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41.
目的通过轴向应力刺激促进骨再生,观察基质细胞衍生因子 1α/趋化因子 CXC 亚族受体 4(stromal cell-derived factor 1α/cysteine X cysteine receptor 4,SDF-1α/CXCR4)信号通路变化,探讨轴向应力刺激促进骨再生的机制。方法取 72 只雄性新西兰大白兔,于右后肢胫骨近端内侧制备直径 8 mm 圆形皮质骨缺损并脱蛋白松质骨支架修复模型,随机分为 3 组(n=24)。A 组腹腔注射 PBS,B 组术肢给予应力刺激治疗+腹腔注射 PBS,C 组术肢给予应力刺激治疗+腹腔注射 CXCR4 拮抗剂(AMD3100)。术后 2、4、8、12 周,摄 X 线片并采用 Lane-Sandhu X 线评分标准评价骨愈合情况,取标本行 HE 染色观察新生骨组织及支架降解,免疫组织化学染色观察 VEGF、CXCR4 表达水平;4、8 周取标本 Western blot 检测 SDF-1α 及 CXCR4 蛋白表达水平;12 周行 Micro-CT 检查,计算新生骨体积及新生骨密度。 结果X 线片检查示,除术后 2 周各组骨缺损区及支架无明显变化外,4、8 及 12 周时 B 组骨愈合评分均高于 A、C 组(P<0.05)。12 周时 Micro-CT 扫描可见 B 组骨缺损修复、髓腔再通,新生骨体积及骨密度均高于 A、C 组(P<0.05)。HE 染色显示,术后 4 周开始 B 组骨再生及支架降解均明显快于 A、C 组。免疫组织化学染色示,各组 VEGF 及 CXCR4 阳性表达均在 4 周达峰值;各时间点 B 组 VEGF 及 CXCR4 表达量均显著高于 A、C 组(P<0.05)。Western blot 检测显示,4、8 周时 B 组 SDF-1α 与 CXCR4 表达量均显著高于 A、C 组(P<0.05)。 结论轴向应力刺激促进骨再生可能与其促进骨缺损区组织高表达 SDF-1α,激活与其下游调控 BMSCs 募集的 CXCR4 信号有关。  相似文献   
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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   
44.
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   
45.
目的总结近年来股骨转子间骨折在稳定性重建方面的概念演化与研究进展。方法查阅国内外相关文献并结合自身经验,从股骨转子间骨折的解剖特点、稳定型骨折与不稳定型骨折分类、稳定性复位与不稳定性复位、术中加压初始稳定与术后滑动二次稳定、内固定术后稳定性评估、早期下地站立负重等方面进行总结分析。结果股骨转子间骨折发生于股骨颈干骺端转换区,具有天然的内翻不稳定倾向。骨折复位质量是影响后续内固定物安放的最重要前提因素。判断骨折复位质量有对线和对位两方面,对线采用 Garden 指数;在对位方面,随着皮质对位理念(正性、中性、负性)的提出,特别强调前内侧皮质的相互砥住支撑(解剖、正性),是获得骨折稳定性复位的关键,而不再强调后内侧小转子骨块的作用。术后影像学的稳定性评分为早期下地站立负重提供了量化指标。但术中的前内侧皮质支撑复位,在术后头颈骨块滑动获得二次稳定的过程中,仍有皮质对位丢失现象,需研究其危险因素和防范措施。结论股骨转子间骨折在取得良好对线的基础上,只要获得了前内侧皮质的相互砥住和支撑,并用内固定器械维持住,就获得了术后稳定性。术后稳定性评分优良者,可以安全地早期下地负重、站立行走活动。  相似文献   
46.
《Vaccine》2022,40(19):2679-2695
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.ObjectiveA systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.MethodsThe protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.ResultsWe retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found. Efficacy: limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration. Safety: vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).ConclusionsMore evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population.  相似文献   
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48.
PurposeTo assess the prediction of the response to photodynamic therapy (PDT) in chronic central serous chorioretinopathy (CSCR) based on spectral-domain optical coherence tomography (SD-OCT) images using deep learning (DL).MethodsRetrospective study including 216 eyes of 175 patients with CSCR and persistent subretinal fluid (SRF) who underwent half-fluence PDT. SD-OCT macular examination was performed before (baseline) and 3 months after treatment. Patients were classified into groups by experts based on the response to PDT: Group 1, complete SRF resorption (n = 100); Group 2, partial SRF resorption (n = 66); and Group 3, absence of any SRF resorption (n = 50). This work proposes different computational approaches: 1st approach compares all groups; 2nd compares groups 1 vs. 2 and 3 together; 3rd compares groups 2 vs. 3.ResultsThe mean age was 55.6 ± 10.9 years and 70.3% were males. In the first approach, the algorithm showed a precision of up to 57% to detect the response to treatment in group 1 based on the initial scan, with a mean average accuracy of 0.529 ± 0.035. In the second model, the mean accuracy was higher (0.670 ± 0.046). In the third approach, the algorithm showed a precision of 0.74 ± 0.12 to detect the response to treatment in group 2 (partial SRF resolution) and 0.69 ± 0.15 in group 3 (absence of SRF resolution).ConclusionDespite the high clinical variability in the response of chronic CSCR to PDT, this DL algorithm offers an objective and promising tool to predict the response to PDT treatment in clinical practice.  相似文献   
49.
BackgroundMenopausal symptoms have negative effects on the aspects of quality of life and impose a high cost on the health system. In traditional Persian medicine, pomegranate is recommended to alleviate menopausal symptoms.Material and methodsA randomized double-blind placebo-controlled trial was performed among 78 healthy women. Participants were interviewed three times: Before receiving the supplement/placebo, after completing the treatment, and after 3 weeks with no intervention. They filled out the demographic information sheet, modified-Kupperman index, and Menopause-Specific Quality of Life (MENQOL) questionnaires.ResultsThe mean scores of the modified-Kupperman index and MENQOL characteristics before and after the treatment and after the follow-up period were significantly different between pomegranate and placebo groups in both modified-Kupperman and MENQOL scores (p < 0.001).ConclusionThis study demonstrated that 4 weeks' treatment with the pomegranate supplement significantly ameliorates the irritating symptoms of menopause and improves the quality of life in menopausal women even after 4 weeks' medicine deprivation.  相似文献   
50.
PurposeHirschsprung Disease (HD) is a common congenital intestinal disorder. While aganglionosis most commonly affects the rectosigmoid colon (rectosigmoid HD), outcomes for patients in which aganglionosis extends to more proximal segments (long-segment HD) remain understudied. This study sought to compare postoperative outcomes among newborns with rectosigmoid and long-segment HD.MethodsThe Nationwide Readmission Database was queried from 2016 to 2018 for newborns with HD. Newborns were stratified into those with rectosigmoid or long-segment HD. Those who received no rectal biopsy or pull-through procedure during their newborn hospitalization were excluded. A propensity score-matched analysis (PSMA) of newborns with either type of HD was constructed utilizing 17 covariates including demographics, comorbidities, and congenital-perinatal conditions.ResultsThere were 1280 newborns identified with HD (82% rectosigmoid HD, 18% long-segment HD). Patients with rectosigmoid HD had higher rates of laparoscopic resections (35% vs. 12%) and less frequently received a concomitant ostomy (14% vs. 84%), both p < 0.001. Patients with long-segment HD were more likely to have a delayed diagnosis (12% vs. 5%) and require multiple bowel operations (19% vs. 4%), both p < 0.001. They experienced higher rates of complications, including small bowel obstructions (10% vs. 1%), infections (45% vs. 20%), and Hirschsprung-associated enterocolitis (11% vs. 5%), all p < 0.001. After PSMA, newborns with long-segment HD were found to have a longer length of stay and higher hospitalization costs.ConclusionNewborns with long-segment HD experience significant delays in diagnosis, surgery, and complications compared to those with rectosigmoid HD. This information should be utilized to improve healthcare delivery for this patient population.Type of StudyRetrospective comparative study.Level of EvidenceIII.  相似文献   
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