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   866篇
  免费   37篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   18篇
妇产科学   7篇
基础医学   166篇
口腔科学   16篇
临床医学   42篇
内科学   185篇
皮肤病学   95篇
神经病学   62篇
特种医学   28篇
外科学   80篇
综合类   5篇
预防医学   21篇
眼科学   15篇
药学   89篇
中国医学   1篇
肿瘤学   74篇
  2023年   3篇
  2022年   10篇
  2021年   15篇
  2020年   12篇
  2019年   15篇
  2018年   13篇
  2017年   11篇
  2016年   14篇
  2015年   9篇
  2014年   22篇
  2013年   30篇
  2012年   51篇
  2011年   74篇
  2010年   27篇
  2009年   22篇
  2008年   43篇
  2007年   53篇
  2006年   54篇
  2005年   48篇
  2004年   44篇
  2003年   51篇
  2002年   54篇
  2001年   16篇
  2000年   15篇
  1999年   22篇
  1998年   15篇
  1997年   12篇
  1996年   4篇
  1995年   6篇
  1994年   7篇
  1993年   6篇
  1992年   9篇
  1991年   13篇
  1990年   9篇
  1989年   10篇
  1988年   10篇
  1987年   9篇
  1986年   7篇
  1985年   9篇
  1983年   3篇
  1982年   7篇
  1981年   8篇
  1980年   3篇
  1979年   2篇
  1978年   7篇
  1977年   4篇
  1976年   3篇
  1974年   3篇
  1972年   3篇
  1967年   2篇
排序方式: 共有905条查询结果,搜索用时 93 毫秒
1.
A technique for reducing the morbidity and mortality of pancreatoduodenectomy by using an omental flap to protect the anastomoses and splanchnic vessels exposed during dissection is described herein.  相似文献   
2.
Gambierol was isolated from Gambierdiscus toxicus, which causes ciguatera fish poisoning. The acute toxicological effects induced in mice by synthesized gambierol were studied. The lethal doses were about 80 μg/kg by i.p. and i.v., and 150 μg/kg by p.o. The main injury by this toxin was observed in the lung, and secondary in the heart, resulting in systemic congestion. Another toxic effect was seen in the stomach, inducing hypersecretion and ulceration. With survival from the severe stage during the initial 3 h, recovery was favorable, especially after 4 days. Additional effects were not evident during 1-week post-administration observation.  相似文献   
3.
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of autoantibodies and lupus nephritis. In the present study using New Zealand Black (NZB) x New Zealand White (NZW) F1 (NZBW F1) mice, we planned to investigate the effects of Toxoplasma gondii infection on the progress of lupus nephritis. Female NZBW F1 mice at the age of 2 months were perorally infected with T. gondii. The T. gondii infection reduced the number of mice developing proteinuria and immune complex deposits in their kidneys and prolonged their life span. A marked decrease in the levels of IgM and IgG anti-DNA antibodies, especially IgG2a and IgG3 subclasses, was observed in T. gondii-infected NZBW F1 mice at 9 months of age. The level of anti-HSP70 IgG autoantibody in the sera of NZBW F1 mice was significantly higher than that in control mice at 9 weeks after T. gondii infection. Moreover, NZBW F1 mice treated with anti-self heat shock protein 70 (HSP70) monoclonal antibody were substantially protected against the onset of glomerulonephritis. Further, down-regulation of intracellular expression of IFN-gamma and IL-10 was shown in spleen cells of T. gondii-infected NZBW F1 mice. This was consistent with the previous data indicating the involvement of Th1-type and Th2-type cytokines in the development of lupus-like nephritis. These results suggest that T. gondii infection is capable of preventing the development of autoimmune renal disorder in NZBW F1 mice.  相似文献   
4.
BACKGROUND: The essential role of Th cells and T cell cytokines in eosinophilic inflammation has been established. METHODS: To determine whether Th cells are sufficient for the development of airway eosinophilic inflammation, ovalbumin-reactive murine Th clones were established and infused into unprimed mice. RESULTS: Eosinophilic infiltration into the lung was induced upon antigen inhalation in parallel with the rise in bronchoalveolar lavage fluid (BALF) eosinophil peroxidase activity. Neither IgG, IgA, nor IgE antibodies were present in this model. Pathological examination showed swelling and desquamation of epithelial cells, mucous plugs, and goblet cell hyperplasia, all of which well resemble human asthma. Fluorescent probe labeled Th clones migrated into the lung prior to the eosinophil accumulation. Bronchial hyperresponsiveness (BHR) was clearly induced upon antigen inhalation. Anti-IL-5 monoclonal antibody abrogated the responses. Dexamethasone and cyclosporin A suppressed cytokine production by Th cells both in vitro and in vivo, BALF eosinophilia, and BHR. The number of eosinophils recovered in the BALF correlated with the intensity of BHR. CONCLUSION: The results clearly indicated that monoclonal Th cells are sufficient for the development of both airway eosinophilia and BHR. Agents capable of downregulating IL-5 production seem promising for the treatment of bronchial asthma.  相似文献   
5.
To assess the diagnostic value of myoglobin between elective surgery and acute arterial occlusion, serum and urine myoglobin (S-Mb, U-Mb) levels were measured before and for 7 consecutive days following arterial reconstructive surgery in 7 patients with abdominal aortic aneurysm or arteriosclerosis obliterans (elective surgery group), and in 20 patients with acute arterial occlusion due to embolism or thrombosis. They were divided into three groups based on symptoms and other features: mild, moderate, and severe groups. S-Mb and U-Mb levels were normal before surgery with a maximum of 389 ng/ml and 1,670 ng/ml after surgery in the elective surgery group, and 489 ng/ml and 11.7 ng/ml before surgery with a maximum of 703 ng/ml and 294 ng/ml after surgery in the mild cases. These two groups showed no complications after surgery. In the moderate group, high values of 2,420 ng/ml and 25,300 ng/ml were noted before surgery, and these values were elevated to 14,900 ng/ml and 175,000 ng/ml after surgery with complications of acute renal failure or peripheral nerve paresis. In the severe group, the values were 9,440 ng/ml and 260,000 ng/ml before surgery, and 160,000 ng/ml and 1,300,000 ng/ml after surgery, the elevation being associated with the severe clinical complication, myonephropathic metabolic syndrome (MNMS). All patients in this group died of MNMS. S-Mb and U-Mb levels before surgery proved useful for predicting the prognosis of patients with acute arterial occlusion. The findings obtained in our canine studies on the mechanism and treatment of MNMS suggest that alpha-tocopherol, a free radical scavenger, may be effective for treating dreadful complications such as MNMS.  相似文献   
6.
To investigate the role of the Toll-like receptor (TLR) family in host defense against Toxoplasma gondii, we infected TLR2-, TLR4- and MyD88-deficient mice with the avirulent cyst-forming Fukaya strain of T. gondii. All TLR2- and MyD88-deficient mice died within 8 days, whereas all TLR4-deficient and wild-type mice survived after i.p. infection with a high dose of T. gondii. Peritoneal macrophages from T. gondii-infected TLR2- and MyD88-deficient mice did not produce any detectable levels of NO. T. gondii loads in the brain tissues of TLR2- and MyD88-deficient mice were higher than in those of TLR4-deficient and wild-type mice. Furthermore, high levels of IFN-gamma and IL-12 were produced in peritoneal exudate cells (PEC) of TLR4-deficient and wild-type mice after infection, but low levels of cytokines were produced in PEC of TLR2- and MyD88-deficient mice. On the other hand, high levels of IL-4 and IL-10 were produced in PEC of TLR2- and MyD88-deficient mice after infection, but low levels of cytokines were produced in PEC of TLR4-deficient and wild-type mice. The most remarkable histological changes with infiltration of inflammatory cells were observed in lungs of TLR2-deficient mice infected with T. gondii, where severe interstitial pneumonia occurred and abundant T. gondii were found.  相似文献   
7.
Hepatitis C virus (HCV) has been linked to extrahepatic manifestations such as oral lichen planus (OLP). In addition, anticardiolipin antibodies (aCL) and cryoglobulin have been demonstrated in chronic hepatitis C. The aim of this study was to investigate these prevalences in patients with HCV-associated OLP. The prospective study investigated the role of these factors in 133 subjects: 28 with OLP-HCV(+) (group 1), 22 with OLP-HCV(-) (group 2), 33 without OLP-HCV(+) (group 3), and 50 healthy volunteers matched for age and sex served as control group (group 4). Levels of immunoglobulin G (IgG) and IgM aCL antibodies, and cryoglobulin in serum were evaluated by enzyme-linked immunosorbent assay. The prevalence of aCL in groups 1, 2, 3, and 4 were 32.1, 18, 36.3, and 8%, respectively. The positive rate of aCL was significantly higher in groups 1 and 3 than that in the control group (group 1; p=0.02 vs. the control group, group 3; p<0.01 vs. the control group). There were no significant differences in cryoglobulin among the groups. The findings of the present study showed a high prevalence of IgG and IgM aCL in the serum of patients with HCV infectious diseases. A positive factor for aCL was determined by age, sex, the presence of OLP, and HCV infection.  相似文献   
8.
Uchio E  Ono S  Ikezawa Z  Ohno S 《Allergy》1999,54(2):135-141
BACKGROUND: Vernal keratoconjunctivitis (VKC) is characterized by severe ocular allergic inflammation that may have a poor visual prognosis. Due to the high frequency of the presence of atopic dermatitis (AD) in VKC, most systemic parameters are dependent on the clinical severity of AD. METHODS: Serum levels of sICAM-1, sVCAM-1, and sIL-2R were measured by enzyme-linked immunoassay using samples from 30 VKC patients, 30 allergic conjunctivitis (AC) patients, and 20 normal subjects, to determine whether the concentrations of these molecules are elevated. RESULTS: Circulating sICAM-1 and sIL-2R levels were increased in patients with VKC with AD compared with those in VKC without AD, AC, and normal controls. Serum levels of sVCAM-1 in VKC patients with and without AD were significantly higher than those in controls. No significant difference was found in the levels of sVCAM-1 between patients with VKC with and without AD. In VKC patients with AD, the sIL-2R level correlated significantly with severity of AD, whereas no such correlation was found for sICAM-1 and sVCAM-1. CONCLUSIONS: These results suggest that serum sVCAM-1 can be used as a marker to differentiate VKC from nonproliferative ocular allergic diseases, and specific immunologic features of VKC may underlie the upregulation of serum sVCAM-1.  相似文献   
9.
BACKGROUND: Most children with anaphylaxis to measles, mumps, and rubella vaccines had shown sensitivity to bovine gelatin that was included in the vaccines. Recently, it was found that bovine type I collagen, which is the main content in the gelatin, is a major allergen in bovine gelatin allergy. Fish meat and skin also contain type I collagen. OBJECTIVE: The present study was designed to investigate IgE antibody to fish gelatin in children with fish allergy. METHODS: Serum samples were taken from patients in 3 groups: (1) 10 patients with fish allergy and specific IgE to fish meat; (2) two patients with allergies to both fish meat and bovine gelatin and specific IgE to fish meat and bovine gelatin; and (3) 15 patients with atopic dermatitis and specific IgE to fish meat. Various fish gelatins (type I collagen) were prepared from fish skin. IgE antibody to fish gelatin was analyzed by using ELISA and immunoblotting. RESULTS: Of 10 patients with fish allergy, 3 had specific IgE to fish gelatin. Of two patients with fish allergy and bovine gelatin allergy, all had specific IgE to fish gelatin. Of 15 patients with atopic dermatitis and specific IgE to fish meat, 5 had specific IgE to fish gelatin. Furthermore, IgE from pooled serum of the patients reacted with both the alpha1 and alpha2 chains of fish type I collagen in immunoblots. There is cross-reactivity among gelatins from various fishes, but there is little cross-reactivity between fish and bovine gelatins. CONCLUSION: Some fish-sensitive patients possessed IgE antibody to fish gelatin. Fish gelatin (type I collagen) might be an allergen in subjects with fish allergy.  相似文献   
10.
Atopic dermatitis (AD) has been clinically well-known to be frequently exacerbated by psychological and physiological stress. In this study, we examined effects of sedative odorant (modified valerian oil) inhalation on patients with AD. We investigated clinical scores, skin physiological parameters and psychological questionnaire (POMS) every 2 weeks. For first 2 weeks, we arranged non-inhalation period. Results for non-inhalation period were compared with these of 2- or 4-week inhalation. As results, sum of skin clinical scores significantly improved after odorant inhalation. Some patients improved for non-inhalation period, too. However, patients that had not improved for non-inhalation period significantly improved after odorant inhalation. Skin conductance and skin dryness/scaling score also improved after odorant inhalation without improving for non-inhalation period. Psychological parameter (POMS) also tended to improve after odorant inhalation. These results suggest that sedative odorants may be useful as a complementary therapy for AD through psychosomatic stress care.  相似文献   
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