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排序方式: 共有396条查询结果,搜索用时 15 毫秒
1.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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Plasma alpha beta levels have been examined in sporadic Alzheimer's disease yielding conflicting results; both no difference and an increase in plasma concentrations of alpha beta42 and alpha beta40 in sporadic cases of AD as compared to controls have been reported. Elevated plasma alpha beta42 levels may be detected several years before the onset of symptoms (in mild cognitive impairment stadium). Levels of alpha beta40 and alpha beta42 were measured in plasma from 54 patients with AD, 39 subjects with MCI and 35 controls using a commercially available ELISA. Mean plasma alpha beta42 levels were significantly higher in MCI as compared to both AD (P < 0.001) and control subjects (P < 0.001), while alpha beta40 did not differ between the groups. No correlations were observed between alpha beta levels and age, MMSE scores or gender. According to ROC curve analysis the maximum accuracy in discriminating MCI versus both controls and AD subjects has been achieved using a cut-off value of 3.8. 相似文献
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The UTX gene escapes X inactivation in mice and humans 总被引:7,自引:3,他引:7
Greenfield A; Carrel L; Pennisi D; Philippe C; Quaderi N; Siggers P; Steiner K; Tam PP; Monaco AP; Willard HF; Koopman P 《Human molecular genetics》1998,7(4):737-742
We recently have identified a ubiquitously transcribed mouse Y chromosome
gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A
peptide derived from the UTY protein confers H-Y antigenicity on male
cells. Here we report the characterization of a widely transcribed X-linked
homologue of Uty , called Utx , which maps to the proximal region of the
mouse X chromosome and which detects a human X-linked homologue at Xp11.2.
Given that Uty is ubiquitously transcribed, we assayed for Utx expression
from the inactive X chromosome (Xi) in mice and found that Utx escapes X
chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the
mouse X chromosome have been reported previously to escape inactivation.
The human UTX gene was also found to be expressed from Xi. We discuss the
significance of these data for our understanding of dosage compensation of
X-Y homologous genes in humans and mice.
相似文献
6.
Pathology and Immunocytochemistry of a Kuru Brain 总被引:1,自引:0,他引:1
Johannes A. Hainfellner Pawel P. Liberski Don C. Guiroy Larisa Cervénaková Paul Brown D. Carleton Gajdusek Herbert Budka 《Brain pathology (Zurich, Switzerland)》1997,7(1):547-553
We report here results of modern staining techniques including anti-prion protein (PrP) immunocytochemistry to a set of archival brain specimens of a 16 year-old male who died from kuru in 1967. Brain suspensions transmitted disease to chimpanzees and New World monkeys. The PrP gene is homozygous for valine at the polymorphic codon 129. Histology shows neuronal loss, spongiform change, and astrogliosis. Lesions are maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, striatum, and thalamus, and are accentuated in middle and deep cerebral cortical layers. PrP accumulates as diffuse synaptic type deposits and mostly unicentric plaques. PrP deposition is maximal in parasagittal and interhemispheric areas of frontal, central and parietal cortex, cingulate cortex, basal ganglia, and cerebellar cortex. Plaques are prominent in the striatum, thalamus, and granular layer of cerebellar cortex. Meticulous examination reveals only rare "florid" plaques with surrounding vacuolation.
We conclude that 1) pathology including immunomorphology of PrP deposition in this kuru brain is within the lesion spectrum of Creutzfeldt-Jakob disease although plaques are unusually prominent and widespread; 2) kuru does not share the neuropathological hallmarks of the new Creutzfeldt-Jakob disease variant recently reported in the UK and France; 3) topographic prominence of PrP deposition parallels that of spongiform change and/or astrogliosis. 相似文献
We conclude that 1) pathology including immunomorphology of PrP deposition in this kuru brain is within the lesion spectrum of Creutzfeldt-Jakob disease although plaques are unusually prominent and widespread; 2) kuru does not share the neuropathological hallmarks of the new Creutzfeldt-Jakob disease variant recently reported in the UK and France; 3) topographic prominence of PrP deposition parallels that of spongiform change and/or astrogliosis. 相似文献
7.
L1 knockout mice show dilated ventricles, vermis hypoplasia and impaired exploration patterns 总被引:8,自引:3,他引:8
Fransen E; D'Hooge R; Van Camp G; Verhoye M; Sijbers J; Reyniers E; Soriano P; Kamiguchi H; Willemsen R; Koekkoek SK; De Zeeuw CI; De Deyn PP; Van der Linden A; Lemmon V; Kooy RF; Willems PJ 《Human molecular genetics》1998,7(6):999-1009
L1 is a neural cell adhesion molecule mainly involved in axon guidance and
neuronal migration during brain development. Mutations in the human L1 gene
give rise to a complex clinical picture, with mental retardation,
neurologic abnormalities and a variable degree of hydrocephalus. Recently,
a transgenic mouse model with a targeted null mutation in the L1 gene was
generated. These knockout (KO) mice show hypoplasia of the corticospinal
tract. Here we have performed further studies of these KO mice including
magnetic resonance imaging of the brain, neuropathological analysis and
behavioral testing. The ventricular system was shown to be abnormal with
dilatation of the lateral ventricles and the 4th ventricle, and an altered
shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the
KO mice is hypoplastic. Their exploratory behavior is characterized by
stereotype peripheral circling reminiscent of that of rodents with induced
cerebellar lesions.
相似文献
8.
Waliś A Bratosiewicz J Sikorska B Brown P Gajdusek DC Liberski PP 《Journal of comparative pathology》2003,129(2-3):213-225
This report describes the ultrastructural changes in the optic nerves of (1) hamsters infected with the Echigo-1 strain of Creutzfeldt-Jakob disease (CJD), (2) hamsters infected with the 263K or 22C-H strain of scrapie, and (3) mice infected with the Fujisaki strain of Gerstmann-Str?ussler-Scheinker disease (GSS). Vacuolation of myelinated fibres was present in the myelin sheaths, with splitting of myelin lamellae. These vacuoles contained typical secondary vacuoles and curled membrane fragments. Myelinated fibre vacuolation was also accompanied by an exuberant cellular reaction consisting of macrophages containing numerous mitochondria, abundant rough endoplasmic reticulum, and secondary lysosomes filled with digested myelin debris and other electron-dense material. Within macrophages, myelin fragments undergoing active digestion, lyre-like bodies and paracrystalline inclusions were frequently noted. Astrocytes and their processes were prominent; glial filaments and many mitochondria were readily detected. Proliferation of inner mesaxons was observed. Cross-sectional profiles of innumerable myelinated fibres contained membranous organelles continuous with the inner lamellae of the oligodendroglial cells. The proliferations of inner mesaxons formed whorls and loops, and intrusion of the membranous tongue of the inner mesaxon into the axoplasm was occasionally observed; dystrophic neurites were relatively numerous. In mice infected with the Fujisaki strain of GSS, fibres had undergone demyelination with stripping of the myelin lamellae, while others showed vesicular myelin degeneration. 相似文献
9.
J. Z. Nowak A. Bogucki P. Liberski 《Journal of neural transmission (Vienna, Austria : 1996)》1986,65(3-4):187-192
Summary The histamine (Hi) content and the activity of L-histidine decarboxylase (HD) in brains of scrapie infected hamsters were measured. No significant changes in Hi levels in particular brain areas were found when compared to controls. Decreased activity of HD was found in hypothalamus (p<0.02). Increased activity of the enzyme was observed in rest of brain, which consisted mainly of thalamus and striatum (p<0.05). 相似文献
10.
Waliś A Liberski PP 《Folia neuropathologica / Association of Polish Neuropathologists and Medical Research Centre, Polish Academy of Sciences》1999,37(4):281-282
The Echigo-1 strain of CJD was isolated by Mori and colleagues (1989) from a case of 33-year-old female with a panencephalopathic type of CJD. An incubation period following intracerebral inoculation of hamsters with 10% cleared suspension of the Echigo-1-affected brain was approximately six months. We report here ultrastructural changes which are comparable with those in the white matter of another panencephalopathic type of CJD, the Fujisaki strain of CJD (GSS) passaged in mice. Vacuoles developed within myelinated axons: within axoplasm or within the myelin sheath and these were accompanied by exuberant reaction of macrophages and hypertrophic astrocytes. Axons underwent Wallerian degeneration and dystrophic neurites were also seen. Most important, we observed proliferation of inner mesaxons. Cross-sectional profiles of innumerable myelinated fibers contained membranous organelles which were continuous with the inner lamellae of the oligodendroglial cells. These unusual proliferations of inner mesaxon formed whorls and elaborated loops. In some axons, proliferation was so severe that loops of mesaxon filled the whole cross-section of the axon. Occasionally, we observed intrusion of the membranous tongue of the inner mesaxon into axoplasm. This study presents a second panencephalopathic model of CJD available in small laboratory rodents. It is important because this is the only such model in hamsters and it may be used for comparative studies of different strains of agent in the same host; thus far only mouse and hamster model have been available for comparative studies. 相似文献