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941.
942.
目的研究脊髓损伤后热休克蛋白27(HSP27)、表皮脂肪酸结合蛋白(FABPs)和金属蛋白酶组织抑制因子-1(TIMP-1)的基因表达及甲基强的松龙(MP)对其表达的影响.方法SD大鼠30只.随机分为假手术组、单纯脊髓损伤组(损伤组)及脊髓损伤+大剂量MP治疗组(MP组),每组10只.应用改良的Allen's打击法致T8脊髓损伤.MP组大鼠伤后即刻从尾静脉内注射大剂量MP(30mg/kg).损伤后24h切取损伤平面上下0.5cm的脊髓组织,进行RT-PCR反应,检测HSP27、FABPs和TIMP-1的基因表达.结果术后24h假手术组HSP27、FABPs和TIMP-1的基因表达相对丰度分别为0.0643±0.0152、0.6413±0.1005和0.7091±0.0577;损伤组上述三个因子的表达升高,分别为1.0013±0.3861、1.2187±0.2851和0.8971±0.1092,与假手术组比较差异有显著性(P<0.01、P<0.05、P<0.05);MP组上述三个因子的表达继续升高,分别为1.2858±0.1384、1.7122±0.1766和1.2081±0.1093,与损伤组比较差异有显著性(P<0.05、P<0.01和P<0.01).结论脊髓损伤后,邻近损伤处的脊髓组织中HSP27、FABPs及TIMP-1的基因表达显著增高,大剂量MP能进一步促进三个因子表达,发挥组织保护作用.  相似文献   
943.
High tibial osteotomy changes the patella and tibial condyle position, which makes the subsequent total knee replacement technically demanding. From 1 January 1993 to 31 December 2000, combined osteotomy [After the first osteotomy made 2 cm distally to the joint line, a bone wedge is removed based laterally. Its tip ends at the center of the tibial condyle (half bone wedge). The distal part of the tibia is placed into the valgus position and the half bone wedge is placed into the gap opened medially.] was performed on 103 knees and closing wedge osteotomy was performed on 47 consecutive knees. Eighty combined (group A) and 41 closing wedge (group B) osteotomy were studied. All knees were assessed radiologically before surgery, in the 10th postoperative week, in the 12th postoperative month and at the time of the final follow-up (in group A—66.15 months, in group B—66.61 months). We examined the change of the femorotibial angle, of the patellar height according to the method of Insall and Salvati, of the tibial slope angle according to the method of Bonnin, of the tibial condylar offset according to the method of Yoshida and of the distance between the lateral tibial plateau and the top of the fibular head. In group A and B, the recurrence of the varus deformity was not noted and valgus alignment did not increase in any case. In group-A, the Insall–Salvati ratio remained unchanged in 65% of knees. The tibial slope angle decreased in both groups. There was correlation between the change of the tibial condylar offset and the angle of the correction in both groups. There was correlation between the change of the distance between the lateral tibial plateau and the top of the fibular head. After combined osteotomy, the transposition of the tibial condyle and the decrease of the distance between the lateral tibial plateau and the top of the fibular head was less than after closing wedge osteotomy, although the average angle of correction was more after combined osteotomy (11.835°), than after closing wedge osteotomy (9.465°). Theoretically, the recurrence of the varus deformity, the increase of the valgus alignment and (in majority of cases) the shortening of the patellar tendon do not compromise the likelihood of successful conversion to the subsequent total knee replacement, either after combined or after closing wedge osteotomy. The combined osteotomy does not lead to considerable transposition of the tibial condyle and to considerable lateral tibial bone loss; therefore, theoretically, the combined osteotomy does not impair the subsequent total knee replacement.  相似文献   
944.
目的探讨永磁速愈贴对切13的消肿止痛,促进伤口愈合和防止疤痕粘连与普通敷料进行对比观察。方法将住院行妇产科手术100例患者与同期住院的手术患者进行对比观察。结果永磁速愈贴切13愈合佳者84.0%,良好者13.0%,愈合差为3.0%,而普通敷料为28.0%、60.0%和12.0%,p〈0.01(x^2=63.660)。结论永磁速愈贴切口具有透气、保湿、促进伤口愈合、消肿、止痒,防止疤痕形成等作用。而普通敷料透气性差,保湿性差,术后切口有红肿、缝线反应、切口愈合时间长及切口局部愈合后有痛痒感。  相似文献   
945.
目的观察罗格列酮和二甲双胍联合氯米芬治疗肥胖型多囊卵巢综合征患者的内分泌改善及生殖功能的临床疗效。方法50例肥胖型PCOS患者分别给予罗格列酮4mg/d和二甲双胍1500mg/d联合氯米芬100mg/d,治疗3个月,比较治疗前后体重指数、内分泌参数、腰臀比和Hom a IR的变化。结果用罗格列酮治疗后排卵率为88%,周期排卵率为64.29%,优势卵泡平均个数为1.8±0.8个,妊娠率为56%,而用二甲双胍治疗后分别为72%、54.84%、1.1±0.6个、48%。两者治疗后能使LH、LH/FSH、T的血清浓度明显下降,SHBG的浓度明显上升,Hom a IR明显改善。结论罗格列酮和二甲双胍联合氯米芬治疗肥胖型多囊卵巢综合征疗效可靠。二甲双胍有降低体重作用、价格便宜,适用于肥胖型P-COS伴胰岛素抵抗不严重者;罗格列酮在胰岛素增敏作用优于二甲双胍,适用于胰岛素抵抗较严重的PCOS患者。  相似文献   
946.
947.
探讨引发产褥期深静脉栓塞的危险因素,加强早期观察,实施有效的预防措施,以及产褥期深静脉栓塞病人的护理对策。  相似文献   
948.
949.
BACKGROUND: One of the major mechanical functions of collagenous tissues is the storage, transmission and dissipation of elastic energy during mechanical deformation. In skin, mechanical energy is stored during loading and then is transmitted and dissipated, which protects skin from mechanical failure. Thus energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices. METHODS: A uniaxial incremental stress relaxation test method has been used to characterize the time-dependent (viscous) and time-independent (elastic) properties of human dermis. Viscoelasticity was investigated in processed human dermis that was equilibrated at pHs of 3.0, 7.4 and 11.0 in an effort to study the link between electrostatic interactions within the collagen matrix and macroscopic tissue properties. RESULTS: Our results show that the solution pH and the charge on collagen significantly affected the high-strain elastic behavior of dermis; the elastic behavior of skin has previously been shown to be directly correlated with axial stretching of the collagen triple helix in crosslinked collagen fibrils. A positive linear correlation existed between the high-strain elastic modulus and both pH (R(2)=0.96) and the total number of charged residues on collagen (R(2)=0.93). These results provide in vitro/ex vivo evidence that charged groups on the surface of collagen molecules in processed human skin influence the high-strain elastic properties of dermis and are likely to be involved in elastic energy storage. CONCLUSION: It is proposed that the pH and charged residue dependency of the elastic modulus suggests that charged pair interactions and repulsions within and between collagen molecules are involved in elastic energy storage during stretching at high strains. It is hypothesized that elastic energy storage is associated with the stretching of pairs of charged amino acid residues that are found primarily in the flexible regions of collagen molecules.  相似文献   
950.
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin.  相似文献   
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