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991.
阿托品对兔局部脑缺血Ca2+积累和细胞水肿的作用 总被引:1,自引:0,他引:1
阿托品对兔局部脑缺血Ca2+积累和细胞水肿的作用吕爱刚胡香杰贾丹辉张贵卿可君(河南医科大学药理学教研室,郑州450052)阿托品(atropine,Atr)为一典型的M受体阻断剂,近年研究表明它可以选择性对抗KCl和CaCl2对兔基底动脉收缩作用,其... 相似文献
992.
993.
Abstract. Erythrocyte sodium-lithium countertransport (SLC) activity, membrane fluidity, plasma trigly-ceride and cholesterol were measured in hyperlipidaemic patients and normal subjects. Fluidity was assessed by the fluorescence anisotropy (inversely related to fluidity) of the probes 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1,4-trimethylammonium-3,5-hexatriene (TMA-DPH). In a second group of patients the maximum velocity (Vmax) and external sodium affinity constant (km ) of SLC was also measured.
In the first group of patients, SLC activity was increased compared with the controls (0.279 ± 0.019 vs. 0.213 ± 0.013, P = 0.006) as was membrane fluidity in the deep hydrophobic regions (DPH anisotropy 0.211 ± 0.0007 vs. 0.215 ± 0.0011, P = 0.007). There was a strong correlation between SLC and DPH anisotropy (Rs= -0.72, P= < 0.001) which was due to the correlation between Vmax and DPH anisotropy (Rs=-0.90, P= < 0.001).
Increases in Vmax of SLC in hyperlipidaemic patients may be due to differences in lipid organisation in the deep hydrophobic regions of the membrane which may affect the turnover rate of the transporter. 相似文献
In the first group of patients, SLC activity was increased compared with the controls (0.279 ± 0.019 vs. 0.213 ± 0.013, P = 0.006) as was membrane fluidity in the deep hydrophobic regions (DPH anisotropy 0.211 ± 0.0007 vs. 0.215 ± 0.0011, P = 0.007). There was a strong correlation between SLC and DPH anisotropy (Rs= -0.72, P= < 0.001) which was due to the correlation between Vmax and DPH anisotropy (Rs=-0.90, P= < 0.001).
Increases in Vmax of SLC in hyperlipidaemic patients may be due to differences in lipid organisation in the deep hydrophobic regions of the membrane which may affect the turnover rate of the transporter. 相似文献
994.
ANTEROVENTRAL WALL OF THE THIRD VENTRICLE AND DORSAL LAMINA TERMINALIS: HEADQUARTERS FOR CONTROL OF BODY FLUID HOMEOSTASIS? 总被引:3,自引:0,他引:3
MJ McKinley GL Pennington BJ Oldfield 《Clinical and experimental pharmacology & physiology》1996,23(4):271-281
1. The subfornical organ, median preoptic nucleus and the organum vasculosum of the lamina terminalis (OVLT) are a series of structures situated in the anterior wall of the third ventricle and form the lamina terminalis. The OVLT and ventral part of the median preoptic nucleus are part of a region known as the anteroventral third ventricle region.
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation. 相似文献
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation. 相似文献
995.
EffectsoftetrodotoxinmonoclonalantibodyontheblockingactionoftetrodotoxinonsodiumchannelsDuAimin;SongJiejun;XingBaoren;ShenZhi... 相似文献
996.
李日照 《中国医药工业杂志》1988,(10)
将(±)-酒石酸制成其钠铵盐,在27℃以下进行诱导拆分,得(+)-和(-)-酒石酸钠铵,经转化为钙盐,再处理精制可得合格的(+)-和(-)-酒石酸。总收率为91%以上。 相似文献
997.
瓜蒌皮抗缺氧作用的研究 总被引:15,自引:0,他引:15
实验结果显示,瓜蒌皮提取液(EPT)腹腔注射40 g·kg-1能明显延长常压缺氧、组织缺氧、特异性心肌缺氧小鼠的存活时间,延长率分别为 145%, 2.79%, 110.7%,使减压缺氧小鼠的存活率达85%.表明瓜蒌皮确能增强整体动物的抗缺氧能力. 相似文献
998.
Abstract Osmotically balanced solutions of glucose (0.5–300 mM) and sodium chloride, containing surfactants, were instilled into the small or large intestine of anaesthetized rats. Net absorption or secretion of glucose, sodium and potassium was studied. The surfactants tested were dodecylsulphate (3.4–17 mM), dioctyl-sulphosuccinate (1.8–11 m/M), Lubrol WX (0.1–0.5%), Triton × 100 (0.25%) and desoxycholate (2.5 mM). Qualitatively, the results were similar to those obtained previously with cationic compounds, suggesting a common mode of action for all surfactants studied. 17 mM dodecylsulphate seemed to abolish completely physiological glucose transport in the jejunum and ileum. At a lower concentration, and with the other surfactants, normal glucose transport was affected to an intermediate extent. 相似文献
999.
K Foster-Smith B E Leonard 《Progress in neuro-psychopharmacology & biological psychiatry》1985,9(4):361-367
There was no overt evidence of the development of physical dependence, as shown by a decrease in the body weight of rats following the abrupt withdrawal of dextropropoxyphene after two weeks administration. The ambulation and rearing scores in the 'open field' apparatus were increased after chronic, but not acute drug administration and returned to control values two days following drug withdrawal. GABA turnover, determined from the rise in GABA concentrations following GABA-transaminase inhibition, was reduced in the frontal and amygdaloid cortex after acute and chronic drug administration; a compensatory rise in GABA turnover in the amygdaloid cortex occurred two days after drug withdrawal. Na+, K+, ATP'ase activity, determined in a synaptosomal fraction from the mid-brain and hippocampus, was decreased in the latter region only during drug administration; a compensatory increase in the activity of this enzyme was found two days after drug withdrawal. These results support the view that chronically administered dextropropoxyphene may cause changes in inhibitory transmission and central neurotransmitter transport. 相似文献
1000.
Trichomonas vaginalis avidly bound numerous host macromolecules which were not removed by repeated washing in phosphate buffered saline. The use of radioiodinated Cohn plasma fractions in binding studies allowed the identification of plasminogen, fibrinogen, immunoglobulin G, lipoproteins A and B, transferrin, α1-antitrypsin, and albumin on intact organisms. The binding of immunoglobulin G, albumin, transferrin, and lipoproteins to intact, motile trichomonads was further demonstrated using 125I-labeled plasma that was chromatographically depleted of these proteins. Kinetic studies indicated that 125I-labeled lipoproteins bind to T. vaginalis in a receptor-ligand-like manner. The surface localization and uptake of bound lipoproteins was shown by treatment of intact organisms with pronase at various times after incubation with lipoproteins. Purified lipoproteins could be substituted for plasma or serum as a growth supplement in a complex medium of trypticase/yeast extract/maltose and supported growth and multiplication rates equal to those in the same medium with plasma. 相似文献