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981.
982.
983.
Late in 2019, several cases of infection with a new strain of coronavirus were reported in China. This new strain was later officially named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the World Health Organization (WHO). This new virus (SARS-CoV2-) mainly affects the respiratory system and causes coronavirus disease 2019 (COVID-19). The first case of COVID-19 was reported to the WHO on December 31st, 2019, and the virus has spread dramatically in many countries worldwide. On March 11th, 2020, the WHO declared that COVID-19 had affected most of the world, and many deaths were linked to COVID-19. Unfortunately, there is no available treatment for COVID-19, and there is no available vaccine against SARS-CoV-2. Thus, preventive methods are the only way to limit the spread of the virus. Preventive actions have been taken by many countries, such as travel bans, closing borders and working from home. Saudi Arabia was one of the countries that took very early precautionary actions in the belief that these actions are the best way to fight the virus. Therefore, we present the actions that were taken by the Kingdom of Saudi Arabia to fight the new viral pandemic.  相似文献   
984.

Background/Aims:

Colorectal cancer (CRC) is the second most common malignancy in the Saudi population, with an increasing incidence over the past 20 years. We aim to determine the baseline polyp as well as adenoma prevalence in a large cohort of patients and to find the possible age in which, if deemed appropriate, a CRC screening program should be initiated.

Patients and Methods:

A retrospective cohort study was conducted using an endoscopic reporting database of individuals seen at a major tertiary care university hospital (King Khalid University Hospital) in Riyadh, Saudi Arabia. Consecutive Saudi patients who underwent a colonoscopy between August 2007 and April 2012 were included. Patients were excluded if the indication for the colonoscopy was colon cancer, colonic resection, active colitis, active diverticulitis, inflammatory bowel disease, or if the patient was referred for polypectomy.

Results:

2654 colonoscopies were included in the study. The mean age of the study population was 50.5 years [standard deviation (SD) 15.9] and females represented 57.7%. The polyp detection rate in completed colonoscopies was 20.8% (95% CI: 19.2-22.5). Adenomas were found in 8.1% (95% CI: 7.1-9.1), while advanced adenomas were found in only 0.5% (95% CI: 0.2-0.7). Adenomas were found in the left side of the colon in 33.9%, followed by the rectum in 14.6%, ascending colon and cecum in 14.2%, transverse colon in 8.7%, and in multiple locations in 28.7%. Those with a prior history of polyps or CRC were more likely to have an adenoma at colonoscopy than those who did not (14.3% vs. 6.6%; P < 0.01). The adenoma prevalence varied between age groups and ranged from 6.2% to 13.6% with a higher proportion in older individuals; this trend was seen both in males (6.0-14.5%) and females (6.4-14.6%) as well as in those who had screening colonoscopies (6.3-18.4%). No age could be found at which a CRC screening program would be appropriate to initiate.

Conclusion:

The prevalence of polyps and adenomas in this cohort is less than that reported in the Western populations. But as this cohort included younger and symptomatic patients with only a small proportion undergoing screening, further studies in an asymptomatic population are needed.  相似文献   
985.

Background/Aims:

Despite the remarkable increase in the incidence of Crohn''s disease among Saudis in recent years, data about Crohn''s disease in Saudi Arabia are scarce. The aim of this study was to determine the clinical epidemiology and phenotypic characteristics of Crohn''s disease in the central region of Saudi Arabia.

Patients and Methods:

A data registry, Inflammatory Bowel Disease Information System (IBDIS), was used to register Crohn''s disease patients who presented to the gastroenterology clinics in four tertiary care centers in Riyadh, Saudi Arabia between September 2009 and February 2013. Patients’ characteristics, disease location, behavior, age at diagnosis according to the Montreal classification, course of the disease, and extraintestinal manifestation were recorded.

Results:

Among 497 patients with Crohn''s disease, 59% were males with a mean age at diagnosis of 25 years [95% Confidence Interval (CI): 24-26, range 5-75 years]. The mean duration from the time of complaint to the day of the diagnosis was 11 months, and the mean duration of the disease from diagnosis to the day of entry to the registry was 40 months. Seventy-seven percent of our patients were aged 17-40 years at diagnosis, 16.8% were ≤16 years of age, and 6.6% were >40 years of age. According to the Montreal classification of disease location, 48.8% of patients had ileocolonic involvement, 43.5% had limited disease to the terminal ileum or cecum, 7.7% had isolated colonic involvement, and 16% had an upper gastrointestinal involvement. Forty-two percent of our patients had a non-stricturing, non-penetrating behavior, while 32.8% had stricturing disease and 25.4% had penetrating disease.

Conclusion:

Crohn''s disease is frequently encountered in Saudi Arabia. The majority of patients are young people with a predilection for males, while its behavior resembled that of western societies in terms of age of onset, location, and behavior.  相似文献   
986.

Background

The foundation of best practice in health promotion is a robust theoretical base that informs design, implementation, and evaluation of interventions that promote the public’s health. This study provides a novel contribution to health promotion through the adaptation of the agenda-setting approach in response to the contribution of social media. This exploration and proposed adaptation is derived from a study that examined the effectiveness of Twitter in influencing agenda setting among users in relation to road traffic accidents in Saudi Arabia.

Objective

The proposed adaptations to the agenda-setting model to be explored reflect two levels of engagement: agenda setting within the social media sphere and the position of social media within classic agenda setting. This exploratory research aims to assess the veracity of the proposed adaptations on the basis of the hypotheses developed to test these two levels of engagement.

Methods

To validate the hypotheses, we collected and analyzed data from two primary sources: Twitter activities and Saudi national newspapers. Keyword mentions served as indicators of agenda promotion; for Twitter, interactions were used to measure the process of agenda setting within the platform. The Twitter final dataset comprised 59,046 tweets and 38,066 users who contributed by tweeting, replying, or retweeting. Variables were collected for each tweet and user. In addition, 518 keyword mentions were recorded from six popular Saudi national newspapers.

Results

The results showed significant ratification of the study hypotheses at both levels of engagement that framed the proposed adaptions. The results indicate that social media facilitates the contribution of individuals in influencing agendas (individual users accounted for 76.29%, 67.79%, and 96.16% of retweet impressions, total impressions, and amplification multipliers, respectively), a component missing from traditional constructions of agenda-setting models. The influence of organizations on agenda setting is also highlighted (in the data of user interactions, organizational accounts registered 17% and 14.74% as source and target of interactions, respectively). In addition, 13 striking similarities showed the relationship between newspapers and Twitter on the mentions trends line.

Conclusions

The effective use of social media platforms in health promotion intervention programs requires new strategies that consider the limitations of traditional communication channels. Conducting research is vital to establishing a strong basis for modifying, designing, and developing new health promotion strategies and approaches.  相似文献   
987.
We investigated whether the c.47T?>?C polymorphism (SNP rs4880) in the manganese superoxide dismutase (SOD2) gene is a risk factor for primary angle closure glaucoma (PACG) in the Saudi population. Among cases (n?=?139), the prevalence of various genotypes were 25.9%, 46.8% and 27.3% for T/T, C/T and C/C genotypes respectively. This trend was similar in the controls (n?=?403); 22.6%, 50.1% and 27.3% for T/T, C/T and C/C respectively. The differences in genotype distribution were not statistically significant (p?=?0.391 and 0.682 respectively). The minor allele frequency was 50.7% in cases and 52.4% in controls; this difference was not statistically significant (p?=?0.676). Investigating the potential association between this SOD2 polymorphism and different clinical indices, there was a statistically significant difference among different genotype groups in terms of three important clinical indices for PACG; Mean age at onset, duration of onset to and the mean LogMAR visual acuity (p?=?0.041, 0.018 and 0.033 respectively). The three markers are highly associated prognostic factors to diseases severity. If our results are proven in larger cohort and in various populations, then this SNP may have potentiality to be used as an indicator for PACG severity.  相似文献   
988.
989.
990.
To our knowledge, this study may be the first to examine the antagonistic role of selenium (Se) on oxidative stress induced by cadmium (Cd) and its impact on birth measures. Cd and Se levels were measured in umbilical-cord blood and the placentas of a subsample of 250 healthy mothers who participated between 2005 and 2006 in the project “Prenatal Exposure to Pollutants”. The median Cd levels in cord and maternal blood and placental tissue were 0.78 μg/l, 0.976 μg/l and 0.037 μg/g dry wt., respectively. The median levels of Se in cord serum and placental tissue were 65.68 μg/l and 1.052 μg/g dry wt., respectively. Se was more than 100-fold in molar excess over Cd in both cord serum and placental tissue. The median molar Cd/Se ratios in cord serum and placental tissue were 0.008 and 0.024, respectively, which were much lower than unity. This study suggests that both Cd and Se play a role in the mechanism of oxidative stress, but, the process underlying this mechanism remains unclear. Nevertheless, three biomarkers of oxidative stress had inconsistent relationships with Cd and/or Se in various matrices, perhaps due to potential untested confounders. Our results generally support an association between low in utero exposure to Cd and the anthropometric development of the fetus. Adjusted regression models indicated a negative association of cord blood Cd levels ≥0.78 μg/l with Apgar 5-min scores and birth height. Maternal Cd levels ≥0.976 μg/l were associated with a 5.94-fold increased risk of small-for-gestational-age births, which increased to 7.48-fold after excluding preterm births. Placenta weight decreased with increasing placental Cd levels ≥0.037 μg/g dry wt. (p = 0.045), an association that became stronger after excluding preterm births or adjusting for birth weight. Cord Se levels ≥65.68 μg/l were positively associated with placenta weight (p = 0.041) and thickness (p = 0.031), an association that remained unchanged after excluding preterm births. Cord Se levels, however, were negatively associated with cephalization index, but only after excluding preterm births (p = 0.017). Each birth measure was again modeled as a function of the Cd/Se ratios in cord blood and placenta tissue. Interestingly cord ratios ≥0.008 were negatively associated with Apgar-5 min score (p = 0.047), birth weight (p = 0.034) and placenta thickness (p = 0.022). After excluding preterm births, only the association with placenta thickness remained significant (p = 0.021), while birth weight (p = 0.053) was marginally significant. In contrast, cephalization index increased with Cd/Se ratios ≥0.008 (p = 0.033), an association that became marginally significant after excluding preterm births (p = 0.058). For placental Cd/Se ratios ≥0.024, only placenta weight was reduced with (p = 0.037) and without (p = 0.009) the inclusion of preterm births. These findings do not support an antagonistic mechanism between Cd and Se. The role of oxidative mechanisms either induced by Cd exposure or alleviated by Se on these birth anthropometric measures was examined by principal component analysis. Se did not have a clear protective role against Cd-induced adverse effects despite its substantial excess over Cd, and its role in alleviating oxidative stress by reducing malondialdehyde levels. The results may suggest that the extent of the Se beneficial effects is not governed only by its concentration but also by the chemical forms of Se that interact with various proteins. Consequently, the speciation of Se in such studies is essential for understanding and predicting Se availability for absorption.  相似文献   
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