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Five infants with biopsy proved juvenile xanthogranuloma of the iris were reviewed. Early treatment with subconjunctival injection of steroids and topical steroid drops resulted in regression of the lesion in four patients. One patient, reviewed at the age of 8 months after glaucoma which had developed secondary to the iris xanthogranuloma, had been treated by surgery alone: the visual outcome was very poor. 相似文献
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Acquired Brown''s syndrome in a patient with combined lichen sclerosus et atrophicus and morphoea. 总被引:2,自引:2,他引:0 下载免费PDF全文
A 49-year-old woman with generalised lichen sclerosus et atrophicus and morphoea developed bilateral Brown's syndrome. Some of the skin lesions were in the vicinity of the trochlea. A characteristic feature of morphoea is subcutaneous fibrosis, so we postulate that the cause of the Brown's syndrome was mechanical tethering of the superior oblique tendon by deep subdermal fibrosis. Histopathological diagnosis was made from biopsies of similar lesions on the patient's face. 相似文献
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ABSTRACT: A Male rabbit was immunized with rat testicular cytochrome (Cyt) ct and mated with normal, unimmunized females. The matings resulted in abnormal pregnancies: no offspring or stillborn or undersized liveborn offspring weighing 25–30 gm each. Another unusual observation was that fur-pulling behavior, normally exhibited by pregnant female rabbits at the end of the gestational period, was absent in all of these pregnancies. Therefore, immunization of a normal rabbit with testicular cyt ct appeared to interfere with physiological and behavioral aspects of pregnancy in normal female rabbits. The immunological basis of these findings remains to be determined. 相似文献
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We have developed a highly sensitive cytolysis test, the fluorolysis assay, as a simple nonradioactive and inexpensive alternative to the standard 51Cr-release assay. P815 cells were stably transfected with a plasmid expressing the enhanced green fluorescent protein (EGFP) gene. These target cells were coated with or without cognate peptide or anti-CD3 Ab and then incubated with CD8(+) T cells to allow antigen-specific or nonspecific lysis. The degree of target cell lysis was measured using flow cytometry to count the percentage of viable propidium iodide(-) EGFP(+) cells, whose numbers were standardized to a reference number of fluorochrome-linked beads. By using small numbers of target cells (200-800 per reaction) and extended incubation times (up to 2 days), the antigen-specific cytolytic activity of one to two activated CD8(+) T cells of a CTL line could be detected. The redirected fluorolysis assay also measured the activity of very few (> or =6) primary CD8(+) T cells following polyclonal activation. Importantly, antigen-specific lysis by small numbers (> or =25) of primary CD8(+) T cells could be directly measured ex vivo. This exquisite sensitivity of the fluorolysis assay, which was at least 8-33-folds higher than an optimized 51Cr-release assay, allows in vitro and ex vivo studies of immune responses that would otherwise not be possible due to low CTL numbers or frequencies. 相似文献
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Lung inflation and alveolar permeability to non-electrolytes in the adult sheep in vivo. 总被引:1,自引:0,他引:1 下载免费PDF全文
1. Experiments were performed on adult sheep to determine the effect of lung distension on the passive permeability of alveoli to water soluble non-electrolytes. With the animal breathing oxygen spontaneously, a segment of one lung was isolated by passing a balloon-tipped catheter through a tracheostomy into a distal bronchus. This isolated atelectatic segment was filled with an isosomotic saline solution containing radio-labelled solutes of known molecular size: [125I]albumin, [14C]inulin, [14C]-sucrose, [3H]mannitol, and [14C]urea. The segment was inflated with oxygen either to a preselected pressure, or to a predetermined fraction of its capacity. Inflation was then maintained for several 10-15 min periods between which the oxygen supply was disconnected and the saline sampled, allowing the tracer concentrations to be measured. 2. At low inflating pressures (20-32 cmH2O) and at low volumes (24-54% of capacity), alveolar permeability to water soluble solutes was slight and could be characterized in terms of a membrane penetrated by cylindrical water filled pores of 0-5-1-6 nm radius. In all experiments showing restricted diffusion, absorption of saline occurred. 3. There was a positive correlation between the degree of lung inflation and pore radius in both the pressure controlled and volume controlled experiments. At high inflating pressures and at inflation volumes which were close to the total capacity of the isolated segment, restriction of solute diffusion was lost; in five out of six such experiments there was a net movement of liquid into the alveoli. 4. These results can be explained by postulating that as the lung epithelium is progressively stretched there is an opening up of water filled channels between alveolar cells. At peak inflation, restriction of diffusion of water soluble solutes is lost, and the alveolar epithelium ceases to function as a barrier between the circulation and air spaces. 相似文献
7.
Changes in non-electrolyte permeability of alveoli and the absorption of lung liquid at the start of breathing in the lamb. 总被引:2,自引:0,他引:2 下载免费PDF全文
1. Experiments were done on mature foetal lambs, 135-145 days in gestation, exteriorized at Caesarean section, and on new-born lambs aged 12-60 hr. In the foetal lambs, test substances were added to lung liquid and then spontaneous ventilation was induced or the lungs were statically inflated with gas or saline. In the new-born lambs, the left lung was ventilated in order to maintain respiratory gas-exchange, while foetal lung liquid, taken from previous experiments and containing test substances, was introduced into the right lung, which was then inflated with gas and used for permeability measurements. In both foetuses and new-borns, the gas used was O2 or N2O and, at 20 min intervals, ventilation or static inflation was interrupted, the gas in the lungs absorbed into the circulation and the remaining liquid sampled through the trachea. The following test substances were used in various combinations: [14C]-erythritol, [3H]sucrose, [14C]inulin, [131I]albumin, and the polymer [131I]-PVP. The last of these was separated, after the experiments, by gel filtration with Sephadex G200 or G50, into fractions of defined molecular radius. [131I]albumin, or a large molecule fraction of [131I]PVP, was used as a volume marker. 2. Spontaneous ventilation was associated with the absorption of liquid and with an alteration in the foetal pattern of non-electrolyte permeability that could be characterized by postulating an opening up of water-filled cylindrical pores to 34-56 A in radium. In the new-born lambs, the results suggested pores 7-14 A in radius. 3. Static inflation of the foetal lungs with gas, to pressures of 25-35 cmH2O, gave permeabilities appropriate for pores 5-5-12 A in radius. Static inflation with gas, to pressures of 41-49 cmH2O, produced changes appropriate for much larger channels, more than 125 A in radius and possibly much larger. With one exception, expansion with saline produced changes similar to those obtained by gas inflation to 25-35 cmH20. 4. It was concluded that in the initial stages of pulmonary ventilation a change takes place in alveolar epithelial cells. The increase in size would be sufficient to allow for rapid liquid absorption, but is not so great as to permit significant penetration by plasma albumin. The results obtained in the lung of the new-born lamb statically inflated to 25-32 cmH2O suggest that, following the initial adaptation, alveolar permeability returns towards the foetal pattern, although the pores remain larger than in the foetus. The change in permeability pattern at birth appears to depend on the degree of lung expansion with gas. 相似文献
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H. REIJONEN S. NEJENTSEV J. TUOKKO S. KOSKINEN E. TUOMILEHTO-WOLF H. K. KERBLOM J. ILONEN THE CHILDHOOD DIABETES IN FINLAND STUDY GROUP 《International journal of immunogenetics》1997,24(5):357-363
We determined the distribution of DR4 subtypes in 309 DQB1*0302-positive haplotypes found in insulin-dependent diabetes mellitus (IDDM) patients and 70 control haplotypes present only in healthy family members. An increased frequency of DRB1*0401 allele (74.4% vs. 55.7%, P = 0.003) and a decrease of DRB1*0404 allele (23.6% vs. 40.0%, P = 0.0064) was revealed. A further analysis of extended haplotypes demonstrated strong linkages between various B alleles and DRB1*04 subtypes. HLA-B39 was more frequent in DRB1*0404–DQB1*0302-positive IDDM haplotypes compared with control ones (37.0% vs. 14.3%, P = 0.049), suggesting an involvement of the region telomeric to HLA-DRB1 in the susceptibility to IDDM. 相似文献
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