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991.
A case of a 42 year old multiparous female with bilateral angiosarcoma of the breast without any evidence of dissemination, who later also developed a psammomatous meningioma, is described herein. The world literature on angiosarcoma is reviewed and a discussion presented on the incidence of bilaterality, hormonal stimulation, diagnostic difficulty, prognostic factors and treatment modalities.  相似文献   
992.
石斛类叶鞘的显微鉴定研究   总被引:2,自引:0,他引:2  
商品石斛的植物来源复杂,规格繁多,外形鉴定较困难。为了准确鉴定石斛的品种,对常作为药用的16种石斛属(Dendrobium Sw)植物的叶鞘进行了显微观察,发现其表皮细胞的形状,大小,所含草酸钙结晶的形状、大小、分布等种间区别较明显,可作为鉴别石斛种类的科学依据之一。本文对金钗石斛D.nobile Lindl。等16种石斛的叶鞘表面特征加以描述,并附主要特征图和检索表。  相似文献   
993.
动物组织膜L-维生素C电极的研究   总被引:2,自引:0,他引:2  
本文以猪肝组织切片偶合氧电极制成了维生素C生物电极。测试了电极的响应特性,当Cu2+)离子存在下,在21.14~352.3μg/ml的维生素C浓度范围,电极的动力学响应与维生素C浓度的对数呈线性关系。研究了激活剂的浓度、缓冲介质、温度等因素对电极性能的影响。测得该条件下酶促反应的米氏常数8.0×10-4mol/L。将电极用于药物中Vc含量分析,结果令人满意。  相似文献   
994.
Murphy  MF; Metcalfe  P; Waters  AH; Ord  J; Hambley  H; Nicolaides  K 《Blood》1993,81(8):2174-2179
In feto-maternal alloimmune thrombocytopenia (FMAIT), severe hemorrhage, particularly intracranial haemorrhage (ICH), may occur before delivery. Management strategies to prevent ICH in high-risk pregnancies include maternal administration of intravenous Ig with or without steroids and fetal platelet transfusions. This report describes a patient who lost three fetuses with ICH because of FMAIT due to anti- HPA-1a. ICH occurred earlier in successive pregnancies (at 28, 19, and 16 weeks of gestation) despite maternal treatment with intravenous Ig and steroids from 14 weeks of gestation in the third pregnancy. The fourth pregnancy was managed by administering weekly intraperitoneal injections of Ig to the fetus from 12 to 18 weeks of gestation. At 18 weeks, there was no evidence of ICH, but the fetal platelet count was only 12 x 10(9)/L. Serial fetal platelet transfusions were started, but there were poor responses because of immune destruction of the transfused platelets by maternal HLA antibodies. There were improved responses to transfusions prepared from the mother and from HLA- compatible HPA-1a-negative donors. At 35 weeks of gestation, a normal infant was delivered by Caesarean section after 20 platelet transfusions. There was prolonged thrombocytopenia in the baby for 15 weeks after birth, probably due to transfer of HPA-1a antibodies in the transfusions of unwashed maternal platelets. The optimal management of pregnancies likely to be severely affected by FMAIT is still evolving. Intensive management was successful in this case, but a successful outcome cannot be guaranteed in severely affected cases. This is the first time that HLA incompatibility has been found to complicate fetal transfusion therapy.  相似文献   
995.
A patient who wished to be treated for infertility by intracytoplasmic sperm injection (ICSI) was referred to our group for assessment. Upon clinical examination, a ptosis (partial closure of the eyelid) was noted, and histology revealed ragged red fibres in the skeletal muscle. Southern blot analysis of spermatozoa and skeletal muscle revealed the presence of multiple mitochondrial DNA deletions. This kind of rearrangement may be of nuclear origin since three nuclear loci have been ascribed to multiple mitochondrial DNA deletions in humans. Since mitochondrial DNA is maternally transmitted, the use of ICSI was feasible. However, an alteration of nuclear gene product affecting the integrity of mitochondrial DNA, and thus sperm mobility, might be transmitted to the offspring with the risk of developing a mitochondrial DNA disease.   相似文献   
996.
Peripheral blood T cell subsets were evaluated in 11 patients during the reconstitution phase after allogeneic bone marrow transplantation and compared with 11 age-matched controls. The proportion of cells coexpressing Leu7 and CD11b (C3bi receptor) markers was determined within the CD4+ (T-helper) and the CD8+ (T-suppressor) subsets by two- color immunofluorescence analysis. CD4+ and CD8+ T cells reached normal or near-normal values within the first year posttransplant. In contrast to normal controls, however, most of the cells in both subsets coexpressed the Leu7 and CD11b markers. T cells with such phenotype display the morphological features of granular lymphocytes (GLs) and a functional inability to produce interleukin 2 (IL 2). These T cell imbalances were not related to graft v host disease (GvHD) or to clinically detectable virus infections and may account for some defects of cellular and humoral immunity that occur after bone marrow transplantation.  相似文献   
997.
This study combines the pharmacologically-induced penile erection (PIPE) technique with radionuclide phallography (RNP) for the non-invasive study of penile haemodynamic changes during erection. Penile erections produced by the intracavernosal injections of two different vasoactive drugs, prostaglandin E1 (PGE1) and papaverine HCl (PPV) were assessed by quantitation of the dynamic RNP and parameters of erection were defined and compared. PGE1 intracavernosal injections were seen to elicit a better erectile response than PPV. Dynamic radionuclide phallography was performed using 99Tcm-labelled autologous RBCs in five normally potent volunteers, sixteen patients with psychogenic impotence, seven patients with vasculogenic impotence (three arteriogenic, four venous leakage) and one patient with neurogenic impotence. Physical parameters of erection including the penile length and circumference changes during erection and the erectile angle were compared with the indices of penile blood flow and volume derived through quantitation of the RNP. There was a close correlation between the penogram index (an index of penile blood volume) and penile circumference increase during erection (r = 0.77, p less than 10(-6). The erectile angle, a measure of penile rigidity, correlated strongly (r = 0.82, p less than 10(-6) with the flow index, a measure of penile blood volume. Patterns specific to various categories of impotence were observed and these aided in the diagnosis, especially in equivocal cases with a suboptimal clinical response to the intracavernosal injection. Quantitative RNP offers a non-invasive method which allows direct objective assessment of the erectile response providing several quantitative parameters for analysis.  相似文献   
998.
999.
A sudden surge in the release of glutamate is currently believed to be an important initiating step in neuronal damage due to an ischemic insult. In this experiment, we tested the efficacy of neuroprotection with lamotrigine, a novel antiepileptic drug that blocks voltage gated sodium channels and inhibits the ischemia-induced release of glutamate in the gerbil forebrain model of cerebral ischemia. The medication was administered 30 min before and 30 min after the insult in two groups of animals. Histological assessment of neuronal damage was evaluated at 7 and 28 days after the ischemic insult. Animals evaluated at 28 days also underwent behavioral testing. Microdialysis was used in the same model to study the response of ischemia-induced glutamate in saline treated controls versus animals treated with lamotrigine 20 min before the insult. There was highly significant neuronal protection in animals who were treated with lamotrigine either before or after the insult. Protection was seen both at 7 and 28 days after the insult. Behavioral testing also showed significantly better recovery in both sets of animals in comparison to the saline-treated group. Microdialysis confirmed a significant attenuation of the ischemia-induced glutamate surge when compared to the saline-treated animals. Our morphological, behavioral and microdialysis experiments show that lamotrigine offers significant neuroprotection from the effects of transient forebrain ischemia in gerbils. Neuroprotection with post-ischemic therapy probably depends on preserving the capacity of the sodium/calcium exchanger to reduce intracellular calcium concentrations or persistent `toxicity' of glutamate in the reperfusion period on the already `primed' injured neurons. These concepts need further study.  相似文献   
1000.
A 75-year-old woman had breast carcinoma, an IgA paraprotein and autopsy-proven amyotrophic lateral sclerosis. Autopsy tissues showed immune-reactive IgA within surviving motor neurons and deposits of IgA and C3 within renal glomeruli. By indirect immunofluorescence, the patient's serum contained high-titer IgA that bound to axons and to the perikarya of nerve cells in central and peripheral nervous system. The IgA paraprotein reacted with the 200 kDa, high molecular weight subunit of neurofilament protein (NFH) in Western blots of purified neurofilaments. It also reacted with dephosphorylated NFH and with NFH expressed as a fusion protein in E. coli, suggesting that the autoantibody recognized a peptide epitope. The IgA crossreacted with a surface antigen of cultured human neuroblastoma cells but mouse monoclonal antibodies to NFH did not. Absorption of the patient's serum with neurofilaments eliminated IgA binding to neuroblastoma cells, indicating that the same antibodies bound to both determinants. The IgA paraprotein seems to be an autoantibody with specificity for neurofilament protein and a cell surface component of neuronal cells; the antibody may have been important in the pathogenesis of neuronal degeneration.  相似文献   
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