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61.
Dr. N. Tsukahara Dr. K. Toyama K. Kosaka 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1967,4(1):18-33
Summary Microelectrodes were inserted into the magnocellular portion of cat's red nucleus (RN), and some basic physiological properties of RN cells were examined by both extra- and intracellular recording. During stimulation of the rubrospinal fibres at the spinal segmental level, the RN cells were invaded antidromically, producing conspicuous field potentials within RN. The somatotopical distribution of RN cells was confirmed by comparing the field potentials induced from C2 and L1 levels. When recorded intracellularly, antidromic action potentials showed three-step configuration as those in motoneurones and were followed by a remarkable after-hyperpolarization. The conduction velocity along the rubrospinal fibres ranged from 41–123 m/sec, with the peak frequency at 91–100 m/sec. The membrane properties were examined in some RN cells by intracellular application of current steps. The total membrane resistance was 4 M on the average, and the membrane time constant 6 msec, respectively.Excitatory postsynaptic potentials (EPSPs) were induced monosynaptically in RN cells by stimulation of the nucleus interpositus of the contralateral cerebellum. Their time course was analyzed in comparison with that of the potentials produced by current steps. Stimulation in the ventrolateral nucleus of the thalamus evoked monosynaptic EPSPs via the collaterals of the interpositus axons which innervate RN and thalamus commonly. It was further shown that impulses in cortico-rubral fibres produced EPSPs in RN cells. These cerebral-evoked EPSPs were characterized by much slower time courses than those from the nucleus interpositus. 相似文献
62.
红细胞聚集与取向对其悬浮液电阻抗的影响——I.实验研究 总被引:1,自引:1,他引:1
本文通过测量具有不同流变特性的红细胞悬浮液电阻抗的动态与静态变化,研究了红细胞聚集与取向对其悬浮液电阻抗的影响。首次得出以下结论:1.红细胞聚集使其悬浮液电阻抗显著减小。2.由于低切变率下红细胞聚集与高切变率下红细胞取向的共同影响,使血液电阻抗随切变率的变化具有双相特性。这增加了对血液电特性的新认识,表明可利用电阻抗测定红细胞聚性。 相似文献
63.
Assessment of oestrogenic potency of chemicals used as growth promoter by in-vitro methods 总被引:7,自引:0,他引:7
Three in-vitro bioassays were used to compare the oestrogenic potency of chemicals used as growth promoter in beef cattle in certain non-European Union countries (17beta-oestradiol, alpha-zearalanol, testosterone, trenbolone, trenbolone acetate, melengestrol acetate) or found as food contaminant such as the mycotoxin zearalenone and some of their metabolites (17alpha-oestradiol, oestrone, 17alpha-epitestosterone, 19-nortestosterone, androstendione, zearalanone, alpha-zearalanol, beta-zearalanol, alpha-zearalenol, beta-zearalenol). The strong oestrogens 17alpha-ethinyl oestradiol and diethylstilboestrol were used as standards. The first bioassay was based on the activation of a reporter gene by oestrogens in recombinant yeast expressing human or rainbow trout oestrogen receptor. In the second bioassay, the vitellogenin gene induction of rainbow trout hepatocyte cultures was used as a biomarker for the exposure to oestrogens. The third bioassay was based on the alkaline phosphatase gene induction by oestrogens in the human endometrial Ishikawa cell line. The assessment of oestrogenic potency of these chemicals clearly demonstrates the strong oestrogenicity of the mycotoxin zearalenone and its metabolites and particularly alpha-zearalenol which was as potent as ethinyl oestradiol and diethylstilboestrol in the human endometrial Ishikawa cell line. 相似文献
64.
R. Kirsten E. Kirsten J. Wolff 《Pflügers Archiv : European journal of physiology》1969,307(3):154-166
Summary Since ether anesthesia lowered ATP by 25% in red, but not in white muscle, and only when the spinal neurones were intact, we suggested that small or intermediate muscle units were activated under ether anesthesia [8].In order to prove this postulate, some glycolytic metabolites, known to rise under muscular activation, are studied in the white musculus adductor magnus and in the red musculus pyramidalis of the rat: glucose-1-phosphate, glucose-6-phosphate, fructose-6-phosphate, fructose-1-6-diphosphate, -glycerophosphate, lactate, pyruvate, and dihydroxyacetone phosphate.The conditions compared are: Inactin (5-ethyl-5(methyl-propyl)-2-thiobarbituric acid)-anesthesia, diethyl ether anesthesia, and tetanic contraction under Inactin anesthesia.The histological assay with Sudan-black B staining shows 34.2±7.3% dark fibers in m. pyramidalis and 0.2±4.8% dark fibers in m. adductor magnus.Glucose-1-phosphate, fructose-1-6-diphosphate, and -glycerophosphate are elevated under ether anesthesia in both muscles versus Inactin anesthesia by 100–200%.Lactate in both muscles and pyruvate in the red muscle are slightly elevated under ether (by 40%) versus Inactin anesthesia.Under tetanic contraction the metabolites studied rise considerably in both muscles.As glycogen is lowered in rat muscle under ether [9], the present results suggest an activation of glycogen phosphorylase and of phosphofructokinase in both the red and the white muscle under ether anesthesia, which results in augmented glycolysis.The comparatively small increment of pyruvate and lactate in the presence of a high increment of -glycerophosphate under ether anesthesia is considered to indicate an asynchronous activation of fibers with unimpaired circulation and oxidative metabolism. 相似文献
65.
Rainer Amann Carlo Alberto Maggi Sandro Giuliani Josef Donnerer Fred Lembeck 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(6):534-537
Summary In the superfused isolated rat urinary bladder, capsaicin as well as electrical field stimulation evoked the release of calcitonin gene-related peptide-like immunoreactivity (CGRP-IR). Carbonyl cyanide p-trichloromethoxyphenylhydrazone (CCCP, threshold 2 M) reduced both, the capsaicin- and the electrical field stimulation-evoked release of CGRP-IR while a low concentration of Ruthenium Red (RR, 0.6 M and 2 M) selectively attenuated the capsaicin-evoked release of CGRP-IR but did not influence the effect of electrical field stimulation. 20 M RR nearly abolished the capsaicin-evoked release, but also attenuated the effect of electrical field stimulation.In the isolated guinea-pig bronchus, electrical field stimulation and capsaicin induced non-cholinergic contractions which are known to be caused by tachykinin release from afferent nerve terminals. CCCP (0.6 M) only reduced the response to field stimulation; a ten-fold higher concentration of CCCP attenuated field stimulation as well as capsaicin-induced contractions. This is in contrast to the reported selective inhibition of capsaic-ininduced contractions by RR.The present data demonstrate that CCCP generally inhibits evoked neuropeptide release, regardless of the kind of stimulation used while low concentrations of RR preferentially inhibit capsaicin-evoked neuropeptide release.Send offprint requests to: R. Amann at the above address 相似文献
66.
何良新 《中国自然医学杂志》2000,2(4):216-217
目的 了解导赤散加味对慢性前列腺炎的疗效。方法 应用导赤散为主组方,结合直肠指诊、化验检查进行综合分析,辨证加减用药、治疗慢性前列腺炎110例,并与口服环丙沙星片、回通淋丹组40例作对照。结果 治疗组近期治愈率36.4%,总有效率为91.0%,对照组近期治愈率仅15.0%,总有效率为72.5%,两组的有效率比较差异有显性(P<0.05)。结论 导赤散加味治疗慢性前列腺炎有明显改善作用。 相似文献
67.
摘要:目的:观察虫对慢性血瘀型大鼠血液流变性和红细胞免疫功能的影响。方法:模拟阴虚火旺复制慢性血瘀大鼠模型,用毛细血管法测定不同切速下的全血比粘度、血浆比粘度,常规法测定红细胞压积。参照郭氏法测定红细胞免疫粘附功能指标,并将其与血液流变性有关指标作一相关分析。结果:虫能明显降低瘀血大鼠的全血比粘度、血浆比粘度和红细胞压积;提高瘀血大鼠红细胞C3b受体花环率,使红细胞免疫复合物花环率下降,血清红细胞免疫粘附促进因子活性增强,而抑制因子减弱;血液粘度与红细胞C3b受体花环率的相关分析呈显著负相关。结论:虫不仅有活血化瘀作用,还具有促进红细胞免疫功能的功效。 相似文献
68.
枸杞多糖对小鼠红细胞免疫功能的影响 总被引:10,自引:0,他引:10
目的 研究枸杞多糖 (LBP)对小鼠红细胞免疫功能的影响。方法 用形态学方法测定LBP对正常小鼠及环磷酰胺 (CY)造成的免疫抑制小鼠的红细胞C3 b受体 (RBC -C3 bR)花环率和红细胞免疫复合物 (RBC -IC)花环率的影响。结果 LBP能明显增强正常小鼠RBC -C3 bR花环率及RBC -IC花环率 ,并能使CY(2 5mg/kg× 3次 )引起下降的RBC -C3 bR花环率及RBC -IC花环率显著回升。结论 LBP能增强小鼠红细胞免疫功能 ,并对CY所致的红细胞免疫功能的抑制具有明显的拮抗作用 相似文献
69.
Baek NI Kim JM Park JH Ryu JH Kim DS Lee YH Park JD Kim SI 《Archives of pharmacal research》1997,20(3):280-282
A genuine dammarane-glycoside, named as ginsenoside Rs3, was isolated from the MeOH extracts of Korean red ginseng (Panax ginseng C.A. Meyer) through repeated silica gel column chromatographies and its chemical structure was determined as (20S)-protopanaxadiol 3-O-[6″-O-acetyl-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside on the basis of several spectral and physical evidences including HMBC
and FAB-MS. 相似文献
70.
Comparison of non-invasive approaches to red marrow dosimetry for radiolabelled monoclonal antibodies 总被引:1,自引:0,他引:1
Marian A. B. D. Plaizier Jan C. Roos Gerrit J. J. Teule Erik B. van Dieren Wim den Hollander Hidde J. Haisma Robert L. DeJager Arthur van Lingen 《European journal of nuclear medicine and molecular imaging》1994,21(3):216-222
Red marrow is usually the dose-limiting organ during radioimmunotherapy. Several non-invasive approaches to calculate the red marrow dose have been proposed. We compared four approaches to analyse the differences in calculated red marrow doses. The data were obtained from immunoscintigraphy of two antibodies with different red marrow kinetics [iodine-131-16.88 IgM and indium- 111-OV-TL-3 F(ab)2]. The approaches are based on, respectively, homogeneously distributed activity in the body, a red marrow-blood activity concentration ratio of 0.3, scintigraphic quantification, and a combination of the second and third approaches. This fourth approach may be more adequate because of its independence from the chosen antibody. In addition, the influence of activity accumulation in liver, kidneys or cancellous bone on red marrow dose was studied. The calculated red marrow dose varied between 0.14 and 0.42 mGy/MBq for 111 In-OV TL-3 and between 0.13 and 0.68 mGy/MBq for 131I-16-88. If the radiopharmaceutical shows high affinity for cancellous bone or another organ situated near the red marrow, the activity in these organs must be included in dose calculations. This study shows a large variation in calculated red marrow dose and selection of the definitive non-invasive approach awaits validation.
Correspondence to: M.A.B.D. Plaizier 相似文献