全文获取类型
收费全文 | 14226篇 |
免费 | 880篇 |
国内免费 | 64篇 |
专业分类
耳鼻咽喉 | 203篇 |
儿科学 | 398篇 |
妇产科学 | 317篇 |
基础医学 | 1840篇 |
口腔科学 | 980篇 |
临床医学 | 1283篇 |
内科学 | 2701篇 |
皮肤病学 | 467篇 |
神经病学 | 1343篇 |
特种医学 | 260篇 |
外科学 | 1375篇 |
综合类 | 68篇 |
一般理论 | 8篇 |
预防医学 | 1781篇 |
眼科学 | 184篇 |
药学 | 1020篇 |
中国医学 | 74篇 |
肿瘤学 | 868篇 |
出版年
2024年 | 16篇 |
2023年 | 116篇 |
2022年 | 226篇 |
2021年 | 427篇 |
2020年 | 266篇 |
2019年 | 400篇 |
2018年 | 451篇 |
2017年 | 307篇 |
2016年 | 393篇 |
2015年 | 440篇 |
2014年 | 558篇 |
2013年 | 787篇 |
2012年 | 1150篇 |
2011年 | 1281篇 |
2010年 | 664篇 |
2009年 | 534篇 |
2008年 | 876篇 |
2007年 | 998篇 |
2006年 | 870篇 |
2005年 | 839篇 |
2004年 | 687篇 |
2003年 | 598篇 |
2002年 | 582篇 |
2001年 | 190篇 |
2000年 | 162篇 |
1999年 | 141篇 |
1998年 | 89篇 |
1997年 | 86篇 |
1996年 | 68篇 |
1995年 | 61篇 |
1994年 | 54篇 |
1993年 | 43篇 |
1992年 | 76篇 |
1991年 | 84篇 |
1990年 | 75篇 |
1989年 | 57篇 |
1988年 | 44篇 |
1987年 | 53篇 |
1986年 | 44篇 |
1985年 | 40篇 |
1984年 | 35篇 |
1983年 | 51篇 |
1982年 | 29篇 |
1981年 | 22篇 |
1980年 | 16篇 |
1979年 | 23篇 |
1977年 | 14篇 |
1974年 | 15篇 |
1972年 | 14篇 |
1970年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
961.
962.
Superior survival and proliferation after transplantation of myoblasts obtained from adult mice compared with neonatal mice 总被引:6,自引:0,他引:6
BACKGROUND: Myoblast transfer therapy (MTT) is a strategy designed to compensate for the defective gene in myopathies such as Duchenne muscular dystrophy (DMD). Experimental MTT in the mdx mouse (an animal model of DMD) has used donor myoblasts derived from mice of various ages; however, to date, there has been no direct quantitative comparison between the efficacy of MTT using myoblasts isolated from adult and neonate donor muscle. METHODS: Donor normal male myoblasts were injected into Tibialis Anterior muscles of dystrophic female host mice and the survival and proliferation of male myoblasts quantitated using Y-chromosome specific real-time quantitative polymerase chain reaction. The survival of late preplate (PP6) myoblasts derived from neonatal (3-5 days old) or adult (6-8 weeks old) donor mice after MTT were compared. The influence of the number of tissue culture passages, on survival post-MTT, was also evaluated for both types of myoblasts. RESULTS: Surprisingly, superior transplantation efficiency was observed for adult-derived compared with neonatal myoblasts (both early and late passage). Extended expansion (>17 passages) in tissue culture resulted in inferior survival and proliferation of both adult and neonatal myoblasts; however, proliferation of early passage myoblasts (both adult and neonate) was evident between 3 weeks and 3 months. CONCLUSIONS: Myoblasts derived from neonatal mice were inferior for transplantation, and early passage donor myoblasts from adult mice are recommended for MTT in this model. 相似文献
963.
964.
Antonelli A Tanello M Zanotelli T Frego E Tardanico R Cosciani Cunico S 《Urologia internationalis》2004,72(1):79-81
Bladder myofibroblastic inflammatory tumors are rare benign proliferative lesions that can simulate both urothelial and connective tissue malign neoplasms, making a preoperative diagnosis nearly impossible. Conservative treatment appears to be curative, even though local recurrences have been reported, and so malignancy should be ruled out above all by means of an accurate follow-up. Two cases are described, 1 of which with the longest follow-up period reported so far (8 years). 相似文献
965.
Evaluation of magnetic fluid hyperthermia in a standard rat model of prostate cancer 总被引:4,自引:0,他引:4
Johannsen M Jordan A Scholz R Koch M Lein M Deger S Roigas J Jung K Loening S 《Journal of endourology / Endourological Society》2004,18(5):495-500
PURPOSE: To examine the feasibility and potential of magnetic fluid hyperthermia (MFH) as a minimally invasive method for hyperthermia treatment of prostate cancer. MATERIALS AND METHODS: Orthotopic Dunning R3327 prostate tumors were induced in 20 male Copenhagen rats. The animals either received MFH treatment following intratumoral administration of magnetic fluids or were used as either tumor growth controls for determination of iron distribution in selected organs or as histologic controls without MFH treatment. The MFH treatments were carried out at 45 degrees C or 50 degrees C using an AC magnetic field applicator system designed for small animals. RESULTS: Sequential treatments with MFH were possible following a single intratumoral injection of magnetic fluid. Intratumoral temperatures of 50 degrees C and more were obtained and were monitored online using fluoro-optic thermometry. Four days after MFH treatments, 79% of the injected dose of ferrites was still present in the prostate. CONCLUSIONS: The successful intraprostatic nanoparticle infiltration and stable steady-state intratumoral treatment temperatures demonstrate the feasibility of MFH in a prostate cancer model. Efficacy and survival benefit must be confirmed in further experiments. 相似文献
966.
Collogan LK Tuma F Dolan-Sewell R Borja S Fleischman AR 《Journal of traumatic stress》2004,17(5):363-372
In January 2003, The New York Academy of Medicine and the National Institute of Mental Health sponsored a meeting entitled "Ethical Issues Pertaining to Research in the Aftermath of Disaster." The purpose of the meeting was to bring together various experts to examine evidence concerning the impact of research on trauma-exposed participants, review the applicable ethical principles and policies concerning protection of human subjects, and offer guidance to investigators, IRBs, public health and local officials, and others interested in assuring that research in the aftermath of a disaster is conducted in a safe and ethical manner. This article summarizes the group's key findings and outlines potential considerations for those working in this field. 相似文献
967.
Arbeiter K Pichler A Stemberger R Mueller T Ruffingshofer D Vargha R Balzar E Aufricht C 《Pediatric nephrology (Berlin, Germany)》2004,19(2):222-226
Currently, there are no data available on long-term effects of angiotensin-converting enzyme inhibitors (ACE-I) on graft function in children after renal transplantation. We therefore analyzed all children who were transplanted at our institution between 1989 and 1998 and followed for at least 2 years. Those treated with ACE-I, mainly because of failure of other antihypertensive medications, were compared to those without ACE-I. The ACE-I-treated children (n=19) showed significantly better blood pressure control during the 1st year of follow-up (p<0.05). In children with chronic allograft dysfunction (n=8), treatment with ACE-I stabilized graft function, with improvement in creatinine clearance in 50% (p<0.01). Serum potassium and hemoglobin levels remained stable. One patient discontinued ACE-I because of renal artery stenosis. Taken together, ACE-I were effective and safe in the treatment of hypertension in children following renal transplantation. Children with chronic allograft dysfunction experienced a stabilizing effect on graft function. 相似文献
968.
Maria?Teresa?PepatoEmail author Amanda?Martins?Baviera Regina?Célia?Vendramini Iguatemy?Louren?o?Brunetti 《BMC complementary and alternative medicine》2004,4(1):7
Background
Previous experiments have shown that a decoction of Bauhinia forficata leaves reduces the changes in carbohydrate and protein metabolism that occur in rats with streptozotocin-induced diabetes. In the present investigation, the serum activities of enzymes known to be reliable toxicity markers were monitored in normal and streptozotocin-diabetic rats to discover whether the use of B. forficata decoction has toxic effects on liver, muscle or pancreas tissue or on renal microcirculation. 相似文献969.
Surfactants are amphiphilic substances with special properties and chemical structures that allow a reduction in interfacial tension, which permits an increase in molecule solubilization. The critical micelle concentration (CMC) is an important characteristic of surfactants that determines their aggregate state, which is generally related to its functional mechanism. In this work the genotoxic potential of saponified coconut oil (SCO), a surfactant obtained from Cocos nucifera, was analyzed using prokaryote systems. DNA strand breaks were not observed after treatment of a plasmid with SCO. Negative results were also obtained in the SOS Chromotest using Escherichia coli strains PQ35 and PQ37. A moderate toxicity of SCO was observed after treatment of strain CC104 with a concentration above its CMC, in which micelles were found. Nevertheless, this treatment was not cytotoxic to a CC104mutMmutY strain. Furthermore, in this DNA repair-deficient strain treatment with a SCO dose below its CMC, in which only monomers were found, demonstrated the possibility of an antioxidant effect, since a reduction in spontaneous mutagenesis frequency was observed. Finally, in an Ames test without metabolic activation mutagenicity induction was observed in strains TA100 and TA104 with treatment doses below the CMC. The cytotoxic, antioxidant and mutagenic effects of SCO can be influenced by the aggregational state. 相似文献
970.
Sentence comprehension abilities were investigated in a patient with semantic dementia who was administered tests of semantic knowledge and sentence comprehension over a 5-year period. Results showed that despite a severe and continual degradation in semantic knowledge, syntactic comprehension abilities remained largely intact. Evidence was also found for a codependency between semantics and syntax in a task in which knowledge about conceptual number influenced subject-verb agreement in the patient and in control participants. Results are discussed in relation to the nature of the sentence comprehension impairment in semantic dementia and with reference to the modularity of the components of the language processing system. 相似文献