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31.
In order to determine the principal histologic features in distinguishing the "anaplastic" from the "well differentiated" oligodendroglioma and mixed glioma (oligo-astrocytoma), correlations between the growth fraction, and histologic grade and 6 histologic variables (vascular proliferation, cytologic pleomorphism, calcification, necrosis, cellularity, mitotic index) were studied in 24 patients. The growth fraction was calculated as the percentage of Ki-67-immunostained nuclei in frozen sections using Ki-67 monoclonal antibody. 6 histologic variables were checked with HE stain of paraffin-embedded tissue sections. The growth fraction was in general agreement with the histologic grade, in order of decreasing mean percentage, ranging from 11.1% (anaplastic mixed glioma) to 5.3% (anaplastic oligodendroglioma), 2.8% (isomorphic oligo.) and 1.9% (mixed, grade II). There was a significant association between the growth fraction and 3 histologic variables (vascular proliferation, cytologic pleomorphism, mitotic index) out of 6. Thus, even though there exist some gaps between these parameters in paraffin-embedded tissues and those in frozen sections, the percentage of Ki-67-immunostained nuclei is likely to be very valuable as a supplement information of histological grading and a prognostic indicator.  相似文献   
32.
To provide baseline information for the "local" therapy of the glioblastoma multiforme (GBM), whole-brain histological sections of 15 untreated GBM's were studied to determine the distribution of neoplastic cells. These findings were then compared with the computerized tomography (CT) scans in 11 cases in order to determine the extent to which the peripheral portion of the neoplasm can be estimated by the presence of a low-density area without contrast enhancement. The results of the histological study confirmed the marked heterogeneity of GBM's and disclosed a great variability in the geometry, extent, and character of the peripheral "infiltrating" margin. In spite of the widely held concept that glioblastomas are localized within 2 cm of the contrast-enhanced rim, there were three cases in this two-dimensional study in which this distance was exceeded, and it seems likely that three-dimensional reconstructions would have detected additional cases in which neoplastic cells extended beyond this arbitrary limit. Only three of the 15 GBM's were restricted to the distribution of one internal carotid or one vertebral artery. To the extent that the neoplasms in the present series are representative, this suggests that glioblastomas will be difficult to treat successfully by intra-arterial therapy using existing therapeutic agents. Correlations of histological sections with the CT scans revealed that the vast majority of the neoplastic tissue was contained within the contrast-enhancing and "peritumoral" areas of low density, but that in five cases fingers of neoplasm extended for short distances beyond the outer margin of the latter region. This indicates that the distribution of cells of a GBM cannot be inferred from CT images since the "peritumoral" area of low density can over- or underestimate the extent of the lesion.  相似文献   
33.
Summary Changes in capillary walls between human glial, non-glial and metastatic brain tumors were studied with conventional ultrathin section and freeze-fracture replica techniques. The following results were obtained. (1) In glial tumors, ultrathin section studies showed cell junctions of the capillaries were either short or elongate. Moreover, endothelial hyperplasia, surface infolding of endothelial cells, irregularity of the basal lamina and a large extravascular space were observed. Freeze-fracture replicas of capillary endothelium showed tight junctions as two to seven strands. In addition, pinocytotic vesicles had increased markedly and were an average of 25 per m2. Both ultrathin and freeze fracture studies showed that, in contrast to malignant gliomas, there were only slight changes in benign astrocytomas. (2) In non-glial tumors, ultrathin sections showed surface infoldings, increased vesicles, many fenestrations of endothelial cells, irregularity of basal lamina and enlarged perivascular space. Freeze-fracture replicas of vascular endothelium, showed that the average number of pinocytotic vesicles and fenestrations were 25 and 22 per m2, respectively. Moreover, the tight junction was composed of one or two strands which appeared to be a discontinuous array of particles. (3) In metastatic brain tumors, ultrathin studies showed capillary endothelia were proliferated, had marked infolding, and showed an increased number of pinocytotic vesicles and many fenestrations. Moreover, short and elongate intercellular junctions were presented but no open junction was detected. Finally the basal lamina lost its three-layered appearance and was irregular in width. Freeze-fracture replicas showed pinocytotic vesicles had increased and were 24 per m2 on average in four cases, but fenestrations and tight junctions could not be detected. The most fundamental feature of vessels in these three different kinds of tumors was whether they were fenestrated or not. Glial tumors were non-fenestrated, whereas non-glial and metastatic tumors were fenestrated.  相似文献   
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The aim of this study was to determine the in-phantom thermal neutron distribution derived from neutron beams for intraoperative boron neutron capture therapy (IOBNCT). Gold activation wires arranged in a cylindrical water phantom with (void-in-phantom) or without (standard phantom) a cylinder styrene form placed inside were irradiated by using the epithermal beam (ENB) and the mixed thermal-epithermal beam (TNB-1) at the Japan Research Reactor No 4. With ENB, we observed a flattened distribution of thermal neutron flux and a significantly enhanced thermal flux delivery at a depth compared with the results of using TNB-1. The thermal neutron distribution derived from both the ENB and TNB-1 was significantly improved in the void-in-phantom, and a double high dose area was formed lateral to the void. The flattened distribution in the circumference of the void was observed with the combination of ENB and the void-in-phantom. The measurement data suggest that the ENB may provide a clinical advantage in the form of an enhanced and flattened dose delivery to the marginal tissue of a post-operative cavity in which a residual and/or microscopically infiltrating tumour often occurs. The combination of the epithermal neutron beam and IOBNCT will improve the clinical results of BNCT for brain tumours.  相似文献   
37.
Relationship between SIRS and CARS in the pathologic condition of acute pancreatitis was discussed. SIRS promotes excessive inflammatory reaction and CARS induces the susceptibility to infection. Both conditions can develop into organ failure in acute pancreatitis. Hence, countermeasures for both conditions are mandatory in the care of patients with acute pancreatitis.  相似文献   
38.
Somatic mitochondrial mutation in gastric cancer.   总被引:11,自引:1,他引:11       下载免费PDF全文
Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression.  相似文献   
39.
The effects of electrical stimulation of ventral subiculum (VSB) of the hippocampus of the thermosensitive neurons in the preoptic area were studied in urethane-anesthetized rats. VSB stimulation affected thermosensitive neurons more frequently (92.1%, 58 of 63) than thermally insensitive neurons (71.4%, 55 of 77). The majority of the VSB-responsive thermosensitive neurons (33 of 44 warm-units and 11 of 14 cold-units) were initially inhibited following stimulation. The result provides further support for the involvement of hippocampus in the central control of thermoregulation.  相似文献   
40.
New Zealand Black (NZB) mice spontaneously develop a severe autoimmune hemolytic anemia due to the production of anti-mouse red blood cell (MRBC) autoantibodies. The contribution of variable region genes and somatic mutations in the pathogenicity of anti-MRBC autoantibodies was investigated by mRNA sequencing of eight NZB anti-MRBC monoclonal autoantibodies, among which five are capable of inducing anemia in BALB/c mice. Here we report that at least three VH gene families (J558, J606 and 3609) and five Vchi subgroups (V chi 8, 9, 19, 21 and 28), in combination with several D, JH and Jchi gene segments, encode anti-MRBC autoantibodies. Thus, the NZB anti-MRBC autoantibodies, whether pathogenic or not, are encoded by a large number of immunoglobulin gene elements and by members of known VH and Vchi gene families with preferential usage of VH gene families most distal to the D regions. The presence of several mutations in the JH gene segments of both IgM and IgG anti-MRBC autoantibodies, whether pathogenic or not, strongly suggests that their VH regions may be highly mutated and that the mechanism of somatic diversification might be important in the generation of anti-MRBC autoantibodies. Our results support the idea that anti-MRBC autoimmune responses are likely to be generated by an antigen-driven mechanism.  相似文献   
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