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991.
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ  相似文献   
992.
Renal epidermal growth factor receptor (EGFR) signaling is activated in models of diabetic nephropathy (DN), and inhibition of the EGFR signaling pathway protects against the development of DN. We have now determined that in cultured podocytes, high glucose led to increases in activation of EGFR signaling but decreases in autophagy activity as indicated by decreased beclin-1 and inhibition of LC3B autophagosome formation as well as increased rubicon (an autophagy inhibitor) and SQSTM1 (autophagy substrate). Either genetic (small interfering [si]EGFR) or pharmacologic (AG1478) inhibition of EGFR signaling attenuated the decreased autophagy activity. In addition, rubicon siRNA knockdown prevented high glucose–induced inhibition of autophagy in podocytes. We further examined whether selective EGFR deletion in podocytes affected the progression of DN in type 2 diabetes. Selective podocyte EGFR deletion had no effect on body weight or fasting blood sugars in either db/db mice or nos3−/−; db/db mice, a model of accelerated type 2 DN. However selective podocyte EGFR deletion led to relative podocyte preservation and marked reduction in albuminuria and glomerulosclerosis, renal proinflammatory cytokine/chemokine expression, and decreased profibrotic and fibrotic components in nos3−/−; db/db mice. Podocyte EGFR deletion led to decreased podocyte expression of rubicon, in association with increased podocyte autophagy activity. Therefore, activation of EGFR signaling in podocytes contributes to progression of DN at least in part by increasing rubicon expression, leading to subsequent autophagy inhibition and podocyte injury.  相似文献   
993.
BackgroundWork-related musculoskeletal injuries have been increasingly recognized to affect surgeons. It is unknown whether such injuries also affect surgical trainees. The purpose of this study was to assess the ergonomic risk of surgical trainees as compared with that of experienced surgeons.MethodsErgonomic data were recorded from 9 surgeons and 11 trainees. Biomechanical loads during surgery were assessed using motion tracking sensors and electromyography sensors. Demanding and static positions of the trunk, neck, right/left shoulder, as well as activity from the deltoid and trapezius muscles bilaterally were recorded. In addition, participants reported their perceived discomfort on validated questionnaires.ResultsA total of 87 laparoscopic general surgery cases (48 attendings and 39 trainees) were observed. Both trainees and attendings spent a similarly high percentage of each case in static (>60%) and demanding positions (>5%). Even though residents reported overall more discomfort, all participants shared similar ergonomic risk with the exception of trainees’ trunk being more static (odds ratio: –11.42, P = .006).ConclusionSurgeons are prone to ergonomic risk. Trainees are exposed to similar postural ergonomic risk as surgeons but report more discomfort and, given that musculoskeletal injuries are cumulative over time, the focus should be on interventions to reduce ergonomic risk in the operating room.  相似文献   
994.
Objective To examine the protective effects of hydroxysafflor yellow A (HSYA) against the senescence of mesenchymal stem cells (MSCs) induced by D-galactose (D-gal) in vitro, and investigate the potential mechanism involved. Methods Grouping experiment, Normal control (NC) group: conventional culture with complete medium; Senescence group: MSCs were cultured for 48 h with complete medium containing 10 g/L D-gal; HSYA group: on the basis of senescence induction, HSYA with the suitable concentration was used to protect MSCs. The key experimental indices associated with oxidative stress, inflammatory response, cell senescence, proliferation and apoptosis were measured through chemical colorimetry, β-galactosidase staining, EdU incorporation and flow cytometry, respectively. The relative quantity (RQ) of proteins related closely to cell proliferation, apoptosis, and NF-κB signaling were measured by Western blotting. Results As compared with Senescence group, treatment with HSYA (120 mg/L) effectively ameliorated the adverse situation of MSCs. Oxidation stress and inflammation along with D-Gal induction was dramatically alleviated in MSCs; The β-Gal-positive staining indicated that MSC senescence was significantly mitigated; The proliferative capability of MSCs was significantly increased by up-regulating PCNA and inhibiting p16 expression; The anti-apoptotic effect on MSCs was exerted by down-regulating the RQ of cleaved Caspase-3 and Bax; The activity of NF-κB signaling in MSCs was notably suppressed through inhibiting phosphorylation of IKKβ and p65. Conclusion HSYA (120 mg/L) significantly delayed the D-Gal-induced senescence process in MSCs through attenuating inflammatory reaction and oxidative stress, and suppressing the activity of NF-κB signaling.  相似文献   
995.
Objective: To establish a method for directional screening of the cytotoxic components from the medicinal herb of Achnatherum inebrians by a combination of surface plasmon resonance (SPR) biosensor and chromatographic isolation technology. Methods: Under the guidance of bioactive assessment based on binding abilities between objects and the α-Mannosidase (α-Man) target, the active components from different solvents extracts, different polar extraction parts and fractions were screened orderly and directionally using SPR. Components with a high binding ability to α-Man can be precisely oriented in a narrower fractions range and are easy to isolate. Three human cancer cells were used to evaluate the cytotoxic activity of component with the highest affinity to α-Man. Results: Eight compounds were isolated and identificated from A. inebrians for the first time. Deoxyvasicinone possessed the highest affinity to α-Man among them. Moreover, deoxyvasicinone showed good effects on inhibited proliferation of human hepatoma cells HepG2 (IC50 = 5.7 μmol/L), human breast cancer cells MCF7 (IC50 = 7.21 μmol/L) and human lung cancer cells HCC827 (IC50 = 0.75 μmol/L), respectively. In particular, its inhibitory effect on HCC827 was stronger than the positive drug gefitinib (IC50 = 1.65 μmol/L). Conclusion: A comprehensive strategy of directional screening potential cytotoxic components from herb based on biomolecular interaction and chromatography was established. Deoxyvasicinone as an effective anti-cancer component was initially isolated from A. inebrians. It is expected that this screening strategy could provide new perspectives for rapid screening and identification of active components from natural plants with the complex matrix.  相似文献   
996.
张瑜  杜晨晖  詹海仙  尚彩玲  李瑞锋  原淑佳 《中草药》2023,54(15):4981-4991
目的 以桔梗Platycodon grandiflorus为材料,分析其叶绿体基因组特征,探究不同地区桔梗叶绿体基因组的差异及桔梗科其他物种的系统发育关系。方法 利用Illumina NovaSeq测序平台对桔梗叶绿体全基因组进行测序,完成其组装、注释和特征分析,采用生物信息学方法对不同地区桔梗进行比较基因组分析和系统发育分析。结果 桔梗叶绿体基因组全长172 770 bp,呈现典型的环状四分体结构,总GC含量为38.10%,注释到139个基因,其中蛋白质编码基因95个,核糖体RNA 8个和转运RNA 36个。经序列分析鉴定出139个SSR位点,大部分重复由A和T组成。该叶绿体基因组密码子偏好性A/U大于G/C。边界分析表明,不同地区桔梗的JLA边界区域存在差异。对比不同地区桔梗叶绿体基因组序列发现21个变异区间,包括ycf1psbCrps18rpoB等编码区以及rpl32-trnLtrnS-psbZtrnN-ycf1等非编码区。基于最大似然法(maximum likelihood method,ML)对桔梗及其他17种桔梗科植物进行系统发育分析,发现桔梗科物种形成一个单系群,各属物种聚为一束,支持率达100%。结论 桔梗科物种聚为一支与传统相符合,不同地区桔梗叶绿体基因组序列存在显著差异,为后期开展分子鉴定及群体遗传学研究提供提供科学依据。  相似文献   
997.
感染性发热归属于中医学火热证范畴,火热证的病机大多为阳气怫郁、阻遏于内,这种因郁而作的发热,称为火郁证。运用五辨(辨病、辨症、辨证、辨人、辨机)思维辨识火郁证,对火郁证的发病特点及规律进行概括,可把握火郁证的内在发病机制,有助于全面而深刻地理解感染性发热。  相似文献   
998.
术后肺部并发症(PPCs)是影响患者围术期预后的主要原因,需要麻醉科医师重点关注并有效防治。越来越多的证据表明,围术期实行肺保护策略可减少PPCs。近5年来,围术期肺保护策略研究已成为围术期医学关注的重点问题之一,围术期肺保护是加速康复外科的重要组成部分,其策略包括术前风险预测、术中肺保护性通气、术后镇痛及物理治疗等。本综述结合围术期肺保护策略最新进展进行阐述,以提高麻醉科医师对PPCs潜在风险的认识,为制定围术期个体化肺保护方案提供策略。未来还应进一步研究以阐明围术期肺保护策略对患者预后结局的影响。  相似文献   
999.
1000.
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