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131.

Statement of problem

The loss of posterior teeth has a negative effect on the masticatory efficiency and activity of mastication muscles. How these muscles are affected by partial removable dental prostheses (PRDPs) with different cusp angles is unknown.

Purpose

The purpose of this clinical study was to evaluate the influence of different cusp angles, with anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree), on the masticatory efficiency and muscular activity of participants receiving mandibular bilateral distal PRDPs.

Material and methods

Fifteen participants consented to the evaluation of masticatory efficiency and electromyographic (EMG) activity with a PRDP with a unified bilateral design. The cusp angles of the artificial teeth were randomly changed from anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree). Masticatory efficiency was evaluated by recording 5 parameters, including number of strokes, and time of mastication while the EMG activities of the masseter and temporalis muscles, measured using surface electromyography. The data were analyzed with 1-way ANOVA and the Tukey multiple post hoc test with statistical software (α=.05).

Results

With regard to masticatory efficiency, PRDPs with anatomic and semianatomic teeth exhibited higher masticatory efficiency than those with nonanatomic teeth, whereas no significant differences were found between PRDPs with anatomic and semianatomic teeth. With respect to EMG activity, the least EMG activity was observed in PRDPs with anatomic teeth, whereas the highest activity was observed with nonanatomic teeth. No significant differences were found between the effect of PRDPs with anatomic and semianatomic teeth on masseter activity.

Conclusions

Changing the cusp angle from 33 to 20 degrees in PRDPs did not influence the masticatory efficiency or the EMG activity of the masseters. However, it did lead to increased EMG activities of the temporalis muscle. PRDPs with nonanatomic teeth were associated with a significant decrease in masticatory efficiency accompanied by a significant increase in EMG activity.  相似文献   
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The role of advanced clinical nurse practitioners (ACNPs) is continuously developing to be viewed as a critical contribution to nursing professional development. There is an agreed understanding of the role of ACNP, yet no definitive definition has been proposed. Debate arises about whether ACNP is a medical extension of the nursing role or a holistic approach for the patient care. According to the Nursing and Midwifery Council in the United Kingdom, the code of professional conduct encompasses advanced practitioner practice, meaning that it does not require its own regulation.  相似文献   
135.
ObjectivesThe present study aimed to identify the genetic cause of non-syndromic primary failure of tooth eruption in a five-generation consanguineous Saudi family using whole-exome sequencing (WES) analysis.DesignThe family pedigree and phenotype were obtained from patient medical records. WES of all four affected family members was performed using the 51Mb SureSelect V4 library kit and then sequenced using the Illumina HiSeq2000 sequencing system. Sequence alignment, variant calling, and the annotation of single nucleotide polymorphisms and indels were performed using standard bioinformatics pipelines. The genotype of candidate variants was confirmed in all available family members by Sanger sequencing.ResultsPedigree analysis suggested that the inheritance was autosomal recessive. WES of all affected individuals identified a novel homozygous variant in exon 8 of the parathyroid hormone 1 receptor gene (PTH1R) (NM_000316: c.611T>A: p.Val204Glu).ConclusionTo the best of our knowledge, this is the first report of primary failure of eruption caused by a homozygous mutation in PTH1R. Our findings prove the application of WES as an efficient molecular diagnostics tool for this rare phenotype and further broaden the clinical spectrum of PTH1R pathogenicity.  相似文献   
136.
BACKGROUND AND AIM: To estimate the risk of hepatocellular carcinoma (HCC) in non-alcoholic patients with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, 118 patients who were admitted to a regional hospital in Saudi Arabia were compared with 118 age- and sex-matched healthy individuals. RESULTS: The prevalence of HBsAg in HCC patients (67%; 95% confidence interval (CI): 57.7-75.3) was significantly higher than the rate (6.7%; 95%CI: 3.0-12.9) in the controls (OR: 28.4; 95%CI: 12.6-63.9; P < 0.001). There was a high risk of HCC in the presence of HBsAg alone (OR: 34.3; 95%CI: 14.8-79.1, P < 0.001) and anti-HCV alone (OR: 12.2; 95%CI: 3.2-47.2; P < 0.001). Although HBV and HCV were independent risk factors in the development of HCC, there was no interactive relationship between the two viruses. Dual infections occurred in only 3.4% and were associated with only a moderate increase in the risk of HCC (OR: 14.6; 95%CI: 1.57-135.9). In 24.6% of the cases no virus was identified as the etiologic factor. CONCLUSION: Hepatitis B virus constitutes a major risk factor and HCV contributes a less significant role in the development of HCC. The ongoing program of HBV vaccination may significantly decrease the prevalence of HBV-associated HCC in this population.  相似文献   
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138.

Objectives

Gestational diabetes mellitus (GDM) is recognized as an imbalance between insulin resistance and insulin secretion, leading to maternal hyperglycemia. Previous studies in a Saudi population indicated a high frequency of Paraoxonase 1 glutamine 192 to arginine (PON1 Q192R) polymorphism, suggesting this polymorphism as an additional risk factor. The present study was designed to explore the possible association between the PON1 Q192R polymorphism and GDM in a Saudi population.

Methods

This case–control study was carried out in 500 pregnant women, including 200 GDM cases and 300 non-GDM women. Genotyping for PON1 Q192R (rs662) variants was performed by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).

Results

The results of the present study indicates that Q192R polymorphism was significantly associated with GDM in a Saudi population with the minor allele frequency (MAF) (p = 0.0007). Q192R genotypes and alleles showed a strong association with GDM (p = 0.009 and p = 0.0007, respectively).

Conclusion

In conclusion, these findings suggest that the PON1 Q192R polymorphism has high MAF in GDM in the studied Saudi population.  相似文献   
139.
ObjectiveMetabolic bone disease concerns a broad spectrum of conditions related to reduced bone density. Metabolic bone disease has been linked to chronic inflammatory diseases, such as ulcerative colitis. This study examines the prevalence of metabolic bone disease in ulcerative colitis patients and explores possible clinical predictors.MethodThe authors performed a retrospective study involving children and adolescents with confirmed ulcerative colitis between January 2013 and December 2018. Bone density was evaluated through a dual-energy X-ray absorptiometry scan of the spine and total body. Osteoporosis was defined as a bone mineral density Z-score of <?2 and osteopenia as a Z-score of between ?1.0 and ?2.ResultsA total of 37 patients were included in this analysis, with a mean age of 13.4 ± 3.9 years and a mean duration of illness of 2.1 ± 2.4 years. Using lumbar spine Z-scores and total body Z-scores, osteoporosis and osteopenia were identified by dual-energy X-ray absorptiometry scan measurements in 11 patients (29.7%) and 15 patients (40.5%), and in ten patients (27%) and 13 patients (35%), respectively. Lumbar spine Z-scores were significantly positively associated with male gender (B = 2.02; p = 0.0001), and negatively associated with the presence of extraintestinal manifestations (B = ?1.51, p = 0.009) and the use of biologics (B = ?1.33, p = 0.004). However, total body Z-scores were positively associated with body mass index Z-scores (B = 0.26, p = 0.004) and duration of illness in years (B = 0.35, p = 0.003).ConclusionsMetabolic bone disease is very common in this cohort of Saudi Arabian children and adolescents with ulcerative colitis and its occurrence appears to increase in female patients who suffer from extraintestinal manifestations.  相似文献   
140.
Graduate doctors are the primary output of medical education programmes. It is important for institutions to identify systematically the types of medical activities in which their former students are involved in order to determine the effectiveness of the curriculum, assessing academic standards and reviewing admissions policies. Information was obtained from a survey of men and women graduates from three of the early graduation classes of King Abdulaziz University College of Medicine in Saudi Arabia about postgraduate medical training, certification, practice patterns, and other curriculum issues. Information collected from 151 graduates (90%) indicated that 96% were practising medicine in a variety of medical specialties and subspecialties. Six were not practising at the time of the study. Significant differences were found in the specialties being practised when men and women were compared. Men tended to practise in medicine, surgery, dermatology, urology, ENT, ophthalmology and orthopaedics, while women concentrated in obstetrics and gynaecology and paediatrics. Certification beyond medical school was earned by 49% with no significant difference being found comparing men to women. Men earned the majority of their postgraduate certifications outside Saudi Arabia while most women earned theirs in Saudi Arabia. Graduates indicated that departments in the basic sciences were least helpful in preparing them as doctors, while selected clinical departments were most helpful. It was concluded from the study that the curriculum goals of the College of Medicine, namely a curriculum of international standards producing graduates to take leadership roles in both teaching and medical practice, were realized in part by the graduates surveyed.  相似文献   
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