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991.
软组织平滑肌肉瘤中p16基因的甲基化检测 总被引:2,自引:2,他引:2
目的 探讨软组织平滑肌肉瘤(LMS)中p16基因INK4A的甲基化状态及其与p16表达的关系。方法 应用MSP法检测38例软组织平滑肌肉瘤,10例平滑肌瘤及5例正常平滑肌组织中p16基因INK4A的甲基化状态,用免疫组织化学SP方法检测p16蛋白表达情况。结果 38例LMS中9例发生异常甲基化,异常甲基化率为23.7%(9/38)。其中,7例p16蛋白表达阴性,2例p16蛋白弱阳性,在p16蛋白表达阴性的LMS中,异常甲基化率为50%(7/14)。结论 p16基因第一外显子启动子区5‘CpG岛的异常甲基化是导致p16基因失活、蛋白缺如的重要基因外机制,并可能参与肿瘤的发生。 相似文献
992.
本文报导混合浓缩人血清工作标准(89-1)的制备和用WHO相应参考标准血清标定出其中五类免疫球蛋白(Igs)及IgG4亚类含量。该制剂主要用于体外测定IgG、IgA、IgM的工作标准,也可供作体外测定IgD、IgE、IgG4的工作标准。混合前每份血清均无乙型肝炎表面抗原、转氨酶正常。定量分装为每安瓿0.5ml,经冷冻干燥后,4℃保存。参照国际参考标准血清67/97及67/37,分别以免疫单扩散法标定89-1中IgG、IgA、ISM含量;以酶联免疫吸附试验(ELISA)标定IgD、IgG4和IgE含量。其中IgG、IgG4、IgA、IgM含量,应用本室制备的相应单克隆抗体(McAb)标定,而IgD和IgE应用多克隆抗体(PcAb)进行标定。并用五剂量法及四剂量法分别计算Igs含量。 相似文献
993.
M. Toselli Patrizia Tosetti Vanni Taglietti 《Pflügers Archiv : European journal of physiology》1997,433(5):587-596
Ca2+ channel modulation by the μ opioid agonist [d-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAGO) and the δ opiate agonists [d-Pen2, d-Pen5]-enkephalin (DPDPE) and [d-Ala2, d-Leu5]-enkephalin (DADLE) in cultured human neuroblastoma SH-SY5Y cells was investigated using the whole-cell variant of the patch-clamp
technique. In SH-SY5Y cells, differentiated in vitro with retinoic acid, all agonists reversibly decreased high-voltage-activated,
ω-conotoxin-sensitive Ba2+ currents in a concentration-dependent way. Inhibition was maximal with a 1 μM concentration of opiate agonists (76% with DAGO
and 63% with δ agonists, when measured at 0 mV) and was characterized by a clear slow down of Ba2+ current activation at low test potentials. Both inhibition and slow down of activation were attenuated at more positive potentials,
and could be partially relieved by strong conditioning depolarizations. Current suppression operated by both μ and δ agonists
was prevented by pre-treatment of the cells with pertussis toxin. No sign of additivity was observed when δ agonists were
applied to cells that were maximally activated by DAGO, suggesting that a common mechanism, involving the same type of modulating
molecule, is responsible for Ca2+ channel inhibition promoted by activation of μ and δ opioid receptors in SH-SY5Y cells.
Received: 10 October 1996 / Received after revision and accepted: 18 November 1996 相似文献
994.
Intragastric infusion of amino acids causes the release from the liver of a factor with stimulatory effect on smooth muscle. The effect of liver vein plasma ultrafiltrate was tested on isolated preparations of rat fundus. The ultrafiltrates collected after amino acid infusion had a 3–5 times higher stimulatory effect on smooth muscle contraction than those collected from control plasma. The active principle was isolated, purified by different chromatographic procedures and identified as 5–hydroxytryptamine (serotonin). No other compound with contractile effect on smooth muscle was detected. 相似文献
995.
In order to gain insight into the process of colonization of the bowel by the neural crest-derived precursors of enteric neurons, the development of the enteric nervous system was examined in lethal spotted mutant mice, a strain in which a segment of bowel is congenitally aganglionic. In addition, nerve fibers within the ganglionic and aganglionic zones of the gut of adult mutant mice were investigated with respect to their content of acetylcholinesterase, immunoreactive substance P, vasoactive intestinal polypeptide and serotonin, and their ability to take up [3Hserotonin. In both the fetal gut of developing mutant mice and in the mature bowel of adult animals abnormalities were limited to the terminal 2 mm of colon. The enteric nervous system in the proximal alimentary tract was indistinguishable from that of control animals for all of the parameters examined. In the terminal bowel, the normal plexiform pattern of the innervation and ganglion cell bodies were replaced by a coarse reticulum of nerve fibers that stained for acetylcholineserase and were continuous with extrinsic nerves running between the colon and the pelvic plexus. These coarse nerve bundles contained greatly reduced numbers of fibers that displayed substance P- and vasoactive intestinal polypeptide-like immunoreactivity, but a serotonergic innervation was totally missing from the aganglionic bowel. During development, acetylcholineserase and uptake of [3Hserotonin appeared in neural elements in the foregut of mutant mice on the 12th day of embryonic life (E12), about the same time these markers appeared in the forgut in normal mice. By day E14, neurons expressing one or the other marker were recognizable as far distally as about 2 mm from the anus. The appearance of neurons in segments of gut grown for 2 weeks as expiants in culture was used as an assay for the presence of neuronal progenitor cells in the segments of fetal bowel at the time of explantation. Both acetyl- cholinesterase activity and uptake of [3Hserotonin developed in neuronsin vitro in expiants of proximal bowel between days E10 and E17. At all times, however, the terminal 2mm of mutant but not normal fetal gut gave rise to aneuronal cultures. In some mutant mice rare, small, ectopically-situated pelvic ganglia were found just outside aganglionic segments of fetal colon. Uptake of [3Hserotonin, normally a marker for intrinsic enteric neurites, was found in these ganglia.The experiments suppport the hypothesis that the terminal 2 mm of the gut in lethal spotted mutant mice is intrinsically abnormal and thus cannot be colonized by the precursors of enteric neurons. The defect seems to be specific in that both cells and processes of intrinsic enteric neurons, including all serotonergic and most peptidergic neurites, seem to be excluded from the abnormal region while extrinsic nerve fibers, including sympathetic and sensory axons, are able to enter the aganglionic zones. Since examination of neural progenitor cells has failed to reveal a significant proximo-distal displacement of these cells through the enteric tube during development of the murine bowel, a defect in the migration of precursor cells down the alimentary tract to the terminal gut seems unlikely to be substantially involved in the pathogenesis of aganglionosis. This conclusion is supported by the normal enteric nervous system in proximal regions of the mutant gut and the presence of enteric type neurons outside of, but at the same level as the aganglionic region. 相似文献
996.
In cat hypoglossal motoneurons after axotomy the synaptic efficacy of inhibitory synapses made by the lingual nerve afferent fibers was studied. The amplitude of the short- and the long-lasting inhibitory postsynaptic potential produced in tongue protruder motoneurons 24 days after axotomy by stimulation of the lingual nerve was significantly reduced in size as compared with the control on the unoperated side. In most protruder motoneurons 40 days after axotomy a large excitatory postsynaptic potential and a spike was produced by stimulation of either the ipsilateral or the contralateral lingual nerve. We have demonstrated that the decline of synaptic efficacy of inhibitory synapses for the short-lasting inhibitory postsynaptic potential was more prominent than that for the long-lasting inhibitory potential in the motoneuron 24 days after axotomy. After the cut axons of protruder motoneurons were re-united to tongue muscles, we have demonstrated that the decline of synaptic efficacy of inhibitory synapses for the short-lasting inhibitory postsynaptic potential was less prominent than that in axotomized protruder motoneurons. 相似文献
997.
A method is described for the simultaneous detection of radiolabelled bone marrow cells bearing surface immunoglobulins by combined autoradiography and immunoperoxidase. Bone marrow cells from normal CBA mice prelabelled in vivo with 125IUDR or exposed in vitro to [3H]thymidine were incubated with rabbit anti-mouse immunoglobulins under capping conditions, washed, cytocentrifuged and treated with methanol and hydrogen peroxide to destroy endogenous peroxidase. Cells were then covered with peroxidase-conjugated goat anti-rabbit immunoglobulins, washed, treated with diaminobenzidine a and hydrogen peroxide and finally covered with autoradiographic stripping film and exposed for different times. Peroxidase-positive cells were typically capped and those radiolabelled had autoradiographic silver grains overlying the nucleus. 相似文献
998.
Both papain-solubilized and detergent-solubilized human histocompatibility antigens have been treated with NTCB (2-nitro-5-thiocyanatobenzoic acid) which cleaves these molecules at cysteine residues. A study of the fragment produced has made it possible to deduce the size and location of the two disulfide loops in these molecules. The sizes of the two loops in HLA-B7 and in the mixture HLA-B7 + 12 are about 5100 and 6600 daltons, a size similar to that of the disulfide loops found in immunoglobulins. The disulfide loops in HLA-A2 may be smaller in size. The two loops are located in middle regions of these molecules; neither the N-terminal nor the C-terminal regions contain disulfide loops. 相似文献
999.
V. P. Komissarenko I. S. Chelnakova A. S. Mikosha 《Bulletin of experimental biology and medicine》1978,85(2):152-154
o,p-Dichlorodiphenyldichloroethane (o,p-DDD) and Perthane, when added in a concentration of 312 M to homogenate and cytoplasmic fraction of dog adrenals, activate glutathione reductase. In a concentration of 156 M, o,p-DDD and Perthane do not affect glutathione reductase activity of the dog adrenals. When given in vitro, o,p-DDD and Perthane activate glutathione reductase of the guinea pig adrenals. o,p-DDD has no effect on glutathione reductase activity of the cytoplasmic fraction of dog liver and kidney, thus confirming the high specificity of its effect on the adrenal cortex.Laboratory of Pathophysiology, Institute of Endocrinology and Metabolism, Kiev. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 159–161, February, 1978. 相似文献
1000.
A Sprague-Dawley rat model with DS sarcoma transplanted in the thigh was used to compare transcatheter locoregional i.a. and systemic i.v. administration of 5-fluorouracil (FU) at 12 dose-rate schedules: 25, 50 and 100 mg/kg; bolus, 1, 5 and 24 h infusions. In experiment A tumor (62/67 animals) as well as liver and kidney (56/67 animals) were excised 1 h after a single bolus or 1 h infusion or at the end of 5 and 24 h infusions. (19)F-NMR spectroscopy at 11.7 T was used to quantitate FU and its metabolites in ca. 1 g of tissue at 4 degrees C. In experiment B analogous FU treatments were repeated for 5 days (rats 80+11 controls). Tumor volumes vs time, various blood parameters and survival times were recorded, and a log growth rate parameter log GR, a response index RI, and a toxicity index TI were calculated. The i.a. vs i.v. ratios for tumor concentrations of FU and total anabolites (F-Nucl) were >1 for nearly all treatments and increased with infusion time at the higher doses. F-Nucl in tumor correlated linearly with total fluorine concentration (Tot. F range 30-1100 nmol/g) over all treatments (r=0.92, slope=0.45, p<0.0001). For non-bolus i.v. treatments [FU+F-Nucl] decreased linearly with decreasing FU dose rate (r(2)=0.74, zero intercept), while i.a. treatments showed non-linear behavior. For non-bolus treatments the mean log GR per treatment group showed a negative correlation (r=-0.87) with log[F-Nucl]. The most effective non-toxic treatments were 25 mg/kg over 5 or 24 h; the i.a. route was superior to i.v. on the basis of [FU+F-Nucl], RI, the reduction in log GR, and Kaplan-Meier survival statistics. For liver and kidney Tot. F (>83% FU catabolites) reached ca. 3-4 and 6-7 micromol/g, respectively, at the highest dose rates for either route; F-Nucl were detected only for Tot. F>500 nmol/g and increased exponentially as Tot. F increased (toxic treatments). The concentrations of the main catabolite (alpha-fluoro-beta-alanine, FBAL) in tumor did not correlate with Tot. F but rather with FBAL levels in kidney (r=0.90, all treatments), indicating that uptake of liver-derived FBAL from the circulation is the major source of FBAL in tumor. 相似文献