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81.
Brachial plexus avulsion often results in massive motor neuron death and severe functional deficits of target muscles. However, no satisfactory treatment is currently available. Hypoxia-inducible factor 1α is a critical molecule targeting several genes associated with ischemia-hypoxia damage and angiogenesis. In this study, a rat model of brachial plexus avulsion-reimplantation was established, in which C5–7 ventral nerve roots were avulsed and only the C6 root reimplanted. Different implants were immediately injected using a microsyringe into the avulsion-reimplantation site of the C6 root post-brachial plexus avulsion. Rats were randomly divided into five groups: phosphate-buffered saline, negative control of lentivirus, hypoxia-inducible factor 1α(hypoxia-inducible factor 1α overexpression lentivirus), gel(pluronic F-127 hydrogel), and gel + hypoxia-inducible factor 1α(pluronic F-127 hydrogel + hypoxia-inducible factor 1α overexpression lentivirus). The Terzis grooming test was performed to assess recovery of motor function. Scores were higher in the hypoxia-inducible factor 1α and gel +hypoxia-inducible factor 1α groups(in particular the gel + hypoxia-inducible factor 1α group) compared with the phosphate-buffered saline group. Electrophysiology, fluorogold retrograde tracing, and immunofluorescent staining were further performed to investigate neural pathway reconstruction and changes of neurons, motor endplates, and angiogenesis. Compared with the phosphate-buffered saline group, action potential latency of musculocutaneous nerves was markedly shortened in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor1α groups. Meanwhile, the number of fluorogold-positive cells and ChAT-positive neurons, neovascular area(labeled by CD31 around av ulsed sites in ipsilateral spinal cord segments), and the number of motor endplates in biceps brachii(identified by α-bungarotoxin) were all visibly increased, as well as the morphology of motor endplate in biceps brachil was clear in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups. Taken together, delivery of hypoxia-inducible factor 1α overexpression lentiviral vectors mediated by pluronic F-127 effectively promotes spinal root regeneration and functional recovery post-brachial plexus avulsion. All animal procedures were approved by the Institutional Animal Care and Use Committee of Guangdong Medical University, China.  相似文献   
82.
83.
Background: Previous genome-wide association study (GWAS) has revealed the association between MYP10 at 8p23 and MYP15 at 10q21.1 and high myopia (HM) in a French population. This study is managed to discover the connection between some single nucleotide polymorphism (located at MYP10 and MYP15) and Han Chinese HM.

Methods and Results: This case-control association study contained 1673 samples, including 869 ophthalmic patients and 804 controls. Twelve tag SNPs have been selected from the MYP10 and MYP15 loci and genotyped by SNaPshot method. Among 12 SNPs, rs4840437 and rs6989782 in TNKS gene were found significant association with HM. Carriers of rs4840437G allele and rs4840437GG genotype created a low risk of high myopia (P = .036, OR = 0.81, 95%CI = 0.71–0.93; P = .016, OR = 0.73, 95%CI = 0.56–0.96; respectively). Carriers of rs6989782T allele and rs6989782TT+CT genotype also had a decreased risk of high myopia (P = .048, OR = 0.82, 95%CI = 0.71–0.94; P = .006, OR = 0.74, 95%CI = 0.59–0.92; respectively). Other 10 SNPs displaced nonsignificant association with HM. Additionally, the risk haplotype AC and the protective haplotype GT, generated by two SNPs in TNKS, were considerably more likely to be association with HM (for AC, P = .002 and OR = 1.26; for GT, P = .027 and OR = 0.84).

Conclusions: Our results demonstrated that some heritable variants in the TNKS gene are associated with HM in the Han population. The possible functions of TNKS in the development and pathogenesis of hereditary high myopia still require further researches to identify.  相似文献   

84.
Polycystic ovary syndrome (PCOS) is one of the most complex and common reproductive and endocrinologic disorders in the child-bearing age of women. Recently, miR-222 were reported to be associated with the etiology of PCOS. However, the function of miR-222 during the pathogenesis of PCOS remains unclear. In the present study, we aimed to investigate the role of miR-222 in PCOS. Firstly, miR-222 expression was examined by quantitative real-time PCR (qRT-PCR) in PCOS. The effects of miR-222 on proliferation, apoptosis and cell cycle in KGN cells were analyzed by CCK-8 assay and flow cytometry analysis, respectively. In addition, bioinformatics analysis was used to predict the target genes of miR-222, and dual-luciferase reporter assay was applied to verified the interaction between miR-222 and p27 Kip1 in KGN cells. Moreover, the expressions of p27 Kip1 in KGN cells treated with miR-222 mimics or miR-222 inhibitor were evaluated by qRT-PCR and western blot assays. The results showed that the expression of miR-222 was remarkably upregulated in PCOS tissues compared with corresponding normal tissues. In the gain-of-function and loss-of-function assays, we revealed that miR-222 mimics significantly promoted cell proliferation, while miR-222 inhibitor induced cell apoptosis and cell cycle arrested. Furthermore, p27 Kip1 was identified as a target gene of miR-222, and could be negatively regulated by miR-222 mimics in KGN cells. In conclusion, our findings suggested that miR-222 may promote the progression of PCOS by targeting p27 Kip1.  相似文献   
85.

Objective

The objective was to evaluate the pharmacokinetics (PKs) of levonorgestrel (LNG)-containing combined oral contraceptives (COCs) in obese women.

Study design

We pooled and reanalyzed data from 89 women with different body mass index (BMI) categories from four clinical studies. The LNG and ethinyl estradiol (EE) PKs were analyzed utilizing a zero-order absorption (K0), two-compartment PK model to evaluate key PK parameters in relation to a range of weights, BMI and body surface area (BSA).

Results

Increasing of body habitus metrics is correlated with decreasing Cmax (p<.0001) and AUCτ (p<.05) for both LNG and EE, but no correlation was found for Cmin (p≥.17). Increasing weight and BMI were associated with a modest increase (p≤.056) of clearance (CL) and appreciable increases of central volume (V1, p<.05), distribution clearance (CLd, p≤.001) and peripheral volume (V2, p<.0001) for LNG. For EE, increases in CL (p≤.009) were found with greater weight, BMI and BSA. Values of V1, CLd and V2 also increased (p<.0001) in obese subjects. The half-life and steady-state volume were greater among obese women (p<.0001) for both LNG and EE. LNG and EE PK parameters correlated well (p≤.006 for all), indicating that individual subject physiology affected both drugs similarly.

Conclusions

The primary effects of obesity on LNG and EE were a modest increase in CL and a marked increase in distribution parameters. We observed no obesity-related differences in trough LNG and EE concentrations.

Implications

This population PK analysis demonstrated reduced systemic exposure to LNG/EE oral contraceptives in obese subjects (Cmax and AUCτ); these particular differences are unlikely to lower contraceptive effectiveness among obese women who are correctly using LNG-containing contraceptives.  相似文献   
86.
Objective: To summarize the evidence from systematic reviews (SRs) on the benefits and safety of Tripterygium glycosides (TG) and total glucosides of paeony (TGP), commonly used to treat rheumatoid arthritis (RA) in China, for patients with RA. Methods: SRs of randomized controlled trials (RCTs) on TG or TGP in treating RA were included, by searching 8 databases from their inception until December 2017. Two authors extracted data independently. We assessed the quality of SRs using AMSTAR and graded the quality of evidence according to the GRADE approach. Results: Eleven SRs containing an average of 7.6 RCTs, involving a total of 7,012 participants were included in this overview. On the basis of included SRs, TG and TGP could improve the following indexes for RA patients: American College of Rheumatology (ACR) 20 response rate, ACR50 response rate and ACR70 response rate, swollen joint count, tender joint count, erythrocyte sedimentation rate and C-reactive protein. Moreover, TGP could reduce incidence of hepatotoxicity. The most common adverse effects of TG were gastrointestinal discomfort and gonad toxicity, while for TGP was mild to moderate diarrhea. The overall quality of evidence for these findings ranged from "low" to "moderate". Conclusions: TG and TGP might be 2 potentially effective complementary and alternative drugs for patients with RA. Nevertheless, due to gonad toxicity, TG should only be considered in elderly patients or patients without reproductive needs. More evidence from high quality RCTs and SRs is warranted to support the use of TG and TGP for RA patients.  相似文献   
87.
Intravenous leiomyomatosis (IVL) with intracardiac extension is a rare condition, which the benign tumor invades into the right heart through inferior vena cava. We described the findings of ultrasonography in eight patients with this disease. Transthoracic echocardiography (TTE) can reveal the intracardiac lesion burden and associated compromise. Contrast‐enhanced ultrasonography (CEUS) can trace the origin of the lesion and extension. Therefore, combining TTE with CEUS is used to better characterize this complex lesion and plays a crucial role in guidance of surgical decision.  相似文献   
88.
近视是世界范围内发病率最高的眼部疾病,且发病原因尚不明确,是全球关注的公共卫生问题。高度近视眼及其眼底并发症严重影响视功能。光学相干断层扫描血管成像(OCTA)技术是一种对视网膜、脉络膜自动精确分层,通过量化血流面积、无血流面积和血流密度区域,对视网膜、脉络膜多层面进行定性、定量的研究手段。应用OCTA,可对高度近视眼的发病机制从视网膜各层次微血管层面进行深入研究。笔者就高度近视眼底形态改变以及OCTA在评估高度近视眼底结构、功能及血流密度变化中的应用进行综述,期望为高度近视发病机制探究及干预提供指导。  相似文献   
89.
目的探讨人工弓状线切开技术在变异弓状线病例腹腔镜全腹膜外腹股沟疝修补术(TEP)应用的可靠性、安全性和有效性。 方法回顾性分析2016年7月至2019年8月广东医科大学茶山医院施行TEP的60例弓状线变异患者资料,在脐与耻骨联合连线中点人为切开腹直肌后鞘及其后面的腹横筋膜创建一条人工弓状线,并对其后面的腹膜前间隙进分离。影像记录弓状线的形态和手术步骤。 结果低位弓状线50例(83.3%),位于脐下8~12 cm,表现为不完整的腹直肌后鞘,向下呈逐渐变薄、变少的散在纤维。无弓状线10例(16.7%),有完整的腹直肌后鞘并一直延伸至耻骨。以人工弓状线为界分为两个层面,前面的是腹直肌后间隙,后面是腹膜前间隙,位于腹横筋膜(含有后鞘)与腹膜前筋膜浅层之间,是TEP理想的分离层面,沿此间隙向下分离与Retzius间隙相连,然后向外分离Bogros间隙。本组平均手术时间(130±15)min,术中腹膜损伤率8.3%(5/60)。术后发生血肿3例,血清肿2例,皮下气肿3例,无慢性疼痛病例。术后平均随访25个月,无复发病例。 结论人工弓状线切开技术在低位和无弓状线患者的TEP手术中安全有效、简单可靠,值得推广。  相似文献   
90.
目的探讨输尿管软镜碎石术和经皮超微肾镜碎石术治疗肾下盏结石疗效及安全性差异,为手术方案选择积累更多循证医学证据。方法选取本院2016年1月至2018年8月收治肾下盏结石患者136例,以随机抽签法分为对照组(68例)和观察组(68例),分别采用输尿管软镜碎石术和经皮超微肾镜碎石术治疗;比较两组术后3 d和28 d结石清除率、手术用时、术后疼痛评分、术后舒适度评分、术后住院时间、术后实验室指标水平及术后并发症发生率。结果观察组术后3 d和28 d结石清除率均显著高于对照组(P<0.05);观察组手术用时显著少于对照组(P<0.05);两组术后疼痛评分、舒适度评分及Hb下降值比较差异无统计学意义(P>0.05);观察组术后住院时间显著多于对照组(P<0.05);观察组术后WBC计数、PCT及hs-CRP水平显著低于对照组(P<0.05);同时两组术后发热和血尿发生率比较差异均无统计学意义(P>0.05)。结论经皮超微肾镜碎石术治疗肾下盏结石较输尿管软镜碎石术在提高结石清除效果和缩短手术用时方面具有优势,且可能降低术后继发炎症反应水平;而输尿管软镜碎石术应用则有助于加快术后康复进程。  相似文献   
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