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111.
Trilla Herrera E Torrecilla Ortíz C Muñoz Seguí J Riera Canals L Suárez Novo JF Marco Pérez LM Franco Miranda E Serrallach Milá N 《Actas urologicas espa?olas》2000,24(5):423-428
First described by the end of the fifties, pelvic lipomatosis is an uncommon disease that develops as a result of an excessive proliferation of benign fat tissue within the perivesical and perirectal spaces. The compressive effect on the urinary, and to a lesser degree, the digestive and vascular structures result in the well-known symptoms. Diagnosis is reached through X-ray studies, primarily computerised tomography. Contribution of four new cases in young males diagnosed through imaging studies as well as biopsies in three of them. Evolution has been varying, with medical control of symptoms in two cases and renal function impairment due to upper obstructive uropathy in the other two. 相似文献
112.
Anita Koushik Robert W Platt Eduardo L Franco 《Cancer epidemiology, biomarkers & prevention》2004,13(1):11-22
The Arg/Arg genotype versus Arg/Pro or Pro/Pro at codon 72 of the p53 gene has been implicated as a risk marker in cervical neoplasia. However, research on this topic has produced controversial results. We reviewed the published literature to summarize the association and to identify methodological features that may have contributed to the heterogeneity. Information on specific methodological features of studies addressing this topic published between 1998 and 2002 were obtained. Study-specific odds ratios (ORs) were combined in a meta-analysis, assuming random effects. To identify characteristics that significantly contributed to heterogeneity, we used meta-regression analysis. We identified 50 articles, of which 45 were included in the meta-analyses and regressions. No evidence of association or heterogeneity was detected for preinvasive lesions. For invasive cervical cancer with undefined histology, the Arg/Arg genotype was not found to affect risk (OR, 1.1; 95% confidence interval (CI), 0.9-1.3). However, a slightly increased risk was observed for squamous cell carcinoma (OR, 1.5; 95% CI, 1.2-1.9) and adenocarcinoma (OR, 1.7; 95% CI, 1.0-2.7). Meta-regression analysis identified that the most important factor contributing to heterogeneity among results for invasive lesions was departures from Hardy-Weinberg equilibrium in the control group. Summary ORs for studies in equilibrium were essentially null. A possible susceptibility role by the p53 codon 72 polymorphism at a late carcinogenetic stage in cervical cancer cannot be ruled out. However, various methodological features can contribute to departures from Hardy-Weinberg equilibrium and consequently to less than ideal circumstances for the examination of this polymorphism. Future investigations require appropriate attention to design and methodological issues. 相似文献
113.
Francesco Izzo Paolo Marra Gerardo Beneduce Giuseppe Castello Paolo Vallone Vincenzo De Rosa Franco Cremona C Mark Ensor Frederick W Holtsberg John S Bomalaski Mike A Clark Chaan Ng Steven A Curley 《Journal of clinical oncology》2004,22(10):1815-1822
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted. 相似文献
114.
Lisa Licitra Paolo Bossi Laura Locati Franco Zunino 《Journal of clinical oncology》2004,22(2):377; author reply 377-377; author reply 378
115.
Value of P-glycoprotein and clinicopathologic factors as the basis for new treatment strategies in high-grade osteosarcoma of the extremities. 总被引:8,自引:0,他引:8
Massimo Serra Katia Scotlandi Gemma Reverter-Branchat Stefano Ferrari Maria C Manara Stefania Benini Marina Incaprera Franco Bertoni Mario Mercuri Antonio Briccoli Gaetano Bacci Piero Picci 《Journal of clinical oncology》2003,21(3):536-542
PURPOSE: To evaluate the prognostic value of P-glycoprotein and clinicopathologic parameters in a large series of high-grade osteosarcoma (OS) patients treated at the Rizzoli Institute. PATIENTS AND METHODS: With the use of immunohistochemistry, P-glycoprotein was assessed in 149 patients with primary, nonmetastatic, high-grade OS who were homogeneously treated with chemotherapy protocols based on doxorubicin, high-dose methotrexate, and cisplatin and the addition of ifosfamide in the postoperative phase. RESULTS: P-glycoprotein positivity was found in 47 of 149 cases (32%) and was significantly associated with a higher incidence of relapse and a worse outcome, as was age younger than 12 years and tumor volume greater then 150 mL at diagnosis. Multivariate analysis further confirmed the prognostic value of these parameters, which all were independent adverse prognostic factors. Event-free survival and proportional hazards regression analyses confirmed that overexpression of P-glycoprotein at clinical onset is the most important adverse prognostic factor for high-grade OS patients treated with these chemotherapy protocols. CONCLUSION: Increased P-glycoprotein levels, together with tumor volume and age, should be taken into consideration to identify, at time of diagnosis, subgroups of OS patients with a higher risk of recurrence. This subgroup identification will constitute the basis for drawing individualized treatment protocols on the basis of risk evaluation, with the aim of using more aggressive chemotherapy, or combination chemotherapy with other adjuvants, only in those patients for which more aggressive regimens are strictly necessary and warranted. 相似文献
116.
Mechanisms of proteasome inhibitor PS-341-induced G(2)-M-phase arrest and apoptosis in human non-small cell lung cancer cell lines. 总被引:10,自引:0,他引:10
Yi-He Ling Leonard Liebes Jian-Dong Jiang James F Holland Peter J Elliott Julian Adams Franco M Muggia Roman Perez-Soler 《Clinical cancer research》2003,9(3):1145-1154
PURPOSE: PS-341 is a novel dipeptide boronic acid proteasome inhibitor with in vitro and in vivo antitumor activity that induces mechanisms of apoptosis by unknown mechanisms. EXPERIMENTAL DESIGN: Human non-small cell lung cancer cell lines were used to investigate effects PS-341 on cell proliferation, cell cycle progression, and the induction of apoptosis. RESULTS: PS-341 was 38-360-fold more cytotoxic against H460 cells when compared with the proteasome inhibitors MG-132 and PSI. Differential PS-341 cytotoxic effects were found with respect to P53 function: H322 cells (p53 mutant) were 6-fold less sensitive as compared with H460 cells (p53 wild type); and H358 cells (p53 null) were 1.6-fold more sensitive as compared with H460 cells (p53 wild type). A concentration- and time-dependent cell cycle blockade at G(2)-M phase was seen for H460 cells without any direct effects on microtubule polymerization or depolymerization. PS-341 exposure in H460 cells led to stabilization of p53, induction of p21(cip/waf-1) and MDM2 expression, an increase in cyclin B and cyclin A, and the activation of cyclin B and cyclin A kinases. MDM2 induction was found only in H460 cells, whereas in H322 and H358 cells, G(2)-M-phase arrest, p21(cip/waf-1) induction, and an increase in cyclin B1 were found. The commitment of G(2)-M-phase cells to apoptosis was verified by the activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase in drug-free medium. CONCLUSIONS: Our data suggest that the PS-341-induced G(2)-M-phase arrest may be associated with the inhibition of degradation of cell cycle regulators and that the up-regulation of p21(cip/waf-1) expression may be via p53-dependent and/or -independent pathways. The resulting disturbance of cell cycle progression leads either to growth inhibition or to the initiation of apoptotic pathways. 相似文献
117.
Marie-Claude Rousseau Michal Abrahamowicz Luisa L Villa Maria Cecilia Costa Thomas E Rohan Eduardo L Franco 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1029-1037
Women infected with multiple human papillomavirus (HPV) types seem to be at higher risk of cervical intraepithelial neoplasia, although there is controversy about whether coinfections are associated with lower or higher grades of dysplasia. There is no established risk factor profile for infection with multiple HPV types. We analyzed data from a prospective cohort of 2,075 Brazilian women to identify determinants of HPV coinfection. Cervical specimens were collected for cytology and HPV DNA detection. Data on baseline and time-dependent putative risk factors were obtained by interview. Baseline predictors of HPV coinfection included younger age, greater number of recent sexual partners, a history of condyloma but not of other sexually transmitted diseases, and younger age at first sexual intercourse. In repeated measures analyses, there was a weak positive association between the number of sexual partners in the time interval between two study visits and the risk of coinfection. Our results suggest that the risk factor profile for HPV coinfection among HPV-infected women shares several similarities with risk factors for any HPV infection. 相似文献
118.
Mauro Calvani Claudia Alessandri Giuseppe Paolone Luciano Rosengard Antonino Di Caro David De Franco 《Pediatric allergy and immunology》1997,8(2):91-96
It is currently accepted that vinil infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptom-, indicative of utopic disease and EBV antibodies in 353 children aged from I month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by en/. yme imimmoassay. Dividing ihe study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s. d.) was, in total, more frequent in the EBV negative (32. 9%) than in the positive subjects (27. 6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels. 相似文献
119.
D. Soboleski B. Mussari D. McCloskey Eric Sauerbrei Franco Espinosa A. Fletcher 《Pediatric radiology》1998,28(2):79-82
Objective. The purpose of this investigation is to elucidate the sonographic features of abnormal major cranial sutures. Materials and methods. Eight excised synostosed suture specimens were evaluated. The high-resolution sonographic appearance was correlated with
the histological section, plain radiographs, CT and MRI. Diastatic and molded sutures were also evaluated with sonography
and compared with the normal cranial suture appearance. Results. Synostosed sutures demonstrated one or more of the following features: (a) loss of echo-poor fibrous gap between bony plates
(five sagittal and coronal synostoses); (b) irregular thickened inner sutural margin (three lambdoid synostoses); (c) loss
of bevelled edge (one lambdoid synostosis); (d) asymmetric anterior fontanelle (one coronal synostosis). Cranial molding results
in an overlap of echogenic bony plates. Sutural width (the distance between bony plates) is increased in cases of elevated
intracranial pressure. Conclusion. Sonography is an inexpensive, radiation-free modality which can confirm synostosis versus molding versus an underlying intracranial
lesion as a cause of plagiocephaly. The high-resolution sonographic images also provide a relatively easy means to assess
sutural width and may provide information in regard to increased intracranial pressure.
Received: 24 March 1997 Accepted: 25 September 1997 相似文献
120.
In vitro and in vivo interaction between cisplatin and topotecan in ovarian carcinoma systems 总被引:7,自引:0,他引:7
Simona Romanelli Paola Perego Graziella Pratesi Nives Carenini Monica Tortoreto Franco Zunino 《Cancer chemotherapy and pharmacology》1998,41(5):385-390
Topotecan, a camptothecin analogue, is a␣specific inhibitor of topoisomerase I approved for use in the treatment of patients
with refractory ovarian carcinoma. The drug's mechanism of action suggests a potential efficacy of drug combinations incorporating
DNA-damaging agents. In an attempt better to define a␣rational basis for drug combination we examined the effect of topotecan
on the cytotoxicity and antitumor activity of cisplatin in an ovarian carcinoma system growing in vitro and in vivo as a tumor
xenograft. The in vitro cell system included a cisplatin-sensitive cell line, IGROV-1, and a cisplatin-resistant subline,
IGROV-1/Pt0.5, which is characterized by p53 mutation and loss of normal function of the wild-type gene of the parental cell
line. This cell system was chosen since the cell sensitivity to DNA-damaging agents appears to be dependent on p53 gene status.
Cytotoxicity was assessed by the growth inhibition assay using different schedules: (a) a 1-h period of cisplatin exposure
followed by a 24-h topotecan treatment and (b) a 1-h period of simultaneous exposure to cisplatin and topotecan. In the case
of the sequential schedule, an additive interaction was observed in IGROV-1 and IGROV-1/Pt0.5 cells. When the simultaneous
schedule was used, a synergistic interaction, more evident for the cisplatin-sensitive cells, was found. On the basis of these
observations at a cellular level, the effect of concomitant administration of the two drugs (i.e., the most favorable schedule)
was studied in the IGROV-1 tumor xenograft, which is moderately responsive to cisplatin and topotecan. Suboptimal doses of
each drug (with a low dose of topotecan, 5.1 mg/kg) achieved an antitumor effect comparable with or superior to that of the
optimal dose of a single treatment (tumor weight inhibition, 60%), thus indicating a␣pharmacological advantage of the combination
over the single treatment. However, an increase in the topotecan dose (7.1 mg/kg) was associated with an evident increase
in the toxicity of the combination, thereby suggesting that the drug interaction was not tumor-specific. Although the molecular
basis of the drug interaction is not clear, it is likely that inhibition of topoisomerase I affects the ability of cells to
repair cisplatin adducts. Such findings may have pharmacological implications since they suggest the potential clinical interest
of topoisomerase I inhibitors in combination with cisplatin.
Received: 14 June 1997 / Accepted: 18 September 1997 相似文献