全文获取类型
收费全文 | 20466篇 |
免费 | 1473篇 |
国内免费 | 84篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 519篇 |
妇产科学 | 354篇 |
基础医学 | 2779篇 |
口腔科学 | 514篇 |
临床医学 | 2403篇 |
内科学 | 4093篇 |
皮肤病学 | 367篇 |
神经病学 | 1896篇 |
特种医学 | 857篇 |
外科学 | 3104篇 |
综合类 | 113篇 |
一般理论 | 2篇 |
预防医学 | 1672篇 |
眼科学 | 349篇 |
药学 | 1350篇 |
中国医学 | 47篇 |
肿瘤学 | 1477篇 |
出版年
2023年 | 171篇 |
2022年 | 209篇 |
2021年 | 398篇 |
2020年 | 310篇 |
2019年 | 416篇 |
2018年 | 520篇 |
2017年 | 471篇 |
2016年 | 446篇 |
2015年 | 475篇 |
2014年 | 654篇 |
2013年 | 912篇 |
2012年 | 1260篇 |
2011年 | 1314篇 |
2010年 | 659篇 |
2009年 | 600篇 |
2008年 | 1055篇 |
2007年 | 1078篇 |
2006年 | 1055篇 |
2005年 | 882篇 |
2004年 | 873篇 |
2003年 | 794篇 |
2002年 | 773篇 |
2001年 | 407篇 |
2000年 | 478篇 |
1999年 | 432篇 |
1998年 | 227篇 |
1997年 | 177篇 |
1996年 | 164篇 |
1995年 | 170篇 |
1994年 | 151篇 |
1993年 | 139篇 |
1992年 | 343篇 |
1991年 | 349篇 |
1990年 | 337篇 |
1989年 | 280篇 |
1988年 | 257篇 |
1987年 | 299篇 |
1986年 | 283篇 |
1985年 | 222篇 |
1984年 | 217篇 |
1983年 | 209篇 |
1982年 | 117篇 |
1981年 | 100篇 |
1979年 | 135篇 |
1978年 | 96篇 |
1977年 | 86篇 |
1975年 | 86篇 |
1974年 | 78篇 |
1973年 | 83篇 |
1970年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Jensen ME 《Journal of health care chaplaincy》2002,12(1-2):113-123
The article considers the issues raised by Chaplain Yes and Chaplain No earlier in this volume. They are considered in the framework of the distinctive dimensions of a profession. I contend that chaplaincy could be served by internal discussions of specialized skills and goals it wants to claim in the professional sphere, and that scientific tools could be used to evaluate, refine, and communicate those skills and goals. Possibilities include benchmarks, outcomes research, and inclusion of "consumers" in research designs. I argue that distinctive core skills and competencies of chaplaincy lie in affective, intuitive, and symbolic domains more than scientific domains, but that chaplaincy can benefit from strategic utilization of tools moore native to other disciplines. I caution against reductionism from either domain, while arguing for vigorous dialogue. 相似文献
992.
This review analyzes the literature and the historical concerns (restrictions, traditions, nasogastric tube) and pathophysiologic factors (postoperative ileus, risk of anastomotic dehiscence, nausea and vomiting, loss of appetite) invoked for not instituting early oral feeding after major abdominal procedures. It appears that several factors may promote postoperative oral feeding such as thoracic epidural analgesia, multimodal anti-emetic treatment, opioid-sparing analgesia, selective peripheral opioid antagonists, and enforced oral nutrition. Recent data from multimodal fast-track rehabilitation surgical programs in abdominal surgery provide a rational basis for future studies to investigate and facilitate enforced oral feeding after major abdominal procedures. 相似文献
993.
Lajer H Daugaard G Andersson AM Skakkebaek NE 《International journal of cancer. Journal international du cancer》2002,100(2):244-246
TRA-1-60 antigen has been related to the presence of embryonal germ cell carcinoma (EC) and carcinoma in situ. Our study further investigated the clinical efficacy of TRA-1-60 as a serum tumor marker for germ cell cancer in the testis. Three groups of patients with germ cell tumors were included: Group 1, 34 patients with disseminated disease (24 nonseminomatous germ cell tumors [NSGCT] and 10 seminomatous germ cell tumors [SGCT]); this group of patients were followed during the course of chemotherapy with measurements of TRA-1-60, HCG and AFP; Group 2, 28 patients with Stage I NSGCT (22 with embryonal carcinoma [EC]-component and 6 without EC-component, median follow-up 15 months); and Group 3, 40 patients with Stage I pure SGCT (median follow-up 15 months). Seventy-eight percent of patients with disseminated EC-positive NSGCT had increased levels of TRA-1-60 before chemotherapy. After chemotherapy, levels of TRA-1-60 had dropped significantly (p < 0.01). Levels of TRA-1-60 did not normalize in 15% of NSGCT and 30% of SGCT patients after chemotherapy. This was not associated with recurrent disease. Approximately one-third of patients with Stage I NSGCT had increased values of TRA-1-60 during follow-up without having a relapse. Contrary to earlier reports TRA-1-60 is not at present useful as a tumor marker in patients with germ cell tumors. Although detecting a few early relapses the rate of false positive elevations in the tumor marker makes it unreliable in the clinical setting. Our study did confirm that elevated levels of TRA-1-60 were present in approximately 80% of patients with disseminated EC-positive NSGCT before start of chemotherapy and chemotherapy induced a significant decrease in levels of TRA-1-60. Thus, the TRA-1-60 antigen might still prove clinically useful provided that the reliability of the assay can be increased. 相似文献
994.
Translation of microarray data into clinically relevant cancer diagnostic tests using gene expression ratios in lung cancer and mesothelioma 总被引:18,自引:0,他引:18
Gordon GJ Jensen RV Hsiao LL Gullans SR Blumenstock JE Ramaswamy S Richards WG Sugarbaker DJ Bueno R 《Cancer research》2002,62(17):4963-4967
The pathological distinction between malignant pleural mesothelioma (MPM)and adenocarcinoma (ADCA) of the lung can be cumbersome using established methods. We propose that a simple technique, based on the expression levels of a small number of genes, can be useful in the early and accurate diagnosis of MPM and lung cancer. This method is designed to accurately distinguish between genetically disparate tissues using gene expression ratios and rationally chosen thresholds. Here we have tested the fidelity of ratio-based diagnosis in differentiating between MPM and lung cancer in 181 tissue samples (31 MPM and 150 ADCA). A training set of 32 samples (16 MPM and 16 ADCA) was used to identify pairs of genes with highly significant, inversely correlated expression levels to form a total of 15 diagnostic ratios using expression profiling data. Any single ratio of the 15 examined was at least 90% accurate in predicting diagnosis for the remaining 149 samples (e.g., test set). We then examined (in the test set) the accuracy of multiple ratios combined to form a simple diagnostic tool. Using two and three expression ratios, we found that the differential diagnoses of MPM and lung ADCA were 95% and 99% accurate, respectively. We propose that using gene expression ratios is an accurate and inexpensive technique with direct clinical applicability for distinguishing between MPM and lung cancer. Furthermore, we provide evidence suggesting that this technique can be equally accurate in other clinical scenarios. 相似文献
995.
996.
Klug Albertsen B Schmiegelow K Schrøder H Carlsen NT Rosthøj S Avramis VI Jakobsen P 《Cancer chemotherapy and pharmacology》2002,50(2):117-120
PURPOSE: A case-control study was performed to determine whether patients who had been treated with Erwinia asparaginase as part of their treatment for childhood acute lymphoblastic leukemia (ALL) and who showed relapsed of their disease more often developed anti-asparaginase antibodies than patients who remained in remission. METHODS: A group of 13 patients who showed relapsed of their disease (median follow-up 35 months) were randomly matched with control patients of the same risk group (two control patients to each case), who had received therapy of the same intensity during the same period (median follow-up 70 months). Anti- Erwinia asparaginase antibodies were measured (ELISA method) during maintenance therapy after asparaginase treatment (30,000 IU/m(2) daily for 10 days in all patients plus twice weekly for 2 weeks in intermediate-risk and high-risk ALL patients). RESULTS: The overall incidence of anti- Erwinia asparaginase antibodies was 8% (3 of 39 patients). There was no statistically significant difference in the incidence of antibody formation between patients who had suffered relapse (1 of 13) and those who had not (2 of 26). In two of the three patients who developed antibodies, the antibodies disappeared after some time, whereas one patient had measurable antibody levels for more than a year after asparaginase therapy. CONCLUSIONS: In this study, the development of anti-Erwinia asparaginase antibodies was rare and was unrelated to the risk of relapse. 相似文献
997.
BACKGROUND: The authors hypothesized that impaired oxygen extraction in mitochondrial myopathy (MM) results in a high oxygen saturation in venous effluent blood from working muscle and that this phenomenon can be used as a diagnostic tool for MM. METHODS: Twelve patients with MM, 10 patients with muscular dystrophy, and 12 healthy subjects were studied. All subjects performed intermittent static handgrip exercise (1/2 Hz) at 40% of maximal voluntary contraction (MVC) for 3 minutes. Cubital venous oxygen saturation and brachial artery flow were measured in the exercised arm. RESULTS: Exercise-induced venous oxygen desaturation was smaller in patients with MM (Delta - 7 +/- 5%) than in subjects with muscular dystrophy (Delta - 38 +/- 2%; p = 0.00001) and healthy subjects (Delta - 43 +/- 2%; p = 0.0000002). MVC and exercise blood flow were similar in patients with MM (18 +/- 3 kg; 436 +/- 65 mL/min) and patients with muscular dystrophy (15 +/- 3 kg; 460 +/- 85 mL/min), but were higher in healthy subjects (32 +/- 4 kg; 630 +/- 58 mL/min; p < 0.03). In seven patients with MM and seven patients with McArdle disease, studied with a slightly different protocol, exercise-induced oxygen desaturation was also impaired in MM (Delta - +/- 5%) compared with McArdle disease (Delta - 26 +/- 3%; p = 0.007). CONCLUSION: Oxygen desaturation in venous blood from exercising muscle is markedly lower in patients with mitochondrial myopathy than in subjects with other muscle diseases and healthy subjects, suggesting that a forearm exercise test can be a diagnostic screening tool for mitochondrial myopathy. 相似文献
998.
BACKGROUND: The strong association between maternal and offspring depression has been observed in numerous studies. Understanding this association has implications for early intervention and prevention. METHOD: Findings from our community-based epidemiologic studies and high-risk and longitudinal studies of families with depression are reviewed. RESULTS AND CONCLUSIONS: The childbearing years are the high-risk period for major depression in women. The offspring of depressed women are at high risk for depression. The risk begins before puberty in the offspring and is transmitted to the grandchildren. Depression that begins in childhood or adolescence is continuous and is associated with considerable morbidity. Despite the availability of efficacious treatment, the majority of depressed adults and children remain untreated. Without a clear commitment to mental health parity and an effective service system for intervention, little progress will occur in improving the treatment of depression. There are numerous opportunities for research on the etiology, treatment, and prevention of depression in mothers and their children. 相似文献
999.
Lauritsen MB Mors O Mortensen PB Ewald H 《Journal of autism and developmental disorders》2002,32(2):115-119
Possible associations between autism and specific medical disorders have been suggested, and this could be of relevance in the clinical examination and treatment of patients and may help to identify factors involved in the etiology or pathophysiology of autism. Two population-based Danish registers were used to investigate the occurrence of medical disorders in patients with autism according to ICD-8 and in a matched control sample. A total of 29 of the 244 patients (11.9%) diagnosed with autism had one or more medical disorders. In contrast to previous studies, we did not find an increased occurrence of almost any medical disorders. A highly significant increased frequency of congenital malformations was found, which may indicate abnormalities in embryogenesis in the etiology of autism. 相似文献
1000.
Experience gained from cooperation between dermatologists and vascular surgeons in 177 patients evaluated at a joint leg ulcer clinic is reported. Patients were divided into two subgroups: (i) 86 patients with healed ulcers and (ii) 91 patients with ongoing therapy-resistant ulcers. Venous insufficiency was the most common etiology in both subgroups (87% and 55%, respectively). Of previous therapy-resistant ulcers, 71% were healed after the combined effort. The pattern of venous incompetence differed between the two subgroups; patients with isolated superficial disease constituting 68% and 26% of patients, respectively. In patients with therapy-resistant ulcers, those with isolated superficial venous insufficiency were found to have a better prognosis than those with deep venous insufficiency. Cooperation between the dermatologist and vascular surgeon is a mainstay in order to take advantage of the possibilities offered by modern vascular surgery. 相似文献