全文获取类型
收费全文 | 17417篇 |
免费 | 812篇 |
国内免费 | 94篇 |
专业分类
耳鼻咽喉 | 177篇 |
儿科学 | 382篇 |
妇产科学 | 359篇 |
基础医学 | 1980篇 |
口腔科学 | 1454篇 |
临床医学 | 1166篇 |
内科学 | 4554篇 |
皮肤病学 | 433篇 |
神经病学 | 1413篇 |
特种医学 | 300篇 |
外科学 | 2521篇 |
综合类 | 93篇 |
一般理论 | 5篇 |
预防医学 | 1241篇 |
眼科学 | 372篇 |
药学 | 757篇 |
中国医学 | 81篇 |
肿瘤学 | 1035篇 |
出版年
2024年 | 11篇 |
2023年 | 132篇 |
2022年 | 275篇 |
2021年 | 584篇 |
2020年 | 332篇 |
2019年 | 531篇 |
2018年 | 616篇 |
2017年 | 408篇 |
2016年 | 423篇 |
2015年 | 524篇 |
2014年 | 739篇 |
2013年 | 902篇 |
2012年 | 1459篇 |
2011年 | 1584篇 |
2010年 | 896篇 |
2009年 | 733篇 |
2008年 | 1201篇 |
2007年 | 1367篇 |
2006年 | 1156篇 |
2005年 | 1015篇 |
2004年 | 896篇 |
2003年 | 742篇 |
2002年 | 757篇 |
2001年 | 91篇 |
2000年 | 63篇 |
1999年 | 76篇 |
1998年 | 117篇 |
1997年 | 97篇 |
1996年 | 82篇 |
1995年 | 53篇 |
1994年 | 57篇 |
1993年 | 44篇 |
1992年 | 25篇 |
1991年 | 24篇 |
1990年 | 25篇 |
1989年 | 11篇 |
1988年 | 17篇 |
1987年 | 15篇 |
1986年 | 12篇 |
1985年 | 13篇 |
1984年 | 26篇 |
1983年 | 21篇 |
1982年 | 12篇 |
1981年 | 24篇 |
1980年 | 21篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1977年 | 18篇 |
1976年 | 13篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
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
62.
Eduardo Bruera J Lynn Palmer Snezana Bosnjak Maria Antonieta Rico Jairo Moyano Catherine Sweeney Florian Strasser Jie Willey Mariela Bertolino Clarissa Mathias Odette Spruyt Michael J Fisch 《Journal of clinical oncology》2004,22(1):185-192
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain. 相似文献
63.
Tania Crombet Marta Osorio Teresa Cruz Carlos Roca Ramón del Castillo Rosa Mon Normando Iznaga-Escobar René Figueredo James Koropatnick Enrique Renginfo Eduardo Fernández Daniel Alvárez Olga Torres Mayra Ramos Idrissa Leonard Rolando Pérez Agustín Lage 《Journal of clinical oncology》2004,22(9):1646-1654
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms. 相似文献
64.
65.
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
66.
Gustavo Adolfo Avila Montes Mercedes Martínez Catalina Sherman Eduardo Fernández Cerna 《Pan American journal of public health》2004,16(2):84-94
OBJECTIVE: To evaluate the effectiveness of a special course on environmental health and dengue, given to primary school students and intended to promote behavioral changes in the mothers of those students that would lead to the safe handling of water, adequate disposal of trash, and control of household breeding sites of Aedes aegypti, the mosquito vector for dengue. METHODS: In the period from April to November 2002 a community field trial was carried out that included four public schools in the city of Comayaguela, Honduras. Two of the schools formed the intervention group, and the two others made up the comparison or control group. The data collection activities before and after the intervention included knowledge tests for the schoolchildren and the teachers; surveys of the knowledge, attitudes, and practices of the students' mothers; entomological surveys (systematic checking in order to find water containers, to search for mosquito larvae) in the homes of the schoolchildren; in-depth interviews with the students' mothers; observation in the classrooms; and postintervention focus group with the teachers. RESULTS: During the intervention period the largest epidemic of classical dengue ever in the history of Tegucigalpa, the capital of Honduras, occurred. That event prompted the Secretariat of Health to undertake large-scale control activities. In the two intervention schools there was a significant increase in the students' knowledge of the following three variables: dengue caused by a virus, life cycle of the vector, and reduction of breeding sites, which is the most effective measure for controlling the vector (P < 0.0001 for all those increases in knowledge). There were also significant increases in the knowledge of the same variables among the teachers in the intervention schools: dengue caused by a virus (P = 0.03), life cycle of the vector (P = 0.01), and reduction of breeding sites (P = 0.004). Reducing the number of breeding sites as being the best measure for controlling Aedes aegypti was the knowledge variable that showed the greatest change among the mothers in the intervention group (P = 0.02). The values for two of the entomological indices (the House index and the Breteau index) were better in the intervention group than in the control group, but the difference was not statistically significant. However, there was a statistically significant difference in the Breteau index values between the two control group schools and the one intervention school where the education course was implemented more adequately than in the other intervention school. CONCLUSIONS: The application of educational interventions directed to schoolchildren, as a part of a comprehensive plan for controlling Aedes aegypti, is an effective way to raise the awareness of teachers and parents with respect to the problem of dengue, and it also helps in encouraging family members to be involved in reducing breeding sites in the home. In moving to control the dengue vector, this strategy should take into consideration the involvement not only of families but also of civic and public institutions in the community. Given our results, it appears that this approach of using a special course for schoolchildren can constitute a fundamental pillar in the strategy for integrated dengue control. 相似文献
67.
A field of study for public health finance has never been adequately developed. Consequently, very little is known about the relationships, types, and amount of finances that fund the public health system in America. This research was undertaken to build on the sparse knowledge of public health finance by examining the value of performance measurement systems to financial analysis. A correlational study was conducted to examine the associations between public health system performance of the 10 essential public health services and funding patterns of 50 local health departments in a large state. The specific objectives were to investigate if different levels and types of revenues, expenditures, and other demographic variables in a jurisdiction are correlated to performance. Pearson correlation analysis did not conclusively show strong associations; however, statistically significant positive associations primarily between higher levels of performance and jurisdiction taxes per capita were found. 相似文献
68.
Giangennaro Coppola J?rg Klepper Eduardo Ammendola Monica Fiorillo Rita della Corte Guglielmo Capano Antonio Pascotto 《European journal of paediatric neurology》2006,10(3):148-151
PURPOSE: Tuberous sclerosis complex (OMIM 191100) is a multiorgan disease commonly associated with epilepsy refractory to anticonvulsants. Individual reports indicate that seizures in children with tuberous sclerosis might benefit from a ketogenic diet. We studied the effects of the diet introduced at 3.5 years of age in three boys with tuberous sclerosis and refractory partial seizures. METHODS: On admission a classical LCT ketogenic diet was initiated and patients were followed for 12 months. Antiepileptic drugs were maintained unless adverse effects required reduction. RESULTS: Two patients became seizure-free within 2 months on the diet. In the third patient drop attacks decreased significantly. On follow-up the diet was well accepted and without adverse effects. CONCLUSION: The ketogenic diet should be considered as a treatment option for children with tuberous sclerosis and partial seizures refractory to anticonvulsants. Our data support the need for further studies in larger cohorts to confirm the effectiveness of the ketogenic diet in this entity. 相似文献
69.
Javier Sastre Eugenio Marcuello Bartomeu Masutti Matilde Navarro Silvia Gil Antonio Antón Albert Abad Enrique Aranda Joan Maurel Manuel Valladares Inmaculada Maestu Alfredo Carrato José María Vicent Eduardo Díaz-Rubio 《Journal of clinical oncology》2005,23(15):3545-3551
PURPOSE: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients. PATIENTS AND METHODS: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion. RESULTS: By intent-to-treat analysis, in 85 assessable patients, the objective response rate was 35% (95% CI, 25% to 46%), and stable disease was 33% (95% CI, 23% to 44%). Median time to progression was 8.0 months (95% CI, 6.0 to 10.0 months), and median overall survival time was 15.3 months (95% CI, 13.8 to 16.9 months). Toxicity was moderate. Grade 3 and 4 neutropenia, diarrhea, and asthenia were observed in 21%, 17%, and 13% of patients, respectively. Only one case of neutropenic fever occurred. There were two toxic deaths, one was a result of grade 4 diarrhea and acute kidney failure, and the other was a result of massive intestinal hemorrhage in the first cycle. The study of prognostic factors did not reveal any predictive factor of response. Response to treatment and baseline lactate dehydrogenase were the main factors conditioning progression-free and overall survival. CONCLUSION: Twice a month continuous-infusion CPT-11 combined with FU is a valid therapeutic alternative for elderly patients in good general condition. 相似文献
70.
Fernando Moreno Antón Javier Sastre Valera Belén Loboff de León Sara López-Tarruella Luis Ortega Medina Eduardo Díaz-Rubio 《Clinical & translational oncology》2005,7(7):321-323
Metastastic tumours involving the epididymis are rare and most often found in patients with disseminated disease. It is even more unusual when the metastasis of the epididymis is the first sign of tumour recurrence. We report a case of an asymptomatic recurrent colon carcinoma presenting as metastasis in the epididymis. Although metastatic cancer presenting as an intra-scrotal mass is extremely rare, it should be considered as a possibility in patients who present with a mass involving the testicle or epididymis. 相似文献