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1.
Three-dimensional (3D) reconstruction in routine computerized tomography (CT) presupposes that the referring clinicians are motivated, software programs are of good quality, a second working console is available and manipulations are made by experienced persons. Maxillofacial surgery is the main, conventional indication, but the method is also used to plan the surgical treatment of craniofacial malformations and that of injuries and tumours. 3D reconstruction cannot replace a thorough analysis of the acquisition sections since its spatial definition is not as good as theirs. Without competing with pure research-work, a number of applications remain in the realm of speculative imaging, but it cannot be denied that 3D reconstruction has an interesting potential for teaching.  相似文献   
2.
A new catheter was used in an attempt to re-establish coronary flow in six patients with acute occlusion after angioplasty and prior to emergency coronary artery bypass surgery. All patients suffered from severe chest pain, and the electrocardiogram showed signs of acute transmural ischemia. A reperfusion catheter manufactured by Advanced Cardiovascular Systems (ACS) has 36 side holes spirally arranged along the distal 10 cm. It is introduced over an exchange wire. After the catheter was positioned across the occlusion, five patients had complete relief of chest pain, and another patient had partial relief. The electrocardiogram normalized in all six patients (in one only initially). Two patients developed a limited myocardial infarction, but four did not. The time between introduction of the reperfusion catheter and aorta cross clamping varied between 1.5 and 6.5 hours, and there were no complications related to its use. We conclude that the ACS reperfusion catheter is useful in re-establishing coronary blood flow after failed angioplasty and prior to emergency coronary artery bypass surgery.  相似文献   
3.
Immunocytochemical assays were performed on cell cultures as well as on a wide range of human tissues using a monoclonal antibody, MAb 83D4, produced by a murine hybridoma generated by immunization with a cell suspension from a paraffin block of human breast carcinoma tissue. Frozen breast tissue samples (n = 49) were compared to fixed and paraffin-embedded samples (n = 62). Paraffin sections (n = 194) from a variety of human tissues were compared to breast immunoreactivity. Immunoprecipitates, resulting from positive reactions between 83D4 and Avidin Biotin Peroxidase, were evaluated by computer-assisted microcytophotometry (SAMBA). In some frozen breast samples (n = 27), 83D4 antigen distribution was correlated with tumor cell DNA index, ploidy balance, growth fraction (Ki67), hormone receptor (ER, PR) antigenic sites, NORsAg and oncoprotein pHER-2/neu cell content. MAb 83D4 reacted with 3 breast cancer cells lines (MCF7, T47D and H466B) but not with normal epithelial breast cells in culture. The immunostaining in frozen paraffin sections from breast were similar. Like most normal tissues, normal breast did not react with 83D4. Cellular MAb 83D4 antigen concentration increases with the degree of malignancy but is independent of DNA nuclear content, ER, PR, growth fraction and pHER-2neu in cancers. These results suggested that routine immunohistochemical procedures using MAb 83D4 could facilitate the grading of breast cancer, in particular by allowing detection of microvascular invasions in the breast as well as at a distance and of blood-born micrometastases, especially in bone marrow.  相似文献   
4.
Progesterone exerts on the central nervous system a number of effects, some of which are estrogen dependent mostly in the preoptic area and the mediobasal hypothalamus. In these regions, an immunocytochemical study was used to evaluate differences in progesterone receptor (PR) immunoreactivity between the male and the female guinea pig in response to 10 μg/day estradiol benzoate (EB) for 5 consecutive days. Compared to EB-treated females, EB-treated males showed a slightly lower number of PR-immunoreactive cells in the preoptic area whereas PR-immunoreactivity appeared in more cells in the anterior part of the ventrolateral nucleus. The numbers of PR-immunoreactive cells in the arcuate nucleus did not differ significantly between males and females. These results show that regionally localized sex differences exist in the induced PR system after 5 days exposure to EB.  相似文献   
5.
The biological activity carried by the carboxy-terminal domain of SV40 large T antigen has been investigated by isolating mutants deleted for a stretch of six acidic residues which by analogy with polyoma middle T antigen might be essential for the activity of the protein. We have constructed an "in-phase" deletion of 37 residues that includes the complete acid residues cluster. In order to parallel the polyoma hr-t mutants genotype, the deletion was introduced in virus strains either competent or defective for the small t antigen. We conclude from these experiments that the deletion of this unusual sequence does not affect per se any of the known biological properties of the virus.  相似文献   
6.
To determine the extent to which the vagina, endocervix, and amniotic fluid screen the Escherichia coli strains responsible for neonatal infections, we studied the genetic relationships among 105 E. coli strains isolated from all of the ecosystems involved in this infectious process. Twenty-four strains were isolated from the intestinal flora, and 25 strains were isolated from the vaginas of pregnant women. Twenty-seven strains were isolated from the amniotic fluid, blood, and cerebrospinal fluid (CSF) of infected neonates. The intraspecies genetic characteristics of all of the isolates were determined by random amplified polymorphic DNA (RAPD) analysis, PCR ECOR (E. coli reference) grouping, and PCR virulence genotyping. A correlation was found between the intraspecies distributions of the strains in the A, B1, B2, and D ECOR groups and in the two major RAPD groups (I and II). Nevertheless, the distribution of the E. coli strains in the RAPD groups according to their anatomical origins was more significant than their distribution in the ECOR groups. This may be explained by the existence of an E. coli subpopulation, defined by the RAPD I group, within the ECOR B2 group. This RAPD I group presents a major risk for neonates: 75% of the strains isolated from patients with meningitis and 100% of the strains isolated from patients with bacteremia were in this group. The vagina and the amniotic fluid are two barriers that favor colonization by highly infectious strains. Indeed, only 17% of fecal strains belonged to the RAPD I group, whereas 52% of vaginal strains and 67% of amniotic fluid strains belonged to this subpopulation. The ibeA and iucC genes were significantly associated with CSF strains, whereas the hly and sfa/foc genes were more frequent in blood strains. These findings could serve as a basis for developing tools to recognize vaginal strains, which present a high risk for neonates, for use in prophylaxis programs.  相似文献   
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8.
The antibody response of rabbits immunized with a total histone mixture containing randomly coiled H1/H5, H2A, H2B, H3 and H4 devoid of DNA was investigated in direct and competitive ELISA. The antisera were tested with isolated histones and chromatin and with a series of overlapping synthetic peptides covering the entire sequences of the four core histones and two peptides of H1. It was found that the New Zealand (NZ) white rabbits immunized with the total histone (TH) mixture complexed with RNA produced IgG antibodies reacting with histones and with a number of histone peptides but not with chromatin. The antisera also contained IgG antibodies which bound components that correspond to common target antigens in autoimmune diseases such as native dsDNA, peptides of Sm-D antigen, ubiquitin, branched peptides of ubiquitinated H2A and poly(ADP-ribose). By competition experiments, it was shown that these antibodies corresponded to non-crossreacting antibody populations. New Zealand rabbits immunized with TH in the absence of RNA or random outbred rabbits immunized with the RNA-complexed histone fraction produced antibodies reacting with histone, chromatin and very few histone peptides, while no activity with non-related antigens was observed. The pattern of reactivity of antisera raised in NZ rabbits with RNA-complexed TH was found to be very similar to that observed in sera of patients with systemic lupus erythematosus while, in contrast, the antibody response was very different in NZ or outbred rabbits immunized with various native nuclear particles and with individual histones. Altered nucleosome particles rather than native nucleosomes may represent the antigenic stimulus giving rise to autoantibodies.  相似文献   
9.
Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients.  相似文献   
10.
BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA.  相似文献   
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