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41.
From the aerial parts of THYMUS PIPERELLA, the free flavone aglycones 5,6-dihydroxy-7,8,4'-trimethoxyflavone ( 1), 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone ( 2), 5,6-dihydroxy-7,3',4'-trimethoxyflavone ( 3), ladanein ( 4) (5,6-dihydroxy-7,4'-dimethoxy-flavone), 5-hydroxy-7,4'-dimethoxyflavone ( 5) and apigenin ( 6), the flavanones naringenin ( 7) and eriodictyol ( 8), and the flavone glycosides vicenin-2 ( 9), apigenin-7- O-beta- D-glucoside (10) and luteolin-7- O-beta- D-glucoside ( 11), have been isolated and identified. This is the first time that 5,6-dihydroxy-7,8,4'-trimethoxyflavone has been found as a natural product.  相似文献   
42.
The hypothesis proposed in this study was that the initiation of active and passive knee motion within 48 hours of major intraarticular knee ligament surgery would not have the deleterious effects of increasing knee effusion, hemarthrosis, periarticular soft tissue edema, and swelling. We conducted a prospective study with randomized assignment of 18 patients into two groups: 9 patients in the "motion" group began 10 hours of daily continuous passive motion (CPM) on the 2nd postoperative day, while the remaining 9 in the "delayed motion" group used a soft hinged knee brace with knee hinges locked at 10 degrees of flexion and entered into the motion program on the 7th postoperative day. All knees were allowed full 0 degrees to 90 degrees of motion except for a total of seven knees with concomitant mensicus repairs and extraarticular reconstructions where 20 degrees to 90 degrees of motion was allowed, limiting the last 20 degrees of knee extension for the first 4 postoperative weeks to protect the repair. In all other respects, the rehabilitation program after surgery was the same for the two groups, including postoperative compression dressings, exercises, and weight-bearing status. Ten of the eighteen patients had acute ACL disruptions and 8 had chronic ACL insufficiencies. There was an even distribution of acute and chronic knee cases and of open and arthroscopic ligament procedures in the early and delayed motion groups. Associated surgery included four meniscus repairs, three medial collateral ligament repairs, and one lateral collateral ligament repair. Special suturing and fixation techniques were used at surgery to maintain the integrity of ligament and meniscus structures, allowing the surgeon to feel safe in subjecting the joint to early postoperative motion. The objective parameters measured were KT-1000 arthrometer measurements, Cybex isokinetic testing, girth measurements at four lower limb locations, range of motion goniometer measurements, postoperative pain medications, and days of hospitalization. Starting intermittent passive motion on the 2nd postoperative day did not increase joint effusion, hemarthrosis, or soft tissue swelling. In both motion groups, postoperative joint effusions were absent after the 14th postoperative day. There was no statistically significant difference in knee extension or flexion limits, pain medication used, or hospital stay in comparing the two knee motion programs. An important finding of this study was the significant decreases in thigh circumference that occurred within the first few weeks of surgery, which progressed despite a closely supervised inpatient and outpatient rehabilitation program.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
43.
Previously, it has been shown that incorporation of the membrane channel-forming polyene antibiotic, amphotericin B (AMB), into liposomes composed of dimyristoyl phosphatidylcholine/dimyristoyl phosphatidylglycerol (7:3 ratio) results in reduced drug toxicity to animals with full retention of therapeutic activity against systemic fungal infections. In this report we explore the cellular and biochemical bases of the enhanced therapeutic index of liposomal amphotericin B (L-AMB). AMB and L-AMB are equally potent and both promptly induce rapid cation efflux from Candida albicans cells. By contrast, AMB, but not L-AMB, induces cation efflux and cell lysis in mammalian erythrocytes, demonstrating the selectivity of L-AMB at the cellular level. The characteristics of the lipid of the erythrocyte membrane seem to be the most important determinant of cellular sensitivity, since AMB, but not L-AMB, induces cation release from large unilamellar liposomes composed of red cell membrane lipids, thus paralleling the observations on intact cells. The ability of L-AMB to induce cation release and cause toxicity to erythrocytes, however, can be modulated by changing the lipid composition of the liposome carrier. Thus, AMB-containing liposomes composed of phospholipids with saturated acyl chains are nontoxic, whereas AMB liposomes composed of phospholipids containing unsaturated acyl chains are almost as toxic as AMB itself. The acyl chain composition rather than the head group composition seems most important, although substitution of anionic phosphatidylglycerols for phosphatidylcholines contributes somewhat to the protective effect. Analysis of several types of liposomes containing AMB at concentrations up to 5 mol %, using electron paramagnetic resonance and freeze fracture electron microscopy, shows that the drug is incorporated in the lipid bilayer but produces only modest disruptive effects on bilayer structure. Current results are interpreted in terms of a selective transfer of AMB from "donor" liposomes to "target" cell membranes. The transfer process probably occurs by diffusion of AMB through the solvent but is regulated by the physical properties of both donor and target membranes.  相似文献   
44.
医务人员的身心健康和执业满意度直接影响医疗服务质量。复旦大学附属华山医院从员工需求切入,建立并实施员工关爱计划:横向包括身心健康、社会支持、个人成长与职业生涯发展等;纵向贯彻危机前、危机中、危机后三级援助体系。实践后,员工满意度、社会支持水平、幸福感有所提升,职业倦怠阳性率有所下降。员工关爱计划在管理理念、方案完善、人才培养等方面还有待进一步改进。  相似文献   
45.
Advances in Health Sciences Education - This study examines the way in which student characteristics and pre-admissions measures are statistically associated with the likelihood a student will...  相似文献   
46.
ObjectivePatients with rheumatic diseases often have multiple comorbidities which may impact well‐being leading to high psychosocial complexity. This scoping review was undertaken to identify complexity measures/tools used in rheumatology that could help in planning and coordinating care.MethodsMEDLINE, EMBASE and CINAHL were searched from database inception to 14 December 2019 using keywords and Medical Subject Headings for “care coordination”, “complexity” and selected rheumatic diseases and known complexity measures/tools. Articles describing the development or use of complexity measures/tools in patients with adult rheumatologic diagnoses were included regardless of study design. Included articles were evaluated for risk of bias where applicable.ResultsThe search yielded 407 articles, 37 underwent full‐text review and 2 were identified during a hand search with 9 included articles. Only 2 complexity tools used in populations of adult patients with rheumatic disease were identified: the SLENQ and the INTERMED. The SLENQ is a 97‐item patient needs questionnaire developed for patients with systemic lupus (n = 1 study describing tool development) and applied in 5 cross‐sectional studies. Three studies (a practice article, trial and a cross‐sectional study) applied the INTERMED, a clinical interview to ascertain complexity and support coordinated care, in patients with rheumatologic diagnoses.ConclusionsThere is limited information on the use of patient complexity measures/tools in rheumatology. Such tools could be applied to coordinate multidisciplinary care and improve patient experience and outcomes.Patient contributionThis scoping review will be presented to patient research partners involved in co‐designing a future study on patient complexity in rheumatic disease.  相似文献   
47.
目的基于主成分分析(PCA)-决策树模型分析脑卒中肺部感染的危险因素及血清免疫炎性因子的预测价值。方法回顾性分析2014年12月-2019年12月江西省上饶市人民医院确诊的176例脑卒中患者,根据是否发生肺部感染,分为感染组40例和未感染组136例。记录患者临床特征,检测血白细胞(WBC)计数、血清C-反应蛋白(CRP)、降钙素原(PCT)和可溶性白细胞介素-2受体(SIL-2R)水平。采用Logistic回归和卡方自动交叉检验(CHAID)模型分析影响脑卒中后肺部感染的危险因素;受试者工作特征曲线(ROC)分析血WBC、CRP、PCT、SIL-2R预测肺部感染的价值。结果脑卒中肺部感染与患者年龄、卒中类型、是否合并糖尿病、吸烟史、吞咽困难、意识障碍、侵入性操作有关(P<0.05);感染组患者血WBC、CRP、PCT和SIL-2R水平高于未感染组(P<0.05);糖尿病、侵入性操作、CRP和PCT均为影响脑卒中患者肺部感染的独立危险因素(P<0.05);PCA-ROC分析显示,血WBC、CRP、PCT、SIL-2R和联合预测主成分1(PC1)的曲线下面积(AUC)分别为0.670、0.816、0.854、0.686、0.918;PCA-卡方自动交互检测(CHAID)模型分析显示,WBC、CRP、PCT、SIL-2R和PC1预测肺部感染的准确率为77.33%、84.72%、86.90%、79.02%和89.24%。结论血清PCT水平可用于预测脑卒中患者肺部感染的发生,临床可重点关注合并糖尿病、意识障碍和侵入性操作的患者。  相似文献   
48.
目的 探讨血清CA125和唾液酸(SA)对卵巢子宫内膜异位症及卵巢良性肿瘤的诊断价值。方法 对30例卵巢巧克力囊肿、30例卵巢良性肿瘤和15例正常妇女采用放免法测定血清CA125值,比色法测定血清SA值。结果 卵巢巧克力囊肿组血清CA125均值明显高于良性肿瘤组及正常对照组(P<0.01),而血清SA增值三组间无显著性差异(P>0.05)。结论 血清CA125测定对巧克力囊肿有辅助诊断价值,且有助于与卵巢良性肿瘤的鉴别。  相似文献   
49.
IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
50.
The developmental stage at which a neuron becomes committed to a neurotransmitter phenotype is an important time in its ontogenetic history. The present study examines when choline acetyltransferase (ChAT) is first detected within each of four different subsets of cholinergic neurons previously identified in the cervical enlargement of the spinal cord: namely, motor neurons, partition cells, central canal cluster cells, and dorsal horn neurons. By examining the temporal sequence of embryonic development of these cholinergic neurons, we can infer the relationships between ChAT expression and other important developmental events. ChAT was first detected reliably on embryonic day 13 (E13) by both biochemical and immunocytochemical methods, and it was localized predominantly within motor neurons. A second group of primitive-appearing ChAT-positive cells was detected adjacent to the ventricular zone on E14. These neurons seemed to disperse laterally into the intermediate zone by E15, and, on the basis of their location, were tentatively identified as partition cells. A third group of primitive ChAT-immunoreactive cells was detected on E16, both within and around the ventral half of the ventricular zone. By E17, some members of this "U"-shaped group appeared to have dispersed dorsally and laterally, probably giving rise to dorsal horn neurons as well as dorsal central canal cluster cells. Other members of this group remained near the ventral ventricular zone, most likely differentiating into ventral central canal cluster cells. Combined findings from the present study and a previous investigation of neurogenesis (Phelps et al.: J. Comp. Neurol. 273:459-472, '88), suggest that premitotic precursor cells have not yet acquired the cholinergic phenotype because ChAT is not detectable until after the onset of neuronal generation for each of the respective subsets of cholinergic neurons. However, ChAT is expressed in primitive bipolar neurons located within or adjacent to the germinal epithelium. Transitional stages of embryonic development suggest that these primitive ChAT-positive cells migrate to different locations within the intermediate zone to differentiate into the various subsets of mature cholinergic neurons. Therefore, it seems likely that spinal cholinergic neurons are committed to the cholinergic phenotype at pre- or early migratory stages of their development. Our results also hint that the subsets of cholinergic cells may follow different migration routes. For example, presumptive partition cells may use radial glial processes for guidance, whereas dorsal horn neurons may migrate along nerve fibers of the commissural pathway. Cell-cell interactions along such diverse migratory pathways could play a role in determining the different morphological, and presumably functional, phenotypes expressed by spinal cholinergic neurons.  相似文献   
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