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141.
In 1982, Mesulam drew attention to a clinical picture characterized by slowly progressive aphasia without dementia, and since then, there have been many such reports. Recently, there have been 30 reports of slowly progressive apraxia. However, the nature of this apraxia is not uniform. We now report a patient with slowly progressive dressing and constructional apraxia. The patient is a 60-year-old right-handed woman with a 2-year history of a slowly progressive praxic disturbance. On admission, she was alert and aware of this difficulty. A neurological examination disclosed mild rigidity and myoclonus in her left hand. A neuropsychological assessment disclosed severe dressing apraxia, which was unlikely to be caused by dementia and moderate constructional apraxia. Her dressing apraxia was manifested in upper limbs, neck, trunk and lower limbs. However, she could express verbally the action of dressing. She also showed mild limb-kinetic apraxia, but neither ideational apraxia nor ideomotor apraxia was present. Aphasia and agnosia were also absent. On an MRI, the bilateral cerebral hemispheres were atrophic (right > left). A 99m-Tc ECD SPECT revealed decreased uptake in the right cerebral hemisphere and left frontal lobe, and an EEG showed slow waves over the right cerebral hemisphere. There have been 30 reports of slowly progressive apraxia. Most of these cases presented with slowly progressive clumsiness in one or both hands as an initial symptom, followed by constructional, ideomotor or dressing apraxia. Our patient differed from these cases in that dressing and constructional apraxia progressed slowly without any other apraxia except only mild limb-kinetic apraxia. There was a similarity between dressing apraxia of our patient and that of Marie's and Brain's original cases.  相似文献   
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Recently, mutations of the GTP-cyclohydrolase I (GTP-CH I) gene, which catalyzes the first step in the tetrahydrobiopterin (BH4) biosynthesis, were discovered in Japanese patients with hereditary progressive dystonial/dopa-responsive dystonia (HPD/DRD). However, it has not been confirmed that non-Japanese patients also contain mutations in the same gene, or whether these mutations are specific to HPD/DRD. In this study, two novel nonsense mutations in exon 1 of the GTP-CH I gene and a new mutation at the splice acceptor site of intron 1 were identified in an autopsied case of English-Irish descent and 2 Japanese patients with HPD/DRD. In the latter, cerebrospinal fluid (CSF) neopterin levels (which may reflect the GTP-CH I activity in the brain) were reduced to 18% and 37% of controls. A therapeutic trial of oral BH4 was ineffective, however, in a genetically proven patient. In contrast, no mutations in any exons of the GTP-CH I gene were found in 2 patients with early-onset parkinsonism with dystonia (EOP-D) who developed dopa-responsive parkinsonism and dystonia at 6 and 8 years old, respectively. Neopterin levels in CSF were well preserved in 6 EOP-D patients. These data suggest that, among patients of different racial backgrounds, the pathogenesis of HPD/DRD, unlike EOP-D, involves partial reduction of the brain GTP-CH I activity consequent to mutations in the GTP-CH I gene. Measurement of CSF neopterin concentration may be useful for the differential diagnosis between HPD/DRD and EOP-D.  相似文献   
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Previously we reported that the consecutive injection of lipopolysaccharide (LPS) into LPS-sensitized mice for the generalized Shwartzman reaction (GSR) appeared to induce the injury of renal tubular epithelial cells via apoptosis. The aim of this study was to characterize the mechanism of renal tubular epithelial cell injury in GSR. The expression of Fas and Fas ligand was immunohistochemically detected on renal tubular epithelial cells from GSR-induced mice, although neither Fas nor Fas ligand was found in cells from untreated control mice or in cells from mice receiving a single injection of LPS. GSR-induced renal tubular epithelial cell injury was produced in neither Fas-negative MRL-lpr/lpr mice nor Fas ligand-negative MRL-gld/gld mice. The administration of anti-gamma interferon antibody together with a preparative injection of LPS prevented the expression of Fas and Fas ligand and the apoptosis of renal tubular epithelial cells. A provocative injection of tumor necrosis factor alpha into LPS-sensitized mice augmented Fas and Fas ligand expression and the apoptosis of renal tubular epithelial cells. The administration of tumor necrosis factor alpha to interleukin-12-sensitized mice resulted in Fas and Fas ligand expression and the apoptosis. Sensitization with interleukin-12 together with anti-gamma interferon antibody did not cause the apoptosis of renal tubular epithelial cells. It was suggested that the Fas/Fas ligand system probably plays a critical role in the development of renal tubular epithelial cell injury through apoptotic cell death.  相似文献   
147.
15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) is an endogenous peroxisome proliferator-activated receptor γ (PPARγ) agonist that suppresses progressive matrix deposition; however, little is known about the effects of 15d-PGJ2 on human peritoneal mesothelial cells (HPMCs). We investigated the following: (i) the expression of PPARγ; (ii) the effect of 15d-PGJ2 on angiotensin II (Ang II)-induced fibronectin (FN) expression and secretion; (iii) the effect of 15d-PGJ2 (with or without Ang II and with or without the specific PPARγ antagonist GW9662) and pioglitazone, a synthetic PPARγ agonist, on hepatocyte growth factor (HGF) expression and secretion; (iv) the effect of HGF on Ang II-induced FN expression and secretion; (v) the expression of c-Met (a specific HGF receptor) and its phospho-signal; and (vi) the involvement of HGF in the effect produced by 15d-PGJ2 using selective c-Met inhibitor PHA-665752. The presence of PPARγ was detected by western blot analysis. 15d-PGJ2 inhibited Ang II-induced FN expression and increased HGF expression, even in the presence of Ang II. This effect of HGF expression was completely prevented by co-treatment with GW9662. Additionally, upregulation of HGF secretion induced by 15d-PGJ2 and HGF production induced by pioglitazone was revealed. We demonstrated the presence of c-Met, and presented evidence that HGF inhibits Ang II-induced FN expression and activates phosphorylation of c-Met, which is blocked by PHA-665752; 15d-PGJ2 also activated c-Met phosphorylation. Furthermore, PHA-665752 attenuates the inhibitory effects of 15d-PGJ2 on FN secretion. These findings suggest that 15d-PGJ2 has a novel and potent antifibrotic effect in HPMC and this action is likely mediated by HGF.  相似文献   
148.
The characteristics of nine monoclonal antibodies (MoAbs) produced using the uninduced cells of a human erythroleukemia line (HEL) as immunogen are described. These antibodies were grouped into four categories by their differences in recognition of normal cells and cells of hemopoietic cell lines. The four MoAbs of group A recognize determinants that are expressed in a large proportion of normal bone marrow cells and other mature cells. The two MoAbs of group B (53/5, 53/6) and the two MoAbs of group C (54/23, 54/39) recognize small proportions of bone marrow cells, whereas the single MoAb of group D (53/10) essentially recognizes only HEL cells. Competition experiments revealed two pairs of competing Abs (53/5 and 53/6; 54/23 and 54/39). In complement-dependent cytotoxicity of progenitors, 53/6 produced 90%-100% inhibition of CFU-E, BFU-E, and CFU-C growth; 54/39 30%-60% inhibition of BFU-E and CFU-C growth; 53/10 produced a variable degree of inhibition of CFU-E and BFU-E. Cell sorting using 53/6 resulted in approximately a 10-12-fold enrichment of CFU-E, BFU-E, and CFU-C among the positive cells. Cell sorting with 54/23 resulted in recovery of over 90% of BFU-E and 100% of CFU-C among the 23.5% of sorted cells showing strong or intermediate positivity. These findings suggest that HEL cells possess surface characteristics that are expressed in several classes of hemopoietic progenitors.  相似文献   
149.
Experimental infections of mice with a Sendai virus temperature-sensitive (ts) mutant (HVJ-pB) were studied. Infection with the ts mutant induced the priming effect of interferon production and both humoral and cellular immune responses, although the ts mutant virus neither multiplied satisfactorily in the respiratory tracts of mice nor caused appreciable histopathologic lesions. Inoculation with the ts mutant protected mice from subsequent challenge with a parental wild-type virus. The efficacy of this protection began as little as 1 day after vaccination and continued for at least 12 weeks. It is suggested that serum antibodies were efficacious in the nasal turbinates, while specific immune spleen cells act more protectively in the lungs.  相似文献   
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