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1.
Graded pneumatic dilatation (PD) is an appropriate long-term therapy and botulinum toxin injection (BT) is a relatively short-term therapy in idiopathic achalasia. Their combination has not been previously scrutinized. This study aimed to evaluate the role of BT in enhancing the efficacy of PD with 30 mm balloons. Patients who underwent PD with 30 mm balloons after botulinum toxin injections and a group of age- and sex-matched controls who were treated only with PD were enrolled in the study. Symptom scores were taken before, 1 month after and then every 3 months after PD. There were no significant differences between the two groups in gender, duration or severity of symptoms. One of the 12 patients in the case group relapsed 30 months after PD but the others were in remission for an average of 25.6 months. In the control group, all the patients relapsed after a mean of 12.6 months and needed a 35-mm PD. The cumulative remission rate was significantly higher in the case group compared with the control group (P < 0.01). The mean symptom score decreased by 76% in the case group (P < 0.001) and 53% in the controls (P < 0.01) at the end of the first month. Neither age, sex, nor duration or severity of symptoms were predictive of patients' responses to treatment. It seems that BT may be a meaningful enhancing factor in long-term efficacy of PD. PD with a 30 mm balloon after a BT session may resolve the need for the future higher grade PD.  相似文献   
2.
Dysfunction of the central dopaminergic neurotransmission has been suggested to play an important role in the etiology of certain neuropsychiatric disorders such as drug abuse. It has been shown that the dopamine D2 receptor (DRD2) gene dysfunction is associated with multi-drug addiction. Addiction to opium is the most common form of drug abuse in Iran. We studied the allelic association between DRD2 Taq I A polymorphism in 100 opium-dependent Iranian patients and 130 unrelated controls. A 310 bp (base pair) region surrounding Taq I site at the DRD2 locus was amplified by polymerase chain reaction (PCR) and the PCR product was incubated with Taq I restriction enzyme. The A1 allele remained intact while the A2 allele was cut. Significant association was observed between A1 allele and addiction in the patients group (P < 0.0001). Moreover, the frequency of A1A1 genotype was significantly higher in opium users than controls (P < 0.0001). Our result indicates that DRD2 might be involved in the pathophysiology of opium addiction.  相似文献   
3.
Due to the increasing prices of cement and its harmful effect on the environment, the use of cement has become highly unsustainable in concrete. There is a considerable need for promoting the use of cement replacement materials. This study investigates the effect of variable percentages of metakaolin (MK) on the mechanical and durability performance of concrete. Kaolin clay (KC) was used in the current research to prepare the MK by the calcination process; it was ground in a ball mill to its maximum achievable fineness value of 2550 m2/Kg. Four replacement levels of MK, i.e., 5%, 10%, 15%, and 20% by weight of cement, in addition to control samples, at a constant water-to-cement (w/c) ratio of 0.55 were used. For evaluating the mechanical and durability performance, 27 cubes (6 in. × 6 in. × 6 in.) and 6 cylinders (3.875 in. diameter, 2 in. height) were cast for each mix. These samples were tested for compressive strength under standard conditions and in an acidic environment, in addition to being subjected to water permeability, sorptivity, and water absorption tests. Chemical analysis revealed that MK could be used as pozzolana as per the American Society for Testing and Materials (ASTM C 618:2003). The results demonstrated an increased compressive strength of concrete owing to an increased percentage of MK in the mix with aging. In particular, the concrete having 20% MK after curing under standard conditions exhibited 33.43% higher compressive strength at 90 days as compared to similarly aged control concrete. However, with increasing MK, the workability of concrete decreased drastically. After being subjected to an acid attack (immersing concrete cubes in 2% sulfuric acid solution), the samples exhibited a significant decrease in compressive strength at 90 days in comparison to those without acid attack at the same age. The density of acid attack increased with increasing MK with a maximum corresponding to 5% MK concrete. The current findings suggest that the local MK has the potential to produce good-quality concrete in a normal environment.  相似文献   
4.
Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549?kcal mol?1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4′-hydroxy-2,3,4,5-tetrachlorobiphenyl (4′-OH-TCB) and 4-hydroxy-2,2′,5′-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π–π stacking, hydrophobic, polar and van der Waals’ interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.  相似文献   
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6.

Background

Patients with atrial fibrillation (AF) experience symptom burden, exercise intolerance, weight gain, poor mental health, and diminished quality of life (QoL). Cardiac rehabilitation (CR) is recommended for patients with heart disease, and its benefits are well established, yet clinical guidelines for patients with AF do not include the referral to CR.

Methods

In this matched retrospective, case-control study, we examined the impact of CR on changes in QoL, mental health, and cardiometabolic health indicators in patients with or without persistent or permanent AF. Patients attended CR that addressed risk factor management and provided support services and exercise training twice weekly for 3 months. Height, body mass, waist circumference, blood pressure, and heart rate were measured, and the Short Form-36 and Hospital Anxiety and Depression Scale were administered at baseline and 3 months follow-up.

Results

A total of 94 patients (AF, n = 47; no AF, n = 47) (aged 70 ± 8 years) participated. Significant improvements in 2 of the 8 subscales and the Physical Component Summary of the Short Form-36 were observed across groups after CR (P < 0.05). Significant interactions revealed that the effect of CR was greater for energy, emotional well-being, social functioning, pain, and the Physical Component Summary in patients without AF (P < 0.05 for each). No significant improvements in anxiety (AF: ?1.3 ± 3.4; no AF: ?1.3 ± 4.3), depression (AF: ?1.1 ± 2.9; no AF: ?0.4 ± 2.7), body mass index (AF: ?0.5 ± 1.2; no AF: ?0.8 ± 1.5, kg/m2), waist circumference (AF: ?1.7 ± 4.6; no AF: 0.4 ± 8.1, cm), or blood pressure (AF: ?2.3 ± 17.1/?3.9 ± /9.3; no AF: 1.8 ± 16.4/?0.8 ± /9.3 mm Hg) were observed across groups after CR.

Conclusions

CR improved QoL to a greater extent in patients with heart disease without than with persistent or permanent AF.  相似文献   
7.

Objectives:

To determine the prevalence of dental caries in the primary and permanent teeth, and evaluate the brushing habits of school children in Dammam, Kingdom of Saudi Arabia (KSA).

Methods:

This study was conducted at Dammam, KSA. Oral examination of the participants was conducted from February to May 2014. The total sample size for this cross-sectional study was 711. There were 397 children between the age of 6-9 years, who were examined for primary teeth caries, and 314 between the age 10-12 years were examined for permanent teeth caries. Primary and permanent dentitions were studied for decayed, missing, and filled teeth (dmft [primary teeth], DMFT [permanent teeth]).

Results:

The overall prevalence of dental caries in primary and permanent teeth was almost 73% (n=711). Among the 6-9-year-old, the prevalence of caries was approximately 78% (n=397) whereas, among the 10-12-year-old children, it was approximately 68% (n=314). Mean dmft value among the 6-9-year-olds was 3.66±3.13 with decayed (d) component of 3.28±2.92, missing (m) component of 0.11±0.69, and filled (f) component of 0.26±0.9. Mean DMFT value among the 10-12-year-old children was 1.94±2.0 with decayed (D) component of 1.76±1.85, missing (M) component of 0.03±0.22, and filled (F) of component 0.15±0.73. Daily tooth brushing had a positive effect on caries prevention, and this effect was statistically significant for caries in primary teeth.

Conclusion:

Although the prevalence of dental caries in primary and permanent teeth was not found to be as high as other researchers reported from different cities of KSA, still the prevalence was high considering the World Health Organization future oral health goals. Awareness should be provided to students, as well as, teachers and parents regarding the importance of good brushing habits and regular dental visits.Dental caries is one of the most common cause of extraction of primary teeth in Saudi Arabia.1 In the past few decades, an increase in the prevalence of dental caries has been observed, which can be attributed to a change in lifestyle of Saudis, involving increased consumption of sugary food, carbonated drinks, and lack of awareness towards proper oral health maintenance.2,3 Generally, the prevalence of dental caries in developed countries is decreasing, while in underdeveloped and developing countries, the prevalence is on the rise.4 According to the statistics available from the World Health Organization (WHO), caries prevalence among the 12-year-old children from many European Union states (EU) has decreased considerably from 1970’s to 2006.5 This decline in the caries’ prevalence among EU countries over a period of 35 years could be attributed to an increased awareness of oral hygiene maintenance, and use of fluoridated toothpaste.6 However, among underdeveloped countries where fluoridated toothpaste is not easily available, or not affordable in some cases, caries prevalence is still high.7 The area of dental caries prevalence is of great interest to local and international researchers, which can be indicated by a number of studies that have been performed in developed and developing countries regarding caries’ prevalence.8-10 A study conducted in the urban and rural areas of Lahore, Pakistan to determine whether urbanization and family earnings are related to dental caries reported caries prevalence of 40.5%, and decayed (d), missing (m), and filled (f) teeth (dmft [primary teeth]) score of 1.85 ± 3.26 in preschool children aged 3-5 years,11 while another cross-sectional study performed in Chikar, Pakistan with convenience sampling of 311 schoolchildren revealed an overall DMFT (permanent teeth) score of 3.3 in 5-20-year-olds.12 Several studies have been conducted in different parts of the Kingdom of Saudi Arabia (KSA) to report the prevalence of dental caries in schoolchildren. A study performed in Riyadh reported a dmft score of 6.1, decayed factor of 4.6, and no significant difference in the prevalence of caries in relation to gender among 789 pre-school children.13 Farsi14 conducted a study to develop an association between enamel defects and caries occurrence in Jeddah, KSA, and reported a dmft score of 3.9, and a strong association between enamel defects and caries prevalence among 4-5-year-olds.14 In 2012, caries prevalence in the maxillary and mandibular first molar in the age group of 7-10 years schoolchildren was determined in Abha city, and a mean DMFT of 2.74 was reported.15 It was also concluded in the same study that caries prevalence in the first permanent molars from this region is higher than the recommended standards of the WHO.15 Extensive literature search was carried out to find studies regarding caries’ prevalence from Dammam, KSA. The search resulted in only one study, which was conducted in 2008 on children with cleft lip and palate aged 1-6 years, and it reported a high dmft of 10.54 from Dammam region.16 Since Dammam is one of the largest cities of the Eastern province of KSA, it would be interesting to observe caries’ prevalence among schoolchildren from this city. Therefore, the aim of the present study was to determine the prevalence of dental caries in schoolchildren aged 6-12 years in Dammam, KSA using the dmft/DMFT index of dental caries.  相似文献   
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