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921.
922.
Background Previous studies demonstrated higher mortality for patients with a longer pre-intensive care unit (ICU) hospital length of stay (LOS), in well-resourced settings. Objectives The study aimed to determine the association between pre-ICU hospital LOS and ICU outcomes in a resource-limited setting. We hypothesised that longer pre-ICU hospital LOS would be associated with higher ICU mortality. Methods This was a retrospective cohort study measuring the association between pre-ICU hospital LOS and ICU outcomes using data extracted from a regional hospital ICU in KwaZulu-Natal, South Africa. Consecutive ICU admissions of all patients (medical and surgical) older than 18 years were included during the study period September 2014 to August 2018. A corrected sample size of 2 040 patients was identified. Multivariable logistic regression was used to assess the primary outcome of ICU mortality, and multivariable Cox proportional hazard regression was used for the secondary outcome of ICU LOS. Results The median pre-ICU hospital LOS was 1 day (interquartile range (IQR) 0 - 2 days). The median length of ICU stay was 2.4 days (IQR 1.1 - 4.8 days) and the observed ICU mortality was 16% (n=327/2 040). Pre-ICU hospital LOS was not associated with ICU mortality in the unadjusted (odds ratio (OR) 1.00; 95% confidence interval (CI) 0.98 - 1.02; p=0.68; n=2 040) and fully adjusted logistic regression models (OR 1.00; 95% CI 0.98 - 1.03; p=0.90; n=1 981) using a complete case analysis for missing patient-level covariates. In Cox proportional hazard models, there was no association between pre-ICU hospital LOS and ICU LOS (hazard ratio 1.00; 95% CI 0.98 - 1.03; p=0.72; n=1 967), including when stratified by admission source. Conclusion Pre-ICU hospital LOS was not associated with either ICU mortality or ICU LOS in a resource-limited setting. Future studies should aim to include multicentre data and evaluate long-term outcomes. Contributions of the study The study was conducted in a resource-limited setting and found no association between prolonged LOS pre-ICU and patient outcomes. Several potential explanations for this observation have been explored. This important subject is pertinent to the appropriate use of limited resources and encourages future studies to evaluate this association and to consider longer-term outcomes (e.g. 30-day mortality) in future findings.  相似文献   
923.
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.  相似文献   
924.
925.
Periorbital hyperpigmentation (POH) is a common dermatological condition that presents as dark periorbital area beneath the lower eyelids, and it is commonly found in females belonging to the age group of 16 to 45 years. The data presented in this review include studies conducted on patients with a clinical/histological diagnosis of POH or melasma. Many diverse topical depigmenting agents comprising an array of naturally obtained actives such as arabinoxylans, α‐arbutin, asiaticoside, azelaic acid, beta‐carotene, boswellic acid, caffeine, chrysin, curcumin, cyanidin‐3‐glucoside, d ‐glucoronic acid, dihydrochalcone, dipalmitoyl‐hydroxyprolene, fucoxanthin, genistein, glabridin, b‐glucogallin, hyaluronic acid, lactic acid, lycopene, niacinamide, pycnogenol, retinol, salidroside, and xymenynic acid demonstrated significant benefits in the management of POH. An exhaustive literature search revealed that other techniques such as blepharoplasty, carboxytherapy, calcium hydroxylapatite fillers, tear trough implant, Q‐switched ruby laser, medicated tattoo, fat transfer, micro‐needling, chemical peels, nitrogen plasma skin regeneration, intense pulsed light, and radiofrequency have been evaluated and reported to be beneficial in the treatment of POH. The use of topical depigmenting agents is the most widely reported method in the clinical management of POH. Of these, α‐arbutin, caffeine, cyanidin‐3‐glucoside, and dihydrochalcone are reported to exhibit significant benefits. Combination products containing a blend of actives are reported to be better than single active containing products. This review aims to provide a comprehensive perspective on the role of several topical actives in the modulation of melanin and tyrosinase biosynthesis pathway involved in the complex pathophysiology of POH. It also presents the advantages of combination products and other alternative therapies used in the management of POH.  相似文献   
926.
927.
Neoplastic or dysplastic neuronal tissue in the brain stem and cerebellum can become epileptogenic in pediatric patients. However, it is unknown whether such tissue may transform intrinsic properties of the human cerebellum, making it capable of generating epileptic population activity. We noninvasively detected epileptiform signals unaveraged in a pediatric patient with epilepsy due to a tumor in the middle cerebellar peduncle. Analysis of generators of the signals revealed that the cerebellum ipsilateral and contralateral to the tumor was the dominant interictal spike generator and could initiate ictal activity, suggesting that human cerebellum may become capable of intrinsically generating epileptic activity. ANN NEUROL 2020;88:418–422.  相似文献   
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929.
The third trimester of pregnancy is a period of rapid development of fiber bundles in the fetal white matter. Using a recently developed motion‐tracked slice‐to‐volume registration (MT‐SVR) method, we aimed to quantify tract‐specific developmental changes in apparent diffusion coefficient (ADC), fractional anisotropy (FA), and volume in third trimester healthy fetuses. To this end, we reconstructed diffusion tensor images from motion corrected fetal diffusion magnetic resonance imaging data. With an approved protocol, fetal MRI exams were performed on healthy pregnant women at 3 Tesla and included multiple (2–8) diffusion scans of the fetal head (1–2 b = 0 s/mm2 images and 12 diffusion‐sensitized images at b = 500 s/mm2). Diffusion data from 32 fetuses (13 females) with median gestational age (GA) of 33 weeks 4 days were processed with MT‐SVR and deterministic tractography seeded by regions of interest corresponding to 12 major fiber tracts. Multivariable regression analysis was used to evaluate the association of GA with volume, FA, and ADC for each tract. For all tracts, the volume and FA increased, and the ADC decreased with GA. Associations reached statistical significance for: FA and ADC of the forceps major; volume and ADC for the forceps minor; FA, ADC, and volume for the cingulum; ADC, FA, and volume for the uncinate fasciculi; ADC of the inferior fronto‐occipital fasciculi, ADC of the inferior longitudinal fasciculi; and FA and ADC for the corticospinal tracts. These quantitative results demonstrate the complex pattern and rates of tract‐specific, GA‐related microstructural changes of the developing white matter in human fetal brain.  相似文献   
930.
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