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Paolo Consigliere Arunava Ray Caroline Witney-Lagen Alessio Bernasconi Laura Mariani Luigi Piscitelli Luis Natera Berta Buch Ehud Atoun Giuseppe Sforza Ofer Levy 《Seminars in Arthroplasty》2022,32(1):174-183
BackgroundReverse total shoulder arthroplasty (rTSA) improves shoulder elevation in patients treated for cuff tear arthropathy (CTA) or irreparable massive cuff tears. Patient satisfaction can be limited by reduced active external rotation (AER). Rotator cuff muscles that externally rotate the shoulder are infraspinatus and teres minor (TM).AimThe purpose of this study was to assess the correlation between preoperative TM fatty degeneration and postoperative AER after rTSA performed for CTA or irreparable cuff tears.MethodsConstant scores and active range of motion were consecutively collected for 109 shoulders in 97 patients (mean: 75.73 ± 8.94 years; 31 male, 66 female) over a 10-year period. AER was evaluated with the humerus in adduction (AER1) and in abduction. TM muscle atrophy was scored according to Goutallier's classification, assessed on preoperative computed tomography scans.ResultsMultivariate analysis showed that TM fatty infiltration was a predictor of AER1. AER1 decreased by 4.9 degrees preoperatively and by 6.4 degrees at the final follow-up, for each increment in Goutallier grade (P = .02). Postoperatively, AER evaluated with humerus in abduction improved significantly (P < .001), but did not correlate with TM Goutallier grade. At a mean follow-up of 38 months (range: 24 to 96), mean Constant score improved from 20.5 ± 11.1 to 68.4 ± 14.9 (P < .001), as did shoulder active range of motion in all planes including AER1 (P < .001).ConclusionThis is the first study to quantify the inverse correlation between AER and TM Goutallier grade, both preoperatively and after rTSA; this information guides prognosis for patients with TM degeneration undergoing rTSA. Further studies are necessary to have a better understanding and find reliable solutions.Level of evidenceLevel III; Case Series 相似文献
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Computational models of MRI characteristics of focal cortical dysplasia improve lesion detection 总被引:3,自引:0,他引:3
Antel SB Bernasconi A Bernasconi N Collins DL Kearney RE Shinghal R Arnold DL 《NeuroImage》2002,17(4):1755-1760
In many patients, focal cortical dysplasia (FCD) is characterized by minor structural changes that may go unrecognized by standard radiological analysis. We previously demonstrated that visual analysis of a composite map based on three simple models of MRI features of FCD increased the sensitivity of FCD lesion detection, compared to visual analysis of conventional MRI. Here we report on the use of improved methods for characterizing FCD which improve contrast in the composite maps: a Laplacian-based metric for measuring cortical thickness, a convolutional kernel to model blurring of the GM-WM interface, and an operator to measure hyperintense T1 signal. To validate these methods, we processed the MRIs of 14 FCD patients with our original set of image processing operators and an improved set of image processing operators. Comparison of the composite maps associated with the two sets of operators revealed that contrast between lesional tissue and nonlesional cortex was significantly increased in the composite maps associated with the set of improved operators. Increasing this contrast is an important step toward the goal of automated FCD lesion detection. 相似文献
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The effectiveness and tolerability of epoetin alfa in patients with multiple myeloma refractory to chemotherapy 总被引:5,自引:0,他引:5
F. Dammacco F. Silvestris G. L. Castoldi B. Grassi C. Bernasconi G. Nadali G. Perona A. De Laurenzi U. Torelli E. Ascari P. L. Rossi Ferrini F. Caligaris-Cappio A. Pileri L. Resegotti 《International Journal of Clinical & Laboratory Research》1998,28(2):127-134
Anemia is a frequent complication of multiple myeloma, becoming chronic in patients who are resistant to chemotherapy. This
randomized, parallel, controlled multicenter study (71 patients receiving concomitant chemotherapy) evaluated the efficacy
and safety of epoetin alfa in improving anemia and eliminating the need for transfusions in multiple myeloma patients refractory
to conventional first- or second-line chemotherapy. Forty patients were treated with subcutaneous epoetin alfa (150 IU/kg
per dose, increasing to 300 IU/kg per dose, every 3 weeks) for 6 months, and 31 entered a control group. The epoetin alfa
group had a significantly (P≤0.001) greater percentage of patients (75% vs. 21%) with increases in hemoglobin levels and/or reduced transfusion requirements.
In 44 non pre-transfused patients (20 controls, 24 in the epoetin alfa group), the mean increase in hemoglobin was significantly
(P≤0.0001) greater in the epoetin alfa group (+2.1 vs. −0.2 g/dl). Increases in hematocrit and red blood cells were also significantly
(P≤0.0001) greater in epoetin alfa-treated patients, with corresponding reductions in transfusion requirement. In the 27 pre-transfused
patients (11 controls, 16 in the epoetin alfa group), there was a trend towards reduced transfusional need in epoetin alfa-treated
patients. Thus, in patients with multiple myeloma refractory to chemotherapy epoetin alfa is a well-tolerated treatment which
improves anemia in non pre-transfused patients and appears to reduce transfusion need in those previously transfused. 相似文献
6.
Mechanism of metronidazole resistance in Helicobacter pylori: comparison of the rdxA gene sequences in 30 strains 总被引:5,自引:0,他引:5 下载免费PDF全文
The rdxA gene of 30 independently isolated Helicobacter pylori strains was sequenced. A comparison of the rdxA sequences revealed a higher percentage of amino acid substitutions in the corresponding protein than in other housekeeping genes. Out of 122 point mutations, 41 were missense and 4 were nonsense. A resistant strain with a nucleotide insertion in the rdxA sequence was also found. With the exception of the point mutations and the insertion generating a stop signal, no particular nucleotide mutation or amino acid substitution could be associated to metronidazole resistance. Moreover, phylogenetic analysis of the 30 nucleotide sequences did not demonstrate specific clusters associated with the resistance phenotype. 相似文献
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Wolbers M Battegay M Hirschel B Furrer H Cavassini M Hasse B Vernazza PL Bernasconi E Kaufmann G Bucher HC;Swiss HIV Cohort Study 《Antiviral therapy》2007,12(6):889-897
BACKGROUND: CD4+ T-cell recovery in patients with continuous suppression of plasma HIV-1 viral load (VL) is highly variable. This study aimed to identify predictive factors for long-term CD4+ T-cell increase in treatment-naive patients starting combination antiretroviral therapy (cART). METHODS: Treatment-naive patients in the Swiss HIV Cohort Study reaching two VL measurements <50 copies/ml >3 months apart during the 1st year of cART were included (n=1816 patients). We studied CD4+ T-cell dynamics until the end of suppression or up to 5 years, subdivided into three periods: 1st year, years 2-3 and years 4-5 of suppression. Multiple median regression adjusted for repeated CD4+ T-cell measurements was used to study the dependence of CD4+ T-cell slopes on clinical covariates and drug classes. RESULTS: Median CD4+ T-cell increases following VL suppression were 87, 52 and 19 cells/microl per year in the three periods. In the multiple regression model, median CD4+ T-cell increases over all three periods were significantly higher for female gender, lower age, higher VL at cART start, CD4+ T-cell <650 cells/microl at start of the period and low CD4+ T-cell increase in the previous period. Patients on tenofovir showed significantly lower CD4+ T-cell increases compared with stavudine. CONCLUSIONS: In our observational study, long-term CD4+ T-cell increase in drug-naive patients with suppressed VL was higher in regimens without tenofovir. The clinical relevance of these findings must be confirmed in, ideally, clinical trials or large, collaborative cohort projects but could influence treatment of older patients and those starting cART at low CD4+ T-cell levels. 相似文献
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Manganini M Serafini M Bambacioni F Casati C Erba E Follenzi A Naldini L Bernasconi S Gaipa G Rambaldi A Biondi A Golay J Introna M 《Human gene therapy》2002,13(15):1793-1807
We have investigated the capacity of two human immunodeficiency virus type 1-derived lentivectors, differing in the presence of a 118-bp pol fragment containing the cPPT/CTS element, to transduce human normal primary cells of different hematopoietic lineages. Infection of resting monocytes with a high multiplicity of infection (MOI > 10) revealed that the lentivirus carrying the pol fragment (cPPT) is effective, transducing 75% of cells compared with 36% for the no-cPPT vector. Even at low MOIs (< or =1) the cPPT vector still shows a better transduction efficiency than the no-cPPT vector. Moreover, transduction does not require dendritic cell differentiation. In contrast, infection of nonactivated T lymphocytes showed that both vectors, tested at high MOIs, can transduce a small, although measurable, percentage of cells (up to 10%), which may correspond to G(1a) "activated" cells as detected by simultaneous staining of DNA and RNA, in our cultures in the presence of medium alone. Furthermore, we show that the sole addition of interleukin 2 or interleukin 15 represents a full proliferative signal under our conditions and permits high transduction efficiency (up to 30% with the cPPT vector and 15% with the no-cPPT vector). Still higher transduction of T lymphocytes can be achieved after stimulation with phytohemagglutinin and interleukin 2 (up to 78% with the cPPT vector vs. 42% with the no-cPPT vector). Finally, both viruses do not transduce either resting or proliferating tonsillar B lymphocytes. 相似文献