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排序方式: 共有981条查询结果,搜索用时 15 毫秒
911.
Cognitive deficits associated with frontal-lobe infarction in children with sickle cell disease 总被引:3,自引:1,他引:2
KE Watkins MSc D E M Hewes MRCP A. Connelly PhD BE Kendall FRCR D P E Kingsley FRCR J E P Evans FRCP DG Gadian DPhil F. Vargha-Khadem PhD FJ Kirkham FRCP 《Developmental medicine and child neurology》1998,40(8):536-543
This study examined the cognitive manifestations of frontal-lobe infarction in a population of children with sickle cell disease (SCD). Forty-one patients with SCD underwent MRI. Five patients with stroke symptoms had large infarcts encroaching on the tissue of the frontal lobes. Four patients without symptoms had smaller frontal-lobe infarcts. The patients with stroke were significantly impaired on measures of intelligence, memory, and frontal-lobe function (Wisconsin Card Sorting Test, WCST) compared with both the patients with normal MRI scans ( N = 30) and a group of sibling controls ( N = 15), who did not differ from each other. Patients with covert infarction obtained scores on the intelligence tests and the WCST that fell in between those of the stroke patients and the other two groups. This trend toward impairment suggests that patients with covert infarction are at similar risk for cognitive deficits to those with stroke. 相似文献
912.
Blood lipid concentrations and other cardiovascular risk factors: distribution, prevalence, and detection in Britain 总被引:19,自引:0,他引:19
J I Mann B Lewis J Shepherd A F Winder S Fenster L Rose B Morgan 《British medical journal (Clinical research ed.)》1988,296(6638):1702-1706
To establish the distribution of blood lipid concentrations and the prevalences of other risk factors for cardiovascular disease in Britain 12,092 men and women aged 25-59 in Glasgow, Leicester, London, and Oxford were studied. Subjects were selected by opportunistic case finding, in which patients consulting their general practitioner for any reason were offered a health check by appointment, or random selection from age-sex registers, in which an invitation for a health check was posted. The overall rate of response was 73%, being 91-94% by opportunistic case finding and 36-63% by random selection. At the health check subjects answered a brief questionnaire about risk factors for cardiovascular disease, and their height, weight, and blood pressure were recorded; a blood sample was taken for measuring plasma concentrations of cholesterol, triglyceride, high density lipoprotein cholesterol, and glucose. The mean cholesterol concentrations were 5.9 (SD 1.2) and 5.8 (1.2) mmol/l in men and women, respectively. In London the mean value was 5.5 (1.2) mmol/l for both men and women and was significantly lower than mean values in the three other centres, among which there were no significant differences. In men and women aged 25-29 concentrations were similar but they increased in men until the age of 45-49, after which they showed no further increase; in women concentrations did not increase until the age of 40-44 and by the age of 50-59 values were higher than in men. Mean triglyceride concentrations were significantly higher in men than in women (1.8 (1.4) v 1.3 (0.9) mmol/l, respectively), and trends with age were similar to those for cholesterol concentrations, except that at no age were values higher in women than in men. Mean triglyceride values overall were higher in Glasgow and London than in Oxford and Leicester. Body mass index was higher in Glasgow and London than in the other two centres and correlated with systolic and diastolic blood pressures and triglyceride concentration. In addition, subjects in Glasgow smoked significantly more than those in the other centres. These observations could contribute to the higher rate of coronary heart disease in Glasgow. Plasma lipid concentrations and the prevalences of other risk factors for cardiovascular disease were similar in subjects selected by opportunistic case finding and by random selection. In Britain cholesterol values have changed little during the past 12 years despite dietary recommendations and health education.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
913.
To establish the usual pattern of flow in the circle of Willis in newborns, the authors scanned 53 healthy full-term infants within 3 days of birth with color Doppler imaging. All examinations were performed and images interpreted by the same experienced individuals. The basilar, internal carotid (ICA), and anterior and middle cerebral arteries were seen in all infants. Vertebral, posterior cerebral, superior cerebellar, and posterior communicating (PCoA) arteries were seen in most infants. PCoA flow was from the ICA toward the posterior cerebral artery in 73 (98.6%) of the 74 vessels that were seen. Flow in the anterior communicating artery was seen in six infants, indicating dependence of an anterior cerebral artery on contralateral ICA perfusion. Two pitfalls involving the distal portion of the ICA were noted: This vessel could be confused with the proximal portion of the anterior cerebral artery or cavernous sinus if real-time images were not interpreted carefully. Variant patterns of flow included tortuous basilar arteries (n = 2), reversed PCoA flow (n = 1), and inferior angulation of the proximal portions of the anterior cerebral arteries (n = 2). Color Doppler imaging allows a detailed analysis of the circle of Willis in newborns and detection of some anatomic variations. 相似文献
914.
A cardiac-gated sequence has been developed for functional cardiac imaging. It uses a nonselective 180 degrees preinverting pulse before a spin-echo (SE) readout sequence with an echo time (TE) of 28 msec. In seven healthy volunteers this sequence provided superior wall-to-chamber contrast in end diastole and end systole when compared with the following sequences: SE, TE = 28 msec; SE, TE = 28 msec with dephasing gradients; and SE, TE = 28 msec with presaturation bands. 相似文献
915.
916.
917.
Bressler SL; Gray MD; Sopher BL; Hu Q; Hearn MG; Pham DG; Dinulos MB; Fukuchi K; Sisodia SS; Miller MA; Disteche CM; Martin GM 《Human molecular genetics》1996,5(10):1589-1598
Using the yeast two hybrid system, a mouse embryo cDNA library was screened
for proteins that interact with the C-terminus of the human beta-amyloid
precursor protein (beta PP). A fusion protein was identified that interacts
specifically with the cytoplasmic domain of beta PP and does not interact
with the beta-amyloid region. The protein encoded by this partial mouse
cDNA is identical to the C-terminus of the rat Fe65 protein. This mouse
protein also interacts with the homologous C-terminal domains of the mouse
amyloid precursor-like proteins, APLP1 and APLP2. These conserved
cytoplasmic regions contain a common amino acid motif, Asn-Pro-Thr-Tyr,
which has previously been shown to influence both the secretion and
internalization of beta PP. Fe65 has been implicated in regulatory and cell
signaling mechanisms because it contains two different motifs involved in
protein binding, a WW domain (a variant of Src homology 3 domains) and a
phosphotyrosine interaction domain (PID). Interestingly, the PID domain
binds to the same motif present in the conserved cytoplasmic domains of the
beta PP and beta PP-like proteins. RNA analyses reveal that Fe65 is
predominantly expressed in brain and in the regions most affected by
Alzheimer's disease (AD)-associated neuropathology. The human Fe65 mRNA was
cloned from a fetal brain cDNA library. The message encodes a protein of
735 amino acids that is 95% identical to the rat Fe65 protein. The human
Fe65 gene was mapped on human metaphase chromosomes to band 11p15 using
fluorescence in situ hybridization.
相似文献
918.
919.
920.
DG Barr JM Kirk M al Howasi RJ Wanders RB Schutgens 《Archives of disease in childhood》1993,68(3):415-417
An infant with the characteristic phenotype of classical rhizomelic chondrodysplasia punctata was found to have an isolated deficiency of the peroxisomal enzyme acyl CoA dihydroxyacetone phosphate acyltransferase (DHAP-AT). All other peroxisomal functions measured were found to be normal. Previously described in one other case report, this confirms the existence of another distinct form of peroxisomal disorder characterised biochemically by a deficiency in de novo plasmalogen biosynthesis only. 相似文献