全文获取类型
收费全文 | 17456篇 |
免费 | 821篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 178篇 |
儿科学 | 373篇 |
妇产科学 | 358篇 |
基础医学 | 1989篇 |
口腔科学 | 1454篇 |
临床医学 | 1169篇 |
内科学 | 4594篇 |
皮肤病学 | 437篇 |
神经病学 | 1414篇 |
特种医学 | 300篇 |
外科学 | 2518篇 |
综合类 | 90篇 |
一般理论 | 4篇 |
预防医学 | 1244篇 |
眼科学 | 373篇 |
药学 | 761篇 |
中国医学 | 81篇 |
肿瘤学 | 1035篇 |
出版年
2024年 | 32篇 |
2023年 | 132篇 |
2022年 | 277篇 |
2021年 | 584篇 |
2020年 | 335篇 |
2019年 | 530篇 |
2018年 | 616篇 |
2017年 | 408篇 |
2016年 | 423篇 |
2015年 | 524篇 |
2014年 | 739篇 |
2013年 | 898篇 |
2012年 | 1459篇 |
2011年 | 1585篇 |
2010年 | 900篇 |
2009年 | 733篇 |
2008年 | 1207篇 |
2007年 | 1370篇 |
2006年 | 1156篇 |
2005年 | 1015篇 |
2004年 | 895篇 |
2003年 | 743篇 |
2002年 | 757篇 |
2001年 | 93篇 |
2000年 | 67篇 |
1999年 | 75篇 |
1998年 | 114篇 |
1997年 | 96篇 |
1996年 | 82篇 |
1995年 | 53篇 |
1994年 | 56篇 |
1993年 | 46篇 |
1992年 | 29篇 |
1991年 | 26篇 |
1990年 | 24篇 |
1989年 | 12篇 |
1988年 | 17篇 |
1987年 | 15篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 27篇 |
1983年 | 19篇 |
1982年 | 12篇 |
1981年 | 24篇 |
1980年 | 20篇 |
1979年 | 11篇 |
1978年 | 10篇 |
1977年 | 18篇 |
1976年 | 14篇 |
1974年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Gomes-Filho JE de Moraes Costa MM Cintra LT Duarte PC Takamiya AS Lodi CS Bernabé PF 《Journal of endodontics》2011,37(2):250-254
Introduction
The aim of this study was to evaluate the rat alveolar bone response after the implantation of experimental light-cured mineral trioxide aggregate (MTA) or Angelus MTA (Angelus, Londrina, Paraná, Brazil) by histological and fluorescence analysis.Methods
Thirty Wistar Albino rats were divided into three groups. In the control group, empty polyethylene tubes were inserted into the rat alveolar sockets immediately after extraction. In the other groups, the tubes were filled with light-cured MTA or Angelus MTA. Five animals from each group were injected with calcein on day 7, alizarin on day 14, and oxytetracycline on day 21. On day 30, these animals were killed, and the right hemimaxillas were removed and histologically processed. Half of the maxillas were processed and stained with hematoxylin and eosin. The remaining maxillas were processed for fluorescence analysis and stained with Stevenel blue and alizarin red. New bone was histomorphometrically evaluated using a Merz grid.Results
The light-cured MTA presented a similar response when compared with Angelus MTA; it was characterized by a mild inflammatory response and complete bone healing. In the light-cured MTA group, the fluorescence areas were more evident at 21 days, showing an increase in bone formation. However, dystrophic mineralization was observed only with Angelus MTA.Conclusions
It was concluded that both materials present a similar inflammatory response and bone healing, but dystrophic mineralization was observed only with Angelus MTA. 相似文献62.
63.
Pereira FP Guskuma MH Luvizuto ER Faco EF Magro-Filho O Hochuli-Vieira E 《The Journal of craniofacial surgery》2011,22(5):1961-1963
The Ramsay Hunt syndrome is a rare disease caused by an infection of the geniculate ganglion by the varicella-zoster virus. The main clinical features of the syndrome are as follows: Bell palsy unilateral or bilateral, vesicular eruptions on the ears, ear pain, dizziness, preauricular swelling, tingling, tearing, loss of taste sensation, and nystagmus. We describe a 23-year-old white woman, who presented with facial paralysis on the left side of the face, pain, fever, ear pain, and swelling in the neck and auricular region on the left side. She received appropriate treatment with acyclovir, vitamin B complex, and CMP nucleus. After 30 days after presentation, the patient did not show any signs or symptoms of the syndrome. At follow-up at 1 year, she showed no relapse of the syndrome. 相似文献
64.
65.
Saliba FM Cardoso M Torres MF Teixeira AC Lourenço EJ Telles Dde M 《Journal of applied oral science : revista FOB》2011,19(1):63-67
Objectives
Previous studies that evaluated the torque needed for removing dental implant screws have not considered the manner of transfer of the occlusal loads in clinical settings. Instead, the torque used for removal was applied directly to the screw, and most of them omitted the possibility that the hexagon could limit the action of the occlusal load in the loosening of the screws. The present study proposes a method for evaluating the screw removal torque in an anti-rotational device independent way, creating an unscrewing load transfer to the entire assembly, not only to the screw.Material and methods
Twenty hexagonal abutments without the hexagon in their bases were fixed with a screw to 20 dental implants. They were divided into two groups: Group 1 used titanium screws and Group 2 used titanium screws covered with a solid lubricant. A torque of 32 Ncm was applied to the screw and then a custom-made wrench was used for rotating the abutment counterclockwise, to loosen the screw. A digital torque meter recorded the torque required to loosen the abutment.Results
There was a significant difference between the means of Group 1 (38.62±6.43 Ncm) and Group 2 (48.47±5.04 Ncm), with p=0.001.Conclusion
This methodology was effective in comparing unscrewing torque values of the implant-abutment junction even with a limited sample size. It confirmed a previously shown significant difference between two types of screws. 相似文献66.
Goiato MC de Carvalho Dekon SF de Faria Almeida DA Sánchez DM dos Santos DM Pellizzer EP 《The Journal of craniofacial surgery》2011,22(2):766-769
The matching of the aesthetic, functional, and psychosocial results of a facial deformity may produce devastating effects in its carriers, especially if the lesion is extensive or the treatment is aggressive. Because of this, the objective of the present article was to evaluate patient's satisfaction rating after surgical facial reconstruction or rehabilitation with oral and maxillofacial prosthesis, by means of reviewing the literature. 相似文献
67.
68.
Franco G. Marinello Eduardo M. TargaronaCarmen Balague María PocaJoan Mones Manuel Trias 《Cirugía espa?ola》2014
Introduction
Laparoscopic Heller myotomy has become the gold standard procedure for patients with achalasia. This study evaluates the clinical status, quality of life, and functional outcomes after laparoscopic Heller myotomy.Material and methods
We analyzed patients who underwent laparoscopic Heller myotomy with an associated anti-reflux procedure from October 1998 to December 2010. Before surgery, we administered a clinical questionnaire and as of 2002, we also evaluated quality of life using a specific questionnaire (GIQLI). In 2011, we performed a follow up for all available patients. We administered the same clinical questionnaire and quality of life test as before surgery and performed manometry and 24-hour pH monitoring. According to the length of follow up, patients were divided into 3 groups. Group 1 with a follow-up between 6 and 47 months; group 2 follow-up between 48 and 119 months, and group 3 with a follow-up of more than 120 months). Moreover, 27 patients had already been evaluated with this same protocol in 2003. Pre- and postoperative data were compared for the 3 groups and for patients who completed follow up in 2003 and 2011.Results
Ninety-five patients underwent laparoscopic Heller myotomy. Seventy-six (80%) were available for follow-up. Mean follow-up was 56 months (range 6-143). Global improvement in dysphagia was 89%. Total DeMeester score decreased in the 3 groups. GIQLI scores improved after surgery, reaching normal values. Manometric determinations showed normal LES pressures after myotomy in the 3 groups. Ten percent of overall 24-hour pH monitoring was abnormal. The group of patients followed up in 2003 and in 2011 showed no impairment in the variables studied in the long term.Conclusions
Long-term follow up of the laparoscopic approach to achalasia showed good results concerning clinical status and quality of life, with normal sphincteric pressures and a low incidence of gastroesophageal reflux. 相似文献69.
17alpha-hydroxylase deficiency : biochemical and molecular findings in two sisters and their family.
Maria S Perez Haydee Benencia Gustavo D Frechtel Eduardo O Esteban Maria Christina Gil Héctor M Targovnik Norma B Marquez 《Molecular diagnosis》2004,8(3):171-178
OBJECTIVE: To search for molecular changes in two Argentinian sisters with a clinical and biochemical diagnosis of 17alpha-hydroxylase deficiency. SUBJECTS: Both patients had 46 XX karyotype, with sexual infantilism, primary amenorrhea, and hypertension. Other member of the first degree family did not have this deficiency. HORMONAL RESULTS: The patients showed high levels of gonadotrophins and progesterone along with very low cortisol and androgen levels. Basal levels of corticosterone were very high, but aldosterone was normal. Both steroids had a high response after adrenocorticotropic hormone (ACTH) stimulation, with no changes in 17-hydroxyl progesterone and cortisol levels. Progesterone, corticosterone, and aldosterone decreased with the dexamethasone test, without modifications in 17-hydroxyl progesterone and cortisol levels. A corticosterone/aldosterone ratio was calculated from the results of the stimulation test; the ratios were similar in both patients. On administration of the ACTH test, both parents and one sister (S2) showed a marked response in corticosterone levels, their corticosterone/aldosterone ratios were also similar to each other and similar to the patients. MOLECULAR RESULTS: Molecular studies in the cytochrome P450 17 (CYP17) gene showed that exon 8 had a 4 bp duplication at codon 480 (CATC) in the two patients and their mother and in exon 1, a C to T transition at codon 96 was identified, changing CGG into TGG in the two patients, S2, and their father. CONCLUSIONS: Both patients were shown to be compound heterozygous, carrying different alleles in exon 1 and exon 8, inherited from their father and mother, respectively. The molecular results obtained on S2 confirmed the heterozygosity suggested by the stimulated hormonal test and corticosterone/aldosterone ratio. 相似文献
70.
Matos AB Oliveira DC Navarro RS de Eduardo CP Matson E 《Journal of clinical laser medicine & surgery》2000,18(5):253-257
OBJECTIVE: We evaluated the tensile bond strength of composite resin on enamel and dentine, treated with Nd:YAG laser before and after bonding procedures. BACKGROUND DATA: The use of laser radiation in dentistry is being developed day by day. One of the possible applications of dental lasers includes increasing the quality of self-etching bonding systems. METHODS: Forty-eight human teeth were used and separated into six groups: Group 1 (enamel control), Clearfil Liner Bond 2V (CLB 2V); group 2 (enamel), Nd:YAG + CLB 2V; group 3 (enamel), CLB 2V + Nd:YAG; group 4 (dentine control), CLB 2V; group 5 (dentine), Nd:YAG + CLB 2V; group 6 (dentine), CLB 2V + Nd:YAG. Tensile bond strength was performed. RESULTS: Enamel means (15,54) were lower than dentine means (20,38). Bond strength of laser before (15,73) was lower than laser after (20,65). Interaction results G1 x G3; G2 x G3; G4 x G1; G2 x G5 were statistically significant. Conclusions: Tensile bond strength of composites reached with self-etching adhesive systems were greater in dentine than in enamel. The best moment for application of Nd:YAG laser is after the use of adhesive system. Self-etching adhesive systems tested in this study can be used together with Nd:YAG laser without compromising to adhesion to dentine. 相似文献