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61.

Purpose

To review the 64-slice CTA (computed tomography angiography) appearance of anatomical variations in branching pattern of the arcus aorta, and to determine their prevalence in 1001 cases.

Materials and methods

1001 cases that underwent carotid CTA (performed by a 64-slice scanner) were included in the study.

Results

Seven types of aortic arch were found. In 853 cases (853/1001, 85.2 %) classical branching pattern of arcus aorta (three branches; TB, LCC, LS) was observed. Variations were present in 147 cases (147/1001, 14.7 %). One case (1/1001, 0.1 %) had right aortic arch. The most frequent variation was origination of LCC from TB (arch with 2 branches, TB with LCC and LS) which was observed in 78 cases (78/1001, 7.8 %). Origination of LV directly from the aortic arch (four branches; TB, LCC, LV, LS or TB, LCC, LS, LV) was observed in 51 cases (51/1001, 5.1 %). In two cases (2/1001, 0.2 %) truncus bicaroticus (3 branches; RS, common trunk for carotids, LS) was present. In seven cases (7/1001, 0.7 %) aortic arch had four branches in the order of RCC, RS, LCC and LS. In one case (1/1001, 0.1 %) left truncus brachiocephalicus (three branches; RS, RCC, LTB) was present. Seven cases (7/1001, 0.7 %) had aberrant RS (RCC, LCC, LS, RS).

Conclusion

Variations in branching pattern of arcus aorta are not rare and being aware of them before surgical and interventional procedures of this region is important. CTA can depict the anatomical features of the aortic arch and is valuable as a road map.  相似文献   
62.
Obesity‐induced insulin resistance and type 2 diabetes mellitus can ultimately result in various complications, including diabetic cardiomyopathy. In this case, cardiac dysfunction is characterized by metabolic disturbances such as impaired glucose oxidation and an increased reliance on fatty acid (FA) oxidation. Mitochondrial dysfunction has often been associated with the altered metabolic function in the diabetic heart, and may result from FA‐induced lipotoxicity and uncoupling of oxidative phosphorylation. In this review, we address the metabolic changes in the diabetic heart, focusing on the loss of metabolic flexibility and cardiac mitochondrial function. We consider the alterations observed in mitochondrial substrate utilization, bioenergetics and dynamics, and highlight new areas of research which may improve our understanding of the cause and effect of cardiac mitochondrial dysfunction in diabetes. Finally, we explore how lifestyle (nutrition and exercise) and pharmacological interventions can prevent and treat metabolic and mitochondrial dysfunction in diabetes.  相似文献   
63.
D‐A‐D‐type polymers are of high interest in the field of photovoltaics and electrochromism. In this study we report the synthesis and electrochemical properties of PPyBT along with its photophysical properties and photovoltaic performance. PPyBT is soluble in common organic solvents and both n‐ and p‐type dopable, which is a desired property for conjugated polymers. During electrochemistry studies, the onset potentials of the polymer were determined as +0.2 V for oxidation and ?1.4 V for reduction. Using these values, HOMO and LUMO energy levels were calculated. The photovoltaic properties of PPyBT were also studied. PL studies showed that there is a charge transfer between PPyBT (donor) and PCBM (acceptor).

  相似文献   

64.
Association of psoriasis vulgaris with HLA-C is not equally strong in different human populations. It has not yet been studied in Polish patients at DNA level, but only by serology that is inadequate for HLA-C. Therefore, we examined the distribution of HLA-C alleles by means of low resolution PCR-SSP in 102 Polish psoriatics and 123 healthy controls. We have found significantly higher representation of HLA-Cw*06 (odds ratio, 18.73; P(cor)<0.001) and significantly lower representation of HLA-Cw*07 (odds ratio, 0.41; P(cor)<0.038) in patients than in controls. Association of HLA-Cw*06 with psoriasis was even stronger in early age at onset (0-20 years) group: odds ratio, 77.71; P(cor)<0.001. Therefore, our population seems to belong to those with strong association of psoriasis with HLA-Cw*06.  相似文献   
65.
ObjectivesMesoporous fillers have been investigated for use in dental composites because of their potential for creating micromechanical filler/resin matrix interphase bonding. Such a micromechanical bonding could eliminate the need for the silane treatment of fillers for interfacial chemical bonding that is prone to hydrolysis in the oral environment. In the case of micromechanical bonding, dental polymer chains are threaded mechanically (like a “necklace”) through nanosized channels in the fillers.MethodsA combination of mesoporous silica, which was synthesized using the non-surfactant templating method, and nonporous spherical silica (500 nm) was used to prepare experimental dental composites. The porous silica used in this study contained interconnected pores and channels as opposed to porous fillers containing surface pores. The compressive strength, compressive modulus, flexural modulus, and flexural strength of these composites were evaluated.ResultsThe results showed that composites containing a combination of mesoporous and nonporous fillers have better mechanical properties than the composites having either of these fillers alone.SignificanceThe results showed that a combination of mesoporous and nonporous materials can be used to prepare stronger dental materials that may resist hydrolysis and wear.  相似文献   
66.

Purpose

To investigate whether accessory vein embolization (AVE) improves long-term performance of salvaged nonmaturing arteriovenous fistulae (AVFs).

Materials and Methods

This retrospective review included 72 patients who underwent percutaneous balloon angioplasty for salvage of nonmaturing AVFs between 2008 and 2014. AVE was performed on 32 patients between 2008 and 2011 (mean age, 59 y [range, 33–85 y]; men, n = 21; women, n = 11; upper arm, n = 17; forearm, n = 15), whereas the procedure was not performed on 40 patients after 2011 (mean age, 62 y [range, 28–85 y]; men, n = 26; women, n = 14; upper arm, n = 26; forearm, n = 14). Endpoints compared between groups included number of procedures required to achieve maturation, time to maturation, number of procedures required to maintain patency, and duration of primary and secondary patency after intervention.

Results

There was no statistically significant difference in number of procedures to achieve maturation (2.1 ± 1.4 vs 2.4 ± 1.2; P = .24) or time to maturation (26.1 d ± 56.2 vs 41.1 d ± 54.6; P = .072) between AVE and no embolization groups. Primary (P = .21) and secondary patency (P = .14) after intervention were not significantly different between groups. The number of procedures performed to maintain patency after maturation was significantly greater in the AVE group for patients with forearm AVFs (0.11 ± 0.098 vs 0.04 ± 0.064 per patient year; P = .039) but not for patients with upper arm AVFs.

Conclusions

AVE of AVFs after balloon angioplasty does not lead to significantly improved long-term outcomes. Percutaneous salvage of nonmaturing AVFs in the forearm without AVE resulted in a decreased number of interventions to maintain patency.  相似文献   
67.
Weight loss inhibits thyrotropic function and reduces metabolic rate, thereby contributing to weight regain. Under negative energy balance there is an increase in the hypothalamic expression of both neuropeptide Y (NPY) and agouti related peptide (AgRP), the endogenous antagonist of melanocortin 4 (MC4) receptors. Both NPY and MC4 receptor antagonism reduce thyrotropic function centrally, but it is not known whether these pathways operate by similar or distinct mechanisms. We compared the time-course of effects of acute or chronic intracerebroventricular (ICV) administration of NPY (1.2 nmol acute bolus, or 3.5 nmol/day for 6 days) or the MC4 receptor antagonist HS014 (1.5 nmol bolus, or 4.8 nmol/day) on plasma concentrations of thyroid stimulating hormone (TSH) or free thyroxine (T4) in male rats pair-fed with vehicle-infused controls. These doses equipotently induced hyperphagia in acute studies, reduced latency to feed, and increased white adipose tissue mass after 6 days of infusion. Acute central NPY but not HS014 administration significantly reduced plasma TSH concentrations within 30–60 min and plasma free T4 levels within 90–120 min. These inhibitory effects were sustained for up to 5–6 days of continuous NPY infusion. HS014 induced a transient decrease in plasma free T4 levels that was observed only after 1–2 days of continuous ICV infusion. While both NPY and HS014 significantly increased corticosteronemia within an hour after ICV injection, the effect of NPY was significantly more pronounced and was sustained for up to 4 days of administration. Both NPY and HS014 significantly decreased the brown adipose tissue protein levels of uncoupling protein-3. We conclude that central NPY and MC4 antagonism decrease thyrotropic function via partially distinct mechanisms with different time courses, possibly involving glucocorticoid effects of NPY. MC4 receptor antagonism increases adiposity via pathways independent of increased food intake or changes in circulating concentrations of TSH, free T4 or corticosterone.  相似文献   
68.
The aim of this clinical study was to test the efficacy of a light‐emitting diode (LED) light and a diode laser, when bleaching with sodium perborate. Thirty volunteers were selected to participate in the study. The patients were randomly divided into two groups. The initial colour of each tooth to be bleached was quantified with a spectrophotometer. In group A, sodium perborate and distilled water were mixed and placed into the pulp chamber, and the LED light was source applied. In group B, the same mixture was used, and the 810 nm diode laser was applied. The final colour of each tooth was quantified with the same spectrophotometer. Initial and final spectrophotometer values were recorded. Mann–Whitney U‐test and Wicoxon tests were used to test differences between both groups. Both devices successfully whitened the teeth. No statistical difference was found between the efficacy of the LED light and the diode laser.  相似文献   
69.
The aim of this study was to compare the root filling material that remained after retreatment of curved root canals with chloroform and Endosolv R as solvents. The evaluation employed micro‐computed tomography (CT) imaging. Thirty‐six extracted molar teeth with curved roots were selected. After preparation with ProTaper rotary instruments, the canals were filled with gutta‐percha and AH26 sealer. The teeth were randomly divided into three groups according to solvent used (n = 12) as follows: group 1: chloroform; group 2: Endosolv R; group 3: no solvent (negative control). ProTaper Universal Retreatment files were used to remove each root canal filling and then the self‐adjusting file was applied for two minutes. Preoperative and postoperative micro‐CT images were used to assess the percentage of residual filling material. The mean percentage of residual filling material was quantified. There were no statistically significant differences between the groups in terms of percentage volume of residual root canal filling.  相似文献   
70.
A major challenge in the cognitive training field is inducing broad, far‐transfer training effects. Thus far, little is known about the neural mechanisms underlying broad training effects. Here, we tested a set of competitive hypotheses regarding the role of brain integration versus segregation underlying the broad training effect. We retrospectively analyzed data from a randomized controlled trial comparing neurocognitive effects of vision‐based speed of processing training (VSOP) and an active control consisting of mental leisure activities (MLA) in older adults with MCI. We classified a subset of participants in the VSOP as learners, who showed improvement in executive function and episodic memory. The other participants in the VSOP (i.e., VSOP non‐learners) and a subset of participants in the MLA (i.e., MLA non‐learners) served as controls. Structural brain networks were constructed from diffusion tensor imaging. Clustering coefficients (CCs) and characteristic path lengths were computed as measures of segregation and integration, respectively. Learners showed significantly greater global CCs after intervention than controls. Nodal CCs were selectively enhanced in cingulate cortex, parietal regions, striatum, and thalamus. Among VSOP learners, those with more severe baseline neurodegeneration had greater improvement in segregation after training. Our findings suggest broad training effects are related to enhanced segregation in selective brain networks, providing insight into cognitive training related neuroplasticity.  相似文献   
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