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481.
Ravichandran G Premalatha S 《Indian journal of dermatology, venereology and leprology》1997,63(4):235-237
A case of pagetoid melanoma is reported for its unusual site, larger size and presence of suprabasal lacunae in the histopathological study. 相似文献
482.
Imprint cytology of the sentinel lymph node in the assessment of axillary node status in breast carcinoma. 总被引:3,自引:0,他引:3
D Ravichandran G Kocjan M Falzon R Y Ball D N L Ralphs 《European journal of surgical oncology》2004,30(3):238-242
BACKGROUND: Intra-operative assessment of the sentinel lymph node (SLN) status may allow the surgeon to complete the breast cancer surgery in most patients in one sitting. We have studied the role of imprint cytology in the assessment of SLN status. PATIENTS AND METHODS: Imprint cytology of the SLN in 132 patients with invasive breast carcinoma was correlated with the histopathological assessment of the SLN and overall axillary nodal status. In 26 patients, the cytology was reported intra-operatively. RESULTS: Imprint cytology reflected the status of the parent node well (sensitivity 86%, specificity 97%, positive predictive value (PPV) 92%, negative predictive value (NPV) 93%). Its ability to reflect the axillary status was also good (sensitivity 70%, specificity 97%, PPV 95% and NPV 83%) but somewhat diminished by the relatively high number of false-negative SLN in the study. Intra-operative assessment (sensitivity 86%, specificity 100%, PPV 100% and NPV 95%) did not reduce the accuracy of imprint cytology in predicting the SLN status and took a mean of 24.5 min. CONCLUSIONS: Imprint cytology is an accurate and relatively simple method for the assessment of the SLN and can be a useful intra-operative tool. 相似文献
483.
Yoke-Yeow Yap MD MMed Shahid Hassan MBBS DLO MCPS Melissa Chan BSc Pua Kin Choo MBBS MS Manickam Ravichandran BSc MSc PhD 《Otolaryngology--head and neck surgery》2007,136(6):986-991
OBJECTIVES: This study examines the presence of Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC) by using polymerase chain reaction (PCR). STUDY DESIGN: Eighty-six postnasal biopsy samples and 71 fine-needle aspirate samples of neck masses were obtained from patients who were clinically suspect for NPC. Genomic DNA was extracted from the samples, and EBNA1, EBNA2, and LMP genes of EBV were detected by PCR. PCR results were compared with NPC histopathology findings. RESULTS: The sensitivity of PCR to detect EBNA1 (97.14%), EBNA2 (88.57%), and LMP (91.43%) genes of EBV in nasopharyngeal biopsy samples were higher than those in fine-needle aspirate samples. CONCLUSION: Detection of EBV by PCR in tissue obtained from nasopharyngeal biopsy and fine-needle aspirate samples of neck masses is a relatively inexpensive, reliable, and accurate method of diagnosing NPC. Detection of EBV genes is on par with histopathological examination (HPE) and superior to fine-needle aspirate cytology. SIGNIFICANCE: PCR is an ideal tool for suggesting NPC and guiding the diagnostic workup in occult primary tumors, facilitating earlier diagnosis and reducing morbidity and mortality. 相似文献
484.
485.
486.
Emily J. Mellen David G. Harper Caitlin Ravichandran Eric Jensen Marisa Silveri Brent P. Forester 《The American journal of geriatric psychiatry》2019,27(8):783-793
ObjectiveThis study compared brain energy metabolism, as measured by cerebral concentrations of glutamate (Glu), glutamine (Gln), and N-acetyl aspartate (NAA), in older age bipolar depression (OABD) to that of psychiatrically healthy comparison subjects using proton (1H) magnetic resonance spectroscopy imaging at 4-Tesla. Metabolite levels were assessed in OABD subjects before and after 8 weeks of lamotrigine therapy with the goal of determining relationships between cerebral energy metabolism, depression symptom severity, and changes in depression symptom response.MethodsIndividuals (n = 21, mean age: 62.0 ± 5.9 years) with bipolar disorder, current episode depressed, and a healthy comparison group (n = 14, mean age: 67.5 ± 8.8 years) were selected. Participants with bipolar disorder, current episode depressed, were treated in open label fashion with lamotrigine monotherapy for 8 weeks. All subjects were scanned with 1H magnetic resonance spectroscopy at 4T at baseline and again after 8 weeks to assess levels of cerebral metabolites in the anterior cingulate cortex and parieto-occipital cortex. Metabolite levels were examined as ratios relative to creatine (Cr). Response to 8 weeks of lamotrigine treatment in the bipolar disorder, current episode depressed group, was assessed as a continuous measure on the Montgomery-Asberg Depression Rating Scale.ResultsNAA/Cr ratio in OABD was significantly lower by 14% (95% confidence interval: [1%, 26%]) than in comparison subjects at baseline. However, there were no associations between NAA/Cr, Glu/Cr, or Gln/Cr and either depression severity or lamotrigine treatment.ConclusionGroup differences in NAA suggest evidence for a deficit in cerebral energy metabolism in OABD. 相似文献
487.
Aspergillus peritonitis is a rare, potentially fatal complication of continuous ambulatory peritoneal dialysis (CAPD). We report a case of CAPD peritonitis caused by Aspergillus terreus in a 55-year-old female patient. 相似文献
488.
Rajasekaran S Jeyaseelan L Ravichandran N Gomathi C Thara F Chandrasekar C 《Journal of tropical pediatrics》2009,55(4):225-232
The objective of this article is to study the survival pattern and the prognostic factors for HIV-infected children on antiretroviral therapy (ART) for two and half years at the Government Hospital of Thoracic Medicine, Tambaram, Chennai, India. We studied 295 children who were initiated on ART from 1 April 2004 to 30 September 2006 at a large, public tertiary care facility in Chennai, India. Weight for age Z-score was calculated. Survival curves and Cox proportional hazard models were used to identify risk factors for mortality. The mean and median follow up was 11 and 10 months, respectively. The cumulative survival probability at 6, 12, 18, 24 and 30 months was 93, 90, 89.7, 89.7 and 89.7%, respectively. Of the children who died, about 50% died within the first month. Nearly 6% of the children had adherence less than 95%. The children who had a baseline CD4 percent less than or equal to 14% had significantly (p < 0.05) higher mortality as compared to children who had 20% or more. The children who had negative or no change in weight for age Z-score and hemoglobin had 18.9 (3.7-95.7) times significantly higher mortality as compared to children who had positive change in both variables (p < 0.001). The sensitivity, specificity and likelihood ratio of the positive test for negative change or no change in HB was 65%, 85% and 4.3, respectively. Similarly, these were 80%, 73% and 3% for negative or no change in Absolute Lymphocyte Count (ALC). These findings indicate the feasibility and effectiveness of implementing an ART program in a large government hospital in India. Simple nutritional variable hemoglobin and immunologic variable ALC could be used to monitor the progression of disease in children. 相似文献
489.
AIM: Since the skin dose becomes the limiting factor while deciding the tumorcidal dose, the detailed analysis of dose distribution in the build-up region is necessary for high-energy photon beams. In this study the beam characteristics affecting the build-up and skin dose for 6- and 18-MV photons are analyzed. MATERIALS AND METHODS: Measurements were made with 6- and 18-MV photons using a PTW parallel-plate ionization chamber (B 23344-036) and a RDM-1F electrometer. Build-up ionization measurements were made with the chamber fitted into a 25 x 25 x 25 cm polystyrene phantom with a fixed SSD of 100 cm. The entrance and build-up dose measurements were made with a polycarbonate and a mesh type metallic shielding tray and a 45 degrees wedge. Exit dose measurements were carried out for the graphite patient supporting assembly table top, 1.0 cm thick piece of wood and the 1.0 cm thick patient supporting perspex base frame for head and neck treatments. RESULTS: It was observed that the dmax decreased slightly with field size as with other accelerators. For both photon energies the surface dose was observed to increase with increase in field size. It was also noticed that the dose in the build-up region increases slightly when the polycarbonate secondary blocking tray is introduced with the increase in surface dose. The data show that the tray perturbation factor (TPF) at surface decreases steadily with tray-surface distance for both photon beams for all field sizes. It was noted that the TPF was more when the polycarbonate tray was introduced at shorter tray-surface distances for both energies. At tray-surface distances above 60 cm the TPF almost remained close to unity for 6-MV photons for all field sizes, whereas the continuous decrease in TPF could be noted for 18-MV photon beams even after the TPF reached unity. CONCLUSION: The increase in surface dose with field size for both photon energies is due to the electron scattering from the intervening materials. The use of wedge filters absorbs low-energy scattered electrons significantly and hence, the relative surface dose (RSD) is always less than unity. The increase in dose enhancement percentage with graphite compared to perspex supporting assembly indicates that the electron backscatter is proportional to the atomic number of the medium. 相似文献
490.
Yan SF Barile GR D'Agati V Du Yan S Ramasamy R Schmidt AM 《Current diabetes reports》2007,7(2):146-153
The interaction of glucose-modified and inflammation-promoting ligands with the receptor for advanced glycation end products
(RAGE) is emerging as a central mechanism contributing to the diverse complications of diabetes. These ligands, particularly
in oligomeric form, bind to RAGE and transduce intracellular signals. The consequences of this interaction, as elucidated
in cultured cells and animal models, include upregulation of inflammatory and tissue-degradative pathways. Pharmacologic antagonism
of RAGE may hold promise for the treatment of diabetic complications. 相似文献