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991.
拮氟锐对大鼠肠道氟吸收及微量元素的影响 总被引:1,自引:1,他引:0
拮氟锐是由硼、微量元素和中药制成的抗氟药物。本文应用肠道原位灌流技术。观察了拮氟锐对大鼠肠道氟吸收的干预作用及微量元素的影响。结果透明:拮氟锐可促进肠道BF4的形成,使氟吸收量减少,血氟降低。同时,拮氟锐可拮抗氟所致的微量元素的降低。与硼锌组比较,拮氟锐的抗氟作用效果更明显。 相似文献
992.
目的探讨广东地区宫颈癌组织中HPV16肿瘤相关性抗原E7基因序列的多态性.方法采用通用引物PCR直接测序法对宫颈癌标本中的HPV分型,从含有HPV16型的标本中采用自行设计的多重引物通过巢式PCR扩增出HPV16E7,经DNA序列测定法检测其基因变异,进而寻找其热点突变.结果50例宫颈癌组织HPV-DNA的检出率为78%,其中HPV16和HPV18型混合感染18例,单纯HPV16型感染15例.33例含有HPV16型的标本中扩增出25例HPV16E7,其中17例647位核苷酸“T”变异“C”,导致相应的蛋白质由天冬氨酸变异为丝氨酸.结论广东地区宫颈癌组织中HPV16E7DNA序列发生碱基替换的区域主要在647位至846位,热点突变点为Nt647和Nt846. 相似文献
993.
荆芥连翘汤对促进皮肤溃疡愈合的影响 总被引:4,自引:0,他引:4
目的 观察荆芥连翘汤对小鼠皮肤溃疡的治疗作用。方法 建立小鼠皮肤创伤和烫伤两种皮肤溃疡模型.比较荆芥连翘汤以及rhEGF的用药组和自身对照组小鼠皮肤溃疡面积,用昆微镜观察溃疡面炎症细胞浸润情况。结果 和自身对照组相比,荆芥连翘汤可明显缩小小鼠皮肤溃疡面积(P〈0.001),同时炎症细胞浸润显著减少(P〈0.001);荆芥连翘汤用药组疗效显著优于rhEGF用药组。结论 荆芥连翘汤可明显促进小鼠皮肤溃疡的愈合。 相似文献
994.
V. Gh. MUSTEATA I. T. CORCIMARU I. A. IACOVLEVA L. Z. MUSTEATA I. S. SUHARSCHII L. T. ANTOCI 《International journal of laboratory hematology》2004,26(6):397-401
The purpose of this comparative study was to evaluate the response of primary splenic low‐grade non‐Hodgkin's lymphomas (NHL) to chemotherapy, splenectomy, and chemotherapy combined with splenectomy in order to elaborate the optimum treatment modality. A total of 104 patients (age range: 15–82 years) with primary low‐grade B‐cell NHL of the spleen were comprised by our study. Stage IV disease was determined in 102 (98.1%) cases. Regarding the treatment modality, splenectomy was performed in 14 patients, early splenectomy and single‐agent chemotherapy in 15, early splenectomy and combined chemotherapy in 19, single‐agent chemotherapy in 23, and combined chemotherapy in 33. In the above‐mentioned order, complete remission rate was following: none, 40.0, 31.6, 21.8, and 18.2%. Partial remissions were achieved in 85.7, 46.7, 57.9, 30.4, and 69.7% of cases, respectively. The median remission duration turned out to be longer (74.5 months) in the group of patients with complete remissions attained by means of splenectomy and combined chemotherapy. Local relapses in the spleen developed in 19 (72.7%) patients treated with combined chemotherapy and in 9 (90.0%), who had undergone single‐agent chemotherapy. The 5‐year overall survival was 54.4% after splenectomy, 39.4% after single‐agent chemotherapy, and 37.1% after combined chemotherapy, being significantly higher (P < 0.05) after splenectomy and single‐agent chemotherapy (67.2%), and splenectomy followed by combined chemotherapy (64.7%). Early splenectomy combined with chemotherapy is the optimum treatment option for primary low‐grade NHL of the spleen because of the superiority in complete remission rate, remission duration, and in overall survival rate. Splenectomy leads to somatic compensation of patients, makes impossible local relapsing in the spleen, prevents continuous dissemination from the primary tumor site, and mostly corrects cytopenias, creating better conditions for chemotherapy. 相似文献
995.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。 相似文献
996.
低剂量甲基汞在小鼠体内分布及其对细胞周期进程的影响 总被引:3,自引:0,他引:3
连续90天饮用含甲基汞浓度为1/1000LD50、1/100LD50、1/50LD50和1/10LD50的自来水的雄性昆明小鼠,各脏器中总汞含量均高于对照组(P<0.05~0.005),并且随着染毒剂量增加,脏器中总汞含量也随之增高。同时采用FACScan流式细胞仪和“CellFIT”软件分析脾细胞周期进程,发现除1/1000LD50剂量组外,其余各剂量组从Go/G1时相进入S时相的脾细胞百分数均明显高于对照组(P<0.05),与染毒剂量呈明显正相关。表明连续经口摄入低剂量甲基汞小鼠脾细胞周期进程加快,细胞DNA复制增强。 相似文献
997.
氟罗沙星的体内外试验相关性研究 总被引:4,自引:1,他引:3
本文研究了新型喹诺酮类药物氟罗沙星体外溶出与体内吸收之间的相关性。实验表明,本品口服吸收在血清中达峰时间较快,作用持久,消除半衰期为9.60hr。在人工胃液中溶出速率较快,在血清达峰之前,体内吸收与体外溶出量之间呈现良好的相关性。 相似文献
998.
999.
为探讨国产Fogany导管的气囊直径大小及导管通过血管腔次数多少与动脉管壁急性损伤的关系,本文以14条犬为对象,研究了当Fogany导管气囊直径分别等于血管直径的1、1.5及2倍、导管通过血管腔1、2及3次时,该导管对犬腹主动脉壁所致的超微结构损伤改变。结果显示:气囊直径愈大,导管通过血管腔次数愈多,气囊对动脉内膜及肌层的损伤愈重;从轻微的内皮细胞损伤至内皮及内皮下组织的全部剥脱,以及中膜层平滑肌细胞受损,但大多数损伤局限于内膜层。本研究为此种国产Fogany气囊导管应用于临床提供了实验依据。 相似文献
1000.
Marie V. St-Pierre K. Sandy Pang 《Journal of pharmacokinetics and pharmacodynamics》1995,23(3):243-266
Previous mouse liver studies with diazepam (DZ),N-desmethyldiazepam (NZ), and temazepam (TZ) confirmed that under first-order conditions, DZ formed NZ and TZ in parallel.
Oxazepam (OZ) was generatedvia NZ and not TZ despite that preformed NZ and TZ were both capable of forming OZ. In the present studies, the concentration-dependent
sequential metabolism of DZ was studied in perfused mouse livers and microsomes, with the aim of distinguishing the relative
importance of NZ and TZ as precusors of OZ. In microsomal studies, theK
ms andV
maxs, corrected for binding to microsomal proteins, were 34 μM and 3.6 nmole/min per mg and 239 μM and 18 nmole/min per mg, respectively,
forN-demthylation andC
3-hydroxylation of DZ. TheK
ms andV
maxs forN-demethylation andC
3-hydroxylation of TZ and NZ, respectively, to form OZ, were 58 μM and 2.5 nmole/min per mg and 311 μM and 2 nmole/min per
mg, respectively. The constants suggest that at low DZ concentrations, NZ formation predominates and is a major source of
OZ, whereas at higher DZ concentrations, TZ is the important source of OZ. In livers perfused with DZ at input concentrations
of 13 to 35 μM, the extraction ratio of DZ (E{DZ}) decreased from 0.83 to 0.60. NZ was the major metabolite formed although its appearance was less than proportionate
with increasing DZ input concentration. By contrast, the formation of TZ increased disporportionately with increasing DZ concentration,
whereas that for OZ decreased and paralleled the behavior of NZ. Computer simulations based on a tubular flow model and thein vitro enzymatic parameters provided a poorin vitro-organ correlation. TheE{DZ}, appearance rates of the metabolites, and the extraction ratio of formed NZ (E{NZ, DZ}) were poorly predicted; TZ was incorrectly identified as the major precursor of OZ. Simulations with optimized parameters
imporved the correlations and identified NZ as the major contributor of OZ. Saturation of DZN-demethylation at higher DZ concentrations increased the role of TZ in the formation of OZ. The poor aqueous solubility (limiting
the concentration range of substrates usedin vitro), avid tissue binding and the coupling of enzymatic reactions in liver, favoring sequential metabolism, are possible explanations
for the poorin vitro-organ correlation. This work emphasizes the complexity of the hepatic intracellular milieu for drug metabolism and the need
for additional modeling efforts to adequately describe metabolite kinetics.
This work was supported by the Medical Research Council of Canada (MA-9104). 相似文献