全文获取类型
收费全文 | 2095篇 |
免费 | 85篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 42篇 |
妇产科学 | 80篇 |
基础医学 | 295篇 |
口腔科学 | 89篇 |
临床医学 | 194篇 |
内科学 | 411篇 |
皮肤病学 | 46篇 |
神经病学 | 132篇 |
特种医学 | 129篇 |
外科学 | 217篇 |
综合类 | 20篇 |
一般理论 | 1篇 |
预防医学 | 112篇 |
眼科学 | 42篇 |
药学 | 125篇 |
中国医学 | 2篇 |
肿瘤学 | 237篇 |
出版年
2023年 | 8篇 |
2022年 | 12篇 |
2021年 | 23篇 |
2020年 | 15篇 |
2019年 | 32篇 |
2018年 | 32篇 |
2017年 | 27篇 |
2016年 | 40篇 |
2015年 | 35篇 |
2014年 | 66篇 |
2013年 | 109篇 |
2012年 | 107篇 |
2011年 | 137篇 |
2010年 | 80篇 |
2009年 | 74篇 |
2008年 | 139篇 |
2007年 | 122篇 |
2006年 | 128篇 |
2005年 | 151篇 |
2004年 | 145篇 |
2003年 | 118篇 |
2002年 | 116篇 |
2001年 | 33篇 |
2000年 | 19篇 |
1999年 | 38篇 |
1998年 | 24篇 |
1997年 | 32篇 |
1996年 | 20篇 |
1995年 | 14篇 |
1994年 | 12篇 |
1993年 | 18篇 |
1992年 | 18篇 |
1991年 | 15篇 |
1990年 | 20篇 |
1989年 | 13篇 |
1988年 | 4篇 |
1987年 | 11篇 |
1986年 | 15篇 |
1985年 | 17篇 |
1984年 | 18篇 |
1983年 | 13篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1979年 | 5篇 |
1978年 | 11篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1975年 | 9篇 |
1974年 | 6篇 |
1973年 | 6篇 |
排序方式: 共有2184条查询结果,搜索用时 15 毫秒
61.
Al-Nawas B Brägger U Meijer HJ Naert I Persson R Perucchi A Quirynen M Raghoebar GM Reichert TE Romeo E Santing HJ Schimmel M Storelli S Bruggenkate CT Vandekerckhove B Wagner W Wismeijer D Müller F 《Clinical implant dentistry and related research》2012,14(6):896-904
Background: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two‐implant overdenture has been recommended as the standard of care. The use of small‐diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. Purpose: This randomized, controlled, double‐blind, multicenter study investigated in a split‐mouth model whether small‐diameter implants made from Titanium‐13Zirconium alloy (TiZr, Roxolid?) perform at least as well as Titanium Grade IV implants. Methods and Materials: Patients with an edentulous mandible received one TiZr and one Ti Grade IV small‐diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double‐blinded. Outcome measures included change in radiological peri‐implant bone level from surgery to 12 months post‐insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary). Results: Of 91 treated patients, 87 were available for the 12‐month follow‐up. Peri‐implant bone level change (?0.3 ± 0.5 mm vs ?0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices. Conclusion: This study confirms that TiZr small‐diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations. 相似文献
62.
Annick.F.L. Bogaerts Roland Devlieger Erik Nuyts Ingrid Witters Wilfried Gyselaers Isabelle Guelinckx Bea R.H. Van den Bergh 《Obesity facts》2013,6(2):152-164
BackgroundThe psychological health in obese women during pregnancy has been poorly studied.ObjectiveTo compare levels of anxiety and depressed mood during pregnancy in obese versus normal-weight women.Methods63 obese pregnant women and 156 normal-weight controls were included prospectively before 15 weeks of gestation. Levels of state and trait anxiety and depressed mood were measured during the first, second and third trimester of pregnancy. A linear mixed-effect model with repeated measures was used to evaluate group differences.ResultsThe levels of state anxiety significantly increased from trimester 1 to trimester 3 in obese pregnant women (beta = 3.70; p = 0.007), while this parameter remained constant throughout pregnancy in normal-weight women. Levels of trait anxiety and depressed mood significantly decreased from trimester 1 to trimester 2 in controls, but not in obese pregnant women. Variables such as maternal education, ethnicity, marital state, psychological history and miscarriages, parity and smoking behaviour had significant effects on anxiety and/or depressed moods during pregnancy. Obese pregnant women show higher levels of anxiety and depressive symptomatology compared to normal-weight pregnant women.ConclusionInterventional programmes aiming at preventing the deleterious influence of maternal obesity on perinatal outcomes should include a psycho-educational program specifically tailored to this high-risk group.Key Words: Obesity, Pregnancy, Body mass index, Anxiety, Depressed mood, Psychological aspects, Obesity management 相似文献
63.
Wilfried Pott ?zgür Albayrak Anke Hinney Johannes Hebebrand Ursula Pauli-Pott 《Obesity facts》2013,6(1):109-115
ObjectiveRecent case reports suggest a link between reduced melanocortinergic tone and both obesity and attention deficit / hyperactivity disorder (ADHD). We present the case of a 13-year-old, male, obese MC4R mutation carrier with ADHD.Case ReportThe boy carries a heterozygous mutation in the melanocortin 4 receptor gene (MC4R; Met281Val), that leads to a reduced receptor function. Dominant mutations of this type represent major gene effects for obesity. He participated in a lifestyle intervention program for obesity and received treatment with the selective norepinephrine re-uptake inhibitor atomoxetine for 31 months. The boy markedly reduced his BMI from 47.2 to 29.6 kg/m².ConclusionAtomoxetine proved to efficiently reduce weight in a severely obese MC4R mutation carrier with ADHD. We briefly discuss possible mechanisms for our observation, including evidence for the functional connectivity between melanocortinergic, dopaminergic, and norepinephrinergic brain circuitries.Key Words: Pharmacogenetics, Brain-derived neurotrophic factor, Weight loss, Appetite control, Methylphenidate 相似文献
64.
Wilfried Engelke Prof. Dr. Dr Alois Müller DDS Oscar A. Decco DDS María J. Rau Dipl. ‐Ing Andrea C. Cura Mara L. Ruscio Michael Knösel Priv. ‐Doz. Dr. 《Clinical implant dentistry and related research》2013,15(2):160-165
Aim: The study aims to provide objective data for the displacement of titanium screw implants in trabecular bone specimens. One hundred Semados implants (Bego, Bremen, Germany) were inserted in bovine type IV bone specimens. All implants had a diameter of 3.75 mm; 50 implants had a length of 8.5 mm and 50 implants had a length of 15 mm. Insertion torque was determined at intervals of 10, 20, and 30 Ncm. Implants were loaded horizontally with 10, 20, and 30 N for 2 seconds. An indicator strip was attached to the implant abutment to allow direct observation of implant movement relative to the bone surface. Horizontal displacement was assessed with an accuracy of measurement of 10 µm. Seven implants got lost by visible loosening. Degree of displacement was subject to evaluation with all others. Those implants showed a mean displacement of 59 µm for 10 N (n = 100), 173 µm for 20 N (n = 99), and 211 µm for 30 N (n = 93). The mean displacement of 15‐mm implants (16, 37, 51 µm) was significantly lower compared with 8.5‐mm implants (103, 311, 396 µm) corresponding to 10, 20, and 30 N as lateral loads. Conclusions: Displacement of screw implants in trabecular bone can be detected and visualized using commercially available endoscopes with a high magnification. A lateral load of 20 N indicates a mean displacement of over 100 µm and therefore results in a critical displacement. 相似文献
65.
66.
67.
68.
69.
Olivia Trummer Uwe Langsenlehner Sabine Krenn-Pilko Thomas R. Pieber Barbara Obermayer-Pietsch Armin Gerger Wilfried Renner Tanja Langsenlehner 《World journal of urology》2016,34(4):607-611
Purpose
Decreased vitamin D levels have been associated with prostate cancer, but it is unclear whether this association is causal. A functional single-nucleotide polymorphism (SNP) in the group-specific component (GC) gene (T > G, rs2282679) has been associated with 25-hydroxy (25-OH) vitamin D and 1.25 dihydroxy (1.25-OH2) vitamin D levels.Methods
To examine the hypothesized inverse relationship between vitamin D status and prostate cancer, we studied the association between this SNP and prostate cancer outcome in the prospective PROCAGENE study comprising 702 prostate cancer patients with a median follow-up of 82 months.Results
GC rs2282679 genotypes were not associated with biochemical recurrence [hazard ratios (HR) 0.91, 95 % confidence interval (CI) 0.73–1.12; p = 0.36], development of metastases (HR 1.20, 95 % CI 0.88–1.63; p = 0.25) or overall survival (HR 1.10; 95 % CI 0.84–1.43; p = 0.50).Conclusions
A causal role of vitamin D status, as reflected by GC rs2282679 genotype, in disease progression and mortality in prostate cancer patients is unlikely.70.
Wilfried Smidt Gisela Kammermeyer Susanna Roux Christiane Theisen Christian Weber 《Early child development and care》2018,188(10):1340-1353
The career success of preschool teachers has been discussed to be important because it can be a precondition for the ability to provide a high-quality preschool education. Consequently, the identification of factors that can help explain individual differences in career success is a crucial research issue. Previous research covering various occupations indicates that the Big Five, internal locus of control (LOC), and occupational self-efficacy are good predictors of objective and subjective career success. However, there is a research gap on this topic in preschool teachers. This study examined whether the Big Five, LOC, and occupational self-efficacy could predict the career success of 560 preschool teachers in Germany. After controlling for other predictors, internal LOC corresponded with higher objective career success, but neuroticism and conscientiousness corresponded with lower subjective career success. Occupational self-efficacy corresponded with higher subjective career success. The findings are discussed with respect to practical conclusions. 相似文献