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41.
The study outlines the evaluation of an intellectual disability screening tool, the Child and Adolescent Intellectual Disability Screening Questionnaire (CAIDS-Q), with two age groups. A number of aspects of the reliability and validity of the CAIDS-Q were assessed for these two groups, including inter-rater reliability, convergent and discriminative validity. For both age groups, a significant positive relationship was found between full scale IQ and CAIDS-Q score, indicating convergent validity. Significant differences were found in the CAIDS-Q scores between those with and without an intellectual disability, with the former group scoring significantly lower. The sensitivity and specificity of the CAIDS-Q were above 96.7% and 85.5% respectively for the younger group and 90.9% and 94.9% respectively for the older group. Limitations and implications of the study are discussed.  相似文献   
42.
Considerable positive experience in functional radiosurgery has been reported since Leksell??s first experience in 1951, but the development of frameless radiosurgery was been limited because of the difficulty of identifying invisible functional targets. In this paper we report on two cases of bilateral parkinsonian tremor successfully treated with DBS on one side and with frameless radiosurgery on the contralateral side. We focus on the methodology developed to define the three-dimensional target coordinates for frameless radiosurgery. Two patients suffering from a disabling upper-limb parkinsonian tremor underwent frameless radiosurgical thalamotomy. To accurately identify the treatment target the CT gantry was treated as a stereotactic frame; a rototranslation between the origin of the screen and the origin of the stereotactic atlas allowed us to obtain atlas-registered 3D coordinates of each point on the CT axial brain slices. Both patients achieved complete bilateral tremor control by unilateral radiosurgery and contralateral DBS. We developed a method for determining the 3D coordinates of a known functional target to treat with frameless radiosurgery. Based on the initial experiences, frameless radiosurgery appears to be an alternative treatment for Parkinsonian upper limb tremor in the presence of increased surgical risks for DBS placement.  相似文献   
43.
Summary BK virus (BKV)-transformed cells and BKV-induced tumors as well asin vitro derived tumor cell lines were all found to contain BKV DNA sequences when analysed by DNA-DNA reassociation kinetics. In transformed cells the number of viral genome equivalents per diploid cell genome (VG/CG) decreased with increasing generations. Likewise, single cell clones had a lower VG/CG than parental transformed cells. BKV-induced tumors had a high VG/CG. Tumor cells cultivatedin vitro and their clones had a lower VG/CG than BKV-induced tumors from which they were derived, suggesting a multiclonal origin of tumors. Hamster tumors induced by subcutaneous inoculation of BKV-transformed cells or tumor cell lines had a higher VG/CG than cells producing them. Variation in VG/CG is discussed in terms of cell selection depending on differentin vitro orin vivo conditions of cell growth. In some cases, however, the decrease in VG/CG most likely depends on loss of free viral sequences from transformed cells or tumors.With 2 Figures  相似文献   
44.
Previously we found that the availability of ShcA adapter is maximal in neural stem cells but that it is absent in mature neurons. Here we report that ShcC, unlike ShcA, is not present in neural stem/progenitor cells, but is expressed after cessation of their division and becomes selectively enriched in mature neurons. Analyses of its activity in differentiating neural stem/progenitor cells revealed that ShcC positively affects their viability and neuronal maturation via recruitment of the PI3K-Akt-Bad pathway and persistent activation of the MAPK pathway. We suggest that the switch from ShcA to ShcC modifies the responsiveness of neural stem/progenitor cells to extracellular stimuli, generating proliferation (with ShcA) or survival/differentiation (with ShcC).  相似文献   
45.
Secondary mouse and hamster cells were transformed with BK virus (BKV) or with purified BKV DNA. Restriction analysis of viral sequences present in transformed cell lines yielded complex patterns, indicating the presence in most lines of more than one viral intergration/cell and the existence of a large number of available integration sites. In spite of this variability, however, the arrangement of integrated viral sequences had specific features in the two types of transformed cells. Tandem insertions of full-size BKV genomes, which were a constant feature of transformed mouse lines, were not found in hamster lines. These appeared to contain no complete, intact BKV genomes, but only genomes interrupted by the insertion event or tandem integrations of incomplete viral sequences. Traces of free, full-size viral DNA were observed in all transformed mouse lines, but not in hamster lines. One transformed hamster line, after 84 passages in culture, showed the presence of tandemly integrated, full-size BKV DNA, which was not found in cells at 14 passages after the appearance of the transformed phenotype. This was the only BKV transformed line from which virus could be rescued by fusion with permissive cells. These results suggest that BKV DNA integration occurs differently in hamster (nonpermissive) and mouse (semipermissive) cells, and support the idea that excision of integrated viral DNA occurs usually via homologous recombination.  相似文献   
46.
Fifty-seven heart specimens with complete transposition (concordant atrioventricular and discordant ventriculo-arterial connections) and ventricular septal defect were reviewed to establish the spectrum of morphology of the ventricular septal deficiency and to correlate the type of defect with presence of subarterial and aortic arch obstruction. The ventricular septal defect was single in 52 cases (27 perimembranous and 25 muscular) and multiple in five. A normal alignment between the outlet component and the rest of the muscular septum was present in 18 cases (10 perimembranous, five muscular, and three multiple). The defect was the consequence of septal malalignment in the other 39 specimens; 29 with rightward and 10 with leftward displacement of the outlet septum. Rightward displacement led to perimembranous defects in 16 cases and muscular defects in 12. In another instance, a perimembranous malalignment defect was associated with a muscular inlet defect. Subaortic stenosis due to either deviation of the outlet septum or prominence of the ventriculo-infundibular fold and septoparietal trabeculations was observed in 14 cases. Leftward displacement of the outlet septum was associated with one perimembranous and eight muscular defects and with multiple (muscular outlet plus muscular inlet) defects in another case. Of these, five cases showed subpulmonary stenosis. Aortic arch obstructions were present in 19 cases; 14 showed rightward malalignment of the outlet septum, which produced subaortic stenosis. These findings suggest two things: Unlike the situation in hearts with "normally related" great arteries, most defects in complete transposition result from malalignment of the outlet septum, with many being of the muscular type. Rightward or leftward displacement of the outlet septum frequently results in subaortic or subpulmonary stenosis, respectively. Aortic arch obstructions, although frequent, are not always associated with subaortic stenosis.  相似文献   
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