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11.
The aim of the study is to investigate the benefits and the limits in using the soft cup vacuum extractor on the fetal scalp during the caesarean section. MATERIAL AND METHODS: The prospective study includes 19 cases of caesarean sections (group A), with vacuum assisted delivery using the soft cup vacuum extractor on the fetal scalp (diameter 6 cm) and 25 cases (group B) of caesarean sections with usual, manual extraction of the head assisted by fundal compression. All of the patients had undergone a planned caesarean section on term in absence of uterine activity and preserved amniotic membranes. RESULTS: Our results doesn't show differences in the Apgar score on the first and 5-th minute in the newborns of the two groups. The duration of the scalp traction was significantly shorter (30 +/- 4 sec) in comparison to the classical manual extraction (53 +/- 21 sec). The mean duration for applying the vacuum cup was 10 sec and 25 sec for tractions. The total blood loose and total duration of the caesarean sections were shorter than in the control group. The applied traction with the vacuum cup was sufficient for head extraction and there was no need for additional fundal compression. In conclusion we consider that the extraction of the fetal head in high position in caesarean section with vacuum extractor is an easy, non traumatic and rapid method which can put away the need of rough and prolonged fundal compression and its consequences.  相似文献   
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目的:通过多中心临床研究分析高强度聚焦超声治疗不能手术胰腺癌的1年生存情况。方法:2013年1月到2014年1月,中国和保加利亚的不能手术的胰腺癌患者32例,男/女=20/12,年龄41~81(59.8±9.1)岁。胰腺癌病灶最大径20~60(39.3±9.6)mm,远处转移/无转移的患者18/14例。接受HIFU和/或化疗。记录术后并发症,疼痛变化和生存情况。使用Kaplan-Meier法计算总生存率和中位生存时间,比较化疗与否、是否发生远处转移的患者生存率有无差异(Log-Rank检验)。结果:术后1月,皮肤浅Ⅱ°烧伤者2例,经保守处理后1~2周愈合。伴有胰腺癌相关性疼痛症状的患者30例与术前比较,减轻的24例(80.0%),不变的5例(16.7%),加重的1例(3.3%)。所有患者的1年生存率为38.4%,中位生存时间为12个月。接受辅助化疗的患者1年生存率为57.4%,中位生存时间12月;未接受辅助化疗的患者1年生存率为20.8%,中位生存时间为6月;二者间比较有显著性差异。伴有远处转移的患者1年生存率为0%,中位生存时间为7月;无远处转移的患者1年生存率为49.2%,中位生存时间为12月;二者间比较无统计学差异。结论:中国和保加利亚的不能手术胰腺癌患者均能安全完成HIFU治疗,1年生存率和中位生存时间优于其它非手术治疗手段。辅助化疗能增加生存受益,远处转移是预后不良因素。  相似文献   
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Background and purposeThe association of leg length discrepancy (LLD) with a number of clinical disorders has made its determination a significant part of the physical examination. We believe that submalleolar causes of LLD may be under-acknowledged. The most common clinical method used to measure LLD is by tape from the anterior superior iliac spine (ASIS) to medial malleolus which disregards the potential for LLD arising from asymmetry in the foot distal to the tibiotalar joint.MethodsThe present pilot study involves a group of 5 volunteers (experimental group) and a group of 3 patients with flexible flat feet (clinical study). The differences in tibial tubercle height from the ground between full pronation and full supination were measured using the CODA MPX 30® system (Charnwood Dynamics Limited, Leicestershire, England). Correlations of the patterns within each group were produced.ResultsA significant relationship with leg lengths was found in the experimental group when they induced maximum pronation (R-squared = 0.62, p = 0.007) while an inverse relationship occurred with supination, although marginally significant (R-squared = 0.37, p = 0.064).ConclusionsWe have demonstrated that significant leg length discrepancy can occur in patients who do not have obvious deformity when non weight bearing. We recommend using the blocks method routinely. Appropriately measuring LLD is of vital importance to properly diagnosing and treating patients with unequal leg lengths or related symptoms.  相似文献   
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Recent evidence suggests that arginine vasopressin (AVP)-dependent aquaporin-2 expression is modulated by the extracellular calcium-sensing receptor (CaSR) in principal cells of the collecting duct, but the signaling pathways mediating this effect are unknown. Using a mouse cortical collecting duct cell line (mpkCCD(cl4)), we found that increasing the concentration of apical extracellular calcium or treating with the CaSR agonists neomycin or Gd(3+) attenuated AVP-dependent accumulation of aquaporin-2 mRNA and protein; CaSR gene-silencing prevented this effect. Calcium reduced the AVP-induced accumulation of cAMP, but this did not occur by increased degradation of cAMP by phosphodiesterases or by direct inhibition of adenylate cyclase. Notably, the effect of extracellular calcium on AVP-dependent aquaporin-2 expression was prevented by inhibition of calmodulin. In summary, our results show that high concentrations of extracellular calcium attenuate AVP-induced aquaporin-2 expression by activating the CaSR and reducing coupling efficiency between V(2) receptor and adenylate cyclase via a calmodulin-dependent mechanism in cultured cortical collecting duct cells.  相似文献   
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Target organs express antigens directly recognized by antigen-specific T cells, thereby precipitating rejection. When early T-cell activation is inhibited, there is a low risk of rejection. We sought to determine the predictive values of serial posttransplant blood cyclosporine trough (C(0)) concentrations to minimize the risk for a first rejection episode compared with 2-hour postdose (C(2)) drug concentrations. The final aim of the study was to identify a concentration range for the best predictive pharmacokinetic parameter that should be targeted to reduce the risk of rejection. This possibility was explored in 334 de novo kidney transplant recipients who participated in the prospective, multicenter Mycophenolate Steroid-Sparing Trial. Among measurements performed during the first 6 months postsurgery, cyclosporine C(0) levels measured early after transplantation were the strongest predictor of acute graft rejection. Levels within 300 to 440 ng/mL were associated with the lowest risk of rejection, while patients with levels lower than 300 ng/mL showed a more than double risk. Cyclosporine trough values predicted allograft rejection with an accuracy of 74%, while C(2) levels had no predictive value. These findings underline the need to target cyclosporine therapy early posttransplant to modulate T-cell activation.  相似文献   
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OBJECTIVE: To determine whether in the previous National Surgical Adjuvant Breast and Bowel Project (NSABP) studies of node-negative breast cancer there were either cohorts of patients with a prognosis favorable enough to preclude using systemic therapy or subsets of patients who failed to benefit from the treatments. DESIGN: Randomized clinical trials with stratification after surgery. SETTING: NSABP trials at institutions in the United States and Canada. PATIENTS: Data were collected on 731 eligible patients (Protocol B-13) with estrogen-receptor-negative tumors who randomly received either no therapy after surgery or sequential methotrexate and fluorouracil (M----F) followed by leucovorin. Data were also collected on 2834 patients (Protocol B-14) with estrogen-receptor-positive tumors who randomly received either placebo or tamoxifen treatment. The percentage of patients surviving disease-free was determined through 4 years of follow-up using life-table estimates. INTERVENTIONS: Protocol B-13 patients received 12 courses of M----F given intravenously on days 1 and 8 every 4 weeks. Leucovorin therapy was begun 24 hours after M----F administration. Protocol B-14 patients received 5-year treatment with either tamoxifen (10 mg twice daily by mouth) or placebo. RESULTS: When the outcome of untreated patients in either trial was related to the stratification variables, women were found to have a disease-free survival of less than 80% through 4 years of follow-up. This percentage is apt to decrease because the probability of treatment failure increases with time. In both trials, all subsets of women benefited from M----F or tamoxifen therapy. CONCLUSIONS: The disease-free survival of all cohorts of node-negative patients with estrogen-receptor-negative or estrogen-receptor-positive tumors was poor enough to justify systemic treatment. The benefits of the therapies used are insufficient to eliminate the need for assessing putatively better regimens.  相似文献   
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This review provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ASL in Dementia consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues to undergo rapid technical development, we believe that current ASL methods are robust and ready to provide useful clinical information, and that a consensus statement on recommended implementations will help the clinical community to adopt a standardized approach. In this review, we describe the major considerations and trade‐offs in implementing an ASL protocol and provide specific recommendations for a standard approach. Our conclusion is that as an optimal default implementation, we recommend pseudo‐continuous labeling, background suppression, a segmented three‐dimensional readout without vascular crushing gradients, and calculation and presentation of both label/control difference images and cerebral blood flow in absolute units using a simplified model. Magn Reson Med 73:102–116, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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Type 2 diabetes (T2D) disproportionally affects African Americans (AfA) but, to date, genetic variants identified from genome-wide association studies (GWAS) are primarily from European and Asian populations. We examined the single nucleotide polymorphism (SNP) and locus transferability of 40 reported T2D loci in six AfA GWAS consisting of 2,806 T2D case subjects with or without end-stage renal disease and 4,265 control subjects from the Candidate Gene Association Resource Plus Study. Our results revealed that seven index SNPs at the TCF7L2, KLF14, KCNQ1, ADCY5, CDKAL1, JAZF1, and GCKR loci were significantly associated with T2D (P < 0.05). The strongest association was observed at TCF7L2 rs7903146 (odds ratio [OR] 1.30; P = 6.86 × 10−8). Locus-wide analysis demonstrated significant associations (Pemp < 0.05) at regional best SNPs in the TCF7L2, KLF14, and HMGA2 loci as well as suggestive signals in KCNQ1 after correction for the effective number of SNPs at each locus. Of these loci, the regional best SNPs were in differential linkage disequilibrium (LD) with the index and adjacent SNPs. Our findings suggest that some loci discovered in prior reports affect T2D susceptibility in AfA with similar effect sizes. The reduced and differential LD pattern in AfA compared with European and Asian populations may facilitate fine mapping of causal variants at loci shared across populations.Type 2 diabetes (T2D) is a major public health problem affecting 25.8 million people in the U.S. (1). Marked racial differences in its prevalence have been observed, with African American (AfA) adults >40 years of age having nearly twofold higher prevalence than European Americans (27.1 and 15.5%, respectively) (2). In addition to socioeconomic and behavioral risk factors, genetic factors are likely contributors to T2D risk in AfA (3).Genome-wide association studies (GWAS) for T2D and related traits have successfully identified >50 loci with common genetic variants associated with T2D risk in primarily European-descent populations (414) and more recently in East and South Asians (1521). The reported index single nucleotide polymorphisms (SNPs) at these loci have been replicated in multiple populations (2224) but less successfully in AfA (2527). Although differences in environment and lack of study power may partly account for the lack of transferability across ethnicities, differences in linkage disequilibrium (LD) patterns, effect sizes, and risk allele frequency also likely impact the replication of index SNPs. Although the long-range LD in European populations allows for the identification of T2D loci using less dense markers, causal variants are not distinguishable from other nearby SNPs in high LD. This issue prompts the need to examine T2D loci in other populations with different allelic and LD architecture, which may help fine mapping of the underlying functional variants (28).We performed a comprehensive evaluation of the LD region of T2D loci reported in European and Asian GWAS in a meta-analysis of six AfA GWAS. By testing the index and nearby SNPs, we evaluated the transferability of the previously reported loci for T2D association in AfA. We demonstrated that the reduced and differential LD structure in AfA facilitated fine mapping of regions potentially harboring causal variants at some T2D loci.  相似文献   
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