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71.
Immunoelectron microscopic localization of the ubiquitin-activating enzyme E1 in HepG2 cells.
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A L Schwartz J S Trausch A Ciechanover J W Slot H Geuze 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(12):5542-5546
As the first enzyme in the ubiquitin system the ubiquitin-activating enzyme E1 plays a pivotal role in all pathways of protein ubiquitination. In an effort to learn more about the cell biology of this pathway, we have purified the 110-kDa enzyme to homogeneity and generated a panel of distinct monoclonal antibodies to it. Using quantitative electron microscopic immunolocalization with these anti-E1 monoclonal antibodies, we find that E1 is abundant both within the cytoplasm and nucleus. Within the cytoplasm, E1 was found throughout the cytoplasmic volume as well as enriched along the cytoplasmic face of the rough endoplasmic reticulum and associated with the dense material along the desmosomal junctions. E1 was also found associated with the cytoplasmic surface of endosomal/lysosomal vacuoles. Interestingly, E1 was also found within the mitochondria. The lumen of rough endoplasmic reticulum, Golgi complex, endosomes, and lysosomes were negative. The specific localization of E1 to distinct subcellular organelles suggests that E1 may play multiple physiological roles within the cell. 相似文献
72.
Bone marrow disorders: characterization with quantitative MR imaging 总被引:10,自引:0,他引:10
Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates. 相似文献
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About 1-2% of the human genome is allocated to production of receptors for the olfactory epithelium-a hint as to the possible importance of this chemical sense, which includes two anatomically distinct systems: the main olfactory system with sensory cells located in the upper part of the nasal cavity, and the vomero-nasal organ with sensory cells on the nasal septum. In adults, individual odours may influence mate preferences and a growing body of evidence indicates that naturally occurring odours play an important role in the mediation of the infant's behaviour. Even foetal olfactory learning seems to occur and breast odours from the mother exert a pheromone-like effect at the newborn's first attempt to locate the nipple. Newborns are generally responsive to breast odours produced by lactating women. Olfactory recognition may be implicated in the early stages of the mother-infant attachment process, when the newborns learn to recognize the own mother's unique odour signature-a process possibly facilitated by the high norepinephrine release and the arousal of the locus coeruleus at birth. New knowledge about human odour physiology may have diagnostic and therapeutic implications-the initiation and stabilization of breastfeeding and termination of apnoeic spells are mentioned as examples. 相似文献
76.
ABSTRACT: In-vitro autoradiography was utilized to compare the distribution of 2[125 I]iodomelatonin binding sites or putative melatonin receptors in the gastrointestinal tracts of humans, guinea pigs, mice, rats, hamsters, rabbits, ducks, chickens, pigeons, and quail. In humans, binding was detected in the mucosa of the colon, caecum, appendix, and on their blood vessels but not in the ileum. In the other mammals, significant binding was only demonstrated in the mucosa of the rabbit rectum, mouse colon, mouse rectum, and guinea pig ileum. The distribution of 2[125 I]iodomelatonin binding in the avian gut varied with species. In the esophagus, binding was present in the lamina propria and blood vessels of all four birds. However, only the lamina propria of the chicken and quail proventriculus and ventriculus showed positive binding. For the duodenum and ileum, binding was very strong in the duck lamina propria, weak in the chicken lamina propria, and absent in the quail. In contrast, the pigeon muscle layer was weakly positive. The most striking species difference was found in the caecum where the duck lamina propria showed very strong binding, while the chicken lamina propria was only weakly positive. Conversely, the caecal muscle layer was strongly positive in chicken and quail but negative in duck and pigeon. In the rectum, a similar but less intense pattern of distribution was observed. The tremendous diversity in the distribution of 2[125 I]iodomelatonin binding sites in the gastrointestinal tract is in accord with the hypothesis that melatonin may serve different functions in the gut of different species. 相似文献
77.
The clinical features of immunoglobulin light-chain (AL) amyloidosis with heart involvement 总被引:9,自引:0,他引:9
Dubrey SW; Cha K; Anderson J; Chamarthi B; Reisinger J; Skinner M; Falk RH 《QJM : monthly journal of the Association of Physicians》1998,91(2):141-157
We reviewed clinical presentation, investigations, therapy, prognosis and
outcome of 232 patients with primary (AL) cardiac amyloidosis. There were
142 men and 90 women. Median age at presentation was 59 years (range
29-85). AL heart disease was unusual both in patients under the age of 40
(3.0%) and in non-Caucasians (6.5%). Fatigue and weakness were the
commonest presenting symptoms. Hallmark features of periorbital ecchymoses
and macroglossia were present in 12.5% and 27.2%, respectively. AL cardiac
amyloidosis was unusual in isolation (3.9%), and most frequently patients
had features of multiorgan dysfunction; heavy proteinuria and features of
malabsorption predominating in this respect. Heart involvement represents
the worst prognostic indicator, with a median survival from diagnosis of
1.08 years, falling to 0.75 years with the onset of heart failure. Current
therapeutic procedures appear to prolong survival, with left ventricular
wall thickness, mass and ejection fraction on echocardiography and late
potentials on signal averaged electrocardiography of use in prognostic
stratification. Cardiac involvement from AL amyloidosis is rapidly fatal.
It should be suspected in all patients with heart failure who have wall
thickening on echo, normal chamber sizes, low EKG voltages and evidence
suggesting a multisystem disease.
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用药物—染料生成复合物的原理,建立了双氢埃托啡的燐光分析法?椒槊?可检测2ng。适用于动物血药、脑药分析。兔im0.1,0.2,1mg/kg双氢埃托啡后1与5min。血药,脑药与剂量成比例关系,其回归方程为:血药:Y=100.6X+17.73(1min), Y=367.8X+4.34(5min); 脑药:Y=5363 X+275.4(1 min),Y=6084 X+1022(5 min) 式中Y=药物浓度(ng/ml血或ng/g脑),X=双氢埃托啡剂量(mg/kg)。 相似文献