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1.
Capillary malformation–arteriovenous malformation syndrome (CM‐AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM‐AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM‐AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM‐AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature.  相似文献   
2.
Infantile hemangiomas (IHs) are the most common benign tumor of infancy, characterized by a natural history of early proliferation in the first months of life to eventual involution during childhood, often with residual fibrofatty tissue. Once involution has been achieved, IHs do not typically recur. We present two cases of exogenous growth hormone therapy resulting in the recurrence of IHs in late childhood, supported by radiological, immunohistochemical, in vitro, and in vivo evidence.  相似文献   
3.
Age-standardized cancer incidence has decreased over the last years for many cancer sites in developed countries. Whether these trends led to narrowing or widening socioeconomic inequalities in cancer incidence is unknown. Using cancer registry data covering 48 million inhabitants in Germany, the ecological association between age-standardized total and site specific (colorectal, lung, prostate and breast) cancer incidence in 2007 to 2018 and a deprivation index on district level (aggregated to quintiles) was investigated. Incidence in the most and least deprived districts were compared using Poisson models. Average annual percentage changes (AAPCs) and differences in AAPCs between deprivation quintiles were assessed using Joinpoint regression analyses. Age-standardized incidence decreased strongly between 2007 and 2018 for total cancer and all cancer sites (except female lung cancer), irrespective of the level of deprivation. However, differences in the magnitude of trends across deprivation quintiles resulted in increasing inequalities over time for total cancer, colorectal and lung cancer. For total cancer, the incidence rate ratio between the most and least deprived quintile increased from 1.07 (95% confidence interval: 1.01-1.12) to 1.23 (1.12-1.32) in men and from 1.07 (1.01-1.13) to 1.20 (1.14-1.26) in women. Largest inequalities were observed for lung cancer with 82% (men) and 88% (women) higher incidence in the most vs the least deprived regions in 2018. The observed increase in inequalities in cancer incidence is in alignment with trends in inequalities in risk factor prevalence and partly utilization of screening. Intervention programs targeted at socioeconomically deprived and urban regions are highly needed.  相似文献   
4.
5.
??Abstracts?? Objective To study the T2* magnetic resonance imaging for evaluation of iron deposition of liver?? pancreas and heart in β- thalassemia major ??β-TM?? patients and the relationship of the serum ferritin with iron overload. Methods Measurement of hepatic?? pancreatic and cardiac MRI T2* was performed in 153 patients with β-TM from May 1?? 2010 to December 31?? 2010??The demographics and serum ferritin ??SF?? were collected. The rate of the iron overload in liver?? pancreas and heart was analyzed. The rates of combined pancreatic and cardiac iron overload in different hepatic iron overload groups were compared. Results According to MRI T2*?? there was serious hepatic iron overload in 85 cases?? moderate in 39?? mild in 21?? no iron overload in 8. Similarly?? there was pancreatic iron overload in 134?? no iron overload in 19. In terms of cardiac iron overload?? there was serious cardiac iron overload in 37 cases?? mild in 21?? no iron overload in 95. No correlation was found between hepatic?? pancreatic and cardiac MRI T2* and age or SF?? but hepatic MRI T2* correlated with pancreatic and cardiac MRI T2*??P = 0.000?? r = 0.529?? r = 0.369???? and pancreatic MRI T2* correlated with cardiac MRI T2* well ??P = 0.000?? r = 0.715??. As grade of hepatic iron overload increases?? the patients demonstrated higher rate of combination of pancreatic and cardiac iron overload simultaneously ??χ2 = 20.78??P = 0.000??.  相似文献   
6.
In root-treated anterior teeth a better aesthetic can be achieved by using translucent and tooth-coloured post and core restorations instead of traditional metal post systems. The aim of this in vitro study was to compare the fracture strength of tooth-coloured ceramic and fibre-reinforced posts as well as titanium posts with clinically proven gold alloy posts as a control. Two all-ceramic, one gold alloy and three combined post restoration systems (titanium and ceramic, respectively, fibre-reinforced posts with composite core) were each applied to upper incisors and after thermal cycling and mechanical loading (TCML) the fracture strength was determined. The variant providing the most reliable fracture strength values and the experimental fibre-reinforced composite (FRC) posts were - in combination with adhesively luted crowns - used to determine the fracture strength of the restoration after thermal cycling and mechanical loading. The median fracture strength of the luted posts and cores fluctuated between 114 and 546 N. Posts with composite cores demonstrate a higher fracture strength in comparison to the all-ceramic and gold alloy systems. Typical failure of metal systems was marked by loosening of the bonding and pulling out of the post in contrast to fracture of the ceramic posts. After the application of the crowns the ceramic system with composite core provided a fracture strength of 338 N and the FRC system a fracture strength of 228 N. Regarding fracture strength, the ceramic posts with composite cores are an alternative to commonly used gold posts and cores. A standardized technical manufacture of FRC posts and cores would provide better fracture strength results of this new dental material. Post and core restorations with tooth-coloured, translucent material offer an improved aesthetic especially in anterior restorations. Because of the high fracture strength prefabricated ceramic posts in combination with composite cores should prove their clinical applicability.  相似文献   
7.
OBJECTIVE: The aim of this study was to investigate the in-vitro marginal adaptation of all-ceramic class II inlays which were luted with conventional multi-stage pre-treatment cements and one new type of cement, which requires no conditioning. METHODS: The marginal adaptation of 56 all-ceramic inlays was determined with scanning electron microscopy and microleakage tests. The marginal integrity of each tooth was evaluated at cement-dentin and cement-enamel junctions, with regard to the transitions between tooth-cement and cement-inlay. The inlays were luted on human molars with two resin cements, one compomer, one resin modified glass-ionomer and one new resin cement in accordance with the manufacture's recommended pre-treatment. Light- and chemical-curing modifications were investigated. All tests were performed after thermal cycling and mechanical loading (TCML). RESULTS: For the resin cements and the new material the marginal integrity was higher than 90% before and after TCML. The marginal adaptation was between 55-80% for the resin modified glass-ionomer and lower than 20% for the compomer. The microleakage was lower than 20% for all cements, only the compomer showed values up to 100% penetration. SIGNIFICANCE: The difference in marginal integrity between the new universal resin cement without any tooth pre-treatment and conventional resin cements after total-etching, priming and bonding was not significant. Resin GIC may be used with restrictions and compomer cement should not be used with all-ceramic class II inlay restorations.  相似文献   
8.

Aim

The aim of this in vitro study was to compare the two-body wear resistance of substructure zirconia and veneering porcelain versus steatite and human enamel antagonists, respectively.

Materials and methods

Two-body wear tests were performed in a chewing simulator with steatite and enamel antagonists (enamel cusps). A pin-on-block design with a vertical load of 50 N for 1.2 × 105 cycles; (f = 1.6 Hz; lateral movement: 1 mm, mouth opening: 2 mm) was used for the wear test. For quantification of the wear resistance, wear tests were performed with standardized steatite spheres. Human enamel was used as a reference. Five zirconia ceramics and four veneering porcelains were investigated. One zirconia ceramic was tested with superficial glaze, which was applied after polishing or sandblasting, respectively. Surface roughness Ra (SP6, Perthen-Feinprüf, G) and wear depth were determined using a 3D-Profilometer (Laserscan 3D, Willytec, G). SEM (Quanta FEG 400, FEI, USA) pictures were used for evaluating wear performance of both, ceramics and antagonists.

Results

No wear was found for zirconia substructures. Veneering porcelain provided wear traces between 186.1 ± 33.2 μm and 232.9 ± 66.9 μm (steatite antagonist) and 90.6 ± 3.5 μm and 123.9 ± 50.7 μm (enamel). Wear of the steatite antagonists varied between 0.812 ± 0.256 mm2 and 1.360 ± 0.321 mm2 for zirconia and 1.708 ± 0.275 mm2 and 2.568 ± 0.827 mm2 for porcelain. Enamel generally showed wear, cracks or even fractures at the ridge, regardless whether opposed by zirconia or porcelain/glaze. Enamel was polished, when opposed to zirconia, or plowed, provoked and grinded, when opposed to porcelain/glaze.

Conclusion

The results of the wear test with steatite or enamel antagonists indicated no measurable wear on zirconia surfaces. Porcelain showed higher wear than zirconia, but comparable or lower wear than an enamel reference. Antagonistic wear against zirconia was found to be lower than wear against porcelain.  相似文献   
9.
The aim of this in vitro study was to compare the fracture resistance and marginal adaptation of all-ceramic incisor crowns with all-ceramic posts, glass-fibre-reinforced posts and titanium posts as well as a control without any post. Three groups of eight maxillary incisors were restored with an all-ceramic post, a fibre-reinforced composite (FRC) post, a titanium post and a further group was restored without posts. Composite cores were provided and all-ceramic crowns were adhesively luted. After artificial ageing, the fracture resistance of the restored teeth was determined. The marginal adaptation of the restorations at the interfaces between cement-tooth and cement-crown was evaluated with scanning electron microscopy using replica specimen before and after ageing. The restored teeth without posts [270N (235/335)] showed no significantly different fracture strength compared with teeth with the titanium system [340N (310/445)]. The all-ceramic posts [580N (425/820)] and the FRC posts [505N (500/610)] both provided a significant higher fracture resistance than the teeth without posts. Prior to ageing, all materials showed <5% separation at the margins cement-tooth or cement-crown ('marginal gap'). After ageing, the interfaces of all systems deteriorated to values between 6 and 14% marginal gap. The greatest marginal gap was found with the titanium system (14%) at the interface cement-crown and with the all-ceramic posts (12%) at the transition between cement-tooth. Regarding fracture resistance and the marginal adaptation, the all-ceramic and FRC posts may be considered as an alternative to the commonly used titanium post restorations.  相似文献   
10.
OBJECTIVES: This study compared the influence of different inner crown surfaces on the fracture resistance and marginal adaptation of adhesively fixed glass fibre-reinforced molar crowns. MATERIALS AND METHODS: Vectris/Targis crowns were constructed with an inner framework of glass fibres (directly on the tooth) or an inner veneering composite layer between the fibre-framework and the tooth-substance. Both groups were sandblasted inside using Al(2)O(3); 50 microm grain size (200 kPa, 20 s) and silane coated. A control group had the inner fibre framework, but was neither sandblasted nor silane coated. The crowns were adhesively cemented on extracted human teeth, and thermally cycled and mechanically loaded (TCML: 6000 x 5 degrees C/55 degrees C; 1.2 x 10(6) x 50 N, 1.66 Hz). The marginal adaptation before and after TCML was evaluated and the fracture resistance was investigated using a Zwick universal testing machine. RESULTS: After TCML the proportion of 'perfect margin' of the control group decreased significantly at the interface crown/cement. For the variations with an inner fibre framework or inner composite layer the marginal adaptation or fracture resistance did not decrease significantly after ageing. The fracture resistance values were control: 1509N+/-486; inner fibre framework: 1896N+/-342; inner composite layer: 1754N+/-340. CONCLUSIONS: In the case of the investigated fibre framework and veneering composite, the inner surface of glass fibre-reinforced molar crowns can be covered with a composite layer or with a glass fibre framework. Both methods achieve comparable high fracture strengths and reliable marginal adaptation.  相似文献   
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