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991.
目的构建鸡胚背根节细胞3D生长模型,观察CSPG对不同浓度的琼脂糖水溶胶培养基对鸡胚背根节神经突起生长的影响。方法①利用多肽缩合剂1’1羰基二咪唑介导CS-B长链与琼脂糖凝胶共价结合。②分别配制0.5%、0.75%、1%、1.25%、1.5%的SeaPrep琼脂糖凝胶溶液和共价结合了CS-B多糖长链的琼脂糖凝胶溶液。取孵育9~10天后鸡胚背根节加入上述凝胶溶液加培养液培养。③培养24小时之后在24 h、48 h7、2 h、96 h进行观察拍照。观察各时间点神经突起生长情况。结果①鸡胚背根节神经突起在1.25%的琼脂糖凝胶溶液中开始呈3D生长,在小于1%的琼脂糖溶液中只能2D生长。②在同一时间点,呈2D生长的背根节突起和呈3D生长的背根节突起在突起长度方面没有统计学差异(P>0.05)。③3D生长的DRG神经突起在共价结合了CS-B的琼脂糖凝胶中生长长度明显短于普通琼脂糖水凝胶(P<0.05),并且可观察到部分突起长出短而直的成束突起。但是对于呈2D生长的DRG突起长度在两种培养基中却未见差异(P>0.05)。结论鸡胚背根节神经元周围突起生长长度在3D培养中与在2D培养中有没有明显的差异。硫酸软骨素能够有效抑制呈3D生长的神经节突起生长,并且影响到神经突起的生长方式。但是在2D培养基中,未能看到上述的抑制作用。 相似文献
992.
目的 探讨书法练习对儿童心理健康发展的作用.方法 选取参加书法练习的小学三年级学生87人作为实验组,未参加书法练习的小学三年级学生37人作为控制组,经过2年的追踪,比较被试在焦虑、神经过敏性以及行为问题上的变化.结果 ①实验组和控制组被试在2年的追踪期间,其总体的焦虑和神经过敏性水平呈显著上升趋势,但实验组被试的上升幅度显著低于控制组被试;②实验组和控制组被试在2年的追踪期间,其行为问题呈显著下降趋势,但实验组被试行为问题水平显著低于控制组被试的行为问题水平.结论 书法练习在一定程度上能够增进儿童的心理健康. 相似文献
993.
994.
Rapid non-genomic inhibitory effects of glucocorticoids on human neutrophil degranulation 总被引:4,自引:0,他引:4
L. Liu Y. X. Wang J. Zhou F. Long H. W. Sun Y. Liu Y. Z. Chen C. L. Jiang 《Inflammation research》2005,54(1):37-41
Background: Glucocorticoids acting as anti-inflammatory or immunosuppressive drugs have been shown to exert most of their effects genomically. Recent findings suggest that non-genomic activity might be relatively more important in mediating the therapeutic effects of high-dose pulsed glucocorticoid. However, few non-genomic anti-inflammatory effects were reported, much less non-genomic mechanisms.Objective: This study was performed to investigate the nongenomic effects of glucocorticoids on human neutrophil degranulation.Methods: Purified human neutrophils were pretreated with 6 -methylprednisolone or hydrocortisone for 5 min, and then primed with N-formyl-methionyl-leucyl-phenylalanine (fMLP) (10–6 M) or phorbol myristate acetate (PMA) (50 ng/ml) in the presence of cytochalasin B. The release of two markers of neutrophil granules, lactoferrin and myeloperoxidase, was measured by ELISA and enzymology methods respectively.Results: Both 6 -methylprednisolone (10–5–10–4 M) and hydrocortisone (10–4 M) showed significant inhibitory effects on neutrophil degranulation within 5 min after fMLP administration. For PMA stimulated degranulation, 6 -methylprednisolone (10–4 M) showed significant inhibitory effects (p < 0.01), while hydrocortisone (10–4 M) only showed an inhibitory tendency (P > 0.05). Neither RU486 (10–5 M) nor cycloheximide (10–4 M) could alter the inhibitory effects of glucocorticoids.Conclusion: Our results demonstrate that megadoses of glucocorticoids exert rapid inhibitory effects on human neutrophil degranulation at the cellular level via a new mechanism that is independent of corticosteroid type II receptor occupation or protein synthesis. We infer that these effects may be very important when glucocorticoids act as anti-inflammatory drugs during pulse therapy.Received 20 May 2004; returned for revision 21 July 2004; accepted by M.J. Parnham 23 September 2004L. Liu and Y. X. Wang contributed equally to this work. 相似文献
995.
996.
目的:探讨颈椎后路手术治疗颈椎退变性疾病后颈椎曲度不良与疗效的相关性。方法:采用颈椎后路减压术治疗颈椎退变性疾病患者85例,其中全椎板减压术26例、单开门椎管扩大成形术39例和单开门棘突重建扩大成形术20例,观察手术后颈椎后凸畸形对治疗效果的影响。结果:经6-72个月,平均18个月随访,颈椎后凸与否,各组之间神经功能改善率差异无统计学意义(P〉0.05);单开门椎管扩大成形术与单开门棘突重建椎管扩大成形术,术后颈椎后凸发生率低于全椎板减压术(P〈0.05);颈椎无后凸与轻度后凸(与A、B、C的对应关系)畸形之间的轴性症状发生率无差异,但与明显后凸组相比有差异性(P〈0.05)。结论:颈椎后路减压术是治疗颈椎退变性疾病常用的手术方法,具有椎管容积扩大明显等优点。但减少手术对后方肌肉韧带复合体损伤并对此复合体进行有效修复,可以减少颈后凸畸形和轴性症状发生,提高手术效果。 相似文献
997.
以50例脑梗塞为观察组,45例健康人为对照组,观察噻氯匹定对脑梗塞血小板聚集功能和血液流变学的影响。(1)治疗前,观察组血小板聚集率(PAR)非常显著地高于对照组(P<0.01),(2)治疗后,观察组PAR非常显著地低干治疗前(P<0.01),与对照组比较已无显著性差异(P>0.05),(3)观察组各亚组治疗后PAR大多非常显著地低于治疗前(P<0.01)。(4)观察组治疗前后血液流变学指标无显著性变化(P>0.05),(5)神经功能缺损评分:治疗前15.8±0.98;治疗后8.2±5.4,差异有非常显著意义(P<0.01)。 相似文献
998.
Production of a hybridoma cell line secreting retinoic acid-specific monoclonal antibody 总被引:1,自引:0,他引:1
A stabilized hybridoma cell line secreting anti-retinoic acid monoclonal antibodies of subclass IgG1 with kappa chains was produced by fusing NS-1 myeloma cells with the spleen cells from BALB/c female mice immunized with all-trans-4-oxoretinoic acid-oxime-chicken IgG conjugate. The antibody titer of mice ascitic fluid ranged from 1/12,800 to 1/25,600, as determined by competitive indirect enzyme-linked immunosorbent assay (ELISA). 50% inhibition dosage of all-trans-retinoic acid at a 1/20,000 dilution of mice ascitic fluid was 6.6 ng/ml, as determined by ELISA. The anti-retinoic acid monoclonal antibody was generated in mice ascitic fluid and purified by protein G affinity chromatography. Cross-reactivity of the monoclonal antibody was determined at 0.1 microgram/ml concentration of retinoids and indicated high specificity to both all-trans-retinoic acid (86% inhibition) and 13-cis-retinoic acid (87% inhibition), and strong cross-reactivity with 4-oxoretinoic acid (77%) and 4-oxoretinoic acid oxime (109%). Specificity was confirmed by the horseradish peroxidase-linked immunostaining method and immunoradioassay. The affinity constant of the monoclonal antibody, K, was determined to be 3.6 X 10(9) l/mol. A calibration curve for retinoic acid using the monoclonal antibody to retinoic acid was developed; the detection limit for all-trans-retinoic acid is 1 ng/ml in the competitive indirect ELISA. The antibody counteracts the effect of retinoic acid on growth inhibition and differentiation in HL-60 cells. 相似文献
999.
Altered sensitivity to and clearance of propranolol in men of Chinese descent as compared with American whites 总被引:9,自引:0,他引:9
H H Zhou R P Koshakji D J Silberstein G R Wilkinson A J Wood 《The New England journal of medicine》1989,320(9):565-570
To determine whether the pharmacokinetics and pharmacodynamics of beta-blockade differ among racial groups, we gave 10 men of Chinese descent and 10 American white men 10, 20, 40, and 80 mg of propranolol every eight hours; the dosages were given in random order, and each dose was given for one day. The degree of beta-blockade was measured as the reduction in the heart rate and blood pressure in the supine and upright positions and during treadmill exercise testing. The Chinese subjects had at least a twofold greater sensitivity to the beta-blocking effects of propranolol than the white subjects, as indicated by the mean (+/- SEM) plasma concentrations producing a 20 percent reduction in the heart rate in both the supine position (197 +/- 31 vs. 536 +/- 58 nmol per liter; P less than 0.05) and the upright position (131 +/- 27 vs. 343 +/- 39 nmol per liter; P less than 0.05) and after exercise testing (96 +/- 12 vs. 185 +/- 23 nmol per liter; P less than 0.05). In addition, the Chinese subjects had much greater sensitivity to the hypotensive effects of propranolol, as shown by the concentrations that reduced blood pressure by 10 percent in the supine position (73 +/- 5 vs. 748 +/- 7 nmol per liter; P less than 0.01) and in the upright position (89 +/- 5 vs. 401 +/- 6 nmol per liter; P less than 0.01). No difference in beta-receptor density or affinity of lymphocytes was found between the groups. The Chinese group had a 45 percent higher free fraction of propranolol in plasma, which may have contributed to the increased drug effect but cannot explain it entirely. This group metabolized propranolol more rapidly than the white group, which resulted in a 76 percent higher clearance of an oral dose (3740 +/- 737 vs. 2125 +/- 214 ml per minute; P less than 0.05) because of increased metabolism through multiple metabolic pathways. We conclude that Chinese men have greater sensitivity than white men to the effects of propranolol on heart rate and blood pressure. Decreased protein binding may be responsible in part, but most of the effect remains to be explained. 相似文献
1000.