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   38452篇
  免费   2081篇
  国内免费   57篇
耳鼻咽喉   400篇
儿科学   1180篇
妇产科学   824篇
基础医学   5911篇
口腔科学   283篇
临床医学   3434篇
内科学   9197篇
皮肤病学   882篇
神经病学   3603篇
特种医学   1128篇
外国民族医学   31篇
外科学   4687篇
综合类   81篇
一般理论   6篇
预防医学   2742篇
眼科学   626篇
药学   2557篇
中国医学   74篇
肿瘤学   2944篇
  2023年   202篇
  2022年   131篇
  2021年   524篇
  2020年   314篇
  2019年   587篇
  2018年   1082篇
  2017年   769篇
  2016年   732篇
  2015年   911篇
  2014年   923篇
  2013年   1491篇
  2012年   2622篇
  2011年   2585篇
  2010年   1220篇
  2009年   967篇
  2008年   2383篇
  2007年   2457篇
  2006年   2322篇
  2005年   2386篇
  2004年   2320篇
  2003年   2112篇
  2002年   2058篇
  2001年   1056篇
  2000年   1131篇
  1999年   896篇
  1998年   187篇
  1997年   131篇
  1996年   137篇
  1995年   133篇
  1994年   110篇
  1992年   522篇
  1991年   464篇
  1990年   461篇
  1989年   431篇
  1988年   390篇
  1987年   378篇
  1986年   339篇
  1985年   319篇
  1984年   232篇
  1983年   179篇
  1982年   104篇
  1979年   157篇
  1974年   118篇
  1973年   106篇
  1972年   109篇
  1971年   114篇
  1970年   106篇
  1969年   129篇
  1968年   110篇
  1967年   103篇
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
101.
Mg depletion is a type of Mg deficit due to a dysregulation of the Mg status. It cannot be corrected through nutritional supplementation only, but requires the most specific correction of the dysregulating mechanism. Among those, Biological Clock (BC) dysrhythmias are to be considered. The aim of this study is to analyze the clinical forms of Mg depletion with hypofunction of the Biological Clock (hBC). hBC may be due to either Primary disorders of BC [Suprachiasmatic Nuclei (SCN) and pineal gland (PG)] or Secondary with homeostatic response [reactive Photophobia (Pphi] to light neurostimulating effects [Nervous Hyper Excitability (NHE)]. The symptomatology is mainly diurnal and observed during fair weather (Spring,Summer). The elective marker of hBC is represented by a decrease in melatonin and in its metabolites in various fluids. The clinical forms of NHE due to Mg depletion with hBC are central and peripheral. The central forms associate anxiety, headaches and dyssomnia. The peripheral manifestations are neuromuscular: photosensitive epilepsia mainly. Three chronopathological forms of Mg depletion with hBC have been highlighted: 1. Headaches with Pphi: mainly migraine; 2. Sudden Infant Death Syndrome (SIDS); 3. Multiple Sclerosis (MS).- Headaches with Pphi, migraine particularly. These cephalalgias are diurnal with Pphi and are aggravated during the fair seasons (particularly during midnight sun-summer). Migraine is their typical form with its dishabituation to visual stimuli and its occipital cortex hyperexcitability. Comorbidity with anxiety is frequent. In 2/3 of the cases, it appears first.- SIDS might be linked to an impaired maturation of both photoendocrine system and brown adipose tissue. MS may be associated with primary disorders of BC Clinical forms of Mg depletion with hBC in MS present diurnal exacerbations and relapses during fair seasons. They have been underestimated because they disagree with the dogma of the < latitude gradient >, presently questioned. Comorbidities with anxiety and migraine are frequent.hBC may be treated by using darkness therapy with a balanced Mg status. Absolute light deprivation should only be used only in acute indications and is time-limited. Partial substitutive therapy and chromatotherapy have not been validated yet and are still uncertain.  相似文献   
102.
103.
BACKGROUND: In 1992 France set up a national cystic fibrosis observatory (Observatoire national de la mucoviscidose, ONM) to monitor the state of health of patients on an annual basis. Using the ONM data, this study estimates the main indicators for life expectancy and assesses the total number of cystic fibrosis patients. METHODS: The data for the years 1994 to 2003 are divided into 3-year periods. Life tables are drawn up for these periods, from which mean and median lengths of life are determined. Using the most recent life table, the number of births in 2003 and the incidence of the disease, the total population of patients can be estimated, assuming a stationary population. RESULTS: In 2001-2003, life expectancy at birth of patients registered with the ONM was 39.1 years and median length of life was 36.4 years. These results, substantially better than those of 1994-1996, are linked to improved conditions of patient inclusion in the ONM database, to improvements in their healthcare, but also to the limitations of the life tables. Based on the 2003 data, the total theoretical number of patients is 6490, and coverage by the ONM database is thus 63.2%. CONCLUSIONS: These provisional results demonstrate the need to convert the ONM observatory into a registry providing exhaustive coverage of all patients.  相似文献   
104.
The development of therapeutic options for rectal cancer strives to reach the ultimate goals of improved local control and overall survival. However, preserving continence, as well as genitourinary and sexual function, remains elusive in some patients. Loss of bowel control may be the most unsettling factor in terms of quality of life. Patients must be accurately informed about the surgery’s possible adverse effects, and surgeons must offer the best options (e.g. colostomy bag or sphincteroplasty) in order to minimize these complaints.  相似文献   
105.
OBJECTIVE: To evaluate the functional outcome in patients followed in the department of neurology of Dakar for stroke. MATERIALS AND METHOD: Prospective longitudinal observational study from August 2003 to May 2005 included inpatients or outpatients with stroke one month or less from entry confirmed by computed tomography scan. Patients were followed monthly for 12 months. At each visit, data on functional autonomy measured by the Barthel index and the treatments received were collected. RESULTS: One hundred and seventy patients aged 25 to 90 years (mean 61+/-13 years) were evaluated. The sex ratio was 0.68. A total of 64.7% of strokes involved ischemic cerebral vascular accidents and 35.3% hemorrhagic vascular accidents. Right hemiplegia was present in 55.9%, left hemiplegia in 42.9% and bilateral paresis in 1.2% of patients. A total of 28.8% of patients died between d0 and d30, 50.6% within one year. At entry, the Barthel score was greater than 60 in only 4.7% of patients. After one-year follow-up, 58.3% of the patients had a Barthel score greater than 60, 19.1% had a score between 20 and 40 and 22.6% a score between 40 and 60. Only 53.5% received rehabilitation care. The parameters significantly associated with a functional recovery were age less than 55 years (P<0.05), hemorrhagic vascular accident as opposed to ischemic vascular accident (P<0.05), and earlier rehabilitation care under qualified personnel (P<0.01). DISCUSSION: Our study shows an important rate of mortality during the first year following stroke and the rather young age of our population. The parameters associated with a better functional recovery are comparable to most of the data in the literature. The results of our study suggest that it is possible to improve functional prognosis after stroke by setting measures of prevention of the risk factors and rehabilitation in the early management of hemiplegia.  相似文献   
106.
107.
Staphylococcal necrotizing pneumonia producing the Panton Valentine leukotoxin (PVL) has been described for many years. The french reference center for staphylococcal toxaemia defined it with precision in 1999. A 10-year-old child, died in 36 hours from respiratory distress and shock. Staphylococcal pneumonia was suspected then confirmed: S. Aureus producing PVL was isolated in lung, blood and articulations.  相似文献   
108.
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed.  相似文献   
109.
Forty-four percent of the fibrillin-1 gene (FBN1) from 19 unrelated families with Marfan syndrome was screened for putative mutations by single strand conformational polymorphism (SSCP) analysis. Four novel mutations were identified and characterised in five people, three with classical Marfan syndrome (two from one family, and one from an unrelated family), one with a more severe phenotype, and one with neonatal Marfan syndrome. The base substitutions G2113A, G2132A, T3163G, and G3458A result in amino acid substitutions A705T, C711Y, C1055G, and C1152Y, respectively. C711Y, C1055G, and C1152Y lead to replacement of a cysteine by another amino acid; the latter two occur within epidermal growth factor-like motifs in exon 25 and 27, respectively. The A705T mutation occurs at exon 16 adjacent to the GT splice site. The A705T and C711Y mutations, at exon 16 and 17, respectively, are the first documented in the second transforming growth factor-beta 1 binding protein-like motif of FBN1.  相似文献   
110.
So far, laparoscopic approaches to kidney and adrenal have been limited because of their retroperitoneal location. We here report eight renal and adrenal endoscopic procedures performed in seven patients: two adrenalectomies for hyperaldosteronism, one adrenalectomy for isolated metastasis from an adenocarcinoma of the lung; two nephrectomies for end-stage infected hydronephrosis, two partial nephrectomies for small circumscribed lesions of the kidney, and one endoscopic resection for pain relief of a voluminous cyst at the kidney. The approach was transperitoneal in two cases and retroperitoneal in five cases using the retropneumoperitoneum insufflation technique. One patient was operated by a combined approach using the retro- and transperitoneal routes. All procedures were successfully completed endoscopically. The retroperitoneoscopic approach of the kidney is safe and does not interfere with the peritoneal organs. Its working space is tenuous, but allows a direct access on the kidney with good exposure of its pedicle. For adrenal surgery, the retroperitoneoscopic dissection is more difficult, because movements of instruments are often impaired by the closeness of the costal margin and the iliac crest. However, in case of difficulties we found it very convenient to switch from a retroperitoneal endoscopic approach to a combined coelioscopic and retroperitoneoscopic operation. Far from excluding each other, both approaches are complementary, particularly for difficult situations (i.e., previous peritoneal or retroperitoneal surgery).  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