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   1003篇
  免费   84篇
  国内免费   13篇
耳鼻咽喉   5篇
儿科学   20篇
妇产科学   32篇
基础医学   144篇
口腔科学   17篇
临床医学   72篇
内科学   264篇
皮肤病学   31篇
神经病学   64篇
特种医学   45篇
外科学   190篇
综合类   2篇
预防医学   64篇
眼科学   37篇
药学   35篇
中国医学   3篇
肿瘤学   75篇
  2023年   11篇
  2022年   44篇
  2021年   63篇
  2020年   41篇
  2019年   37篇
  2018年   46篇
  2017年   29篇
  2016年   41篇
  2015年   33篇
  2014年   30篇
  2013年   52篇
  2012年   71篇
  2011年   99篇
  2010年   55篇
  2009年   37篇
  2008年   38篇
  2007年   74篇
  2006年   66篇
  2005年   50篇
  2004年   58篇
  2003年   48篇
  2002年   51篇
  2001年   1篇
  2000年   1篇
  1999年   4篇
  1998年   1篇
  1996年   4篇
  1995年   2篇
  1990年   1篇
  1989年   1篇
  1986年   1篇
  1983年   1篇
  1981年   1篇
  1975年   3篇
  1974年   1篇
  1971年   1篇
  1969年   1篇
  1968年   1篇
  1967年   1篇
排序方式: 共有1100条查询结果,搜索用时 15 毫秒
11.
In Ontario, some court cases have involved attempts to sue social hosts for damage caused by the behaviour of drunken guests. Such legal actions give rise to the question of risks and responsibilities accruing to social hosts who serve alcohol. Using a sample of 1395 male and female adult residents of Ontario, the authors present self-report survey data concerning frequency of serving alcohol to guests, methods of handling guests who have too much to drink, prevention of drunk driving, service of alcohol to underage persons, and offering food and non-alcoholic drinks when serving alcohol at home. The results show high levels of intended safe practices overall, along with some areas for concern. Notably, about one-third of the total sample had had guests judged to be too drunk to drive home safely. A multivariate analysis confirmed significant differences associated with sex and age. The authors recommend the creation and evaluation of programmes to upgrade home-hosting skills as an adjunct to systemic alcohol control policies.  相似文献   
12.
13.
Several previous publications suggested that younger patients with brain metastases have longer survival than older patients. However, detailed studies of younger patient groups are scarce. Therefore, a multi-institutional analysis of younger patients with brain metastases was performed (defined as adults with age <50?years). Prognostic factors for survival were examined by uni- and multivariate analyses and compared to those obtained in patients with age ??50?years. Multivariate analysis of 106 patients (median age 44?years, range 23?C49?years) revealed three independent prognostic factors for survival: performance status, extracranial metastases and primary tumor control. Survival was significantly better in patients treated after the year 2000 (median 9.4?months) as compared to those treated before the year 2000 (median 5.1?months, p?=?0.04). This improvement appeared to be related to an increased use of surgery or radiosurgery (SRS) and decreasing numbers of patients with uncontrolled primary tumor. Irrespective of management approach, survival beyond 5?years was uncommon (actuarial rate 6?%; 17?% in patients treated with upfront surgery or SRS). In conclusion, more intense multidisciplinary approaches aiming at control both in the brain, extracranial metastatic sites, and primary tumor site might have contributed to gradual survival improvements in recent years. Nevertheless, further efforts are necessary to improve long-term survival.  相似文献   
14.
15.
Introduction:Mycoplasma pneumoniae (MP) infection in infants is usually overlooked and it might result in important complications if left untreated. MP-induced arthritis is probably the least common extrapulmonary manifestation and frequently leads to delays in the diagnosis.Patient concerns:We report the case of a 2-year-old female child admitted in our clinic for prolonged fever (onset 2 weeks before the admission), for which the general practitioner established the diagnosis of acute pharyngitis and recommended antibiotics. But the fever persisted and the patient was referred to a pediatrician.Diagnosis:The laboratory tests revealed leukocytosis with neutrophilia, elevated C-reactive protein and liver cytolysis. The blood and urine cultures, as well as the serological hepatitis B and C, toxoplasmosis, Epstein Barr virus, Rubella, Herpes virus, and cytomegalovirus were negative. The chest X-ray established the diagnosis of pneumonia. The fever persisted for approximately 2 weeks after admission. On the 2nd week of admission, the patient began to experience gait difficulties complaining of pain in the right hip and ankle. The cardiology and pneumology consults revealed no pathological findings. The evolution was favorable after the initiation of Levofloxacin and MP infection was detected as we suspected. Moreover, the ultrasound of the hip revealed a mild joint effusion, while the ankle joint appeared to be normal at ultrasound. Thus, we established the diagnosis of hip and ankle arthritis based on the clinical and ultrasound findings.Interventions:Levofloxacin by vein was continued for 5 days, replaced afterwards with clarithromycin orally for 2 weeks.Outcomes:The gait difficulties persisted for approximately 5 months from the initial diagnosis, and improved once the titer of immunoglobulin M anti-MP antibodies lowered considerably. After more than 8 months, the patient was completely asymptomatic and the immunoglobulin M anti-MP was close to the normal range.Conclusion:The awareness of MP-induced arthritis in children represents the cornerstone in preventing diagnostic delays and initiating the proper treatment.  相似文献   
16.
17.
Esophago-respiratory neoplastic fistulas present serious problems of management, mostly because of the severe status of the patient. The authors present the case of a 49-year-old patient with a malignant eso-tracheal fistula manifesting as mild dysphagia and dyspnoea. An endoscopic palliative treatment of the fistula was performed introducing a metallic coated stent into the esophagus. The multiple stent displacement required a definitive, very high positioning of the stent in the lower pharynx, with significant discomfort. Severe respiratory conditions regressed and the patient survived 6 months after the initial placement. The authors suggest endoscopic palliation with esophageal prosthesis as the therapeutic choice in those cases not amenable to surgery.  相似文献   
18.
Low rates of fetal and infant growth are associated with the metabolic syndrome and cardiovascular disease in later life. We investigated common genetic variation in the GH-CSH gene cluster on chromosome 17q23 encoding GH, placental lactogens [chorionic somatomammotropins (CSH)], and placental GH variant in relation to fetal and infant growth and phenotypic features of the metabolic syndrome in subjects aged 59-72 yr from Hertfordshire, UK. Allele groups T, D1, and D2 of a locus herein designated CSH1.01 were examined in relation to GH-CSH single nucleotide polymorphisms and to specific phenotypes. Average birth weights were similar for all genotype groups. Men with T alleles were significantly lighter at 1 yr of age, shorter as adults, and had higher blood pressures, fasting insulin (T/T 66% higher than D2/D2) and triglyceride concentrations, and insulin and glucose concentrations during a glucose tolerance test. Birth weight and 1-yr weight associations with metabolic syndrome traits were independent of the CSH1.01 effects. Common diversity in GH-CSH correlates with low 1-yr weight and with features of the metabolic syndrome in later life. GH-CSH genotype adds substantially to, but does not account for, the associations between low body weight, at birth and in infancy, and the metabolic syndrome.  相似文献   
19.
Lactoferrin (Lf) was shown to exhibit its antiviral activity at an early phase of viral infection and a mechanism whereby the protein interacts with host cell surface molecules has been suggested. In this study, human Lf (HLf) and seven HLf‐derived synthetic peptides (HLP) corresponding to the N‐terminal domain of the native protein (1–47 amino acids sequence) were assayed for their capacity to prevent hepatitis B virus (HBV) infection and replication using the HepaRG and HepG2.2.2.15 cell lines. Of the series tested, four peptides showed 40–75% inhibition of HBV infection in HepaRG cells, HLP1–23, containing the GRRRR cationic cluster, being the most potent. Interestingly, this cluster is one of the two glycosaminoglycan binding sites of the native HLf involved in its antiviral activity; however, the mechanism of the HLP1–23 action was different from that of the full‐length protein, the peptide inhibiting HBV infection when pre‐incubated with the virus, while no effect was observed on the target cells. It is suggested that the cationic cluster is sufficient for the peptide to interact stably with negatively charged residues on the virion envelope, while the absence of the second glycosaminoglycan binding site prevents its efficient attachment to the cells. In conclusion, this peptide may constitute a non‐toxic approach for potential clinical applications in inhibiting HBV entry by neutralizing the viral particles. J. Med. Virol. 85:780–788, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
20.
Cyprinid herpesvirus-3 (CyHV-3) induces the highly contagious koi herpesvirus disease (KHVD) and may result in significant economic losses to the ornamental and food-producing carp industry. Suspicion of KHVD is triggered by clinical signs and confirmed using laboratory techniques. The latter are labour- and time-consuming, require specialised equipment and trained personnel. For rapid, on-site detection of CyHV-3, a lateral flow device (LFD) was developed using two monoclonal antibodies directed towards the viral glycoprotein ORF65. The LFD was highly specific with analytical and diagnostic specificities of 100%. Analytical sensitivity ranged between 1.25 × 102 and 2.40 × 104 plaque forming units per ml for isolates originating from geographically distinct regions. In experimentally infected carp, CyHV-3 was detected as early as 4–5 days post infection. Diagnostic sensitivities of 52.6% and 72.2% relative to PCR were recorded, depending on the viral isolate used. When onset of mortality was taken as reference, diagnostic sensitivities increased to 67.0% and 93.3%. The diagnostic sensitivity for freshly found-dead animals was 100%, irrespective of the virus isolate used. Given the high specificity and ease-of-use for on-site detection of CyHV-3, the LFD was regarded fit for purpose as a first-line diagnostic tool for the identification of acute CyHV-3 infections in KHVD affected (koi) carp.  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