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991.
目的 研究从海洋蓝藻 Okeania hirsute 中分离鉴定次级代谢产物并进行细胞毒活性评价。方法 三个天然产物(1~3)的结构确定是通过广泛的波谱数据,包括一维和二维核磁及质谱等。结果 化合物3对人大细胞肺癌细胞NCI-H460显示出强的细胞毒活性,IC50值为0.384 μg/mL。结论 这是首次从Okeania属蓝细菌中分离获得化合物1~3。这些天然产物的发现表明Okeania属蓝细菌可以作为发现新颖化合物的重要来源。  相似文献   
992.
Pro-anorexic websites are a popular online venue for individuals with anorexia, but recent research suggests that they play a role of “online negative enabling support groups” because they can undermine recovery and encourage negative behaviors by validating pro-anorexic views. By analyzing 22,811 messages from 5,590 conversations from the Pro-Ana Nation online discussion board forum, this study examines communicative mechanisms of online negative enabling support through language analysis of disclosure-response sequences, changes in the language of the initial discloser within an interaction exchange, and the role of responses in eliciting those changes. The findings show that initiating disclosures containing stigma-related emotion words, anorexia-specific content, and sociorelational content are typically met with negatively valenced responses from other members of the pro-anorexic community. Moreover, although the act of revealing stigmatized information has some cathartic effects, disclosers use more, not fewer, stigma-related emotion words when they receive negatively valenced responses. These results provide insight into communicative dynamics and effects of online negative enabling support through validation of the pro-anorexic identity and the dangerous cycle of stigma escalation in disclosure-response exchanges on pro-anorexic online communities.  相似文献   
993.
目的 通过比较新辅助放化疗后cCR的直肠癌患者采用非手术治疗和TME治疗的效果,旨在探讨非手术治疗策略的可行性。方法 选取2006—2016年中山大学肿瘤防治中心接受术前放化疗并获得cCR的135例Ⅱ、Ⅲ期直肠癌患者,根据治疗方法的不同将其分为非手术组(43例NOM组)和标准手术组(92例SOM组)。比较2组患者的局部复发率、挽救性治疗后的累计LC率、DFS、OS以及保肛率等。Kaplan-Meier法计算LC、OS、DFS并Logrank法检验,χ2检验保肛率。结果 中位随访39个月(10~127个月)。135例患者的局部复发率及远处转移率分别为3.7%和11.1%,术后3年DFS和OS分别为90.5%和97.0%。NOM组与SOM组术后3、5年DFS率分别为87%与93%、73%与87%(P=0.089),OS率分别为98%与99%、98%与97%(P=0.578)。NOM组局部复发5例(12%),80%患者得到挽救性治疗,累计LC率为98%;SOM组无局部复发病例;两组差异有统计学意义(P=0.010)。NOM组保肛率为93%,显著高于SOM组的70%(P=0.030)。结论 新辅助放化疗后获得cCR的直肠癌患者采取非手术治疗策略是可行的,部分局部复发患者仍可通过及时的挽救性治疗痊愈,从而有效避免了TME及其并发症,提高了患者的生活质量。  相似文献   
994.
目的:评价激痛点神经阻滞联合针刀治疗冈上肌腱炎的临床疗效。方法:63例患者随机分为"神经阻滞组"32例和"神经阻滞联合针刀组"31例,共2组。取穴:肱骨大结节激痛点和冈上窝激痛点。神经阻滞组于激痛点注射消炎镇痛液;神经阻滞联合针刀组注射消炎镇痛液后,行针刀治疗。1次/周,共3次,3周后随访。结果:2种疗法均能降低VAS评分,提高C-M分值(P0.05)。神经阻滞联合针刀组治疗后VAS=(23.39±22.30)分,C-M=(81.06±15.83)分,优于神经阻滞组(P0.01)。结论:神经阻滞联合针刀组冈上肌腱炎疗效显著。  相似文献   
995.
We screened a midgut cDNA library from diamondback moth, Plutella xylostella, with a probe generated using sequence information from an aminopeptidase N gene from Manduca sexta (MsAPN-1). The sequence recovered (PxAPN-A) encodes a protein of 988 resides with a 60% sequence identity to MsAPN-1. The two proteins share a signal peptide which directs processing by the endoplasmic reticulum, a C-terminal hydrophobic region satisfying the criterion for a GPI anchor and cleavage, and the possibility of an O-glycosylated rigid stalk attached to the GPI anchor. PxAPN-A is more closely related to MsAPN-1 than it is to another aminopeptidase recently reported from P. xylostella. Sequence comparisons with other species suggests that at least one aminopeptidase gene duplication occurred in an ancestral lepidopteran.  相似文献   
996.
背景:研究表明胰岛素样生长因子1具有神经保护作用并能增加神经干细胞向神经元及少突胶质细胞分化的比例。目的:观察胰岛素样生长因子1对神经干细胞源性神经元轴突生长发育的影响。方法:分离培养新生Wistar大鼠海马神经干细胞,传3~5代后接种于24孔培养板。其中12孔加入10μL胰岛素样生长因子1(500mg/L)作为实验组,余为对照组。结果与结论:培养1,2,3,4d时,实验组细胞死亡数较对照组明显减少(P<0.05),神经元轴突长度较对照组明显延长(P<0.05),但两组轴突的分叉数目差异无显著性意义(P>0.05)。结果证实胰岛素样生长因子1可以增加神经干细胞向神经元的分化比例并促进神经干细胞源性神经元轴突长度的延伸,但不能增加轴突的分叉数量。  相似文献   
997.
Many major weeds rely upon vegetative dispersal by rhizomes and seed dispersal by "shattering" of the mature inflorescence. We report molecular analysis of these traits in a cross between cultivated and wild species of Sorghum that are the probable progenitors of the major weed "johnsongrass." By restriction fragment length polymorphism mapping, variation in the number of rhizomes producing above-ground shoots was associated with three quantitative trait loci (QTLs). Variation in regrowth (ratooning) after overwintering was associated with QTLs accounting for additional rhizomatous growth and with QTLs influencing tillering. Vegetative buds that become rhizomes are similar to those that become tillers--one QTL appears to influence the number of such vegetative buds available, and additional independent genes determine whether individual buds differentiate into tillers or rhizomes. DNA markers described herein facilitate cloning of genes associated with weediness, comparative study of rhizomatousness in other Poaceae, and assessment of gene flow between cultivated and weedy sorghums--a risk that constrains improvement of sorghum through biotechnology. Cloning of "weediness" genes may create opportunities for plant growth regulation, in suppressing propagation of weeds and enhancing productivity of major forage, turf, and "ratoon" crops.  相似文献   
998.
Li  Chengzong  Ju  Weizhu  Gu  Kai  Li  Mingfang  Cui  Chang  Liu  Hailei  Wang  Zidun  Chen  Hongwu  Yang  Gang  Zhang  Fengxiang  Yang  Bing  Wang  Zhirong  Chen  Minglong 《Journal of interventional cardiac electrophysiology》2021,60(3):365-373
Purpose

Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.

Methods

Eighteen SND patients (53.3?±?9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.

Results

Compared with controls, SND patients showed significant PWA reduction (0.13?±?0.02 vs. 0.16?±?0.04 mV, p?=?0.017) and PWD prolongation (120.8?±?15.2 vs. 105.2?±?8.6 ms, p?=?0.001). The RA endocardial voltage was lower (1.56?±?0.78 vs. 2.57?±?0.55 mV, p?<?0.001) and activation time was longer (112.1?±?14.9 vs. 90.8?±?12.4 ms, p?<?0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57–88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44?±?1.16 vs. 1.87?±?1.01 mV, p?=?0.003).

Conclusions

Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing.

  相似文献   
999.
Background & aimsSarcopenia is a clinical syndrome that features muscle atrophy and weakness, and has been associated with cardiovascular events and poor clinical outcomes. Recently, the sarcopenia index (SI) was developed as a simple screening tool based upon the serum creatinine to cystatin C (CysC) ratio. We investigated the association between SI and the prevalence of major adverse cardiovascular events (MACE) in patients with obstructive CAD.Methods & ResultsBetween January 2010 and December 2018, patients with angina pectoris and obstructive CAD requiring coronary artery intervention were enrolled. Serum levels of CysC and other biomarkers were assessed. Patients were divided into two groups according to the SI ([Cr/CysC] x 100). Demographic characteristics and clinical outcomes of the two groups were evaluated. A total of 427 patients (79.6% men, mean age 69.55 ± 12.04 years) were enrolled. Patients with SI < 120 (n = 214, 28%) were older, more likely to be of the female gender, and to have more hypertension and congestive heart failure (all p < 0.05). The prevalence of major adverse cardiovascular events (MACE) composed of myocardial infarction, stroke, and all-cause mortality was higher in patients with lower SI (p = 0.026). After adjusting for potential confounding factors, multivariate Cox regression (hazard ratio 2.08, p = 0.045) and Kaplan–Meier analyses (log-rank p = 0.0371) revealed that lower SI was significantly associated with a higher prevalence of MACE.ConclusionsSerum creatinine to cystatin C ratio (SI) may be a useful surrogate marker to predict the future prevalence of MACE in patients with obstructive CAD.  相似文献   
1000.
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