全文获取类型
收费全文 | 1844篇 |
免费 | 107篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 135篇 |
妇产科学 | 35篇 |
基础医学 | 135篇 |
口腔科学 | 66篇 |
临床医学 | 175篇 |
内科学 | 263篇 |
皮肤病学 | 35篇 |
神经病学 | 47篇 |
特种医学 | 176篇 |
外科学 | 177篇 |
综合类 | 243篇 |
预防医学 | 112篇 |
眼科学 | 69篇 |
药学 | 157篇 |
中国医学 | 77篇 |
肿瘤学 | 78篇 |
出版年
2024年 | 3篇 |
2023年 | 13篇 |
2022年 | 20篇 |
2021年 | 41篇 |
2020年 | 29篇 |
2019年 | 20篇 |
2018年 | 33篇 |
2017年 | 42篇 |
2016年 | 32篇 |
2015年 | 56篇 |
2014年 | 82篇 |
2013年 | 114篇 |
2012年 | 149篇 |
2011年 | 138篇 |
2010年 | 106篇 |
2009年 | 88篇 |
2008年 | 132篇 |
2007年 | 107篇 |
2006年 | 98篇 |
2005年 | 91篇 |
2004年 | 69篇 |
2003年 | 62篇 |
2002年 | 50篇 |
2001年 | 48篇 |
2000年 | 38篇 |
1999年 | 38篇 |
1998年 | 26篇 |
1997年 | 29篇 |
1996年 | 28篇 |
1995年 | 18篇 |
1994年 | 10篇 |
1993年 | 13篇 |
1992年 | 5篇 |
1991年 | 18篇 |
1990年 | 7篇 |
1989年 | 16篇 |
1988年 | 14篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 14篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 13篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 9篇 |
排序方式: 共有1996条查询结果,搜索用时 15 毫秒
91.
Titanium has become a material of great interest in prosthodontics in recent years because of its excellent biocompatibility, corrosion resistance and desirable physical and mechanical properties. In this study, we determined the influence of dental cements on the passivation of titanium. We developed experimental electrodes that associate titanium and dental cements. Polarization resistance of titanium electrodes has been determined for uncovered metal and electrodes covered with five different dental cements. Coverage with zinc eugenate led to more resistance to corrosion, but fluorinated composite such as glass-ionomer and zinc phosphate coverage increased the corrosion susceptibility. 相似文献
92.
窒息新生儿血清肝功能和心功能的变化及其临床意义 总被引:1,自引:0,他引:1
目的了解窒息新生儿血清肝功能和心功能的变化,有助于指导临床对窒息新生儿重要脏器损害的严重程度的判断,指导临床积极治疗。方法检测60例窒息新生儿(轻度窒息48例、重度窒息12例)的血清总胆红素(Tbil)、直接胆红素(Dbil)、谷丙转氨酶(ALT)、总胆汁酸(TBA)、肌酸激酶同工酶(CK-MB),并设40例正常新生儿作为对照。结果窒息后新生儿Tbil出现下降(P<0.05),并随着窒息程度加重下降愈明显(P<0.05);ALT、TBA、CK-MB出现升高(P<0.05),并随着窒息程度加重升高愈明显(P<0.05)。结论Tbil、ALT、TBA和CK-MB的变化反映肝功能和心功能损害情况,窒息时新生儿肝功能和心功能应予以保护,以减轻窒息对于新生儿重要脏器的损害。 相似文献
93.
大鼠注射重组腺病毒Ad-HGF后血清中抗腺病毒抗体的检测 总被引:2,自引:0,他引:2
目的观察大鼠重复给与携带肝细胞生长因子基因的重组腺病毒(recombinant adenovirus carrying hepatocyte growth factor gene,Ad-HGF)后,血清中抗腺病毒抗体的出现时间及消失规律。方法大鼠给与不同剂量的Ad-HGF共14次,利用病毒中和反应(细胞病变效应及绿色荧光方法)观察血清中抗腺病毒抗体。结果手术及正常对照组和实验组动物给药7次前血清处理的细胞均出现明显细胞病变效应及强荧光。之后各剂量组动物血清均对腺病毒有不同程度的中和作用,停药后13周到14周抗体水平很低或已不存在。同时观察到动物性别及给药剂量大小无差异。结论大鼠肌注Ad-HGF7次后,动物血清中可检测到抗腺病毒抗体,停药后13周或14周抗体基本消失,此结果对Ad-HGF的实际应用具有指导意义。 相似文献
94.
Irritable bowel syndrome (IBS) of theconstipation predominant type is a functionalintestinal disease characterized by abdominaldistress or pain, changed habit of defecationand abnormal defecation. Its pathogenesishas not been totally clarified yet. This re search is to explore the mechanism of pa tients with IBS of the constipation predomi nant type through the determination of ano rectal pressure via anus and better efficacyhas been obtained in the study by modify… 相似文献
95.
年轻妇女宫颈癌临床特征分析 总被引:1,自引:0,他引:1
目的分析35岁以下年轻妇女宫颈癌的发病趋势、临床特征变化等.方法对1998年-2003年我院收治的67例年轻宫颈癌患者(研究组)的临床资料进行回顾性分析,并随机选择同期有完整随访资料的82例年龄大于35岁的宫颈癌患者作对照组,分析两组资料间临床特点、病理及预后之间的差异.结果 1998年-2003年6年间年轻宫颈癌的构成比呈现逐渐上升趋势,分别为11.11%、13.63%、15.21%、17.28%、20.89%、23.58%;研究组以接触性出血为主要临床表现,占79.10%(53/67),与对照组的40.24%(33/82)比较有显著性差异(P<0.01);初诊时67例患者中30例(44.77%)曾在基层医院以宫颈炎、宫颈糜烂行对症治疗,12例(17.91%)以月经紊乱行调经治疗,1例术前诊断为子宫肌瘤,术后病检证实为宫颈癌;病理特点研究组内生型比率较对照组明显增高,二者比较有显著性差异;病理类型及组织类型上二者无明显差异,均以鳞癌为主(97.01%、95.21%),但术后淋巴病理检查显示对照组淋巴转移率高于研究组,有显著性差异.结论年轻宫颈癌患者的构成比呈现明显上升趋势,宫颈癌年轻化趋势明显;年轻宫颈癌临床症状较为隐匿,容易漏诊和误诊. 相似文献
96.
Dr Kaan Gündüz MD Dr Sibel Demirel MD Dr Ilhan Günalp MD Dr Burcu Pola MD 《Annals of Ophthalmology》2006,38(3):207-212
The choice of reconstructive technique for eyelid defects after malignant tumors was based on tumor location and defect size
after tumor excision. Treatments included direct closure for defects measuring less than 25%, Tenzel flap for defects measuring
25–50%, lid-sharing procedures for defects measuring more than 50%, skin grafts for tumors affecting the inner canthus advancement
flap for outer canthus tumors, and orbital exenteration for malignant tumors demonstrating orbital invasion.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacture
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which include
unlabeled, unapproved, or investigative products or diveces. 相似文献
97.
Apoptosis in the erectile tissues of diabetic and healthy rats 总被引:12,自引:0,他引:12
Alici B Gümüstas MK Ozkara H Akkus E Demirel G Yencilek F Hattat H 《BJU international》2000,85(3):326-329
OBJECTIVE: To compare the frequency of apoptosis in the erectile tissue of chronic diabetic and healthy rats. MATERIALS AND METHODS: Fourteen chronic diabetic and 10 healthy Sprague-Dawley rats were killed, their penises harvested and stored at -70 degrees C until staining and flow cytometric analysis for apoptosis. A cell suspension was obtained from the penile tissue by scraping the inside of the cavernosum with a scalpel and filtering through a mesh. Samples of the cell suspension (0.5 x 106 cells) were stained with Annexin V (an indicator of apoptosis) and propidium iodide (PI, which stains dead cells), incubated for 15 min at room temperature and analysed by flow cytometry. The DNA content was also analysed in each sample. RESULTS: In normal erectile tissue, a mean of 6.2% of cells were stained with Annexin V, while only 2.7% were stained with PI; DNA content analyses showed 7.5% were hypodiploid cells. In diabetic rats 19.5% of cells were stained with Annexin V and 5.2% with PI; 22.9% of cells were hypodiploid. CONCLUSION: The ratio of apoptotic cells in the erectile tissues of diabetic rats was significantly greater than in normal rats. The high rate of apoptosis in diabetic rats may play a role in the pathophysiology of erectile dysfunction. 相似文献
98.
Increased risk of leukaemia in patients with juvenile chronic arthritis treated with chlorambucil 总被引:2,自引:0,他引:2
MJ Kauppi HA Savolainen V-J Anttila HA Isomäki 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(2):248-250
Two cases of acute leukaemia have developed in a group of 77 patients treated with chlorambucil (Chl) because of severe juvenile chronic arthritis. The total follow-up from the beginning of Chl treatment in these patients was 560 years, indicating a highly increased risk of leukaemia. Despite favourable results, especially in patients with secondary amyloidosis, Chl should only be used in selected cases. 相似文献
99.
Prevalence and aetiology of neurological impairment in extremely low birthweight infants 总被引:2,自引:0,他引:2
J WAUGH MJ O'CALLAGHAN DI TUDEHOPE HA MOHAY YR BURNS PH GRAY YM ROGERS 《Journal of paediatrics and child health》1996,32(2):120-124
Objective : To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation Fi O2 >80% (OR 3.4; 95% Cl 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury. 相似文献
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation F
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury. 相似文献
100.
HA Heij RA Nievelstein I de Zwart BW Verbeeten J Valk A Vos 《Archives of disease in childhood》1996,74(5):441-444
OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients. 相似文献