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61.
目的探讨经后路椎管减压结合椎弓根钉棒系统及椎体支柱块治疗胸腰椎爆裂骨折并不全瘫痪的手术方法与临床疗效。方法回顾性分析自2010-01—2014-01采用后路椎管减压结合椎弓根钉棒系统及椎体支柱块治疗胸腰椎爆裂骨折并不全瘫42例,所有患者均为单椎体爆裂骨折。比较术前及术后3 d、3个月、9个月的椎体前缘高度比、Cobb角,术前及末次随访时脊髓神经功能Frankel分级。结果 42例均获得随访12~22个月,平均17个月。末次随访时脊髓神经损伤Frankel分级:A级1例,B级2例,C级5例,D级7例,E级27例。术后3 d、3个月、9个月伤椎椎体前缘高度比分别为(92.3±3.8)%、(91.0±3.6)%、(91.1±3.5)%,较术前明显恢复,差异有统计学意义(F=177.403,P0.001)。术后3 d、3个月、9个月Cobb角分别为(6.0±1.3)°、(6.2±1.4)°、(6.2±1.2)°,Cobb角矫正后明显改善,差异有统计学意义(F=29.310,P0.001)。结论后路椎管减压结合椎弓根钉棒系统及椎体支柱块治疗胸腰椎爆裂骨折并不全瘫痪疗效满意,是满意临床疗效与恢复椎体合理生物力学的有效结合,是较为理想的治疗方法。  相似文献   
62.
目的探讨雌激素对大鼠噪声性听力损失的影响。方法 SD大鼠20只随机分为去势组与对照组,各10只。对两组大鼠进行听性脑干诱发电位(ABR)和畸变产物耳声发射(DPOAE)检测后,去势组行卵巢切除术,对照组行假手术。术后正常饲养3周后所有大鼠同时在隔声室中用强度为115d B SPL(C)的白噪声造模,噪声暴露2周后进行同样听力测试,比较两组在噪声暴露后的听力情况。结果噪声暴露后去势组与对照组大鼠均出现听力下降;对照组在噪声暴露后Click、2、4、6、8k Hz ABR阈值分别为(15.63±1.51)d B n HL、(9.38±1.93)d B n HL、(10.63±2.04)d B n HL、(7.19±1.94)d B n HL、(4.69±1.55)d B n HL,去势组噪声暴露后相应频率阈值分别为(51.50±3.93)d B n HL、(54.75±4.33)d B n HL、(57.25±3.71)d B n HL、(55.50±4.23)d B n HL、(51.75±3.83)d B n HL,两组各频率相比差异均有统计学意义(P0.05),噪声暴露后对照组ABR阈值小于去势组;两组在噪声暴露前后Click ABR阈上20、40、60d B SL潜伏期未出现明显变化(P0.05);对照组在噪声暴露后2、4、6、8k Hz DPOAE信噪比分别为(12.14±3.07)d B、(22.65±7.92)d B、(20.17±12.05)d B、(13.55±11.51)d B(P0.05),去势组在噪声暴露后相应频率信噪比分别为(1.18±6.53)d B、(2.22±5.46)d B、(2.61±3.38)d B、(3.12±3.67)d B,两组各频率相比差异均有统计学意义(P0.05),噪声暴露后对照组DPOAE信噪比大于去势组(P0.05)。结论雌激素对大鼠噪声性听力损伤具有保护作用,主要影响区域在耳蜗。  相似文献   
63.
Recently we demonstrated that in inflammatory bowel disease (IBD) macrophage-oxidative burst activity is increased and NADPH oxidase mRNA is induced. The herbal phenylethanoid acteoside isolated from Plantago lanceolata L. was shown to exhibit anti-oxidative potential. Using the dextran sulphate sodium (DSS)-induced colitis model, in this study we have assessed whether systemic application of acteoside affects colitis. Colitis was induced by DSS in Balb/c mice. Treatment with acteoside (120, 600 microg/mouse/day) was performed intraperitoneally. The colon lengths were determined. Colonic tissue was scored histologically (max. score 8) by a blinded investigator. T cells isolated from mesenteric lymph nodes (MLN) were stimulated with anti-CD3 antibody in the presence of interleukin (IL)-2 (final concentration 10 U/ml). After incubation for 24 h, IL-1beta, IL-6, IL-12 tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma levels in supernatants were analysed by the beadlyte cytokine detection system. Histological scoring of colonic tissue revealed that application of acteoside was followed by a significantly improved histological score. In acute colitis the histological score was 3.2 with acteoside versus 5.2 with phosphate-buffered saline (PBS) (P < 0.02). In chronic colitis both 120 microg (3.3 versus 5.2) or 600 microg acteoside (3.0 versus 5.2) significantly ameliorated colitis (both P < 0.02). Stimulated MLN from mice with chronic DSS-induced colitis treated with acteoside showed a significant down-regulation of IFN-gamma secretion (195 pg/ml with 600 microg acteoside versus 612 pg/ml with PBS, P < 0.02). Inhibition of oxidative burst activity with acteoside reduced mucosal tissue damage in DSS colitis and could be a therapeutic alternative for IBD treatment. Further studies of this agent are warranted.  相似文献   
64.
目的:探讨用前路椎管减压、自行研制的纳米羟基磷灰石/聚酰胺66(n-HA/PA66)复合生物活性人工椎体支撑植骨治疗胸腰椎爆裂型骨折合并截瘫的临床疗效。方法:2003年12月—2006年1月收治胸腰椎爆裂型骨折合并截瘫40例,年龄17~62岁。受伤部位:T_(12)5例、L_1 16例、L_2 13例、L_3 6例。神经损害按Frankel分级:A级7例、B级19例、C级8例、D级6例。所有病例均行前路椎管减压、n-HA/PA66复合生物活性人工椎体支撑植骨、钛钉板或钉棒系统内固定。结果:所有病例术后均获得6~25个月(平均13个月)的随访。神经功能:除5例Franel A级和2例D级无变化外,其余均有1~2级的改善。其中由A级到B级2例;B级到C级7例,B级到D级12例;C级到D级5例,C级到E级3例;D级到E级4例。36例伤椎接近解剖复位,6例复位良好。术前伤椎前缘高度平均为椎体的42.8%,术后平均为90.5%,重建的椎体高度无丢失。矢状面Cobb角术前平均为28.4°,术后平均为14.6°。n-HA/PA66复合生物活性人工椎体于术后3~6个月骨性融合。无感染、无椎体移位和断钉等并发症。结论:前路n-HA/PA66复合生物活性人工椎体支撑植骨能有效恢复和维持伤椎的结构和高度,可避免取自体髂骨植骨,是一种有效的脊柱前路重建方法。  相似文献   
65.
目的:探讨3D打印钛网预成形联合术后严密护理对眼眶爆裂骨折患者预后情况的影响。方法:选取笔者医院收治的眼眶爆裂性骨折患者122例,随机分为对照组和观察组,分别62例和60例。对照组患者予以常规钛网置入术,观察组患者予以3D打印钛网预成形,术后均予以视力监测、眼肌运动训练等严密护理。观察并比较两组患者钛网贴合度,复视、眼球运动及眼球突出等症状的改善情况。结果:观察组患者CT矢状位上修复眼眶底的钛网呈S形,对照组患者呈弯向眼眶内的弧形。术后3个月、6个月,观察组患者复视、眼球运动受限情况治愈率均高于对照组,差异具有统计学意义(P<0.05);术后,两组患者患眼眼球突出度差值均降低,观察组显著低于对照组,差异具有统计学意义(P<0.05)。结论:3D打印钛网预成形与眼眶爆裂性骨折患者眶底契合度更高,联合术后严密护理对复视、眼球运动受限及眼球突出等症状的改善作用更好,患者预后更好。  相似文献   
66.
Context: Searching for polymorphonuclear neutrophils (PMNs) respiratory burst inhibitors is an important topic in the treatment of human diseases associated with inflammation.

Objective: To investigate the inhibitory effects of phenolics isolated from Artocarpus styracifolius Pierre (Moraceae) on respiratory burst induced by phorbol myristate acetate (PMA).

Materials and methods: The anti-respiratory burst activities of eight phenolics (20?µM) were assessed by determining luminol-dependent chemiluminiscence in rat PMNs. Cytotoxicity of active compounds (1–1000?µM) was assayed by Trypan blue dye exclusion method. Cell-free models were employed to evaluate scavenging capacity of active compounds (20?µM) against reactive oxygen species.

Results: The PMA-induced respiratory burst was significantly inhibited (p?1–6) at the concentration of 20?µM (below the toxic concentration) with the inhibition rate ranging from 25.0 to 99.6%. The inhibitory potency estimated by IC50 was in the order of AS1 (3.1?µM) >AS6 (5.9?µM) >AS2 (9.1?µM) >AS3 (10.0?µM) >AS5 (29.7?µM) >AS4 (57.7?µM). AS14, four isoprenylated flavones, potently quenched superoxide anion, hydroxyl radical, and hydrogen peroxide at the concentration of 20?µM with their scavenging rates in the range of 30.1–78.1%, 35.4–69.7%, and 65.5–86.3%, respectively. In contrast, AS56, two isoprenylated 2-arylbenzofurans, showed less effect than that exhibited by AS14.

Conclusion and discussion: The isoprenylated phenolics from A. styracifolius can potently inhibit PMA-induced respiratory burst in rat neutrophils without showing cytotoxicity. The inhibitory effects of these isoprenylated phenolics on the respiratory burst might depend on their different types of structure.  相似文献   
67.
Background contextThoracolumbar burst fractures have good outcomes when treated with early ambulation and orthosis (TLSO). If equally good outcomes could be achieved with early ambulation and no brace, resource utilization would be decreased, especially in developing countries where prolonged bed rest is the default option because bracing is not available or affordable.PurposeTo determine whether TLSO is equivalent to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures with respect to their functional outcome at 3 months.Study designA multicentre, randomized, nonblinded equivalence trial involving three Canadian tertiary spine centers. Enrollment began in 2002 and 2-year follow-up was completed in 2011.Patient sampleInclusion criteria included AO-A3 burst fractures between T11 and L3, skeletally mature and older than 60 years, 72 hours from their injury, kyphotic deformity lower than 35°, no neurologic deficit. One hundred ten patients were assessed for eligibility for the study; 14 patients were not recruited because they resided outside the country (3), refused participation (8), or were not consented before independent ambulation (3).Outcome measuresRoland Morris Disability Questionnaire score (RMDQ) assessed at 3 months postinjury. The equivalence margin was set at δ=5 points.MethodsThe NO group was encouraged to ambulate immediately with bending restrictions for 8 weeks. The TLSO group ambulated when the brace was available and weaned from the brace after 8 to 10 weeks. The following competitive grants supported this work: VHHSC Interdisciplinary Research Grant, Zimmer/University of British Columbia Research Fund, and Hip Hip Hooray Research Grant. Aspen Medical provided the TLSOs used in this study. The authors have no financial or personal relationships that could inappropriately influence this work.ResultsForty-seven patients were enrolled into the TLSO group and 49 patients into the NO group. Forty-six participants per group were available for the primary outcome. The RMDQ score at 3 months postinjury was 6.8±5.4 (standard deviation [SD]) for the TLSO group and 7.7±6.0 (SD) in the NO group. The 95% confidence interval (?1.5 to 3.2) was within the predetermined margin of equivalence. Six patients required surgical stabilization, five of them before initial discharge.ConclusionsTreating these fractures using early ambulation without a brace avoids the cost and patient deconditioning associated with a brace and complications and costs associated with long-term bed rest if a TLSO or body cast is not available.  相似文献   
68.
《Toxicology in vitro》2014,28(7):1249-1258
In vitro treatment of human peripheral blood neutrophils from smokers and non-smokers with an aqueous cigarette smoke (CS) extract resulted in a concentration-dependent increase in surface expression of CD11b and CD66b and a corresponding decrease of CD62L, together with a concentration-dependent release of MMP-8, MMP-9, and lactoferrin, indicating considerable activation and degranulation. However, the burst response to N-formyl-methionyl-leucyl-phenylalanine (fMLP) was unchanged in CS-stimulated neutrophils from both smokers and non-smokers. When supernatants from CS-treated monocytic MonoMac-6 (MM6) cells were used for activation of neutrophils, concentration-dependent changes in surface marker expression, granule protein release, and the oxidative burst response to fMLP were observed, again with no major differences between smokers and non-smokers. CS-treated MM6 cells released significant amounts of IL-8 and TNF-α into the culture supernatant. However, antibody blocking experiments showed that only TNF-α mediated the increased burst response in neutrophils. These data show that, in the presence of secondary cells, CS is able to prime neutrophils for an increased burst response to fMLP which is mediated by TNF-α, released from the secondary cells in response to CS. Following stimulation with priming agents, peripheral blood neutrophils from healthy smokers show an equal burst response compared to those from non-smokers.  相似文献   
69.
Effector functions of the elastin receptor on human phagocytic cells from young and older individuals were studied. In cells of young healthy subjects the elastin peptides, the agonists of receptor, stimulated both superoxide anion release from PMNs and phagocytosis of coated human red cells by monocytes. Elastin appeared to inhibit the cholesterol synthesis in monocytes, measured by the incorporation of 14C-acetate. In comparison with phagocytic cells of young (≤25 ± 6 years) subjects, PMNs of elderly donors (≥75 ±10 years) bore a similar number of binding sites for soluble elastin peptides, and the affinity of the elastin receptor was unchanged as shown by Scatchard analysis. The phagocytosis of coated human red cells stimulated by elastin peptides was also similar in the two age groups. However, several differences were found between phagocytic cells of young and elderly donors 1) PMNs of elderly released increased amounts of elastase from both resting and elastin peptide stimulated cells, and 2) monocytes of elderly showed a lack of inhibition of cholesterol synthesis by elastin peptides when maintained in cholesterol-free medium. These changes in effector functions of phagocytic cells from elderly donors might contribute to the age-dependent increase of susceptibility to the development of atherosclerotic lesions.  相似文献   
70.
Conclusions: The results support the idea that auditory steady-state response (ASSR) is a more accurate test for studying age-related hearing loss (ARHL) in Sprague-Dawley rats. Differences in the rat middle ear may explain the variations of the click properties, with a displacement of the energy toward the 8 and 10 kHz frequencies compared with humans. Objectives: The purpose of this study was to evaluate ARHL in older and younger Sprague-Dawley rats using auditory clicks and tone burst with auditory brainstem response (ABR), in addition to ASSR. Methods: This was a prospective cohort study with 50 animals divided into 5 groups based on their age in months. A total of 100 registers were elicited from each one of the 3 auditory measurements systems in an electrically shielded, double-walled, sound-treated cabin. Nine frequencies, from 0.5 to 16 kHz were analyzed with the auditory steady-state response and compared with the results elicited by the clicks and tone-burst ABR. Results: Comparisons between the different frequencies showed lower thresholds in those frequencies below 2 kHz, independently of their age in months. The ARHL was detected by each one of the three auditory measurement systems, but with lower thresholds with the ASSR test. Finally, auditory clicks showed better correlations with 8 and 10 kHz elicited by ASSR, which was different to what was expected, based on human studies.  相似文献   
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