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51.
Objective: To analyze data from a large multicenter study to determine whether pregnancy and delivery rates decrease with repeated IVF-ET cycles.

Design: Multicenter retrospective study.

Setting: Participating centers from the Society of Assisted Reproductive Technology.

Patient(s): Fifty-four centers contributed 4,043 cycles of oocyte retrieval for uterine transfer.

Intervention(s): Oocyte retrieval for uterine transfer.

Main Outcome Measure(s): Pregnancy and delivery rates, analyzed according to age, program success rate, and whether the program was doing assisted hatching.

Result(s): Pregnancy and delivery rates for cycles 1, 2, 3, 4, and >4 were 33.7% and 27.0%, 33.9% and 27.4%, 28.9% and 23.4%, 25.9% and 16.1%, and 21.0% and 15.4%, respectively. The pregnancy rate decreased significantly for >4 cycle; delivery rate decreased significantly for cycles 4 and >4. Assisted hatching was strongly related to better odds of pregnancy (OR, 1.50) and delivery (OR, 1.44) in women under age 40, and for pregnancy (1.64) in women age 40–42 years.

Conclusion(s): Success rates do not decrease markedly with repeated IVF attempts, and the decrease did not change with program success rate, suggesting the IVF population is not markedly heterogeneous. Uncontrolled studies of new treatments for cycle repeaters cannot assume that success rate is poor without a treatment change.  相似文献   

52.
剖宫产术后自控镇痛对母婴的影响   总被引:15,自引:0,他引:15  
目的 观察剖宫产术后产妇自控镇痛对母婴的影响。方法  2 0 0 2年 1月至 2 0 0 3年 1月首都医科大学附属复兴医院将剖宫产产妇 2 16例分为观察组和对照组 ,两组均为连续硬膜外麻醉 ,手术结束时 ,观察组将自控镇痛泵接在硬膜外管上。术后分别取产妇肘静脉血、初乳、尿及新生儿尿 ,测定吗啡含量 ;观察镇痛效果及副反应。结果 与对照组比较观察组镇痛效果明显 (P <0 0 5 )。观察组血吗啡质量浓度 5 0~ 12 6 0 μg/L ,初乳吗啡质量浓度 5 0~ 33 6 μg/L ,91 8%的产妇尿吗啡呈阳性 ,12 7%的新生儿尿吗啡呈阳性。随访 1年两组婴儿的体格及发育商比较 ,P >0 0 5。结论 剖宫产术后硬膜外腔应用吗啡镇痛 ,对产妇及新生儿是安全可行的  相似文献   
53.
OBJECTIVES: We planned to determine whether the concentration of human chorionic gonadotropin (hCG) in cervical secretions could be a useful marker for accurate diagnosis of preterm labor, and whether the use of cervical hCG assay in combination with the Bishop score would improve the prediction of delivery within 7 days, and to determine the cut-off values for hCG in prediction of delivery within 100 h, 7 and 14 days, as well as before 35 and 37 weeks of gestation in a group of women at high risk for preterm delivery. METHODS: The study was conducted in the perinatology department of Zeynep Kamil Women and Children Diseases Education and Research Hospital between February 2002 and February 2003. One hundred and two subjects with a diagnosis of threatened preterm labor with intact membranes were included in the study. For hCG measurements, a cotton swab was rolled intracervically for 10 s to absorb fluid. Bishop scores were assessed. The correlation test was employed for the variables influencing hCG values. The ROC curve analysis was used to establish an optimal cut-off concentration for cervical hCG and an optimal cut-off level for Bishop score. The continuous variables were analyzed by the unpaired, independent, two-tailed t-test and categorical data were analyzed by the chi-square test. RESULTS: A significant positive correlation was present between the cervical hCG concentrations and Bishop scores (r=0.72, P<0.0001), and a highly negative correlation between the cervical hCG concentrations and the time interval from sampling time until delivery (r=-0.80, P<0.0001) was detected. The cut-off value for cervical hCG concentration and its sensitivity, specificity, positive and negative predictive values, accuracy, relative risk and likelihood ratio for accurate determination of delivery within 100 h were > or =32 mIU/ml, 98%, 55%, 70%, 96%, 77%, 19.68 and 2.18, respectively. However, these values were > or =32 mIU/ml, 97%, 84%, 89%, 95%, 92%, 17.37 and 6.06, respectively, for prediction of delivery within 7 days; > or =30 mIU/ml, 97%, 79%, 87%, 94%, 89%, 15.15 and 4.62, respectively, for prediction of delivery within 14 days; > or =33 mIU/ml, 89%, 92%, 94%, 83%, 90%, 5.83 and, 11.55, respectively, for prediction of delivery before 35 weeks; and finally > or =27 mIU/ml, 76%, 50%, 85%, 37%, 71%, 1.34 and 1.52, respectively, for prediction of delivery before 37 weeks. CONCLUSIONS: Cervical hCG expression seems to be rewarding in accurate diagnosis of preterm labor. This test has the advantage of low cost and wide availability.  相似文献   
54.
Elective caesarean section for women in labour with an immature baby might reduce the chances of fetal or neonatal death, but might also increase the risk of maternal morbidity. A review (updated in February 2004) of randomised trials comparing a policy of elective caesarean section versus expectant management with recourse to caesarean section produced six studies involving only 122 women. Differences in fetal outcome did not reach significance, but mothers undergoing elective caesarean section were more likely to have serious morbidity. Scientifically, the evidence remains inadequate. Clinically, the recommendation is that prematurity is not, in itself, an indication for caesarean section. In a survey from Israel, published in December 2004, of 2955 very low birthweight infants born at 24–34 weeks of gestation, the overall caesarean section rate was 51.7%, and the mortality rate among babies prior to discharge was lower after caesarean section (13.2 versus 21.8%). After adjustment using multiple logistic regression, caesarean section had no effect on survival except in a subgroup with amnionitis, and it was again concluded that caesarean section cannot be routinely recommended unless there are other indications. A decision model developed in the USA has compared costs and health outcomes of two options for managing labour at 24 weeks of gestation. The probabilities of both intact survival (16.8 versus 12.9%) and survival with major morbidity (39.2 versus 19.4%) are higher with willingness to perform caesarean section, but less aggressive management is the more cost-effective strategy. Large studies are few and recruitment to such studies is perceived as a major problem. For clinicians, the decision will be influenced by local circumstances.  相似文献   
55.
OBJECTIVE: To compare the perioperative outcomes of two cesarean section methods, the finger-assisted stretching technique (FAST), based on a modified Joel-Cohen method, with the traditional technique. METHODS: A retrospective review of the records of 416 women who underwent cesarean sections at Guro Hospital, Seoul, Korea, between May 1993 and December 2001 was performed. Of the 416 women, 283 underwent cesarean sections with FAST and 133 with the traditional technique. RESULTS: Operative time was significantly shorter with FAST (15.3 vs. 42.6 min, P<.05), and FAST was associated with lower blood loss (601 vs. 928 mL, P<.05) and shorter hospital stay (3.7 vs. 6.5 days, P<.05). There were no significant differences in wound infection, voiding difficulty, and postoperative adhesions between the two methods. CONCLUSION: These results suggest that FAST may be the better technique.  相似文献   
56.
研究了电致孔技术对睾酮透皮转运的影响,对电压、脉冲持续时间和电极的影响进行了初步探讨.结果表明,电致孔可增大药物的透皮转运速率及其累积透过量,且电力学参数与透皮吸收增量呈正相关,电极也明显影响电致孔透皮速率.  相似文献   
57.
58.
Recent studies in mouse models of cancer have shown that exercise improves tumor vascular function, thereby improving chemotherapy delivery and efficacy. However, the mechanisms underlying this improvement remain unclear and the effect of exercise on Ewing sarcoma (ES), a pediatric bone and soft tissue cancer, is unknown. The effect of exercise on tumor vascular hyperpermeability, which inversely correlates with drug delivery to the tumor, has also not been evaluated. We hypothesized that exercise improves chemotherapy efficacy by enhancing its delivery through improving tumor vascular permeability. We treated ES‐bearing mice with doxorubicin with or without moderate treadmill exercise. Exercise did not significantly alter ES tumor vessel morphology. However, compared to control mice, tumors of exercised mice had significantly reduced hyperpermeability, significantly decreased hypoxia, and higher doxorubicin penetration. Compared to doxorubicin alone, doxorubicin plus exercise inhibited tumor growth more efficiently. We evaluated endothelial cell sphingosine‐1‐phosphate receptors 1 and 2 (S1PR1 and S1PR2) as potential mediators of the improved vascular permeability and increased function afforded by exercise. Relative to tumors from control mice, vessels in tumors from exercised mice had increased S1PR1 and decreased S1PR2 expression. Our results support a model in which exercise remodels ES vasculature to reduce vessel hyperpermeability, potentially via modulation of S1PR1 and S1PR2, thereby improving doxorubicin delivery and inhibiting tumor growth more than doxorubicin alone does. Our data suggest moderate aerobic exercise should be tested in clinical trials as a potentially useful adjuvant to standard chemotherapy for patients with ES.  相似文献   
59.
目的:制备促黄体激素释放激素类似物(Luteinizing hormone-releasing hormone analogues,LHRHa)靶向紫杉醇脂质体(Paclitaxel liposomes,PTX-Lipo),研究其在体外增强紫杉醇(Paclitaxel,PTX)对卵巢癌A2780/DDP细胞的抑制作用。方法:采用薄膜超声法制备PTX-Lipo与LHRHa靶向紫杉醇脂质体(LHRHa-Paclitaxel liposomes,LHRHa-PTX-Lipo),用透射电镜考察脂质体形态;高效液相色谱法测定2种PTX-Lipo的包封率;激光共聚焦法通过卵巢癌A2780/DDP细胞对4-氟-7-硝基-2,1,3-苯并氧杂恶二唑荧光素的摄取检测来反映细胞对NBD-Lipo与NBD-LHRHa-Lipo的摄取情况;MTT法及细胞克隆形成实验检测LHRHa-PTX-Lipo体外对卵巢癌细胞的生长抑制情况。结果:制备LHRHa-PTX-Lipo的平均粒径123.4 nm,包封率在90%以上;A2780/DDP细胞对NBD-LHRHa-Lipo组的荧光摄取明显高于NBD-Lipo组;LHRHa-PTX-Lipo对A2780/DDP细胞的生长及克隆形成抑制明显高于PTX组及PTX-Lipo组(P<0.05)。结论:采用薄膜超声法制备的LHRHa-PTX-Lipo可使药物在靶部位聚集,增强药物对卵巢癌细胞的抑制作用。  相似文献   
60.
目的 探讨瘢痕子宫使用双球囊导管促宫颈成熟及引产后阴道分娩的安全性和有效性.方法 以2016年1月—2018年7月本院收治有阴道分娩条件和意愿的59例宫颈未成熟的足月瘢痕子宫作为研究组,以同期分娩的67例足月非瘢痕子宫宫颈未成熟的为对照组,两组均使用双球囊导管促宫颈成熟及引产,比较两组的母婴结局.结果 研究组孕产妇的年...  相似文献   
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