首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   405篇
  免费   34篇
  国内免费   2篇
儿科学   13篇
妇产科学   2篇
基础医学   75篇
口腔科学   5篇
临床医学   30篇
内科学   110篇
皮肤病学   41篇
神经病学   21篇
特种医学   14篇
外科学   39篇
综合类   3篇
预防医学   12篇
眼科学   28篇
药学   23篇
中国医学   1篇
肿瘤学   24篇
  2023年   4篇
  2022年   11篇
  2021年   25篇
  2020年   19篇
  2019年   18篇
  2018年   19篇
  2017年   18篇
  2016年   15篇
  2015年   15篇
  2014年   13篇
  2013年   21篇
  2012年   25篇
  2011年   17篇
  2010年   12篇
  2009年   8篇
  2008年   19篇
  2007年   10篇
  2006年   16篇
  2005年   14篇
  2004年   15篇
  2003年   17篇
  2002年   21篇
  2001年   5篇
  2000年   9篇
  1999年   6篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1994年   2篇
  1992年   4篇
  1991年   7篇
  1990年   1篇
  1989年   2篇
  1988年   4篇
  1987年   8篇
  1986年   4篇
  1985年   6篇
  1983年   3篇
  1981年   2篇
  1979年   3篇
  1978年   3篇
  1977年   4篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1971年   2篇
  1970年   2篇
  1969年   1篇
  1966年   4篇
排序方式: 共有441条查询结果,搜索用时 31 毫秒
1.
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.  相似文献   
2.
AIM: We administered the herbal medicine Dai-Kenchu-To (DKT) to children with severe chronic constipation or with severe constipation after surgery for anorectal malformations. We then objectively assessed the effect of DKT on anorectal function by manometric study in addition to using a clinical scoring system. PATIENTS AND METHODS: Ten children with severe chronic constipation and 5 children with severe constipation after surgery for anorectal malformations were assessed. These 15 children received 0.3 g/kg/day of DKT for periods ranging from 3 months to 1 year. We objectively assessed their bowel function, sphincter function and rectal reservoir function by anorectal manometry and clinical scoring. RESULTS: In 10 children with severe chronic constipation, the clinical score after administration of DKT (7.2 +/- 0.8) improved significantly compared with that before administration of DKT (4.6 +/- 2.9) (p < 0.02). The threshold sensation volume and the maximum tolerable volume after administration of DKT significantly (p < 0.05; p < 0.01) decreased (128 +/- 63 ml vs. 69 +/- 18 ml; 229 +/- 99 ml vs. 144 +/- 47 ml), and rectal compliance after administration of DKT also significantly (p < 0.05) decreased (12.4 +/- 10.9 ml/cmH(2)O vs. 4.7 +/- 3.9 ml/cmH(2)O). CONCLUSION: The present study demonstrated that DKT had a favorable clinical effect on severe constipation in children, and anorectal manometry showed an improvement in their rectal reservoir functions. It appears that the results were secondary to DKT-stimulated peristalsis of the intestine, which promoted regular bowel habits.  相似文献   
3.
To elucidate the frequency of mutations of the β/A4 amyloid protein precursor (APP) gene in early-onset Alzheimer disease, we designed a mismatched PCR-RFLP that can identify all kinds of missense mutations at codon 717 in addition to the seven kinds of known mutations at exon 17. When we screened mutations at exon 17 utilizing this method and the double missense mutations at exon 16 of the APP gene by PCR-RFLP, no cases revealed mutations of the APP gene among 13 familial and 54 sporadic cases, except one family (OS-1) that had previously been reported and used as a positive control of APP717(Val → Ile). Our results support the hypothesis that mutations in the APP gene are not major causes in early-onset Alzheimer disease.  相似文献   
4.
Several Caucasian studies and one Japanese study have observed associations between human leukocyte antigen (HLA) class I specificities, including A24 (9) and A26 (10) and schizophrenia. Most of those studies were conducted in 1970s and early 1980s, when the typing technique of HLA was not adequately reliable. Also, an operational diagnostic system was not employed in many of the studies. The present study investigated frequencies of HLA-A specificities in schizophrenia patients (ICD-10 and DSM-III-R, n=98) and sex-matched healthy controls (n=392) from population in the southwestern part of Japan. HLA-B and -C specificities were studied in addition. Frequencies of subjects possessing A24 and A26 were not different between the patients and controls (54% and 24% in the patients and 62% and 24% in the controls, respectively). No significant difference was found in frequencies of other class I (A, B, and C) specificities between the patients and the controls. Thus, the present study provided no evidence for an association between the HLA class I specificities, including A24, A26, and others, and schizophrenia in the Japanese population.  相似文献   
5.
Dietary antioxidants may attenuate oxidative damage from strenuous exercise in various tissues. Beneficial effects of the antioxidant astaxanthin have been demonstrated in vitro, but not yet in vivo. We investigated the effect of dietary supplementation with astaxanthin on oxidative damage induced by strenuous exercise in mouse gastrocnemius and heart. C57BL/6 mice (7 weeks old) were divided into groups: rested control, intense exercise, and exercise with astaxanthin supplementation. After 3 weeks of exercise acclimation, both exercise groups ran on a treadmill at 28 m/min until exhaustion. Exercise-increased 4-hydroxy-2-nonenal-modified protein and 8-hydroxy-2'-deoxyguanosine in gastrocnemius and heart were blunted in the astaxanthin group. Increases in plasma creatine kinase activity, and in myeloperoxidase activity in gastrocnemius and heart, also were lessened by astaxanthin. Astaxanthin showed accumulation in gastrocnemius and heart from the 3 week supplementation. Astaxanthin can attenuate exercise-induced damage in mouse skeletal muscle and heart, including an associated neutrophil infiltration that induces further damage.  相似文献   
6.
7.
Glial cell line-derived neurotrophic factor (GDNF) is a member of the transforming growth factor beta superfamily and acts as a neurotrophic factor for the nigrostriatal dopaminergic system. GDNF at a dose of 100 micrograms was injected stereotactically into the striatum of Sprague-Dawley rats that had been treated with intrastriatal 6-hydroxydopamine (6-OHDA) injection four weeks earlier. Immunocytochemical and behavioral analyses showed significant recovery of the nigrostriatal dopaminergic system after a single GDNF injection or continuous GDNF injection. Immunocytochemical and behavioral study showed that there was no significant difference between the results obtained from the two different injection methods. This result demonstrates the potential usefulness of GDNF for the treatment of Parkinson's disease.  相似文献   
8.
9.
Fixed drug eruption is a common cutaneous adverse reaction in young patients with a characteristic clinical appearance. However, the diagnosis and identification of the substance may be difficult if food or food additives provoke the fixed eruption. A 26‐year‐old man had a history of two episodes of cutaneous erythema with residual pigmentation. Close examination of the history including his diet in addition to an oral challenge test and patch testing led to the diagnosis of fixed eruption secondary to quinine in tonic water. We examined for the presence of quinine in commercially available brands of tonic water using ultraviolet A and irradiation and high‐performance liquid chromatography. Both Schweppes and CANADA DRY brands of tonic water emitted fluorescent light upon ultraviolet A irradiation, and contained quinine at concentrations of 67.9 and 61.3 mg/L, respectively. Quinine contained in some tonic waters may trigger fixed eruption.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号