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991.
Purpose:Stress and Type A personality are established risk factors for the development of central serous chorioretinopathy (CSC). Meditation is known to have a positive effect on reducing stress levels. This study aimed to assess the effect of short-term meditation training in patients of CSC.Methods:A pilot study was conducted where 40 patients diagnosed with acute and non-resolving CSC were randomly assigned to either of two groups – meditation training and routine care (without meditation). The primary outcome measure was time to resolution of CSC based on optical coherence tomography and fluorescein angiography. Secondary outcome measures were changes in anxiety score (State–Trait Anxiety Inventory [STAI] scores) and blood pressure. The patients were followed up for a minimum period of 4 months.Results:Twenty cases were included in each group. The demographic pattern, baseline swept-source optical coherence tomography parameters, and STAI scores were similar in both groups. The time to disease resolution was 9.4 ± 4.22 weeks in the meditation group and 19.5 ± 2.79 weeks in the nonmeditation group (P < 0.001). At 4 months, CSC had failed to resolve in 60% of patients with routine care compared with 8% in cases following short-term meditation training. STAI scores showed a reduction in stress levels in the meditation group. Furthermore, statistically significant improvement in systolic and diastolic blood pressures was also observed following meditation training.Conclusion:Short-term meditation training may be a useful approach in the management of patients with CSC as it tends to reduce stress and prehypertension, and promotes earlier resolution of the condition. However, patient’s motivation to complete and pursue the meditation training is a significant barrier.  相似文献   
992.
COVID‐19 pneumonia causes several complications that include pneumothorax, hydropneumothorax, empyema, and rarely leads to bronchopleural fistula (BPF). BPF is a communication between the pleural space and the bronchial tree. We report a case of 24 years man with pneumothorax, hydropneumothorax, and BPF that appeared after COVID‐19 infection.  相似文献   
993.
STUDY OBJECTIVE: To assess the effect of laparoscopic surgery on the survival of women with early-stage endometrial cancer and to analyze the factors that affect survival. DESIGN: Retrospective cohort study (Canadian Task Force classification II-2). SETTING: Tertiary teaching hospital. PATIENTS: Women with clinical stage I and II endometrial cancer (International Federation of Gynecology and Obstetrics staging, 1971) from January 1993 through June 2003. INTERVENTION: Demographic, surgical, perioperative, and pathologic characteristics of women treated with laparoscopy or laparotomy were compared by use of Fisher's exact test or the Student t test. Recurrence-free and overall survival was calculated by use of the Kaplan-Meier method. Stratified analyses were performed with the log-rank test for factors affecting survival (surgical stage, histologic study, and grade). MEASUREMENTS AND MAIN RESULTS: Sixty-seven and 127 women were treated with laparoscopy and laparotomy, respectively. Median follow-up was 36.3 months for the laparoscopy group and 29.6 months for the laparotomy group. The complication rates in the 2 groups were comparable. Women undergoing laparoscopy had shorter hospital stay and less morbidity related to infection. The 2- and 5-year estimated recurrence-free survival rates for the laparoscopy and laparotomy groups (93 % vs 91.7% and 88.5% vs 85%, respectively), as well as the overall 2- and 5-year survival rates (100% vs 99.2% and 100% vs 97%, respectively) were similar. CONCLUSIONS: Laparoscopic surgery in women with early-stage endometrial carcinoma resulted in survival rates similar to laparotomy, although a small sample size precludes definitive conclusions. A larger randomized comparison of the 2 techniques is needed to validate these findings.  相似文献   
994.
In order to use III–V compound semiconductors as active channel materials in advanced electronic and quantum devices, it is important to achieve a good epitaxial growth on silicon substrates. As a first step toward this, we report on the selective-area growth of GaP/InGaP/InP/InAsP buffer layer nanotemplates on GaP substrates which are closely lattice-matched to silicon, suitable for the integration of in-plane InAs nanowires. Scanning electron microscopy reveals a perfect surface selectivity and uniform layer growth inside 150 and 200 nm large SiO2 mask openings. Compositional and structural characterization of the optimized structure performed by transmission electron microscopy shows the evolution of the major facet planes and allows a strain distribution analysis. Chemically uniform layers with well-defined heterointerfaces are obtained, and the topmost InAs layer is free from any dislocation. Our study demonstrates that a growth sequence of thin layers with progressively increasing lattice parameters is effective to efficiently relax the strain and eventually obtain high quality in-plane InAs nanowires on large lattice-mismatched substrates.  相似文献   
995.
Human epithelial cell density was determined from flat preparation of 195 cataractous lenses from 108 males and 87 females between 30 and 80 years of age. The mature cataracts had significantly lower cell counts than the other cataracts. Cell density was significantly higher in the females than in the males. Morphohistological study of the epithelia was focused on the following cataract types: (1) nuclear, (2) posterior subcapsular, (3) mature, (4) mixed, (5) hypermature, and (6) black. The major cataractous changes in all types involved vacuolization of the cytoplasm. The mature types of cataractous epithelia showed 56% superimposed cells; the epithelia in nuclear, posterior subcapsular, and black cataracts showed between 6% and 16%. In the hypermature cataracts, four of five tissues analyzed showed superimposed cells. The superimposed areas are probably the source of increased and altered cell activity. We propose that the metaplastic processes leading to posterior capsular opacification originate from these areas. The majority of nuclear and black cataracts were almost similar to the normal human lens epithelium with more or less uniform distribution of cells. Nucleus shrinkage (5 microns) was more evident in nuclear cataracts; in subcapsular cataracts most of the nuclei were large (average 9 microns diameter). Variation in morphological changes like vacuolization of cytoplasm and nuclei, pyknotic nuclei, and superimposed cells was more evident in the mixed type of cataracts.  相似文献   
996.
Cadmium-induced lipid peroxidation (LPO) in the presence of various hydroxyl radical-generating media was studied in rat liver slices. In the absence of such media, Cd showed an inhibitory action on LPO in vitro. Cd-induced LPO in liver slices in the presence of OH radical-generating media was inhibited by antioxidants. The findings indicate that Cd induced LPO as a result of the presence of transition metal ions and the generation of hydroxyl radicals.  相似文献   
997.
998.
Diagnostic imaging of human neuroblastoma with radiolabeled antibody   总被引:2,自引:0,他引:2  
In a previous study, the authors showed that iodine-131 labeled monoclonal antibody (Mab 3F8) could be used to image human neuroblastoma xenografts in mice with excellent tumor-to-tissue ratios. In this study they report their experience with six patients scanned with radiolabeled 3F8. There was strong accumulation of the labeled antibody in viable tumor, but no significant uptake was noted in normal brain, liver, spleen, or adrenal glands. Tumor-to-nontumor activity ratios varied but were approximately 10:1-20:1. This ratio yields good contrast for visualization. Time-activity curves show that radioactivity levels in normal tissue have a half-time of about 40 hours, whereas tumor tissues show a half-time of about 60 hours. Significant gastric secretion of free iodine demonstrated that the Mab was being deiodinated. Calculated radiation doses indicate that tumors receive at least ten times the dose to other tissues. The results indicate that Mab 3F8 has clinical potential for both imaging and therapy of human neuroblastomas.  相似文献   
999.
AIMS: Clinical trials comparing carotid artery stenting (CAS) with carotid endarterectomy (CEA) for patients with symptomatic carotid artery disease have produced conflicting results. We performed a meta-analysis to systematically evaluate currently available data by comparing CAS with CEA in patients with symptomatic carotid artery disease. METHODS AND RESULTS: We searched MEDLINE, Embase, ISI Web of Knowledge, Current Contents, International Pharmaceutical Abstracts databases, the Cochrane Central Register of Controlled Trials, and scientific meeting abstracts up to 31 October 2006 and then calculated summary risk ratios (RRs) for mortality, stroke, disabling stroke, and death using random- and fixed-effect models. Data from five trials with 2122 patients were pooled. There was no difference in risk of 30-day mortality (summary RR 0.57, 95% CI 0.22-1.47, P = 0.25), stroke (summary RR 1.64, 95% CI 0.67-4.00, P = 0.34), disabling stroke (summary RR 1.67, 95% CI 0.50-5.62, P = 0.50), death and stroke (summary RR 1.54, 95% CI 0.81-2.92, P = 0.19), or death and disabling stroke (summary RR 1.19, 95% CI 0.57-2.51, P = 0.64) among patients randomized to CAS, compared with CEA. CONCLUSIONS: No significant differences could be identified between CAS and CEA in the treatment of patients with symptomatic carotid artery disease. Larger randomized controlled trials are warranted to compare the two strategies.  相似文献   
1000.
The leptin regulation of bone remodeling, which has been documented through studies of loss-of-function mutations of this hormone or of its receptor in mice and humans, still raised several unanswered questions. For instance, it has been assumed but not formally demonstrated that this regulation occurs through neuronal means. Likewise, it has not been possible until now to dissociate the influence leptin exerts on appetite and energy expenditure from this function. We show here through mouse genetic studies that a deletion of the leptin receptor in neurons results in an increase in bone formation and bone resorption, resulting in a high bone mass as seen in leptin-deficient mice. In contrast, the same deletion in osteoblasts only does not influence bone remodeling. Furthermore, through the use of l/l mice, a model of gain of function in leptin signaling harboring a Y985L substitution in the leptin receptor, we show that leptin signaling inhibits bone mass accrual by up-regulating sympathetic activity independently of any change in appetite or energy expenditure. This work establishes that in vivo leptin regulates bone mass accrual by acting through neuronal means and provides a direct demonstration that this function of leptin can occur independently of its regulation of energy metabolism.  相似文献   
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