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31.
A 33-year-old woman with a 2-year history of swelling and pain in her buttock and left thigh fluctuating with her menstrual cycle who was becoming progressively disabled was referred to the department of orthopedics. Magnetic resonance imaging (MRI) detected a left buttock lesion of 3 × 2 cm that was initially diagnosed as muscular-fiber laceration with associated hematoma. The worsening of her symptomatology required an ultrasound-guided biopsy of the lesion that revealed endometriosis. Laparoscopy showed the pelvis to be free of gross disease. Hormonal suppression by means of gonadotropin-releasing hormone analog therapy proved adequate in temporarily alleviating symptoms. A year later the patient underwent surgical excision of the buttock lesion, which was effective in alleviating her symptoms for a short period of 10 months. A 1-year follow-up MRI revealed several small endometriotic foci, located among piriformis and obturator internus muscle fibers, which were considered not suitable for surgical removal. The patient is currently on a drug regime for pain management. However, she has experienced permanent muscular damage on her left buttock including significant omolateral gluteus strength reduction, functional impairment (inability to rotate laterally or bend her left leg), and the assumption of an antalgic gait while walking. Because of impairment in her deambulation capability, total physical invalidity was agreed for her by the National Health Care Services.  相似文献   
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In absence of a COVID-19 vaccine, testing, contact tracing and social restrictions are among the most powerful strategies adopted around the world to slow down the spread of the pandemic. Citizens of most countries are suffering major physical, psychological and economic distress. At this stage, a safe and effective COVID-19 vaccine is the most sustainable option to manage the current pandemic. However, vaccine hesitancy by even a small subset of the population can undermine the success of this strategy.The objective of this research is to investigate the vaccine characteristics that matter the most to Australian citizens and to explore the potential uptake of a COVID-19 vaccine in Australia. Through a stated preference experiment, preferences towards a COVID-19 vaccine of 2136 residents of the Australian states and territories were collected and analysed via a latent class model.Results show that preferences for mild adverse cases, mode of administration, location of administration, price and effectiveness are heterogeneous. Conversely, preferences for immediacy and severe reactions are homogeneous, with respondents preferring a shorter period until vaccine is available and lower instances of severe side effects. The expected uptake of the vaccine is estimated under three different scenarios, with the value of 86% obtained for an average scenario. By calculating individual preferences, the willingness to pay is estimated for immediacy, effectiveness, mild and severe side effects.  相似文献   
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Nine toxigenic and six non-toxigenic strains of Clostridium difficile, of varying virulence in the hamster model of antibiotic-associated colitis, were examined for the presence of a capsule. Antibody stabilisation of the capsule with heterologous and/or homologous antiserum fixed in glutaraldehyde, or direct fixation in glutaraldehyde/diamine, were used with added ruthenium red to stain the capsular glycocalyx. All strains possessed a capsule which was either loose-knit or compact, sometimes with attached globular masses. Better capsule preservation was achieved in some strains with glutaraldehyde/diamine/ruthenium red fixative than with homologous or heterologous antibody stabilisation. The possession of a capsule following in vitro growth does not appear to correlate with the virulence status of these strains of C. difficile.  相似文献   
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The role of oxygen limitation in protecting Pseudomonas aeruginosa strains growing in biofilms from killing by antibiotics was investigated in vitro. Bacteria in mature (48-h-old) colony biofilms were poorly killed when they were exposed to tobramycin, ciprofloxacin, carbenicillin, ceftazidime, chloramphenicol, or tetracycline for 12 h. It was shown with oxygen microelectrodes that these biofilms contain large anoxic regions. Oxygen penetrated about 50 microm into the biofilms, which averaged 210 microm thick. The region of active protein synthesis was visualized by using an inducible green fluorescent protein. This zone was also limited to a narrow band, approximately 30 microm wide, adjacent to the air interface of the biofilm. The bacteria in mature biofilms exhibited a specific growth rate of only 0.02 h(-1). These results show that 48-h-old colony biofilms are physiologically heterogeneous and that most of the cells in the biofilm occupy an oxygen-limited, stationary-phase state. In contrast, bacteria in 4-h-old colony biofilms were still growing, active, and susceptible to antibiotics when they were challenged in air. When 4-h-old colony biofilms were challenged under anaerobic conditions, the level of killing by antibiotics was reduced compared to that for the controls grown aerobically. Oxygen limitation could explain 70% or more of the protection afforded to 48-h-old colony biofilms for all antibiotics tested. Nitrate amendment stimulated the growth of untreated control P. aeruginosa isolates grown under anaerobic conditions but decreased the susceptibilities of the organisms to antibiotics. Local oxygen limitation and the presence of nitrate may contribute to the reduced susceptibilities of P. aeruginosa biofilms causing infections in vivo.  相似文献   
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Chuvash polycythemia (MIM 263400) is an autosomal recessive disorder characterized by a high hemoglobin level, relatively high serum erythropoietin, and early death. It results from a Von Hippel-Lindau (VHL) gene mutation (C598T) that causes increased HIF-1alpha activity and erythrocyte production in the face of normoxia. This polycythemia is endemic in Chuvashia, whereas its worldwide frequency is very low. We investigated the incidence of the Chuvash-type VHL mutation in Campania (South Italy) and identified 14 affected subjects (5 families). Twelve live on the island of Ischia (Bay of Naples). From analysis of the mutated allele, we found that the disease was more frequent on Ischia (0.070) than in Chuvashia (0.057). The haplotype of all patients matched that identified in the Chuvash cluster, thereby supporting the single-founder hypothesis. We also found that nonaffected heterozygotes had increased HIF-1alpha activity, which might confer a biochemical advantage for mutation maintenance. In conclusion, we have identified the first large cluster of Chuvash erythrocytosis outside Chuvashia, which suggests that this familial polycythemia might be endemic in other regions of the world.  相似文献   
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The pathogenesis of the decline of CD4 lymphocyte counts accompanying the typical course of HIV-1 infection is not completely defined and might be related to a differential susceptibility of naive and memory cells to HIV-1 exposure. Here, we examined the effects induced by heat-inactivated HIV-1 virions on these lymphocyte populations. Exposure of CD45RA naive T cells to inactivated viral particles induced a marked decrease of both mitogenic responses and activation-induced apoptosis. Conversely, the growth of CD45RO cells was less severely restrained. Analysis of intracellular levels of cell cycle regulatory proteins revealed an arrest at the G1/S restriction point of the naive but not memory subset. This effect was associated with alterations in phosphotyrosine profile and with a marked decrease of ERK and NJK kinase activation. Finally, up-regulation of the cAMP-dependent protein kinase A (PKA) activity induced by mitogens was not affected by virus. Altogether, these findings show that interaction of HIV-1 with the T cell surface is sufficient to inhibit the proliferative response of the CD4CD45RA subset by disturbing proximal TCR signaling. This mechanism would affect renewal of naive lymphocytes, contributing in such a way to the impairment of T cell turnover during the course of HIV-1 infection.  相似文献   
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Development of human neuroblastoma is due to an arrest in the differentiation program of neural crest sympathoadrenal progenitor cells. However, neuroblastomas, as well as their derived cell lines, maintain the potentiality of terminal differentiation. We investigated the molecular mechanisms by which retinoic acid, a molecule introduced in clinical trials for chemotherapy, induces differentiation in neuroblastoma cell lines. Our findings demonstrate that the retinoic acid-dependent growth arrest of LAN-5 neuroblastoma cell line is associated to a very large accumulation (>tenfold) of p27Kip1 protein, a cyclin-dependent kinase inhibitor; the protein binds and inhibits cyclin-dependent kinase 2, 4 and 6 activities, thus hampering pRb and p107 phosphorylation. p27Kip1 build-up was observable as an early phenomenon (12 - 24 h) after retinoic exposure and resulted in a time-dependent accumulation of high quantities of a free p27Kip1 form. Furthermore, retinoic treatment causes an increase of cyclin-dependent kinase 5 level and activity; however, immunoprecipitation studies proved the absence of interaction with p27kip1. No noticeable variation of other components of G1 phase cell cycle engine was observed. Pulse-chase experiments showed a remarkable elongation of p27Kip1 half-life in retinoic-treated LAN-5, while no enhancement of p27Kip1 gene expression and of the translational efficiency of its messenger RNA were demonstrated. In vivo degradation of p27Kip1 was sensitive to two highly specific proteasome inhibitors, LLnL and lactacystin, while the calpain inhibitor II ALLM and the cysteine protease inhibitor E64 did not modify the level of the protein. LLnL treatment caused a very rapid (2 h) build-up of the Cdk inhibitor content and the accumulation of higher molecular weight anti-p27Kip1 immunoreactive bands, which probably represent ubiquitinated forms of the protein. Finally, in vitro experiments demonstrated that extracts prepared from retinoic-treated LAN-5 cells degraded recombinant p27Kip1 at a rate remarkably slower than the untreated cells. Our results indicate that retinoic acid strongly increases p27Kip1 levels by down-regulating the ubiquitin-proteasome p27Kip1 degrading pathway.  相似文献   
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