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71.

Background

Previous studies reported that, in non-degenerate discs, the nucleus pulposus migrates posteriorly during flexion and anteriorly during extension within the intervertebral disc. However, in these studies the differences between anterior and posterior distances have been regarded as an indicator of nucleus pulposus migration. This study investigated the reality of migration of the nucleus pulposus within the intervertebral disc with changing postures.

Method

Magnetic resonance images were obtained of the lumbar spines of 25 asymptomatic volunteers in sitting, standing and supine postures. The anterior and posterior height of the intervertebral disc, the anterior -posterior length of the intervertebral disc and nucleus pulposus, and the positions of the anterior and posterior margins of the nucleus were measured from mid-line sagittal images.

Findings

Changing postures altered the anterior and posterior height of the disc and three types of morphological changes, including changes in the anterior -posterior lengths of the intervertebral disc and nucleus pulposus, together with the position of the nucleus in the disc were found. The length of the intervertebral disc and nucleus pulposus changed under the variations in spinal loading caused by posture.

Interpretation

The results of this study indicated that the apparent nucleus pulposus migration within intervertebral disc is actually deformation of the nucleus pulposus length which depends on posture and the magnitude of the load. In other words, adopting different postures deforms the nucleus pulposus and therefore, changes the position of the nucleus pulposus but there is no apparent nucleus pulposus migration within the intervertebral disc.  相似文献   
72.
Colon cancer ranks first among digestive cancers. The warning signs are dominated by transit disorders, rectal bleeding and pain. However, a colon cancer can be discovered following a complication namely a bowel obstruction, a perforation. Although they are common at diagnosis (25% of the patients), synchronous metastases are an exceptional way of revealing this cancer. We report a case of synchronous ovarian metastasis isolated jacks for an ovarian tumor and revealing a colonic tumor remained asymptomatic until then.  相似文献   
73.
AIM: To investigate the prevalence and risk factors of gastroesophageal reflux disease (GERD) symptoms in Qashqai migrating nomads with a different life style in Fars province, southern Iran. METHODS: In summer 2006, 748 Qashqai migrating nomads aged 25 years or more were enrolled using a multiple-stage stratified cluster random sampling method. A questionnaire consisting of demographic characteristics, lifestyle and GERD symptoms (heartburn, regurgitation, chest pain, dysphagia, hoarseness and cough) as completed for each subject. RESULTS: The questionnaire was completed in 717 subjects. The prevalence rate of GERD, defined as reflux occurring at least one time per week in the preceding year, was 33% (237 subjects). The prevalence was higher in older individuals (36.0% vs 28.9%, P 〈 0.05) and in those with other gastrointestinal complaints (51.0% vs 27.8%, P 〈 0.001), but not different in obese and non-obese subjects. It was also higher in those consuming fruits and vegetables more than once a week (36.2% vs 17.3%, P 〈 0.001). GERD had a positive correlation with smoking (42.1% vs 27.8%, P 〈 0.001), but a negative relation with non-alcoholic beverages. The association between GERD and non-steroidal antiinflammatory drugs (NSAIDs) consumption was also significant (40.2% vs 25.4%, P 〈 0.001). CONCLUSION: The prevalence of GERD (33%) is very high in Qashqai migrating nomads which may be due to a lower socioeconomic and educational level of these people and difference in the life style. Older age, frequent consumption of fruits and vegetables, smoking and NSAIDs are risk factors for GERD in this population.  相似文献   
74.
Many obesity risk factors have increased during the COVID-19 pandemic, including physical inactivity, poor diet, stress, and poverty. The aim of this systematic review was to evaluate the impact of the COVID-19 pandemic, as well as associated lockdowns or restrictions, on weight change in children and adults. We searched five databases from January 2020 to November 2021. We included only longitudinal studies with measures from before and during the pandemic that evaluated the change in weight, body mass index (BMI) (or BMI z-scores for children), waist circumference, or the prevalence of obesity. Random effects meta-analyses were conducted to obtain pooled estimates of the mean difference in outcomes. Subgroups were evaluated for age groups and diabetes or obesity at baseline. The risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale, and the certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. A total of 74 studies were included (3,213,776 total participants): 31 studies of children, 41 studies of adults, and 2 studies of children and adults. In children, the pooled mean difference was 1.65 kg (95% confidence interval [CI]: 0.40, 2.90; 9 studies) for weight and 0.13 (95% CI 0.10, 0.17; 20 studies) for BMI z-scores, and the prevalence of obesity increased by 2% (95% CI 1%, 3%; 12 studies). In adults, the pooled mean difference was 0.93 kg (95% CI 0.54, 1.33; 27 studies) for weight and 0.38 kg/m2 (95% CI 0.21, 0.55; 25 studies) for BMI, and the prevalence of obesity increased by 1% (95% CI 0%, 3%; 11 studies). In children and adults, the pooled mean difference for waist circumference was 1.03 cm (95% CI −0.08, 2.15; 4 studies). There was considerable heterogeneity observed for all outcomes in both children and adults, and the certainty of evidence assessed using GRADE was very low for all outcomes. During the first year of the COVID-19 pandemic, small but potentially clinically significant increases in weight gain, BMI, and increased prevalence of obesity in both children and adults were observed. Increases were greater in children, and targeted prevention interventions may be warranted.  相似文献   
75.
Aspergillus species are ubiquitous in the environment. Aspergillosis is acquired by inhalation of Aspergillus spores. In normal hosts, spore inhalation rarely causes lung disease. Pulmonary Aspergillosis covers a wide spectrum of clinical syndromes depending on the interaction between Aspergillus and the host (immune-status, prior bronchopulmonary disease). It runs the gamut from invasive Aspergillosis to Aspergillus bronchitis. Invasive Aspergillosis usually occurs in severely immunocompromised patients, typically in neutropenic but also in non-neutropenic patients. Chronic pulmonary Aspergillosis affects patients with chronic structural lung disease such as COPD or previous mycobacterial lung disease, but without other significant immunocompromise. Aspergillus bronchitis affects patients with bronchial disease such as bronchiectasis. Allergic bronchopulmonary Aspergillosis affects patients with bronchial asthma or cystic fibrosis, and is due to an allergic response to Aspergillus.  相似文献   
76.
Aim: Rheumatoid arthritis (RA) is the most common chronic inflammatory erosive joint disease with the worldwide distribution of approximately 0.5–1.0%. Etiology of RA is not exactly known but immunologic and genetic factors play an important role in the pathogenesis of the disease. Genetic factors such as human leukocyte antigens (HLA) are responsible for many autoimmune diseases; therefore we decided to look for a correlation between RA and the presence of HLA‐DQβ1 alleles as possible genetic markers. Methods: Genomic DNA from the whole blood samples of 25 patients with RA and 86 normal individuals as control group were extracted by salting out method. The genomic DNA was amplified by polymerase chain reaction‐sequence specific primer (PCR‐SSP) technique. HLA‐typing was done by this method after optimizing the PCR reaction for each allele. In this procedure seven serological subclasses of HLA‐DQβ1 can be detected. Results: Comparing the results between the patients and controls show a significant increase in the frequency of HLA‐DQ8 (*0302, *0305) alleles in RA patients. The P‐values were 0.007 and the relative risk for these alleles was evaluated higher than 1. Conclusions: The results suggest that DQ8 is the dominant HLA‐DQβ1 allele that is associated with susceptibility to RA in north‐eastern Iran.  相似文献   
77.
This systematic review with meta‐analysis sought to determine the strength of evidence in terms of the impact of common antioxidant supplementations, such as N‐acetylcysteine (NAC), vitamin C, and polyunsaturated fatty acids (PUFA) on perioperative outcomes after cardiac surgery with particular focus on the incidence of atrial fibrillation (AF) and acute kidney injury (AKI) with associated mortality. A total of 29 trials were identified that reported incidence of AF and 17 trials that reported incidence of AKI. Pooled analysis reported that NAC (OR=0.5; P=.001), vitamin C (OR=0.4; P=.001), and PUFA (OR=0.8; P=.01) administration were associated with significantly reduced incidence of AF. In terms of postoperative AKI, only NAC was shown to be a beneficial supplement that was able to significantly reduce the incidence of AKI (OR=0.7; P=.01), and NAC could also significantly decrease overall mortality (OR=0.3; P=.03) following cardiac surgery. The use of NAC in patients undergoing cardiac surgery should be strongly recommended due to its combined cardio‐renal protective effects and reduced mortality. Also, PUFA and vitamin C might be able to significantly decrease the incidence of arrhythmia; however, reno‐protective effects and impact on overall mortality of these supplements seem to be less impressive.  相似文献   
78.
Neutral endopeptidase (NEP) hydrolyses angiotensins (Ang) I and II and generates angiotensin-(1-7) [Ang-(1-7)]. In humans, the insertion/deletion (I/D) angiotensin-I converting enzyme (ACE) gene polymorphism determined plasma ACE levels by 40%. In rats, a similar polymorphism determines ACE levels which are inversely associated to NEP activity. The objective of this study is to evaluate the relationship between ACE expression and plasma NEP activity in normotensive subjects and in hypertensive patients. In total, 58 consecutive patients with hypertension, evaluated in our Hypertension Clinic, were compared according to their ACE I/D genotypes with 54 control subjects in terms of both plasma ACE activity and NEP activities. Plasma ACE activity was elevated 51 and 70% in both DD ACE groups (normotensives and hypertensives) compared with their respective ID and II ACE groups (P<0.001). A significant effect of the ACE polymorphism and of the hypertensive status on ACE activity was observed (P<0.001). In normotensive DD ACE subjects, NEP activity was 0.30+/-0.02 U/ml, whereas in the normotensive II ACE and in the normotensive ID ACE subjects NEP activity was increased 65 and 48%, respectively (P<0.001). In the hypertensive DD ACE patients, NEP activity was 0.47+/-0.03 U/mg. An effect of the I/D ACE genotypes on NEP activity (P<0.04) and an interaction effect between the I/D ACE genotype and the hypertensive status were also observed (P<0.001). These results are consistent with a normal and inverse relationship between the ACE polymorphism and NEP activity in normotensive humans (as is also observed in rats). This normal relationship is not observed in hypertensive patients.  相似文献   
79.
A new solution for the removal of the smear layer   总被引:8,自引:0,他引:8  
Various organic acids, ultrasonic instruments, and lasers have been used to remove the smear layer from the surface of instrumented root canals. The purpose of this study was to investigate the effect of a mixture of a tetracycline isomer, an acid, and a detergent (MTAD) as a final rinse on the surface of instrumented root canals. Forty-eight extracted maxillary and mandibular single-rooted human teeth were prepared by using a combination of passive step-back and rotary 0.04 taper nickel-titanium files. Sterile distilled water or 5.25% sodium hypochlorite was used as intracanal irrigant. The canals were then treated with 5 ml of one of the following solutions as a final rinse: sterile distilled water, 5.25% sodium hypochlorite, 17% EDTA, or a new solution, MTAD. The presence or absence of smear layer and the amount of erosion on the surface of the root canal walls at the coronal, middle, and apical portion of each canal were examined under a scanning electron microscope. The results show that MTAD is an effective solution for the removal of the smear layer and does not significantly change the structure of the dentinal tubules when canals are irrigated with sodium hypochlorite and followed with a final rinse of MTAD.  相似文献   
80.
Summary The acute effect of alloxan on the incorporation of14C-leucine into isolated rat islets of Langerhans was studied. I.v. administration of alloxan (40 mg/kg body weight) in rats inhibited the subsequentin vitro incorporation of14C-leucine into (pro-)insulin in the isolated islets. Glucose (750 mg/kg body weight), when administered 5 min prior to alloxan, completely protected the islets against alloxan toxicity. The protective effect of glucose was partly reversed when the concentration of alloxan was raised to 80 mg/kg body weight. Similar results of inhibition of (pro-)insulin biosynthesis by alloxan and its protection by glucose were obtained when isolated rat islets were exposed to alloxan and/or glucosein vitro. Islets exposed to glucosein vitro immediately after alloxan exposure showed a slower rate of inhibition of (pro-)insulin biosynthesis, as compared to islets washed before exposure to D-glucose. In view of these findings, it is suggested that there is a common recognition site on B-cell for alloxan and glucose. CDRI Communication No. 2617.  相似文献   
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