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排序方式: 共有646条查询结果,搜索用时 16 毫秒
81.
In a case-finding study in a municipality in central Sweden, 128 cases of chronic open-angle glaucoma with visual field defects (VFD) were found. The prevalence amounted to 1.4% in those greater than or equal to 45 years of age. Sixty-three percent had capsular glaucoma. Advanced visual field defects (AVFD), i.e. a restriction of the visual field to a diameter of less than or equal to 20 degrees, were seen in 49 patients. Four patients had AVFD in both eyes. Patients with AVFD were older, had had the disease longer, had higher mean initial intraocular pressure (IOP), and had more extensive VFD at the time of diagnosis. When age and duration were taken into consideration, the risk of developing AVFD was 14 times greater in those with VFD stage III at the time of diagnosis, i.e. a Bjerrum scotoma with nasal breakthrough or more widespread VFD. An IOP of greater than or equal to 35 mmHg signified that the risk of having VFD stage III at the time of diagnosis, when age and type of glaucoma were taken into consideration, was 8.6 times greater than if the IOP was less than 35 mmHg. 相似文献
82.
83.
The preganglionic nerves of the rat urinary bladder were cut. The decentralized bladders gained markedly in weight. Both one and four weeks post-operatively, transmural nerve stimulation evoked contractile responses of the muscle strips of the decentralized bladders, that were of the same magnitude as those of the control bladders. However, four weeks post-operatively, the atropine resistant fraction of the response was decreased; consequently, the atropine sensitive (cholinergic) fraction was increased. The activity of the acetylcholine synthesizing enzyme, choline acetyltransferase, was increased at the late time of observation. The present biochemical and functional findings may suggest outgrowth of branches from the decentralized post-ganglionic cholinergic nerves. 相似文献
84.
Karin Ekstr?m Smedby Eva Baecklund Johan Askling 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2069-2077
Certain autoimmune and chronic inflammatory conditions, such as Sj?gren's syndrome and rheumatoid arthritis (RA), have consistently been associated with an increased risk of malignant lymphomas, but it is unclear whether elevated lymphoma risk is a phenomenon that accompanies inflammatory conditions in general. Likewise, it is debated whether the increased risk identified in association with some disorders pertains equally to all individuals or whether it varies among groups of patients with different phenotypic or treatment-related characteristics. It is similarly unclear to what extent the increased lymphoma occurrence is mediated through specific lymphoma subtypes. This update reviews the many findings on risks, risk levels, and lymphoma characteristics that have been presented recently in relation to a broad range of chronic inflammatory, including autoimmune, conditions. Recent results clearly indicate an association between severity of chronic inflammation and lymphoma risk in RA and Sj?gren's syndrome. Thus, the average risk of lymphoma in RA may be composed of a markedly increased risk in those with most severe disease and little or no increase in those with mild or moderate disease. The roles of immunosuppressive therapy and EBV infection seem to be limited. Furthermore, RA, Sj?gren's syndrome, systemic lupus erythematosus, and possibly celiac disease may share an association with risk of diffuse large B-cell lymphoma, in addition to well-established links of Sj?gren's syndrome with risk of mucosa-associated lymphoid tissue lymphoma and of celiac disease with risk of small intestinal lymphoma. However, there is also obvious heterogeneity in risk and risk mediators among different inflammatory diseases. 相似文献
85.
Incidence and prevalence of juvenile chronic arthritis: a population survey. 总被引:1,自引:1,他引:0 下载免费PDF全文
B Andersson G?re A Fasth J Andersson G Berglund H Ekstr?m M Eriksson L Hammarén L Holmquist E Ronge A Thilen 《Annals of the rheumatic diseases》1987,46(4):277-281
In a population based epidemiological survey of juvenile chronic arthritis (JCA), performed in Western Sweden in 1983, an incidence of 12/100,000 was found. The estimated prevalence was 56/100,000. Subgroup distribution showed a preponderance of mono- and pauciarticular forms. The peak age of onset was between 0 and 4 years of age. Girls predominated over boys in a ratio of 3:2. Overall, 30% were antinuclear antibody (ANA) positive, 9% rheumatoid factor (RF) positive, and eye involvement occurred in 10% of the children. The results suggest differences in population based studies of JCA compared with previously reported hospital based series. 相似文献
86.
Ontogenetic development of serotoninergic neurons in the brain of a teleost, the three-spined stickleback. An immunohistochemical analysis 总被引:2,自引:0,他引:2
The ontogenetic development of serotoninergic neurons in the brain of the stickleback was investigated with the indirect immunocytochemical peroxidase-antiperoxidase technique, using a specific antibody to serotonin (5-hydroxytryptamine, 5-HT). Formation of neuronal populations takes place during embryonic development. By 80 h after fertilization, the first 5-HT perikarya have appeared in the ventricular zone of the hypothalamus (nucleus recessus lateralis) and the raphe region. At 108 h the first 5-HT perikarya can be observed in area praetectalis. At 118 h a transient group of 5-HT neurons appears rostral to the nucleus recessus lateralis, and at this same age the first 5-HT perikarya may be visualized in nucleus recessus posterioris. A group of 5-HT neurons appears in the dorsolateral tegmentum at 166 h (one day after hatching, which occurs at 120-144 h after fertilization). Differentiation of the neuronal populations, in terms of migration and formation of subdivisions, starts between 80 h and 94 h, and seems to be completed between 1 and 5 days after hatching. Raphe nuclei form an anterior group comprising nuclei raphe dorsalis, raphe medialis and a ventrolateral group, and a posterior group comprising a nucleus raphe pallidus/obscurus complex, a lateral nucleus reticularis paragigantocellularis and a ventromedial nucleus raphe magnus. The posterior and ventral raphe nuclei, which are well developed at the time of hatching, have not been visualized in the adult stickleback. While formation of 5-HT neuronal systems, as well as their primary efferent pathways, takes place during early ontogenetic development, the establishment of terminal areas and their subsequent differentiation apparently takes place during later ontogenetic stages. Most presumptive target areas are penetrated by 5-HT axons at hatching, although terminal formation does not seem to start until later. A considerable number of 5-HT neuronal groups present in the embryonic and newly hatched stickleback have not been visualized in the adult stickleback. This may be due to selective cell death, changes in transmitter phenotype or maturation of axonal transport processes during development. 相似文献
87.
88.
Preponderance for either alpha- or beta-adrenoceptor mediated sensitization in the rat submaxillary gland 总被引:1,自引:0,他引:1
The sensitivity of the rat submaxillary gland was examined 3-4 weeks after either parasympathetic decentralization or sympathetic decentralization or denervation. The threshold doses for secretion of saliva of parasympathomimetic (methacholine) and sympathomimetic (noradrenaline, adrenaline, phenylephrine and isoprenaline) drugs were estimated and the amount of saliva secreted in response to supraliminal doses of these drugs was measured. Each type of operation caused the development of a supersensitivity that involved all three types of receptors, i.e. muscarinic cholinoceptors, alpha-adrenoceptors and beta-adrenoceptors. Following parasympathetic decentralization the sensitization was predominantly mediated via alpha-adrenoceptors, and also via cholinoceptors. Following sympathetic decentralization or denervation the postjunctional sensitization was predominantly mediated via beta-adrenoceptors; most of the supersensitivity to noradrenaline, adrenaline and phenylephrine found after sympathetic denervation was of the prejunctional type. An increase in receptor density and an intracellular arrangement where the response of cholinoceptors and alpha-adrenoceptors is mediated via one pathway and the response of beta-adrenoceptors via another are suggested as factors that may be of importance for the development of the postjunctional supersensitivity. The present study shows that the traffic of secretory impulses in the sympathetic nerve is of importance for the level of sensitivity of the secretory cells. Since postjunctional supersensitivity following sympathetic denervation did not exceed that following sympathetic decentralization it is suggested that under normal conditions a continuous release of noradrenaline from the nerve endings is of little importance for the level of sensitivity. 相似文献
89.
J Ekstr?m 《Acta pharmacologica et toxicologica》1979,44(5):377-384
6-hydroxydopamine (100 mg/kg injected intravenously twice with a weekly interval) was used for the destruction of the adrenergic nerves in the rat detrusor muscle. Two to three weeks after the first injection of this substance the sensitivity of the detrusor muscle to parasympathomimetic and sympathomimetic drugs was tested by recording the intravesical pressure in situ. The sensitivity to methacholine was found to be unchanged, whereas a supersensitivity to noradrenaline, adrenaline, phenylephrine and isoprenaline was found to have developed, thus involving both alpha-adrenoceptor mediated contraction and beta-adrenoceptor mediated relaxation. The supersensitivity was of the postjunctional type. 相似文献
90.
Vahter ME Li L Nermell B Rahman A El Arifeen S Rahman M Persson LA Ekström EC 《Journal of health, population, and nutrition》2006,24(2):236-245
This study assessed the exposure of pregnant women to arsenic in Matlab, Bangladesh, an area with highly-elevated concentrations of arsenic in tubewells, by measuring concentrations of arsenic in urine. In a defined administrative area, all new pregnancies were identified by urine test in gestational week 6-8, and women were asked to participate in the assessment of arsenic exposure. Urine for analysis of arsenic was collected immediately and in gestational week 30. In total, 3,426 pregnant women provided urine samples during January 2002-March 2003. There was a considerable variation in urinary concentrations of arsenic (total range 1-1,470 microg/L, adjusted to specific gravity 1.012 g/mL), with an overall median concentration of 80 microg/L (25th and 75th percentiles were 37 and 208 microg/L respectively). Similar concentrations were found in gestational week 30, indicating no trend of decreasing exposure, despite the initiation of mitigation activities in the area. Arsenic exposure was negatively associated with socioeconomic classes and achieved educational level. There were marked geographical variations in exposure. The results emphasize the urgent need for efficient mitigation activities and investigations of arsenic-related reproductive effects. 相似文献