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101.
102.
Thompson PM; Moussai J; Zohoori S; Goldkorn A; Khan AA; Mega MS; Small GW; Cummings JL; Toga AW 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(6):492-509
The onset of Alzheimer's disease (AD) is accompanied by a complex and
distributed pattern of neuroanatomic change, difficult to distinguish
clinically from dynamic alterations in normal aging. Extreme variations in
the sulcal patterns of the human cortex have made it difficult to identify
diffuse and focal variations in cortical structure in neurodegenerative
disease. We report the first comprehensive 3D statistical analysis of deep
sulcal structure in vivo, in both normal aging and dementia.
High-resolution 3D T1-weighted fast SPGR (spoiled GRASS) MRI volumes were
acquired from 10 patients diagnosed with AD (NINCDS-ARDRA criteria; age:
71.9 +/- 10.7 years) and 10 normal subjects matched for age (72.9 +/- 5.6
years), gender, educational level and handedness. Scans were digitally
transformed into Talairach stereotaxic space. To determine specific
patterns of cortical variation in dementia patients, 3D average and
probabilistic maps of primary deep sulci were developed for both normal and
AD groups. Major sulci (including supracallosal, cingulate, marginal,
parieto-occipital, anterior and posterior calcarine sulci, and Sylvian
fissures) were modeled as complex systems of 3D surfaces using a
multi-resolution parametric mesh approach. Variations and asymmetries in
their extents, curvature, area and surface complexity were evaluated.
Three- dimensional maps of anatomic variability, structural asymmetry and
local atrophy indicated severe regionally selective fiber loss in AD. A
midsagittal area loss of 24.5% at the corpus callosum's posterior midbody
(P < 0.025) matched increases in structural variability in corresponding
temporo-parietal projection areas. Confidence limits on 3D cortical
variation, visualized in 3D, exhibited severe increases in AD from 2 to 4
mm at the callosum to a peak SD of 19.6 mm at the posterior left Sylvian
fissure. Normal Sylvian fissure asymmetries (right higher than left; P <
0.0005), mapped for the first time in three dimensions, were accentuated in
AD (P < 0.0002), and were greater in AD than in controls (P < 0.05).
Severe AD-related increases in 3D variability and asymmetry may reflect
disease-related disruption of the commissural system connecting bilateral
temporal and parietal cortical zones, regions known to be at risk of early
metabolic dysfunction, perfusion deficits and selective neuronal loss in
AD.
相似文献
103.
Computed tomography of the breast. A preliminary report 总被引:2,自引:0,他引:2
Chang CH; Sibala JL; Gallagher JH; Riley RC; Templeton AW; Beasley PV; Porte RA 《Radiology》1977,124(3):827
104.
AW Segal 《Journal of clinical pathology》1983,36(1):119-120
105.
Spinal arachnoid cysts in children 总被引:3,自引:0,他引:3
Five cases of benign spinal arachnoid cysts in children are described with their clinical, neuroradiological, surgical and pathological findings. Intraspinal benign arachnoid cysts may be confidently diagnosed myelographically when there is complete or partial obstruction with multiple oily contrast/cerebrospinal fluid levels as in 3 cases in this series. The multiple fluid levels are probably produced by multiple cysts or a cyst loculated due to partial compression by arachnoid bands either related to the normal septum posticum, congenital or acquired adhesion rather than to trabeculations within the cyst. In this series, the origin of the cysts is considered to be congenital. 相似文献
106.
107.
目的 检验磁共振胆道成像作为诊断原发性硬化性胆管炎的可选择性方法的价值。病例和方法 20例原发性硬化性胆管炎行内镜逆行性胆道造影和磁共振胆道成像。评价肝内外胆道显示率和病理性改变。结果 胆管和肝管壁不规则(6/7),所有病例均存在胆道狭长或扩张,磁共振胆道成像(MRCP)显示肝外胆管多段狭长和扩张较好,而ERCP因受图像分辨率的限制,仅可显示胆管周围分支的中断。MRCP显示早期原发性硬化性胆管炎的胆道系统壁不规则改变亦较ERCP稍好。结论 原发性硬化性胆管炎早期诊断,MRCP可以作为ERCP的补充,而就晚期原… 相似文献
108.
109.
Noncycling state of peripheral blood progenitor cells mobilized by granulocyte colony-stimulating factor and other cytokines 总被引:2,自引:8,他引:2
Incubation with high doses of tritiated thymidine in vitro was used to determine the percent of progenitor cells in the S phase of the cell cycle. Peripheral blood (PB), bone marrow (BM), and spleen populations from mice injected with granulocyte colony-stimulating factor (G-CSF) at 5 micrograms/day for 5 days and BM cells from uninjected littermates were assayed. Although the percentage of progenitor cells in S phase in the marrow (47% +/- 5%) and spleen (52% +/- 9%) was increased significantly in G-CSF-treated mice, only a small proportion of PB progenitor cells (PBPC) were in S phase (7% +/- 4%). In normal human subjects injected with G-CSF at 5 or 10 micrograms/kg/d, the proportions of PB myeloid (-1 +/- 4%) and erythroid (0% +/- 8%) progenitor cells in S phase were very low compared with the proportion of myeloid progenitor cells in S phase in normal BM (34% +/- 10%). Similarly, the large majority of steady-state PBPC and PBPC mobilized by interleukin-3 in combination with either granulocyte-macrophage colony-stimulating factor or G-CSF were also found not to be in S phase. Experiments indicated that the low percentages of PBPC in S phase were not ascribable either to inhibitory elements in the blood or to reduced responsiveness to growth factors. 相似文献
110.