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1.
The effect of imipramine, desipramine, ketanserin and lithium on Type II glucocorticoid receptor (GR) mRNA levels was studied in rat brain regions involved in the control of the hypothalamo-pituitary-adrenal (HPA) axis, the dysregulation of which has been implicated in the pathophysiology of major depression. Northern blot analysis of Type II GR mRNA showed that treatment of male rats with either desipramine or imipramine increased hypothalamic and hippocampal GR mRNA levels. Upregulation of GR mRNA following administration of imipramine was found in brain regions of female rats, while desipramine had no effect. Ketanserin increased levels of GR mRNA in hippocampus of male, but not female, rats. Lithium also was able to induce important increases rat brain GR mRNA; this effect was particularly marked in females.
We conclude that desipramine, imipramine, ketanserin and lithium can modulate GR mRNA in regions of rat brain involved in the control of the HPA axis and may have a common mechanism of action at the level of the GR gene. Sexual dimorphism for drug regulation of brain GR mRNA content was shown and may be related to sex differences in the prevalence of certain affective disorders. 相似文献
2.
In order to compare a group of patients with a polymyositis (PM) to a control group, 28 cases of primary myopathies were examined by morphometry with regard to differences between central and peripheral muscle fibers in muscle fascicles. A significant difference in favor of peripheral muscle fibers, i.e., a peripheral hypertrophy was found in 22 out 28 cases (significantly in 14 cases). Therefore, histometry is a valuable additional method for discrimination between PM and primary myopathies. 相似文献
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4.
The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or primary percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.
Pathophysiology
Changes in the definition of terms relating to the diagnosisof myocardial infarction (MI) have evolved by better understandingof the pathophysiology culminating in the new term of acutecoronary syndrome (ACS). Figure 1 illustrates the processesthat occur in the development of an acute coronary event. 相似文献
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6.
Adult-onset rod disease with abundant intranuclear rods 总被引:2,自引:0,他引:2
Summary The third case of adult-onset rod disease (nemaline myopathy) with abundant myofibrillar as well as intranuclear rods is described. The 61-year-old woman suffered from progressive weakness of proximal extremities and of the neck, mimicking polymyositis. Muscle biopsy revealed a striking myopathic pattern, with intranuclear rods occurring in 31% of the fibres. On light and electron microscopy and by immunohistochemical study, the rods differed from myofibrillar rods. The absence of -actinin in intranuclear rods suggests an enhanced readiness of actin filaments to bind to diverse proteins, instead of overproduction of -actinin as the pathogenetic basis of the rod formation. 相似文献
7.
Piracy of Decay-Accelerating Factor (CD55) Signal Transduction by the Diffusely Adhering Strain Escherichia coli C1845 Promotes Cytoskeletal F-Actin Rearrangements in Cultured Human Intestinal INT407 Cells 总被引:2,自引:0,他引:2 下载免费PDF全文
Isabelle Peiffer Alain L. Servin Marie-Franoise Bernet-Camard 《Infection and immunity》1998,66(9):4036-4042
Diffusely adhering Escherichia coli (DAEC) C1845 (clinical isolate) harboring the fimbrial adhesin F1845 can infect cultured human differentiated intestinal epithelial cells; this process is followed by the disassembly of the actin network in the apical domain. The aim of this study was to examine the mechanism by which DAEC C1845 promotes F-actin rearrangements. For this purpose, we used a human embryonic intestinal cell line (INT407) expressing the membrane-associated glycosylphosphatidylinositol (GPI) protein-anchored decay-accelerating factor (DAF), the receptor of the F1845 adhesin. We show here that infection of INT407 cells by DAEC C1845 can provoke dramatic F-actin rearrangements without cell entry. Clustering of phosphotyrosines was observed, revealing that the DAEC C1845-DAF interaction involves the recruitment of signal transduction molecules. A pharmacological approach with a subset of inhibitors of signal transduction molecules was used to identify the cascade of signal transduction molecules that are coupled to the DAF, that are activated upon infection, and that promote the F-actin rearrangements. DAEC C1845-induced F-actin rearrangements can be blocked dose dependently by protein tyrosine kinase, phospholipase Cγ, phosphatidylinositol 3-kinase, protein kinase C, and Ca2+ inhibitors. F-actin rearrangements and blocking by inhibitors were observed after infection of the cells with two E. coli recombinants carrying the plasmids containing the fimbrial adhesin F1845 or the fimbrial hemagglutinin Dr, belonging to the same family of adhesins. These findings show that the DAEC Dr family of pathogens promotes alterations in the intestinal cell cytoskeleton by piracy of the DAF-GPI signal cascade without bacterial cell entry. 相似文献
8.
Yongchol Shin Atsushi Kitayama Tetsuya Koide Daniel A Peiffer Makoto Mochii Arnold Liao Naoto Ueno Ken W Y Cho 《Developmental dynamics》2005,232(2):432-444
To isolate novel genes regulating neural induction, we used a DNA microarray approach. As neural induction is thought to occur by means of the inhibition of bone morphogenetic protein (BMP) signaling, BMP signaling was inhibited in ectodermal cells by overexpression of a dominant-negative receptor. RNAs were isolated from control animal cap explants and from dominant-negative BMP receptor expressing animal caps and subjected to a microarray experiment using newly generated high-density Xenopus DNA microarray chips representing over 17,000 unigenes. We have identified 77 genes that are induced in animal caps after inhibition of BMP signaling, and all of these genes were subjected to whole-mount in situ hybridization analysis. Thirty-two genes showed specific expression in neural tissues. Of the 32, 14 genes have never been linked to neural induction. Two genes that are highly induced by BMP inhibition are inhibitors of Wnt signaling, suggesting that a key step in neural induction is to produce Wnt antagonists to promote anterior neural plate development. Our current analysis also proves that a microarray approach is useful in identifying novel candidate factors involved in neural induction and patterning. 相似文献
9.
We report results obtained using the monoclonal antibody M-II 68, which recognizes inner mitochondrial membrane in routinely processed (formalin-fixed and paraffin-embedded) tissue by light microscopic immunohistochemistry. In ten normal brains, the range of immunoreactivity in various cell types and locations was defined. The most intense staining was observed in Purkinje cells, in neurons of cranial nerve nuclei, pons and substantia nigra, as well as in choroid plexus epithelial cells. By comparison with this control group, one case of primary mitochondrial encephalomyopathy exhibited increased staining of endothelial and vascular smooth muscle cells, choroid plexus epithelial cells, and neurons of various locations. Scattered ragged-red fibres were heavily labelled in one case of mitochondrial myopathy, while ten muscles without mitochondriopathy were left unstained. Our method is able to detect accumulations of mitochondria and increases in mitochondrial cristae density. It could prove useful for differential diagnosis of routine biopsy material and for clarification of cell types involved in mitochondrial cytopathies. 相似文献
10.
Yanfang Li Menda LP Qiuliang WU Fuyuan Liu Jundong Li Jinglin Zou Yongwen Huang 《中国肿瘤临床(英文版)》2004,1(3):180-184
Objective Ovarian dysgerminoma is an uncommon ovarian malignancy, Its clinicai features are special and there are many factors affecting
its prognosis. If treated properly, the patient can be cured. Otherwise it may endanger the patient’s life. The aim of this
study is to investigate the clinical features and factors related to prognosis of ovarian dysgerminoma.
Methods Data from 57 patients with pure ovarian dysgerminoma were analyzed retrospectively. The patients were admitted to the Cancer
Center, Sun Yat-sen University from January 1.1964 to December 31, 2000.
Results The main clinical features were abdominal mass (56.1% ), abdominal pain (21.1% ), abdominal swelling (17.5%.), vaginal bleeding
(5.3% )and genital tract abnormalities (5.3%). Twenty-six patients had stage I diseases, 8 stage II.9 stage III.1 stage IV
and 13 recurrent and persistent diseases. The uterus was involved in 41.2% of patients with stage II -III diseases. Combined
modality was given to 52 cases and a single-method treatment to 5 cases. The total overall 5 and 10-year survival rates for
stages I-IV was 80.1 % and 70.0% respectively. The 5-year survival rate for stage I was 100%, stage II 55.2%. stage III 55.6%
and stage IV 0%; for recurrent and persistent diseases, 72.7%. The stage I group of 12 patients. received adnexectomy and
14 patients underwent hysterectomy and adnexa removal. There was no significant difference between the 5 and 10-year survival
rates (all 100%). Of the 23 patients in the stage I group to whom oniy chemotherapy was given after operation, 19 cases received
3 or more courses and were well without recurrence; 4 patients received only one course and one of them recurred 21 months
after the operation. In the group of stages II and III cases, the 5-year survival rate was 86.7% for those whose chemotherapy
courses were 3≥ 4 and 25.0% for patients who received less than 4 courses of chemotherapy (P<0.05).
Conclusions The prognosis of ovarian dysgerminoma is closely related to the disease stage and treatment modality. A fertility-preserving
operation can be considered in early -staged patients, but caution needs to be exercised in the middle to late staged cases.
Good results can be achieved with an operation-based combined modality in recurrent patients. 相似文献