全文获取类型
收费全文 | 23829篇 |
免费 | 1504篇 |
国内免费 | 307篇 |
专业分类
耳鼻咽喉 | 526篇 |
儿科学 | 231篇 |
妇产科学 | 356篇 |
基础医学 | 4132篇 |
口腔科学 | 458篇 |
临床医学 | 1906篇 |
内科学 | 4485篇 |
皮肤病学 | 913篇 |
神经病学 | 2040篇 |
特种医学 | 1615篇 |
外科学 | 3043篇 |
综合类 | 68篇 |
现状与发展 | 1篇 |
一般理论 | 3篇 |
预防医学 | 817篇 |
眼科学 | 554篇 |
药学 | 2333篇 |
中国医学 | 328篇 |
肿瘤学 | 1831篇 |
出版年
2024年 | 16篇 |
2023年 | 175篇 |
2022年 | 641篇 |
2021年 | 990篇 |
2020年 | 452篇 |
2019年 | 689篇 |
2018年 | 826篇 |
2017年 | 612篇 |
2016年 | 990篇 |
2015年 | 1237篇 |
2014年 | 1529篇 |
2013年 | 1676篇 |
2012年 | 2376篇 |
2011年 | 2181篇 |
2010年 | 1403篇 |
2009年 | 1165篇 |
2008年 | 1542篇 |
2007年 | 1414篇 |
2006年 | 1161篇 |
2005年 | 1064篇 |
2004年 | 811篇 |
2003年 | 726篇 |
2002年 | 584篇 |
2001年 | 275篇 |
2000年 | 237篇 |
1999年 | 165篇 |
1998年 | 97篇 |
1997年 | 89篇 |
1996年 | 63篇 |
1995年 | 55篇 |
1994年 | 44篇 |
1993年 | 38篇 |
1992年 | 43篇 |
1991年 | 45篇 |
1990年 | 40篇 |
1989年 | 27篇 |
1988年 | 23篇 |
1987年 | 29篇 |
1986年 | 12篇 |
1985年 | 12篇 |
1984年 | 19篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 9篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1971年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Post-transplantation diabetes is better controlled after conversion from prednisone to deflazacort: a prospective trial in renal transplants 总被引:2,自引:0,他引:2
Yu Seun Kim Myoung Soo Kim Soon Il Kim Seung Kil Lim Ho Yung Lee Dae Suk Han Kiil Park 《Transplant international》1997,10(3):197-201
It is well known that long-term use of steroids plays a decisive role in the development of glucose intolerance and diabetes
mellitus (DM). Deflazacort, an oxazoline derivative of prednisolone, has been introduced as a potential substitute for conventional
steroids in order to ameliorate glucose intolerance. We initiated a randomized study of conversion from prednisone to deflazacort
in kidney transplantation (Tx) recipients presenting with pre-Tx or post-Tx DM to ascertain whether or not the switch to deflazacort
would ameliorate the diabetic state. Forty-two recipients in the conversion group were compared with 40 patients on prednisone
(the control group) in a prospective manner. The dose reduction of insulin or oral blood glucose-lowering agents, the adequacy
of glucose control, and the development of side effects were the criteria for evaluating outcome. In the conversion group,
patients were switched to deflazacort at a dose ratio of 6 mg deflazacort to 5 mg prednisone. During the mean follow-up period
of 13.2 months, neither graft dysfunction nor acute rejection developed in the conversion group. Improvement in blood glucose
control in the conversion group was noted. When the conversion group was stratified into pre- or post-Tx DM, promising effects
were clearly evident in the post-Tx DM patients. More than 50 % dose reduction of blood glucose-lowering agents was possible
in 42.3 % of post-Tx DM patients. In conclusion, it was readily possible to control blood glucose better in post-Tx DM recipients
without seriously affecting the immunosuppressive activity after conversion to deflazacort.
Received: 20 August 1996 Received after revision: 25 November 1996 Accepted: 6 December 1996 相似文献
12.
13.
Blockade of LTB4-induced chemotaxis by bioactive molecules interfering with the BLT2-Gαi interaction
BLT2, a low-affinity leukotriene B4 (LTB4) receptor, is a member of the G-protein coupled receptor (GPCR) family and is involved in the pathogenesis of inflammatory diseases such as asthma. Despite its clinical implications, however, no pharmacological inhibitors are available. In the present study, we screened for small molecules that interfere with the interaction between the third intracellular loop region of BLT2 (BLT2iL3) and the Gαi3 protein subunit (Gαi3), using a high-throughput screening (HTS) assay with a library of 1040 FDA-approved drugs and bioactive compounds. We identified two small molecules—purpurin [1,2,4-trihydroxy-9,10-anthraquinone; IC50 = 1.6 μM for BLT2] and chloranil [tetrachloro-1,4-benzoquinone; IC50 = 0.42 μM for BLT2]—as specific BLT2-blocking agents. We found that blockade of the BLT2iL3-Gαi3 interaction by these small molecules inhibited the BLT2-downstream signaling cascade. For example, BLT2-signaling to phosphoinositide-3 kinase (PI3K)/Akt phosphorylation was completely abolished by these molecules. Furthermore, we observed that these small molecules blocked LTB4-induced chemotaxis by inhibiting the BLT2-PI3K/Akt-downstream, Rac1-reactive oxygen species-dependent pathway. Taken together, our results show that purpurin and chloranil interfere with the interaction between BLT2iL3 and Gαi3 and thus block the biological functions of BLT2 (e.g., chemotaxis). The present findings suggest a potential application of purpurin and chloranil as pharmacological therapeutic agents against BLT2-associated inflammatory human diseases. 相似文献
14.
15.
Yoon-Ho Hong Jung-Joon Sung Kyung Seok Park Ohyun Kwon Ju-Hong Min Kwang-Woo Lee 《Clinical neurophysiology》2007,118(12):2605-2611
OBJECTIVE: To address the issue as to how best to perform statistical MUNE, we applied two different approaches and compared results in healthy subjects and ALS patients. METHODS: Twelve normal subjects (women 8, mean age 52years) and 11 ALS patients (women 4, mean age 54years) underwent two consecutive MUNE studies, which differed in terms of setting and modifying the recording window. These are referred to as the 'expansion' and 'narrowing' methods, respectively. Size-weighted average (Av) SMUP and MUNE values were obtained using the two methods, and compared in control and patient groups. RESULTS: Expansion method-derived Av SMUP sizes and MUNE values differed only slightly from those obtained using the narrowing method in healthy subjects, whereas the narrowing method resulted in significantly larger Av SMUP sizes and smaller MUNE values than the expansion method in ALS patients (Wilcoxon signed ranks test, p=0.003). The sizes of tested areas (mean+/-SD) were significantly larger for the narrowing method than the expansion method in both subject groups with much greater difference in ALS patients; 9.6+/-3.1% vs. 7.9+/-1.7% in healthy subjects and 16.1+/-5.1% vs. 11.2+/-3.0% in ALS patients (Student t-test, p<0.01). CONCLUSIONS: The present study shows, unlike that found in normal subjects, that the results of statistical MUNE in ALS patients are heavily dependent on the approach used to set and modify recording windows. SIGNIFICANCE: The expansion method using a 10%-sized window is likely to suffer from systemic errors due to the ceiling effect and the sampling of artifactually small motor units in ALS patients. The authors recommend that the narrowing method be considered as an alternative that avoids these problems. 相似文献
16.
Suk Hee Heo Yong Yeon Jeong Sang Soo Shin Tae Woong Chung Heoung Keun Kang 《Korean journal of radiology》2007,8(2):180-183
We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma. 相似文献
17.
Detailed Diurnal Rhythm of Sensitivity to Melatonin Injections in Turkish Hamsters, Mesocricetus brandti 总被引:1,自引:0,他引:1
A diurnal rhythm of sensitivity to exogenous melatonin was defined in adult male Turkish hamsters, Mesocricetus brandti. Melatonin was administered daily by subcutaneous injections (15 micrograms in 0.1 ml 10% ethanolic saline) for 10 weeks in animals exposed to 16 L:8 D. As in golden and Djungarian hamsters, two periods of melatonin sensitivity were identified. The first, in late afternoon, persisted for 6 hr, from 7 hr to 1 hr before lights off. The second period was briefer, of only 2 hr duration in the late night, terminating at the time of lights on. Melatonin injections given during these sensitive periods promoted testicular regression in most animals; melatonin administered at other times of the day was without effect on testicular function in most animals of these groups. Gonadal regression induced by properly timed melatonin injections was rapid, in many groups nearly complete in 6 to 7 weeks. The results are discussed in relation to the function of pineal melatonin in photoperiodic time measurement in hamsters. 相似文献
18.
Enhancement of hepatic hemangiomas with levovist on coded harmonic angiographic ultrasonography. 总被引:5,自引:0,他引:5
Jung Hoon Kim Tae Kyoung Kim Bong Soo Kim Hyo Won Eun Pyo Nyun Kim Moon-Gyu Lee Hyun Kwon Ha 《Journal of ultrasound in medicine》2002,21(2):141-148
OBJECTIVE: To evaluate the pattern of contrast enhancement with Levovist on coded harmonic angiographic ultrasonography of hepatic hemangiomas. METHODS: Twenty hemangiomas were evaluated with coded harmonic angiographic ultrasonography and a microbubble contrast agent. Verification of the diagnosis of a hemangioma was made by means of dynamic computed tomography (n = 8), dynamic magnetic resonance imaging (n = 1), radionuclide scanning (n = 6), or follow-up ultrasonography (n = 5). Ultrasonographic images were obtained before contrast agent administration and with a bolus injection of 2.5 g of a microbubble contrast agent (300 mg/mL Levovist; Schering AG, Berlin, Germany) every 10 to 15 seconds for 5 minutes. The contrast enhancement patterns of the 20 hemangiomas were assessed. RESULTS: The tumor diameters as measured on ultrasonography were 7 to 97 mm (mean, 26.7 mm). Of the 20 hemangiomas, peripheral globular enhancement with progressive centripetal fill-in was shown in 15 (75%), rimlike enhancement with progressive centripetal fill-in was shown in 2 (10%), and homogeneous enhancement was shown in 1 (5%). In the remaining 2 lesions (10%), the enhancement patterns could not be seen, because they were not found on coded harmonic angiographic ultrasonography. CONCLUSIONS: Coded harmonic angiographic ultrasonography with a microbubble contrast agent can depict the typical enhancement pattern in most hepatic hemangiomas. 相似文献
19.
Seung Min Lee Seung Kyung Hann Soo II Chun Seung Hung Lee Yoon-Kee Park 《The Journal of dermatology》1994,21(2):106-110
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin. 相似文献
20.