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71.
PURPOSE: To determine the frequency and natural course of mediastinal masses in asymptomatic people at high risk for lung cancer who were undergoing computed tomographic (CT) screening. MATERIALS AND METHODS: Informed consent and institutional review board approval for this HIPAA-compliant study were obtained at each participating institution. All documented mediastinal masses among the 9263 baseline and 11 126 annual repeat screenings performed in the Early Lung Cancer Action Project (ELCAP) and its successor project, the New York ELCAP, were identified. Two radiologists confirmed all cases, identified the location and measured the diameter (average of length and width) of each mass, and reviewed all subsequent CT and clinical and surgical results. The prevalence and incidence of mediastinal masses were then determined. RESULTS: Of the 9263 individuals, 71 had a mediastinal mass seen at baseline screening (prevalence of 0.77%). Of the 71 masses, 41 were thymic, 16 were thyroidal, two were esophageal cancers, six were tracheal-esophageal diverticula, and six were other masses. Among the 11 126 annual repeat screenings, only one new mediastinal mass was identified (incidence of 0.01%). This suggests a long average duration for mediastinal masses in asymptomatic people. Among the 41 thymic masses, five were larger than 3.0 cm in diameter, and all five were resected; of these five, one was a thymic carcinoma and four were noninvasive thymomas. Of the remaining 36 thymic masses, 25 were evaluated at follow-up CT 1 year later: Five had increased in diameter, two had decreased, and 18 remained unchanged. All 16 thyroid masses were due to goiter; none of these were changed at follow-up CT 1 year later. CONCLUSION: Mediastinal masses found in the context of CT screening for lung cancer in asymptomatic people should be approached in a "conservative" manner; this includes thymic masses smaller than 3 cm in diameter, as most of these remain unchanged or even decrease in size.  相似文献   
72.
Two new functionalized π-extended benzofuran catechol porphyrins and nanostructured Mn-porphyrins have been synthesized by a green one-pot method and structurally characterized by spectroscopic analysis. The electro-oxidation of 5,10,15,20-tetrakis(2,3-dihydroxyphenyl) porphyrins(1a-b) with four catechol units in the presence of 3-hydroxy-1H-phenalene-1-one (3) as bidentate nucleophile has been done and benzofuran rings have formed by the intermolecular and intramolecular Michel addition reactions. Coulometry and voltammetry results allowed us to propose four independent ECEC mechanisms for the electrochemical oxidation pathway. Functionalization of the porphyrins affected their photophysical properties such as the efficiency of the fluorescence that would support the energy transfer between the porphyrin core and the substituted subunits.  相似文献   
73.
Background

Laparoscopic sleeve gastrectomy (LSG) is a well-established bariatric procedure. A staple line leak is a recognized complication of LSG. Bougie size has been suggested to impact leak rates. In this study, we evaluate the impact of using 32–34F bougie sizes with LSG on early postoperative outcomes including staple line leaks within our practice.

Methods

This is a retrospective cohort analysis of a prospectively maintained database of all LSG procedures performed between January 2012 and December 2018 at a single medical center. Data collected and analyzed included bougie size, postoperative leak rate, need for re-operation, 12-month excess weight loss, and 30-day morbidity and mortality.

Results

During the study period, 3153 patients underwent LSG, of whom 1977 (62.7%) were female. Mean age and body mass index (BMI) were 42.9 ± 12.2 years (range 15–76 years) and 42.4 ± 5.2 kg/m2 (range 27–73), respectively. No intraoperative complications or mortality occurred. There was one case of perioperative mortality due to bleeding (0.03%). Early postoperative adverse events occurred in 131 patients (4.1%): 17 leaks (0.5%), 75 bleeds (2.4%), and 39 (1.2%) other.

Conclusion

The use of smaller-sized (32–34F) bougies had no impact on staple line leaks in the hands of experienced bariatric surgeons at a high-volume center.

  相似文献   
74.

Background:

The biological effects of hemostatic agends on the physiological healing process need to be tested. The aim of this study was to assess the effects of oxidized cellulose (surgicel) and bone wax on bone healing in goats’ feet.

Materials and Methods:

Three congruent circular bone defects were created on the lateral aspects of the right and left metacarpal bones of ten goats. One defect was left unfilled and acted as a control; the remaining two defects were filled with bone wax and surgicel respectively. The 10 animals were divided into two groups of 5 animals each, to be sacrificed at the 3rd and 5th week postoperatively. Histological analysis assessing quality of bone formed and micro-computed tomography (MCT) measuring the quantities of bone volume (BV) and bone density (BD) were performed. The results of MCT analysis pertaining to BV and BD were statistically analyzed using two-way analysis of variance (ANOVA) and posthoc least significant difference tests.

Results:

Histological analysis at 3 weeks showed granulation tissue with new bone formation in the control defects, active bone formation only at the borders for surgicel filled defects and fibrous encapsulation with foreign body reaction in the bone wax filled defects. At 5 weeks, the control and surgicel filled defects showed greater bone formation; however the control defects had the greatest amount of new bone. Bone wax filled defects showed very little bone formation. The two-way ANOVA for MCT results showed significant differences for BV and BD between the different hemostatic agents during the two examination periods.

Conclusion:

Surgicel has superiority over bone wax in terms of osseous healing. Bone wax significantly hinders osteogenesis and induces inflammation.  相似文献   
75.
Surgery remains the only treatment with a chance of cure for renal cell carcinoma. Laparoscopic radical nephrectomy (LRN) has developed to be a standard treatment for the management of suspected renal malignancy in many centers worldwide, with oncologic efficacy equal to that of open radical nephrectomy. LRN has considerable advantages over open surgery, such as decreased postoperative morbidity, decreased analgesic requirements, and shorter hospital stay and convalescence. Current indications for LRN include all patients with localized stage T1-2 renal tumors. LRN for stage T3 renal tumors may be technically feasible in individual situations, but cannot be considered standard treatment. Open radical nephrectomy is reserved for advanced renal tumors, according to the surgeon's judgment. Partial nephrectomy is well established and considered to be the standard management for all organ-confined tumors of 相似文献   
76.
BackgroundEvidence remains contradictory for perioperative outcomes of super-obese (SO) and super-super-obese (SSO) patients undergoing bariatric surgery.ObjectiveTo identify national 30-day morbidity and mortality of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) in SO and SSO patients.SettingThe Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database.MethodsAll LSG and LRYGB patients from 2015 through 2017 in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database were grouped based on body mass index (BMI) as follows: morbidly obese (MO; BMI 35.0–49.9 kg/m2), SO (BMI 50.0–59.9 kg/m2), and SSO (BMI ≥60.0 kg/m2). Complications and mortality within 30 days were compared between BMI groups using Pearson X2 or Fischer’s exact tests. Multivariate logistic regression was used to adjust for demographic characteristics and co-morbidities, and adjusted odds ratio (AOR) was reported for each outcome.ResultsOf 356,621 patients, 71.6% had LSG and 28.4% LRYGB. A total of 272,195 patients were in the MO group, 65,565 in the SO group, and 18,861 in the SSO group. Higher BMI was associated with increased overall morbidity and mortality. The overall complication rate was significantly higher for SO (AOR = 1.20, 95% confidence interval [CI] 1.13–1.28 for LSG; AOR = 1.08, 95% CI 1.01–1.15 for LRYGB) and SSO (AOR = 1.44, 95% CI 1.31–1.58 for LSG; AOR = 1.31, 95% CI 1.19–1.45 for LRYGB) compared with the MO group. Mortality was also significantly higher for SO (AOR = 1.65, 95% CI 1.10–2.48 for LSG; AOR = 1.85, 95% CI 1.23–2.80 for LRYGB) and SSO (AOR = 3.30, 95% CI 1.98–5.48 for LSG; AOR = 3.32, 95% CI 1.93–5.73 for LRYGB) compared with the MO group.ConclusionsSO and SSO patients are at increased risk of 30-day morbidity and mortality compared with MO patients. Despite this elevated perioperative risk, the overall risk of these procedures remains low and acceptable especially as bariatric surgery is the durable treatment option for obesity.  相似文献   
77.
78.
Addictive drugs modulate synaptic transmission in the meso‐corticolimbic system by hijacking normal adaptive forms of experience‐dependent synaptic plasticity. Psychostimulants such as METH have been shown to affect hippocampal synaptic plasticity, albeit with a less understood synaptic mechanism. METH is one of the most addictive drugs that elicit long‐term alterations in the synaptic plasticity in brain areas involved in reinforcement learning and reward processing. Dopamine transporter (DAT) is one of the main targets of METH. As a substrate for DAT, METH decreases dopamine uptake and increases dopamine efflux via the transporter in the target brain regions such as nucleus accumbens (NAc) and hippocampus. Due to cross talk between NAc and hippocampus, stimulation of NAc has been shown to alter hippocampal plasticity. In this study, we tested the hypothesis that manipulation of glutamatergic and GABA‐ergic systems in the shell‐NAc modulates METH‐induced enhancement of long term potentiation (LTP) in the hippocampus. Rats treated with METH (four injections of 5 mg/kg) exhibited enhanced LTP as compared to saline‐treated animals. Intra‐NAc infusion of muscimol (GABA receptor agonist) decreased METH‐induced enhancement of dentate gyrus (DG)‐LTP, while infusion of AP5 (NMDA receptor antagonist) prevented METH‐induced enhancement of LTP. These data support the interpretation that reducing NAc activity can ameliorate METH‐induced hippocampal LTP through a hippocampus‐NAc‐VTA circuit loop. Synapse 70:325–335, 2016 . © 2016 Wiley Periodicals, Inc.  相似文献   
79.
Late onset Alzheimer's disease (LOAD) is a non-familial, progressive neurodegenerative disease and the most prominent form of dementia in the elderly. Accumulating evidence suggests that LOAD not only results from the combined effects of variation in a number of genes and environmental factors, but also from epigenetic abnormalities such as histone modifications or DNA methylation. In comparison to monogenic diseases, LOAD exhibits numerous anomalies that suggest an epigenetic component in disease etiology. Evidence against a monogenic course and for an epigenetic component include: 1) the dominance of sporadic cases over familial ones and the low estimated concordance rates for monozygotic twins; 2) gender specific susceptibility and course of disease; 3) parent-of-origin effects, and late age of onset; 4) brain chromatin abnormalities, non-Mendelian inheritance patterns, and atypical levels of folate and homocysteine; and 5) monoallelic expression patterns of susceptibility genes [1]. The epigenome is particularly susceptible to deregulation during early embryonic and neonatal periods and thus disturbances during these periods can have latent lasting effects. The Latent Early-life Associated Regulation (LEARn) model attempts to explain these consequences from a brain specific point of view. In the present review we present the evidence that support the role of epigenetics in the development of AD and explore the potential pathways and mechanisms that may be involved.  相似文献   
80.
Alzheimer's disease (AD) is a leading cause of aging related dementia and has been extensively studied by several groups around the world. A general consensus, based on neuropathology, genetics and cellular and animal models, is that the 4 kDa amyloid β protein (Aβ) triggers a toxic cascade that induces microtubule-associated protein τ (MAPT) hyperphosphorylation and deposition. Together, these lesions lead to neuronal dysfunction and neurodegeneration, modeled in animals, that ultimately causes dementia. Genetic studies show that a simple duplication of the Aβ precursor (APP) gene, as occurs in Down syndrome (trisomy 21), with a 1.5-fold increase in expression, can cause dementia with the complete AD associated neuropathology. The most fully characterized form of AD is early onset familial AD (FAD). Unfortunately, by far the most common form of AD is late onset AD (LOAD). FAD has well-identified autosomally dominant genetic causes, absent in LOAD. It is reasonable to hypothesize that environmental influences play a much stronger role in etiology of LOAD than of FAD. Since AD pathology in LOAD closely resembles FAD with accumulation of both Aβ and MAPT, it is likely that the environmental factors foster accumulation of these proteins in a manner similar to FAD mutations. Therefore, it is important to identify environmentally driven changes that "phenocopy" FAD in order to find ways to prevent LOAD. Epigenetic changes in expression are complex but stable determinants of many complex traits. Some aspects are regulated by prenatal and early post-natal development, others punctuate specific periods of maturation, and still others occur throughout life, mediating predictable changes that take place during various developmental stages. Environmental agents such as mercury, lead, and pesticides can disrupt the natural epigenetic program and lead to developmental deficits, mental retardation, feminization, and other complex syndromes. In this review we discuss latent early- life associated regulation (LEARn), where apparently temporary changes, induced by environmental agents, become latent and present themselves again at maturity or senescence to increase production of Aβ that may cause AD. The model provides us with a novel direction for identifying potentially harmful agents that may induce neurodegeneration and dementia later in life and provides hope that we may be able to prevent age-related neurodegenerative disease by "detoxifying" our environment.  相似文献   
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