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121.
Clear cell carcinoma has been described in numerous anatomic sites. Renal location is the most frequent. The occurrence in the gallbladder is exceptional. We report the case of a 71-Year-old woman who presented with sub-acute angiocrolitis. Computer tomographic scan revealed a polypoid mass close to the neck of the gallbladder; there was no renal lesion. Histological analysis of the gallbladder showed a primitive clear cell carcinoma with a papillary pattern associated with carcinoma in situ. Immunohistochemical study confirmed the primitive character of the tumor, characterized by an expression of KL-1, EMA and ACE and an absence of vimentin, CD 10 and CD15. Clear cell carcinomas of the gallbladder are uncommon neoplasms which could only be diagnosed on clinical, histological and immunohistochemical arguments.  相似文献   
122.
123.
Three new missense mutations (H15D, A83D, and A179D) and a new splicing defect (573 + 1G→A) in the 5′ splice site of intron 5 were among six mutant adenosine deaminase (ADA) alleles found in three unrelated patients with severe combined immunodeficiency disease, the most common phenotype associated with ADA deficiency. When expressed in vitro, the H15D, A83D, and A179D proteins lacked detectable ADA activity. The splicing defect caused skipping of exon 5, resulting in premature termination of translation and a reduced level of mRNA. H15D is the first naturally occurring mutation of a residue that coordinates directly with the enzyme-associated zinc ion. Molecular modeling based on the atomic coordinates of murine ADA suggests that the D15 mutation would create a cavity or gap between the zinc ion and the side chain carboxylate of D15. This could alter the ability of zinc to activate a water molecule postulated to play a role in the catalytic mechanism. A83 and A179 are not directly involved in the active site, but are conserved residues located respectively in a helix 4 and β strand 4 of the α/β barrel. Replacement of these small hydrophobic Ala residues with the charged, more bulky Asp side chain may distort ADA structure and affect enzyme stability or folding.© 1995 wiley-Liss, Inc.  相似文献   
124.
We report two patients, born of consanguineous parents, affected by a disorder resulting in mild growth retardation. Hallmarks are amelogenesis imperfecta (absence of the enamel cap) associated with brachyolmia-like anomalies: platyspondyly with short pedicles, narrow intervertebral and interpedicular distances, rectangular-shaped vertebrae with posterior scalloping and herniation of the nuclei, and broad femoral necks. Inheritance appears to be autosomal recessive.  相似文献   
125.
Based on two independent personal cases and a pair of sibs from the literature, we delineate a new category of bone dysplasia with cup-shaped large metaphyses, for which the name metaphyseal acroscyphodysplasia is suggested. The main clinical features are severe growth retardation, micromelia predominating in the lower limbs, knee flexion, and severe brachydactyly. The radiological aspect of the knees is very specific: the lower femoral and upper tibial epiphyses embed themselves in their metaphyses, which are severely cup-shaped. Premature central epiphyso-metaphyseal fusion and gross deformation, or even coalescence, of the femoral condyles may occur. The femoral diaphyses are very short and broad, and there is progressive coxa valga. Bowed and/or short stubby tibiae with cone-shaped metaphyses, and varus deformity of the tibio-astragalian joint are other features. Slight deformations of the long bones occur in the upper limb. Severe brachydactyly, brachymesophalangy, phalangeal and metacarpal cone-shaped epiphyses and irregular, bent and shortened diaphyses are the main signs of hand involvement. Psychomotor retardation is present in 3/4. Autosomal recessive inheritance is likely.  相似文献   
126.
We report on a boy with a combination of manifestations reminiscent of aminopterin embryopathy: brachyturricephaly with craniosynostosis, poorly mineralised vault, upslanted palpebral fissures, malar hypoplasia, high-arched palate, micrognathia, thick, abnormal auricles, ASD, minor hand anomalies, growth and mental ratardation. Three convincing cases of “Aminopterin Syndrome Sine Aminopterin” have been reported (the fourth case possibly having the Juberg–Hayward syndrome). Variability and heterogeneity of cases with apparent aminopterin embryopathy are discussed. © 1993 Wiley-Liss, Inc.  相似文献   
127.
It is assumed that somatosensory input is required for motor learning and recovery from focal brain injury. In rodents and other mammals, corticocortical projections between somatosensory and motor cortices are modified by patterned input. Whether and how motor cortex function is modulated by somatosensory input to support motor learning is largely unknown. Recent human evidence suggests that input changes motor excitability. Using transcranial magnetic stimulation (TMS), this study tested whether motor cortex excitability is affected by patterned somatosensory stimulation in rodents. Motor potentials evoked in gastrocnemius muscles in response to TMS (MEP(TMS)) and to cervical electrical stimulation (MEP(CES)) were recorded bilaterally. Initially, the first negative peak of the MEP(TMS) was identified as a cortical component because it disappeared after decortication in three animals. Subsequently, we studied the effects of 2 h of electrical stimulation of one sciatic nerve on the cortical component of the MEP(TMS), i.e., on motor cortex excitability. After stimulation, its amplitude increased by 117 +/- 45% ( P<0.01) in the stimulated limb. A significantly smaller effect was found in the unstimulated limb ( P<0.02) and no effect was observed in unstimulated control animals. The subcortically evoked MEP(CES) were not affected by stimulation. It is concluded that somatosensory input increases motor excitability in rat. This increase outlasts the stimulation period and is mediated by supraspinal structures, likely motor cortex. Modulation of motor cortex excitability by somatosensory input may play a role in motor learning and recovery from lesion.  相似文献   
128.
Gratacos et al. [2001: Cell 106:367-379] described an interstitial duplication dup(15)q24q26 (DUP25) in patients with anxiety disorders; this duplication was found in approximately 90% of patients and in 7% of controls. In order to determine if DUP25 is present in additional individuals susceptible to panic attacks, we tested 44 patients with anxiety disorders, using probes 251c23 and 216c14 mapping in the 15q24 and 15q26 region. We have not detected any DUP25. Our results suggest that DUP25 is not common in people with anxiety disorders in the population tested here.  相似文献   
129.
To investigate the possibility of superantigen-mediated deletions of T cells expressing particular T cell receptor Vβ (TcR Vβ) gene segments during human immunodeficiency virus (HIV) infection, TcR Vp usage in CD4+ and CD8+ subsets was analyzed in a cohort of infants maternally infected by HIV and in a group of healthy neonates. We used a semi-quantitative anchored polymerase chain reaction technique together with cytofluorographic analysis with anti-Vβ monoclonal antibodies. The representation of the 24 vβ families in CD4+ and CD8+ T cells from normal neonates was very similar to that in adults. Preferential expression of Vβ2 in the CD4+ subset was observed in both the neonates and in healthy adults. The representation of the 24 Vβ families in peripheral CD4+ T cells from the HIV-infected infants showed no selective vβ deletion, even when the CD4+ subset was globally depleted. Moreover, the main characteristics of the control group (predominance of certain Vβ families and Vβ2 skewing towards the CD4+ subset) were also present in all the HIV-infected infants.  相似文献   
130.
BACKGROUND: DC derived-exosomes are nanomeric vesicles harboring functional MHC/peptide complexes capable of promoting T cell immune responses and tumor rejection. Here we report the feasability and safety of the first Phase I clinical trial using autologous exosomes pulsed with MAGE 3 peptides for the immunization of stage III/IV melanoma patients. Secondary endpoints were the monitoring of T cell responses and the clinical outcome. PATIENTS AND METHODS: Exosomes were purified from day 7 autologous monocyte derived-DC cultures. Fifteen patients fullfilling the inclusion criteria (stage IIIB and IV, HLA-A1+, or -B35+ and HLA-DPO4+ leukocyte phenotype, tumor expressing MAGE3 antigen) were enrolled from 2000 to 2002 and received four exosome vaccinations. Two dose levels of either MHC class II molecules (0.13 versus 0.40 x 1014 molecules) or peptides (10 versus 100 mug/ml) were tested. Evaluations were performed before and 2 weeks after immunization. A continuation treatment was performed in 4 cases of non progression. RESULTS: The GMP process allowed to harvest about 5 x 1014 exosomal MHC class II molecules allowing inclusion of all 15 patients. There was no grade II toxicity and the maximal tolerated dose was not achieved. One patient exhibited a partial response according to the RECIST criteria. This HLA-B35+/A2+ patient vaccinated with A1/B35 defined CTL epitopes developed halo of depigmentation around naevi, a MART1-specific HLA-A2 restricted T cell response in the tumor bed associated with progressive loss of HLA-A2 and HLA-BC molecules on tumor cells during therapy with exosomes. In addition, one minor, two stable and one mixed responses were observed in skin and lymph node sites. MAGE3 specific CD4+ and CD8+ T cell responses could not be detected in peripheral blood. CONCLUSION: The first exosome Phase I trial highlighted the feasibility of large scale exosome production and the safety of exosome administration.  相似文献   
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