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Temporomandibular disorders (TMD) are defined as clinical conditions that involve the masticatory muscles, temporomandibular joint (TMJ) or both. The aim of this study was to evaluate serum 17β‐oestradiol and progesterone levels in menstruating women affected by internal derangement of the TMJ. A total of 142 women (mean age 30·2 ± 6·7) who referred to medical diagnostic laboratory of Iranian Academic Centre for Education, Culture and Research (ACECR), Mashhad Branch, were enrolled during 2007 and 2008. Forty‐seven individuals had disc displacement with reduction (Group IIa) according to Research Diagnostic Criteria (RDC)/TMD Axis I diagnosis. Radioimmunoassay was used for the detection of serum 17β‐oestradiol and progesterone levels in all 142 subjects. The mean progesterone level was significantly higher in control group (11·6 ± 10·4 ng mL?1) compared to women with TMD (8·4 ± 6·8 ng mL?1, P = 0·03). No significant difference was found in two groups regarding 17β‐oestradiol level. Lower progesterone level in women with TMD can suggest the more important role of this hormone in the development of the disorder.  相似文献   
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Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface _lasmon). These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on) perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented.  相似文献   
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ObjectiveThe aims of this study were to evaluate the psychometric properties of Persian translation of the Yale Food Addiction Scale 2.0 (YFAS 2.0) as a widely accepted questionnaire for the first time and to establish a cut off score for Food Craving Questionnaire-Trait-reduced (FCQ-T-r). MethodsIn this cross-sectional study, 330 visitors of family physician clinics in Shiraz, a city located in south of Iran, were selected. The English version of YFAS 2.0 was translated into Persian and used in this study as well as the Persian version of FCQ-T-r. ResultsConfirmatory factor analysis of YFAS-2 confirmed one dimensional structure and factor loading in all eleven symptoms was above 0.4. Internal consistency for eleven symptoms was 0.813. Prevalence of food addiction in participants was 6.7% (22 participants). BMI and FCQ-T-r questionnaire score both were positively correlated with the number of food addiction symptoms but age was negatively correlated with the number of the symptoms. The ROC curve analysis showed the best suggested cut-off point for FCQ-T-r questionnaire to detect food addiction was 32.5. ConclusionThe present study confirmed validity and reliability of Persian version of YFAS-2. It is suggested that food addiction occurs in different level of food craving behavior in different food cultures or genetics.  相似文献   
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In addition to determining the lethal effects, identifying sublethal effects of a pesticide is crucial to understanding the total impact a pesticide may have on a pest population. We determined the sublethal effects the two pesticides, abamectin and pyridaben, have on the cyclamen mite, Phytonemus pallidus (Banks) (Acari: Tarsonemidae)—a major pest of strawberry. Demographic traits of the P. pallidus progeny (F1 generation) produced by parents (F0 generation) treated with a low lethal concentration (LC15) of abamectin and pyridaben were assessed using the age-stage, two-sex life table theory. The total longevity of the F1 generation (males = 10.78 days; female = 14.35 days) was the shortest in the progeny of the abamectin treated parents, differing significantly from the progeny of mites treated with pyridaben (males = 11.50 days, females = 15.63 days), and the control population (males = 13.50 days, females = 17.81 days). The intrinsic rates of increase (r) and the finite rates of increase (λ) of the progeny of abamectin (r = 0.0854 day−1, λ = 1.0891 day−1) and pyridaben (r = 0.0951 day−1, λ = 1.0997 day−1) treated parents were significantly lower than in the control mites (r = 0.1455 day−1, λ = 1.1567 day−1). The lowest fecundity (5.35 eggs/female), occurred in F1 female offspring of parents treated with LC15 concentrations of abamectin, which was significantly lower than in the pyridaben (6.11 eggs/female) and control treatments (11.45 eggs/female). Transgenerational sublethal effects of abamectin and pyridaben in P. pallidus can be effectively used to for optimizing IPM programs against this pest on strawberries.

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Purpose

The present study was designed to compare novel risk factors for cardiovascular diseases (CVD) between hemodialysis (HD) patients with or without protein-energy wasting (PEW) for determining novel risk factors for CVD in HD patients with PEW.

Methods

In this cross-sectional study, 291 HD patients were randomly selected from among 2,302 adult HD patients in Tehran hemodialysis centers. The presence of PEW in HD patients was determined by subjective global assessment. In addition, 4 mL blood was obtained before dialysis and analyzed for serum concentrations of novel risk factors for CVD, including C-reactive protein (CRP), soluble intercellular adhesion molecule type 1 (sICAM-1), soluble vascular cell adhesion molecule type 1 (sVCAM-1), sE-selectin, malondialdehyde (MDA), nitric oxide (NO), endothelin-1 and lipoprotein (a) [Lp (a)].

Results

Serum CRP and sICAM-1 were significantly higher in HD patients with PEW as compared to those without PEW (P < 0.01), whereas there were no significant differences in serum sVCAM-1, sE-selectin, MDA, NO, endothelin-1 and Lp (a) between the two groups. Serum CRP and sICAM-1 were significantly higher in HD patients with PEW type IIa and IIb than in those with PEW type I (P < 0.01).

Conclusion

The present study indicates that serum CRP and sICAM-1, as two CVD risk factors, increase in HD patients with PEW as compared to those without PEW and these increases occur in HD patients with PEW type IIa and IIb who have inflammation.  相似文献   
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Purpose

As central nervous system (CNS) tumors account for second most common childhood malignancies and the first cause of mortality in children with cancer, improving treatment modalities can lead to increase the health care of patients. In this study, we examined the prevalence of childhood brain tumors in patients who referred to MAHAK’s Pediatric Cancer Treatment and Research Center (MPCTRC) for treatment.

Methods

A retrospective review of all children less than 15 years old with a CNS histologically proven tumor, who presented to MPCTRC from April 2007 to April 2010, was performed. Data was analyzed by SPSS version 19 with Kolmogorov–Smirnov and Chi-square tests.

Results

There were 198 (124 boys) children eligible for the study. The majority of the tumors were infratentorial (n?=?134), and the rest were supratentorial (n?=?60) and spinal (n?=?4) cases. The median age was 6.11?±?3.65 years old. Medulloblastoma (n?=?66), low-grade glioma (n?=?52), and high-grade glioma (n?=?40) were the most common tumors. The mean duration of follow-up was 21 months. At the time of this analysis, there were 105 (53 %) children alive, 82 (41.4 %) deaths, and 11 (5.6 %) lost for follow-up. The survival rate was 51.68?±?5.22 %.

Conclusions

In contrast of high rate of death in this study, other general characteristics can serve as benchmark for improving our care for children with brain tumors in Iran.  相似文献   
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