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   115991篇
  免费   6909篇
  国内免费   948篇
耳鼻咽喉   1257篇
儿科学   3259篇
妇产科学   2827篇
基础医学   14979篇
口腔科学   2630篇
临床医学   9523篇
内科学   26992篇
皮肤病学   2435篇
神经病学   10731篇
特种医学   4461篇
外国民族医学   23篇
外科学   16858篇
综合类   1701篇
一般理论   52篇
预防医学   6184篇
眼科学   1791篇
药学   8783篇
  3篇
中国医学   542篇
肿瘤学   8817篇
  2023年   569篇
  2022年   1302篇
  2021年   2332篇
  2020年   1496篇
  2019年   2100篇
  2018年   2592篇
  2017年   2009篇
  2016年   2178篇
  2015年   2489篇
  2014年   3251篇
  2013年   4727篇
  2012年   6548篇
  2011年   6694篇
  2010年   4269篇
  2009年   3735篇
  2008年   5980篇
  2007年   6089篇
  2006年   5717篇
  2005年   5560篇
  2004年   5750篇
  2003年   5476篇
  2002年   5449篇
  2001年   3829篇
  2000年   3745篇
  1999年   3083篇
  1998年   1304篇
  1997年   1055篇
  1996年   948篇
  1995年   948篇
  1994年   818篇
  1993年   787篇
  1992年   1851篇
  1991年   1815篇
  1990年   1569篇
  1989年   1482篇
  1988年   1367篇
  1987年   1214篇
  1986年   1213篇
  1985年   1080篇
  1984年   819篇
  1983年   732篇
  1982年   500篇
  1981年   408篇
  1979年   591篇
  1978年   431篇
  1975年   450篇
  1974年   500篇
  1973年   480篇
  1972年   437篇
  1971年   403篇
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
101.
102.
Neurological Sciences - The diagnostic pathway in a patient with vertigo starts with the accurate evaluation of medical history followed by a general physical and neurological examination. This...  相似文献   
103.
We determined morphine plasma concentrations in 6 cancer patients before and with administration of diclofenac for 5 days. The non-steroidal anti-inflammatory drug does not modify morphine bioavailability. This observation suggests that diclofenac can be used in association with morphine during cancer pain treatment, without increasing the risk of overdosage or side effects of the opiate.  相似文献   
104.
Constituents of Fagaceae (Cupuliferae), XIX: Triterpene Saponins and Acylated Flavonoids from Quercus robur L. var. stenocarpa Beck. In addition to four known glycosides from leaves of Quercus robur L. var. stenocarpa Beck. a new triterpene saponin has been isolted and identified as 28-β-d-glucopyranosyl ester of the 2α,3β,19α-trihydroxy-olean-12-ene-24,28-dioic acid ( I ).  相似文献   
105.
BACKGROUND: Wounds too extensive to permit primary repair by suturing can be closed using a skin graft or skin flap and the choice of method depends on a series of factors. Practice and personal experience play a role, as well as the characteristics of the lesion and its site. Each case poses special problems, so it is not possible to establish firm rules. OBJECTIVE: To present a surgical technique for the closure of a circular defect located on the dorsum of the foot, which resulted from the extirpation of a melanoma by surgery. METHODS: In this case we used a mixed procedure consisting of skin flaps and a double full-thickness skin graft. For this operation we used dog-ears resulting from the circular exeresis performed for the extirpation of the tumour. RESULTS: The reconstructive results were good and there were no postoperative complications. CONCLUSIONS: We consider this procedure particularly suitable for certain anatomical sites, such as the dorsum of the foot, where the skin is less elastic and thinner; and for patients who are not willing to accept skin removal from other sites or for flaps to be made with more invasive operations and more constructed scars.  相似文献   
106.
107.
OBJECTIVE: Very few studies have examined post-operative morbidity after resection of oesophageal carcinoma, especially in patients treated with induction chemo- and radiotherapy for locally advanced stages. This study assessed the effects of induction chemoradiotherapy on post-operative course after resection of locally advanced oesophageal carcinoma (cT3-4 + cM1lymph). METHODS: Induction therapy consisted of 5-fluorouracil days 1-5 and days 21-25, cisplatin day 1 + day 21 and concomitant radiotherapy 18-20 fractions of 2Gy (total dose 36-40Gy). Induction chemoradiotherapy was completed in 109 patients. Surgery was performed in 90 patients (operability: 90/109 = 83%): 85 patients underwent resection with curative intent (resectability: 85/109 = 78%), bypass operation was performed in five patients. Nineteen patients could not be operated on. Results were compared to a matched group of pT3M1LYM/pT4 patients (n = 86) who underwent primary surgery in the same period. RESULTS: Resection was complete (R0) in 68 patients (68/90 = 76%). Mean duration of surgery was 428 min (range: 240-690). Peroperative complications were haemorrhage in three patients (3/90 = 3.3%), tracheobronchial perforation in three patients (3/90 = 3.3%). Median total hospital stay was 20.5 days (range: 8-355). Mean duration of intubation was 7 days (range: 1-190); 67 patients (67/90 = 74.4%) were intubated for less than 24 h. Non-tumour related hospital mortality after resection was 8.3% (7/84 patients). Mortality after two-field lymphadenectomy was 5.2 versus 11.7% after three-field lymphadenectomy. After primary surgery (n = 86) overall mortality was 2.3% (P = 0.015) and nil after two- and three-field lymphadenectomy (P = 0.011). Medical morbidity consisted of pneumonia in 43 patients (43/90 = 48%), atelectasis in ten patients (10/90 = 11%), dysrhythmia in 21 patients (21/90 = 23%), sepsis in 11 patients (11/90 = 12%) and adult respiratory distress syndrome in ten patients (10/90 = 11%). Surgical morbidity included pleural effusion in 16 patients (16/90 = 18%), tracheal fistula in two patients (2/90 = 2%), chylothorax in two patients (2/90 = 2%) and acute pancreatitis in one patient (1/90 = 1%). Ten patients (10/90 = 11%) had a radiologically confirmed anastomotic leak; however only in four out of them with clinical manifestation; treatment was conservative in all four patients. Major morbidity occurred in 27 patients (27/90 = 30%). Overall rate of morbidity was significantly higher after three-field lymphadenectomy (85%) as compared to two-field lymphadenectomy (68.7%; P = 0.023). CONCLUSIONS: Chemoradiotherapy followed by resection of cT3-4 +/- cM1lymph oesophageal carcinoma is feasible with acceptable mortality. Mortality, however, seems to be significantly higher when compared to a group of pT3M1LYM/pT4 patients who underwent primary surgery (8.3 versus 2.3%; P = 0.015) in the same period in our department.  相似文献   
108.
6-Hydroxy-N-methyl-N-(2-[4-phenylphenyl] ethyl)-1,2,3,4-tetrahydro-1- napthalene methanamine (A60586), a new non-azole inhibitor of ergosterol biosynthesis in Candida albicans ATCC62376 has been identified. In whole cells A60586 produced a dose related reduction of [14C]acetate incorporation into ergosterol and a concurrent increase in the radiolabelling of 4,4-dimethylated sterols. Similar observations were made with [14C]mevalonic acid lactone labelled cell free extracts. The IC50s for inhibition of ergosterol in the whole cell and cell free systems were 22 microM (10 mg/L) and 7.8 microM (3.5 mg/L), respectively. Analysis by gas chromatography of sterols from cells previously incubated at 37 degrees C for 24 h with A60586 (200 mg/L) confirmed the presence of lanosterol and 14 alpha-methyl fecosterol. These data indicate that A60586, inhibits the demethylation of the C-14 methyl group of lanosterol. The MIC of A60586 for several candida strains ranged from 12.5 to 50 mg/L, and against Cryptococcus albidus and Aspergillus niger ranged from 50 to 100 mg/L. The best in-vitro activity of A60586 was against Torulopsis glabrata (MIC range = 3.12 to 50 mg/L). The membrane permeabilizing effect of this compound (50% leakage of [14C]aminoisobutyric acid at 70 mg/L A60586) may have contributed to its in-vitro antifungal activity.  相似文献   
109.
OBJECTIVE: Test the ability of glutathione monoethyl ester (GSH(e)) to protect auditory hair cells against the ototoxic effects of 4-hydroxy-2,3-nonenal (HNE). STUDY DESIGN AND SETTING: Organ of Corti explants were either untreated or treated with one of a series of four concentrations of GSH(e) for one day, then exposed to HNE. Counts of FITC-phalloidin-labeled hair cells determined both HNE ototoxicity and GSH(e) otoprotection. RESULTS: HNE was toxic to hair cells at physiologically relevant levels, eg, 400 muM, and GSH(e) provided a significant level of protection against HNE ototoxicity (P < 0.05) at all levels tested, ie, 1.16 to 9.3 mM. CONCLUSION: GSH(e) protects auditory hair cells from damage and loss initiated by a naturally occurring ototoxic molecule, ie, HNE (a by-product of oxidative stress). SIGNIFICANCE: Treatment with GSH(e) may be an effective therapy to protect the cochlea against the adverse effects of traumas (eg, electrode insertion) that generate oxidative stress.  相似文献   
110.
Our aim was to develop and validate a new method to assess objectively and quantitatively the morphology of the nostrils after nasal or nasolabial surgery. We used digital analysis using specific mathematical algorithms to assess several geometric measurements, particularly of facial asymmetry, expressed in adimensional units. Forty-five patients with no facial anomalies (control group) were used initially to evaluate the method and to obtain variables for statistical reference. Thirty-five patients operated on for unilateral cleft lip and palate (cleft group) were then analysed and compared with the control group. Individual scores were obtained for each patient, computed, and correlated with those established by a lay panel. Statistical analysis showed good sensitivity and reliability (R>0.8).  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