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31.
Alcohol consumption is considered to be the third leading cause of death in the United States. In addition to its direct toxicity, ethanol has two contrasting effects on the immune system: the nucleotide oligomerization domain‐like receptor pyrin domain‐containing‐3 (NLRP3) inflammasome is inhibited by acute ethanol exposure but activated by chronic ethanol exposure. Purinergic receptors (especially the P2X7 receptor) are able to activate the NLRP3 inflammasome and are involved in many ethanol‐related diseases (such as gout, pulmonary fibrosis, alcoholic steatohepatitis, and certain cancers). We hypothesized that ethanol regulates purinergic receptors and thus modulates the NLRP3 inflammasome's activity. In experiments with monocyte‐derived macrophages, we found that interleukin (IL)‐1β secretion was inhibited after 7 h of exposure (but not 48 h of exposure) to ethanol. The disappearance of ethanol's inhibitory effect on IL‐1β secretion after 48 h was not mediated by the upregulated production of IL‐1β, IL‐1α, IL‐6 or the inflammasome components NLRP3, apoptosis‐associated speck‐like protein containing a caspase recruitment domain, and caspase 1. P2X7R expression was upregulated by ethanol, whereas expression of the P2X4 and P2X1 receptors was not. Taken as a whole, our results suggest that ethanol induces NLRP3 inflammasome activation by upregulating the P2X7 receptor. This observation might have revealed a new mechanism for inflammation in ethanol‐related diseases.  相似文献   
32.

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Objectives

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

Methods

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

Results

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

Conclusions

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.  相似文献   
33.
目的 探讨胶质瘤中MKK7和c-Jun磷酸化(p-c-Jun)的表达及意义,分析两者表达的相关性。方法 选取弥漫型星形细胞瘤(15例)、少突胶质细胞瘤(5例)、间变性星形细胞瘤(11例)、间变性少突胶质细胞瘤(8例)、胶质母细胞瘤(53例)及其瘤旁正常脑组织(25例)共117例,采用免疫组织化学法检测MKK7、c-Jun及p-c-Jun的表达。体外培养神经胶质瘤细胞株U87,用脂质体转染MKK4-siRNA、MKK7-siRNA和对照siRNA,48 h后Western blot检测MKK7、c-Jun及p-c-Jun的表达水平。结果 胶质母细胞瘤中p-c-Jun及MKK7的表达均明显高于其他组织学类型胶质瘤及胶质母细胞瘤瘤旁正常脑组织中的表达(P=0.000, P=0.000)。随着胶质瘤WHO分级的升高,p-c-Jun及MKK7的表达增高,且与WHO分级呈明显正相关(r=0.494, P=0.000; r=0.606, P=0.000)。胶质瘤及胶质母细胞瘤瘤旁正常脑组织中MKK7与p-c-Jun的表达存在正相关关系(r=0.387, P=0.000)。沉默神经胶质瘤细胞株U87 MKK7表达抑制了c-Jun磷酸化水平。结论 MKK7可以通过调控JNK/c-Jun活性进而促进胶质母细胞瘤的发生。  相似文献   
34.
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism.  相似文献   
35.

Introduction

Adequate perfusion and oxygenation to liver graft after transplantation is essential for its viability. Hepatic oximetry (hepatic tissue oxygenation [LSrO2]) through near infrared spectroscopy (NIRS) can help by showing real time oxygen content of the graft.

Methods

In this prospective study, we enrolled 50 consecutive patients undergoing liver transplant surgery from deceased donors.Liver NIRS (LSrO2) was continuously measured for 24 hours then analyzed and correlated with other clinical data such as hemoglobin (Hb), mixed venous oxygen saturation, cardiac index (CI), central venous pressure, arterial gases, diuresis, blood lactate, liver biochemistry, and normalized index ratio (INR). Severity disease scales and cold-warm ischemia time were also measured, as well as Doppler ultrasound (DUS) at hour 24. A statistical analysis with IBM SPSS 22 using Pearson correlation was carried out.

Results

LSrO2 could anticipate serious bleeding and hemodynamic events showing a decrease >10% from basal data.We found a significant correlation between LSrO2 with CI at 3 hours (P=.044), hemoglobin (Hb) at hour 3 and 24 (P = .004 and P = .002, respectively), and with Apache II (P=.041).A significant correlation was also detected between cold ischemia and INR at hour 24 (P=.016).No correlation of LSrO2 was found with lactate, liver biochemistry, and DUS data.  相似文献   
36.
BackgroundDespite proposals and guidelines to prevent baseball injuries in young players by societies and organizations, many shoulder and elbow injuries continue to occur among junior high school baseball players. In order to investigate the training conditions of junior high school baseball players and the risk factors for shoulder and elbow pain in the players, we conducted a questionnaire survey among junior high school baseball players throughout the country.MethodsThe questionnaire survey was conducted among junior high school baseball players in September 2016.ResultsA total of 11,134 junior high school baseball players belonging to 495 teams responded to the survey. Among these, 4004 players trained every day of the week and 1151 players played baseball games every month with no off-season. Among 9752 players who did not have shoulder and/or elbow pain in the spring and summer of 2015, 19.2% of players experienced elbow pain over the course of one year, 13.6% of players experienced shoulder pain, and 28.0% complained of shoulder and/or elbow pain. The frequency of elbow pain was more than that of shoulder pain. At risk for shoulder pain were pitchers and catchers and second-year students, while risk factors for elbow pain were playing pitcher and catcher positions, pitching or throwing ≥300 balls per week, playing ≥10 games on average per month and being left-handed.ConclusionRisk factors for shoulder pain were different from those for elbow pain. To prevent elbow pain, coaches should pay attention to pitchers and catchers and left-handed players and not allow players to pitch or throw ≥300 full-power balls per week or participate in ≥10 games per month. They should also pay attention to pitchers and catchers and second-year students to prevent shoulder pain. It is important for coaches to train multiple pitchers and catchers.  相似文献   
37.
Generalized pustular psoriasis (GPP) is now known to be caused by biallelic variants in IL36RN and monoallelic variants in CARD14 and AP1S3. The presence of a modifier locus or oligogenic inheritance have been hypothesized. We report on a patient with a unique coinheritance of pathogenic variants in IL36RN (c.115+6T>C) and TNFAIP3 (c.547C>T, p.R183 * ) causing the genetic entities GPP and familial Behçet‐like autoinflammatory syndrome (AISBL). The heterozygous variant in IL36RN identified by Sanger sequencing was inherited from his unaffected father, while the heterozygous variant in TNFAIP3 was detected by whole‐exome sequencing and was also identified in the patient's AISBL‐affected maternal relatives. Further functional studies are required to research whether the variant of TNFAIP3 plays a part in the development of GPP or simply causes the Behçet's disease phenotype. However, our data suggest that whole‐exome sequencing for the heterozygous carrier of the IL36RN gene in GPP be used to find the potential second genetic locus.  相似文献   
38.
目的评估淫羊藿苷对低浓度糖皮质激素诱导的骨微血管内皮细胞(bone microvascular endothelial cells,BMECs)自噬和外泌体分泌的影响。方法从行全髋关节置换术切取的股骨头中分离 BMECs,用一系列低浓度梯度氢化可的松(0、0.03、0.06、0.10 mg/mL)干预(设为 A、B、C、D 组),在此基础上再用 5×10−5 mol/L 淫羊藿苷干预(设为 A1、B1、C1、D1 组),24 h 后采用 Western blot 检测自噬相关蛋白微管相关蛋白轻链 3B(microtubule-associated protein 1 light chain 3B,LC3B)及死骨片 1(p62)的表达。从经淫羊藿苷处理(干预组)和未经淫羊藿苷处理(未干预组)的 BMECs 中提取外泌体,纳米颗粒跟踪分析技术检测其直径和浓度,BCA 法检测外泌体总蛋白质含量,Western blot 检测外泌体 CD9、CD81、TGF-β1 和 VEGFA 蛋白的表达。进一步将 BMECs 分为 3 组,实验组和对照组分别分离经或未经淫羊藿苷处理的 BMECs 分泌的外泌体,与 BMECs 共培养;空白对照组为单纯 BMECs。氢化可的松处理后,采用 Western blot 检测 LC3B 和 p62 表达,划痕实验检测细胞迁移能力,并观察血管生成能力。 结果随氢化可的松浓度升高,各组 LC3B-Ⅱ蛋白相对表达量逐渐增加,p62 蛋白相对表达量减少,各组间差异均有统计学意义(P<0.01);相同激素浓度下,淫羊藿苷干预后,LC3B-Ⅱ蛋白相对表达量减少,p62 蛋白相对表达量增加(P<0.01)。干预组外泌体浓度显著高于未干预组(t=−10.191,P=0.001);两组外泌体直径和总蛋白质含量比较差异均无统计学意义(P>0.05)。未干预组和干预组 CD9 和 CD81 蛋白均高度表达;干预组 VEGFA/CD9 和 TGF-β1/CD9 蛋白相对表达量比值均显著高于未干预组(P<0.01)。外泌体共培养后,空白对照组、对照组和实验组中 p62 蛋白相对表达量呈递增趋势,LC3B-Ⅱ蛋白相对表达量呈递减趋势,各组间比较差异均有统计学意义(P<0.05)。氢化可的松处理 12、24 h 时,对照组和实验组划痕闭合率明显高于空白对照组(P<0.05),实验组明显高于对照组(P<0.05);氢化可的松处理 4、8 h 时,实验组和对照组管腔数、出芽数和小管分支长度均显著大于空白对照组(P<0.05);实验组小管分支长度和管腔数显著大于对照组(P<0.05)。 结论淫羊藿苷及 BMECs 产生的外泌体能改善低浓度激素诱导的 BMECs 自噬,对内皮细胞起到保护作用。  相似文献   
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