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101.
ABSTRACT— Glafenine was associated with hepatic injury in 38 cases. The causal relationship was assessed on the basis of the temporal relationship with drug use, course and exclusion of other causes. In 27 cases a causal relationship was considered likely, i.e. ‘probable’ (12 cases) or ‘possible’ (15 cases), whereas in 11 cases it was either unlikely or unclassifiable. In both the ‘probable’ and ‘possible’ groups 60–70% of individuals were women. Jaundice was present in three-quarters of cases in both groups. Eosinophilia was more frequent in the group of ‘probable’ cases, and this group had the highest case-fatality rate (42%). Onset varied from 2 days (after a rechallenge) to 8 months, but most cases appeared between 2 weeks and 4 months after starting therapy. Histology in 22 cases showed a predominantly hepatocellular pattern, varying from spotty panlobular necrosis, centrilobular and (sub)massive necrosis (acute pattern) to fibrosis and cirrhosis (chronic pattern). The chemical structure of glafenine and the clinicopathological pattern it induces resemble that of cinchophen. The incidence is unknown. Either metabolic idiosyncrasy or an immunoallergic mechanism seems to be responsible. 相似文献
102.
103.
The clinical, light microscopic, and ultrastructural features of a carcinoid tumor occurring in the larynx of an 80-year-old man are presented and compared with 22 laryngeal carcinoids described in the world literature. These 23 tumors occurred in persons from 45 to 80 years of age (mean age was 61 years) and were three times more common in men than in women. Hoarseness was the most common presenting symptom. Sixty-one percent of the tumors were supraglottic, 26% were transglottic, 4% were glottic, 4% were subglottic, and 4% were unspecified. At least 15 (65%) of the patients are known to have developed metastases. Nine of these (60%) presented with only regional lymph node metastases, one of which was occult. Surgery is the treatment of choice, with the extent dependent on the stage of disease. Radiation therapy appears ineffective, and chemotherapy is largely untested. The 2- and 4-year determinate survival rates were 59% and 25%, respectively. 相似文献
104.
A microcapillary method utilizing phthalate esters or an ultracentrifuge method are both capable of separating autologous from homologous erythrocytes in polytransfused patients. The microcapillary technique which is readily adaptable to blood bank laboratories provides a previously unavailable method for defining blood group antigen typings in transfused patients. Such typings are of vital importance in the laboratory evaluation of transfused patients with multiple or weak blood group antibodies. 相似文献
105.
106.
Studies on the mechanism of bacterial resistance to complement-mediated killing. II. C8 and C9 release C5b67 from the surface of salmonella minnesota S218 because the terminal complex does not insert into the bacterial outer membrane 总被引:22,自引:2,他引:22 下载免费PDF全文
The mechanism for consumption of terminal complement components and release of bound components from the surface of serum-resistant salmonella minnesota S218 was studied. Consumption of C8 and C9 by S218 occurred through interaction with C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8-deficient serum and washed to remove all C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8- deficient serum and washed to remove al but cell bound C5b67. Rapid release of (125)I C5 and (125)I C7 from the membrane of S218 was dependent on binding of C8 because (125)I C5 and (125)I C7 deposition in C8D serum was stable and was twofold higher in C8D than in PNHA, and addition of purified C8 or C8 and C9 to S218 previously incubated in C8D serum caused rapid release of (125)I C5 and (125)I C7 from the organism. Analysis by sucrose density gradient ultracentrifugation of the fluid phase from the reaction of S218 and 10 percent PNHS revealed a peak consistent with SC5b-9, in which the C9:C7 ratio was 3.3:1, but the NaDOC extracted bound C5b-9 complex sedimented as a broad peak with C9:C7 of less than 1.2:1. Progressive elution of C5b67 and C5b-9 from S218 but not serum-sensitive S. minnesota Re595 was observed with incubation in buffers of increasing ionic strength. Greater than 90 percent of the bound counts of (125)I C5 or (125)I C9 were released from S218 by incubation in 0.1 percent trypsin, but only 57 percent of (125)I C9 were released by treatment of Re595 with trypsin. These results are consistent with the concept that C5b-9 forms on the surface of the serum-sensitive S. minnesota S218 in normal human serum, but the formed complex is released and is not bactericidal for S218 because it fails to insert into hydrophobic outer membrane domains. 相似文献
107.
108.
H. K. DÜRR CHRISTIANE BODE R. KRUPINSKI J. CH. BODE 《European journal of clinical investigation》1978,8(3):189-191
Macroamylasaemia was produced in vitro by incubation of hydroxyethylstarch with serum, and in vivo by intravenous infusion of hydroxyethylstarch. Gel filtration on Sephadex G-100 revealed distinct differences in molecular size distribution between such hydroxyethylstarch-induced macroamylase and the usual form of naturally occurring macroamylase which was observed in a few patients from our hospital. Further studies demonstrated that the gel filtration elution pattern of amylase activity in serum containing hydroxyethylstarch-induced macroamylase is significantly altered with time in vitro and in vivo, probably because of an enzymatic degradation of the hydroxyethylstarch components of the macromolecular complexes. In a healthy volunteer the serum amylase activity was elevated to a maximum of 797 u/l and the renal clearance rate of amylase was diminished to a minimum of 0.3 ml/min after infusion of 500 ml of a 6% solution of hydroxyethylstarch, as compared to 300 u/l, and 0.95 ml/min, respectively, during the pre-infusion period. 相似文献
109.
目的:骨唾液酸蛋白在骨矿化形成方面扮演重要角色,实验观察其是否能诱导体外培养的人骨髓间充质干细胞向成骨细胞分化。方法:实验于2005—10/2006—12在解放军广州军区广州总医院医学实验科完成。①材料来源:选取在本院体检的健康志愿者2人,对本实验均知情同意。采用Ni-NTA亲和纯化技术,从本室构建的毕赤酵母GS115/pPICZaA-hbsp发酵上清中纯化重组人骨唾液酸蛋白。②实验方法:对健康志愿者进行髂骨穿刺抽取骨髓液,采用贴壁法培养得到骨髓间充质干细胞。设立4组:骨唾液酸蛋白组添加0.1nmol/L骨唾液酸蛋白;成骨诱导液组添加10nmol/L地塞米松、10mmol/L磷酸甘油、50mg/L抗坏血酸;联合组添加上述两组的所有试剂;空白对照组不添加任何处理因素;各组均处理细胞12d。⑧实验评估:光镜及电镜观察培养的细胞形态;以细胞计数法测定生长曲线,应用流式细胞仪分析细胞周期,采用免疫荧光细胞化学法和流式细胞分析检测干细胞标志物STRO-1的表达;生化试剂盒测定碱性磷酸酶活性;von Kossa染色法检测钙沉积。结果:①单个骨髓间充质干细胞为长梭形,经骨唾液酸蛋白处理后细胞大而扁平,原来密集的克隆分散开。②与空白对照组比较,骨唾液酸蛋白组引起细胞生长曲线右移,细胞Go/G,期比例平均增加12.09%(P〈0.01),S期比例减少65.92%(P〈0.01),STRO-1阳性细胞百分率下降26.54%(P〈0.01)。⑧与空白对照组比较,骨唾液酸蛋白组细胞碱性磷酸酶活性增加50.0%,成骨诱导液组增加59.5%,联合组增加71.43%,并且随着处理时间的延长,活性增加越显著。④空白对照组细胞vonKossa染色呈阴性,其余各组均呈阳性。其中联合组的黑色矿化结节体积最大、数目最多;骨唾液酸蛋白组的结节体积较小、数目较少;成骨诱导液组居中。结论:骨唾液酸蛋白对人骨髓间充质干细胞有促进成骨分化和矿化作用,且与成骨诱导液联用效果更佳。 相似文献
110.
Chemoattractant-receptor coupling triggers several biologic responses in phagocytic cells including activation of the respiratory burst. Prior evidence in intact cells implied that stimulation of the respiratory burst by chemoattractants was by a mechanism different from other soluble agents suggesting the possibility that different oxidative enzymes were responsible. We now show that the chemoattractants N-formyl-methionyl-leucyl-phenylalanine and a split fragment of the fifth component of complement (C5a) stimulate an NADPH oxidase activity, measured in the 50,000-g particulate fraction from human polymorphonuclear leukocytes (PMN). Levels of oxidase activity stimulated by the chemoattractants were both time and dose dependent and required the presence of cytochalasin B during stimulation. In contrast, activation by two nonchemotactic stimuli, the ionophore A23187 and phorbol myristate acetate (PMA), did not require cytochalasin B. Temporal patterns of oxidase activation suggested that different stimuli follow different transductional pathways. Chemoattractant-mediated activation was immediate (no lag); peaked by 45 s and declined rapidly to approximately 50% of maximal by 2 min. In contrast, activation by A23187 or PMA had a 15-30-s lag and increased more slowly. Stimulation by A23187 peaked at 5 min, then declined. Stimulation by PMA plateaued at 20 min and did not decline by 90 min. Comparison of Km values for NADPH and NADH obtained by Lineweaver-Burk analysis of the oxidase activity stimulated by N-formyl-methionyl-leucyl-phenylalanine, A23187, and PMA suggested that the same enzyme was activated by all stimuli. Thus, chemoattractants and other soluble stimuli appear to activate the same respiratory burst enzyme in PMN but they utilize different transductional mechanisms and are regulated differently. 相似文献