF activity decreased from -76.1% +/- 31% to -4.5% +/- 8.8% (P = 0.005). CONCLUSIONS: S3 PNS significantly decreased symptoms and normalized urinary HB-EGF and APF activity in patients with IC. These results suggest that permanent S3 PNS may be beneficial in treating IC.  相似文献   
89.
The aims of the present study were to determine the rate of misinterpretation of non‐contrast cranial CT scans by emergency specialists and trainees compared with specialist radiologists, and the proportion of misinterpretations that is consequential. A 12‐month prospective blinded cohort study was performed. One‐hundred and ninety of 1282 scans (14.8%) were misinterpreted, and 78 of these (41.1%) were of potential or actual consequence. We conclude that the performance of senior emergency department staff in non‐contrast cranial CT interpretation is no better than moderately good, and a large proportion of misinterpretations are of potential or actual clinical consequence.  相似文献   
90.
大面积烧伤后多器官功能障碍综合征的临床防治   总被引:30,自引:0,他引:30  
Sheng Z  Yang H  Chai J  Guo Z  Shen C  Zhang C 《中华外科杂志》2000,38(6):435-438
目的 将临床与实验研究所得结果应用于临床治疗 ,分析其对降低严重烧伤患者多器官功能障碍综合征 (MODS)发病率的作用。 方法 总结自 1970年 1月至 1999年 10月共收治的严重烧伤 (烧伤面积均大于 30 %TBSA)患者 6 5 7例 ,以 1990年 1月 1日为界分为 2组。 2组的伤情有可比性。 1990年 1月至 1999年 10月之间的患者广泛地应用了新的治疗措施 ,主要为及时、快速、充分的液体复苏 ,应用山莨菪碱恢复肠道血供 ,氧自由基清除剂阻止氧自由基的损害 ,休克期广泛切痂、植皮 ,早期经口营养 ,主要器官功能支持等。 结果  1990年 1月前 36 9例 ,MODS的发病率为 17 3% ,病死率为 87 5 % ;1990年 1月至 1999年 10月之间 2 88例的MODS发病率为 6 9% ,病死率为 40 0 % ,两组结果差异有显著意义。 结论 严重烧伤患者在治疗中减轻或消除MODS的病因或诱因的措施 ,可以显著地降低MODS的发病率。  相似文献   
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