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排序方式: 共有593条查询结果,搜索用时 15 毫秒
91.
F J Leinweber A J Szuna T H Williams G J Sasso B A DeBarbieri 《Drug metabolism and disposition》1981,9(3):284-291
The disposition of radioactive (-)-3-phenoxy-N-methyl[2-3H]morphinan in dogs after oral administration has been investigated. Unchanged drug was not found in bile, urine, or feces. Excretion of total radioactivity in feces ranged from 67 to 78% of an oral dose. Two unconjugated metabolites were isolated from feces and identified by NMR and GC/MS. Both were substituted on the phenoxy group; they were found to be the p-hydroxy (pOH-PMM) and the m-methoxy-p-hydroxy (mOCH3-pOH-PMM) metabolites. Further, levorphanol and norlevorphanol were identified in feces both as free and conjugated metabolites, as well as a small amount of levomethorphan. Urine contained mostly unknown metabolites and conjugated levorphanol and pOH-PMM. Although the glucuronide of mOCH3-pOH-PMM was the major metabolite in bile, smaller amounts of the glucuronide and sulfate conjugated of both levorphanol and pOH-PMM were also found. Estimates for the total urinary and fecal excretion (as percentages of the dose) by two dogs for the five known metabolites were as follows: levorphanol, 18.8-21.5%; pOH-PMM, 14.4-20.6%; mOCH3-pOH-PMM, 14.9%; norlevorphanol, 2.8-6.1%; levomethorphan, 0.5%. Two of these metabolites, pOH-PMM and levorphanol, are potent analgesics. 相似文献
92.
True and pseudo-cysts of the pancreas are described and their aetiology, pathology, laboratory tests, radiological examination, differential diagnosis, symptomatology and surgical management are illustrated. A series of 22 cases of pancreatic cyst is presented. Surgical management consisted of 14 cystogastrostomies, 3 cystoduodenostomies, 2 resections of the tail of the pancreas, 1 internal drainage between the fistular segment of the gland and the gastric cavity, and 2 external drainages with a Pezzer tube. It is felt that internal drainage is the operation of choice. Of the surgical techniques available, a preference is expressed for cystogastrostomy and cystoduodenostomy. 相似文献
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Current treatments of primary sclerosing cholangitis 总被引:4,自引:0,他引:4
Vacca M Krawczyk M Petruzzelli M Sasso RC van Erpecum KJ Palasciano G van Berge-Henegouwen GP Moschetta A Portincasa P 《Current medicinal chemistry》2007,14(19):2081-2094
Primary Sclerosing Cholangitis (PSC) is a chronic cholestatic disease characterized by hepatic inflammation and obliterative fibrosis, resulting in both intra- and extra-hepatic bile duct strictures. End-stage liver disease and bile duct carcinoma represent frequent complications. Incidence and prevalence of PSC in USA have been recently estimated as 0.9 per 100,000 person-years, and 1-6 per 100,000 person-years, respectively. Major diagnostic criteria include the presence of multifocal strictures, beadings of bile ducts, and compatible biochemical profile, once excluded secondary causes of cholangitis. Since the aetiology of PSC remains poorly defined, medical therapy is currently limited to symptom improvement and prolonged survival. Ursodeoxycholic acid (UDCA), corticosteroids and immunosuppressants have been proposed alone or in combination to improve the clinical outcome. In selected cases, surgical or endoscopic procedures need to be considered. Orthotopic liver transplantation (OLT) is at the moment the only definitive approach although disease relapse has been reported. In this article the state of the art in PSC treatment and future promises in this field are reviewed. 相似文献
96.
Bacterial vaginosis (BV) is the most frequent diagnosis made in women with lower genital tract symptoms. It has recently been observed that 90 % of subjects with BV show the growth of bacteria in the form of biofilms as against only 10% without BV, and that Gardnerella vaginalis was the predominant species. The propensity of G. vaginalis to form biofilm is clinically relevant because this form of growth allows it to tolerate higher concentrations of certain antibiotics, thus increasing the possibilty of recurrent BV even after apparently curative therapy. The aim of this study was to investigate whether thymol (CAS 89-83-8), a molecule present in thyme essential oil, that is credited with having a series of pharmacological properties including antimicrobial and antifungal effects, can interfere with newly formed and mature G. vaginalis biofilms. The ability of G. vaginalis ATCC 49145 and two G. vaginalis strains isolated from human BV to form biofilm in flat-bottomed 96-well microtitre plates was verified, and the effects of thymol concentrations ranging from 1 to 1/16 MIC (minimum inhibitory concentration) on preformed and mature biofilms was investigated by means of spectrophotometric analysis, Nomarski interference contrast microscopy, and fluorescence microscopy with live-dead cell visualisation (SYTO 9 and propidium iodide). Native biofilm was inhibited by concentrations ranging from 1 MIC to 1/8 MIC (32.77% +/- 2.37 to 11.39% +/- 1.46), and mature biofilm was inhibited by concentrations ranging from 1 MIC to 1/4 MIC (26.18% +/- 1.36 to 13.20% +/- 1.44). Nomarski interference contrast and fluorescence microscopy visually confirmed these findings. As biofilm is a multi-factorial phenomenon, the multiple mechanisms of thymol may act on different steps in the evolution of mature biofilm. 相似文献
97.
BACKGROUND: The impact of depression on the workplace has been widely observed in studies examining absenteeism and reduced productivity during days at work. However, there is little scientific evidence about whether depression interventions are cost-beneficial to employers. OBJECTIVE: We construct a cost-benefit analysis of depression treatment under different workplace assumptions better reflecting the nature of employment. RESEARCH DESIGN: Data from a randomized controlled trial in which employed primary care patients with depression were treated in practices randomly assigned to an enhanced treatment intervention or usual care were used to construct a cost-benefit model from an employer perspective under different assumptions regarding employment. SUBJECTS: A national sample of 198 workers employed in a range of positions by companies was studied. MEASURES: Benefits included self-reported productivity and absenteeism; costs included intervention and treatment costs. Net benefit was calculated under different scenarios and return on investment (ROI) is derived. RESULTS: Enhanced depression treatment resulted in an average net benefit to the employer of Dollars 30 per participating worker in Year 1 of the intervention and Dollars 257 per participating worker in Year 2, for an estimated ROI during the 2-year period of 302%. ROI increased in firms that rely on team production, hire more costly substitute labor, or realize penalties for output shortfalls. ROI decreased in firms that have a large fraction of employees with dependent coverage and experience high turnover rates. Results also are sensitive to how subjectively reported productivity is valued. CONCLUSION: Many employers will receive a potentially significant ROI from depression treatment models that improve absenteeism and productivity at work. 相似文献
98.
Ilaria Plantamura Patrizia Casalini Erica Dugnani Marianna Sasso Elvira D'Ippolito Monica Tortoreto Matilde Cacciatore Carla Guarnotta Cristina Ghirelli Isabella Barajon Francesca Bianchi Tiziana Triulzi Roberto Agresti Andrea Balsari Manuela Campiglio Claudio Tripodo Marilena V. Iorio Elda Tagliabue 《Molecular oncology》2014,8(5):968-981
Triple negative breast cancer (TNBC) is a very aggressive subgroup of breast carcinoma, still lacking specific markers for an effective targeted therapy and with a poorer prognosis compared to other breast cancer subtypes.In this study we investigated the possibility that TNBC cells contribute to the establishment of tumor vascular network by the process known as vasculogenic mimicry, through endothelial cell differentiation.Vascular‐like functional properties of breast cancer cell lines were investigated in vitro by tube formation assay and in vivo by confocal microscopy, immunofluorescence or immunohistochemistry on frozen tumor sections. TNBCs express endothelial markers and acquire the ability to form vascular‐like channels in vitro and in vivo, both in xenograft models and in human specimens, generating blood lacunae surrounded by tumor cells. Notably this feature is significantly associated with reduced disease free survival. The impairment of the main pathways involved in vessel formation, by treatment with inhibitors (i.e. Sunitinib and Bevacizumab) or by siRNA‐mediating silencing, allowed the identification of PDGFRβ and FGFR2 as relevant players in this phenomenon. Inhibition of these tyrosine kinase receptors negatively affects vascular lacunae formation and significantly inhibits TNBC growth in vivo.In summary, we demonstrated that TNBCs have the ability to form vascular‐like channels in vitro and to generate blood lacunae lined by tumor cells in vivo. Moreover, this feature is associated with poor outcome, probably contributing to the aggressiveness of this breast cancer subgroup. Finally, PDGFRβ and FGFR2‐mediated pathways, identified as relevant in mediating this characteristic, potentially represent valid targets for a specific therapy of this breast cancer subgroup. 相似文献
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