全文获取类型
收费全文 | 286篇 |
免费 | 15篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 12篇 |
妇产科学 | 2篇 |
基础医学 | 45篇 |
口腔科学 | 7篇 |
临床医学 | 54篇 |
内科学 | 46篇 |
皮肤病学 | 9篇 |
神经病学 | 9篇 |
特种医学 | 18篇 |
外科学 | 30篇 |
综合类 | 30篇 |
预防医学 | 15篇 |
眼科学 | 4篇 |
药学 | 5篇 |
中国医学 | 6篇 |
肿瘤学 | 8篇 |
出版年
2022年 | 2篇 |
2021年 | 8篇 |
2020年 | 5篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 11篇 |
2013年 | 11篇 |
2012年 | 10篇 |
2011年 | 7篇 |
2010年 | 14篇 |
2009年 | 13篇 |
2008年 | 8篇 |
2007年 | 14篇 |
2006年 | 9篇 |
2005年 | 9篇 |
2004年 | 8篇 |
2003年 | 9篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 9篇 |
1999年 | 7篇 |
1998年 | 7篇 |
1997年 | 10篇 |
1996年 | 15篇 |
1995年 | 7篇 |
1994年 | 3篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1971年 | 2篇 |
1964年 | 1篇 |
1959年 | 1篇 |
1954年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有306条查询结果,搜索用时 0 毫秒
81.
Anoxia and inhibitors of energy metabolism have been studied for their effect on intracellular K and Na concentrations, membrane potential, conductivity, passive and active ouabain-sensitive transport of potassium (86Rb) in neurons of freshwater snail Planorbarius corneus. The X-ray microanalysis has shown that anoxia caused no changes in K and Na concentrations in neurons. NaCN inhibited oxygen uptake by ganglia, but has actually no effect on the membrane potential, conductivity and 86Rb uptake in neurons. Much stronger inhibition of the 86Rb uptake was observed in the presence of 2-deoxy-D-glucose. When both glycolytic and respiratory inhibitors were added, the effect was maximal. It is supposed that glycolysis is the main source of energy to maintain the ion homeostasis in the mollusc neurons. 相似文献
82.
V G Medvedev D M Kulibaba L P Pivovarova 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1992,(11):7-9
In 165 patients with the different forms of cholelithiasis, a level of the circulating immune complexes (CIC) was measured in the blood serum and bile from the common bile duct at the postoperative period. In associated purulent-resorptive and cholemic intoxication, the CIC level in the blood serum and bile increases. This, in turns, enhances the likelihood of the development of purulent-septic complications at the postoperative period, and requires performance of target immunocorrection. 相似文献
83.
The physiological importance of prostaglandin E2 (PGE2) biosynthesis in the gastric mucosa is unknown. A role of endogenous prostaglandins in protecting the gastrointestinal epithelia has been suggested, but the evidence is unsufficient and rarely supported by concomitant measurement of PG production. Amounts of PGE2 in luminal gastric contents which can be sampled atraumatically may reflect PGE2 synthesis in the gastric mucosa in vivo. To confirm earlier reported measurements made with radioimmunoassay we have measured by gas chromatography - mass spectrometry (GC-MS) PGE2 in gastric juice of five healthy men under basal conditions and during stimulation of muscarinic receptors with iv. bethanechol which in dog is reported to enhance PGE2 output. PGE2 was detected in all basal samples. The output was in median 32.1 pmol/15 min (range 17.0–105.4, 1 pmol=0.352 ng), which is similar to results from earlier studies. Bethanechol infusion (60 μg x kg-1 x h-1) did not affect PGE2 outputs systematically in spite of a significant increase in outputs of acid and chlorides. Stimulation of muscarinic receptors does not seem to influence PGE2 synthesis in gastric mucosa in vivo. Alternatively changes in PGE2 synthesis may be masked by rapid chemical or enzymatical degradation or reabsorption of PGE2.Studies are under way to explore those phenomena. 相似文献
84.
SVEND-AAGE JOHNSEN AGNETHA OLOFSSON KRISTER GREN LARS B. OLDING 《American journal of reproductive immunology (New York, N.Y. : 1989)》1983,4(1):45-49
ABSTRACT: We have tested peripheral mononuclear leukocytes (PML) from the cord blood of newborns, from sera of their mothers, and from sera of nonrelated nonpregnant adult women for sensitivity to suppressive exogenous prostaglandin E2 (PGE2). Endogenous PG production was simultaneously inhibited by indomethacin 2.8 μM. The phytohemagglutinin-stimulated (PHA-stimulated) uptake of tritiated thymidine (3H-TdR) by PML from the mothers and the nonpregnant women was suppressed by the exogenous PGE2 at a concentration of 1.4 × 10?8 M, 100 times less than the one required to suppress the PML from newborns (1.4 × 10?6 M). In addition, 1.4 × 10?7 M or less of PGE2 reversed the suppression of neonatal PML to stimulation. The maternal PML were reversed into stimulation at 1.4 × 10?9 of exogenous PGE2. The amount of endogenous PGE2 synthesized by 1 × 106 fresh, nonstimulated neonatal PML according to gas chromatography-mass spectrometry assay was 5 ng (1.4 × 10?8 M). The synthesis increased to 27 ng/106 cells after 18 hours' incubation. These concentrations are similar to the ones of exogenous PGE2 at which neonatal PML were slightly stimulated but the maternal cells were still suppressed. Preincubation for 18 h at 37°C decreased the PGE2-induced suppression of the adult PML but did not change the response of the neonatal PML. 相似文献
85.
1.锑胺羧螯合物是一种新型的抗肿瘤药物,应用Sb-26(EDTA-SbNa)、Sb-57(PDTA-SbNa)、Sb-66(HEDT-Sb)和Sb-71(ATA-Sb)分别为15—20、30—50、25—30和20—40毫克/公斤剂量时,均能显著地抑制小白鼠Ehrlich 腹水瘤的生长,平均延长生存时间4—22天,延长率36—147%.上述剂量对大白鼠Guerin 氏癌也有抑制作用,抑制率为58—70%.后3个药物,还能使小白鼠梭形细胞肉瘤腹水型的生存时间延长5—16天,延长率50—160%,其中以Sb-71的疗效最著.Sb-26、Sb-57、Sb-71、Sb-66对肉瘤180和AK 肉瘤及前3者对Ehrlich 固体瘤和淋巴白血病固体型的实验结果,除Sb-71对肉瘤180有抑制作用外,其他均无疗效.2.4 类锑化合物:3个(月弟)酸化合物(Sb-8,Sb-11和Sb-42)及1个酒石酸锑(Sb-15),与螯合的间苯二酚锑(Sb-64)和8羟基喹啉锑(Sb-85)各1个,对Ehrlich 腹水瘤的实验结果,均无明显疗效.3.小白鼠的急性半数致死量,Sb-57和Sb-71分别为131和62毫克/公斤,亚急性半数致死量分别为75和58毫克/公斤. 相似文献
86.
Neutrophil chemotaxis and random migration were studied in 65 healthy children and 18 normal adults. The method used, the leading-front technique, was more accurate and reproducible than the lower surface count method. Chemotaxis in children under 15 years differed from that in adults. This age effect was most pronounced in those less than 6 years, and particularly in those less than 2 years. When investigating chemotaxis in childhood, comparisons with age-matched controls should be made. 相似文献
87.
88.
89.
同时测定乌梅中8种有机酸含量 总被引:3,自引:0,他引:3
目的:建立RP-HPLC同时测定乌梅中8种有机酸成分:草酸、酒石酸、苹果酸、抗坏血酸、乳酸、醋酸、柠檬酸和琥珀酸。方法:在C18柱上,用(NH4)H2PO4-H3PO4水溶液(pH 2.8)作流动相,紫外检测器检测(214 nm),流动相流速为0.5 mL·min-1。结果:分别建立了8种有机酸成分的回归方程。草酸、酒石酸、苹果酸、抗坏血酸、乳酸、醋酸、柠檬酸和琥珀酸的含量分别为1.29%,0.36%,1.82%,1.82%,2.09%,1.65%,16.0%,3.09%。结论:该方法操作简便,准确,快速,一次测定不超过10 min;不但可以作为中药乌梅有机酸成分的质量分析,也可用作为其他植物中有机酸的定量分析。 相似文献
90.
高血压脑出血血肿周围组织血-脑屏障变化的动态观察 总被引:18,自引:0,他引:18
目的动态观察高血压脑出血血肿周围组织血-脑屏障的变化.方法对6例高血压脑出血患者实施立体定向血肿碎吸术,术中取血肿周围少许脑组织进行超微病理观察.结果血-脑屏障的损伤与出血时间的长短呈正比.脑出血后24h,可见星形胶质细胞肿胀,部分细胞崩解、坏死.毛细血管周围细胞足突肿胀,血-脑屏障损坏.72h,部分星形胶质细胞高度肿胀,细胞器溶解.毛细血管内皮细胞胞核增大,胞质突入管腔,内皮细胞间紧密连接消失.4~7d,星形细胞高度肿胀,胞质内充满水肿液,细胞器消失,细胞变性.毛细血管星形细胞足突明显肿胀,血管周围可见微小出血灶.结论血-脑屏障的变化与患者的预后有密切关系. 相似文献