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41.
Electroacupuncture (EA) has been shown to reduce blood lipid level and improve cerebral ischemia in rats with hyperlipemia complicated by cerebral ischemia. However, there are few studies on the results and mechanism of the effect of EA in reducing blood lipid level or promoting neural repair after stroke in hyperlipidemic subjects. In this study, EA was applied to a rat model of hyperlipidemia and middle cerebral artery thrombosis and the condition of neurons and astrocytes after hippocampal injury was assessed. Except for the normal group, rats in other groups were fed a high-fat diet throughout the whole experiment. Hyperlipidemia models were established in rats fed a high-fat diet for 6 weeks. Middle cerebral artery thrombus models were induced by pasting 50% FeCl3 filter paper on the left middle cerebral artery for 20 minutes on day 50 as the model group. EA1 group rats received EA at bilateral ST40 (Fenglong) for 7 days before the thrombosis. Rats in the EA1 and EA2 groups received EA at GV20 (Baihui) and bilateral ST40 for 14 days after model establishment. Neuronal health was assessed by hematoxylin-eosin staining in the brain. Hyperlipidemia was assessed by biochemical methods that measured total cholesterol, triglyceride, low-density lipoprotein and high-density lipoprotein in blood sera. Behavioral analysis was used to confirm the establishment of the model. Immunohistochemical methods were used to detect the expression of glial fibrillary acidic protein and nerve growth factor in the hippocampal CA1 region. The results demonstrated that, compared with the model group, blood lipid levels significantly decreased, glial fibrillary acidic protein immunoreactivity was significantly weakened and nerve growth factor immunoreactivity was significantly enhanced in the EA1 and EA2 groups. The repair effect was superior in the EA1 group than in the EA2 group. These findings confirm that EA can reduce blood lipid, inhibit glial fibrillary acidic protein expression and promote nerve growth factor expression in the hippocampal CA1 region after hyperlipidemia and middle cerebral artery thrombosis. All experimental procedures and protocols were approved by the Animal Use and Management Committee of Beijing University of Chinese Medicine, China (approval No. BUCM-3-2018022802-1002) on April 12, 2018.

Chinese Library Classification No. R459.9; R363; R364  相似文献   
42.
Brain metastases are a major cause of melanoma-related mortality and morbidity. We undertook whole-exome sequencing of 50 tumours from patients undergoing surgical resection of brain metastases presenting as the first site of visceral disease spread and validated our findings in an independent dataset of 18 patients. Brain metastases had a similar driver mutational landscape to cutaneous melanomas in TCGA. However, KRAS was the most significantly enriched driver gene, with 4/50 (8%) of brain metastases harbouring non-synonymous mutations. Hotspot KRAS mutations were mutually exclusive from BRAFV600, NRAS and HRAS mutations and were associated with a reduced overall survival from the resection of brain metastases (HR 10.01, p = 0.001). Mutations in KRAS were clonal and concordant with extracranial disease, suggesting that these mutations are likely present within the primary. Our analyses suggest that KRAS mutations could help identify patients with primary melanoma at higher risk of brain metastases who may benefit from more intensive, protracted surveillance.Subject terms: CNS cancer, Metastasis, Melanoma, Tumour biomarkers, Cancer  相似文献   
43.
BACKGROUND AND PURPOSE:Little is known about microstructural development of cerebellar white matter in vivo. This study aimed to investigate developmental changes of the cerebellar peduncles in second- and third-trimester healthy fetuses using motion-corrected DTI and tractography.MATERIALS AND METHODS:3T data of 81 healthy fetuses were reviewed. Structural imaging consisted of multiplanar T2-single-shot sequences; DTI consisted of a series of 12-direction diffusion. A robust motion-tracked section-to-volume registration algorithm reconstructed images. ROI-based deterministic tractography was performed using anatomic landmarks described in postnatal tractography. Asymmetry was evaluated qualitatively with a perceived difference of >25% between sides. Linear regression evaluated gestational age as a predictor of tract volume, ADC, and fractional anisotropy.RESULTS:Twenty-four cases were excluded due to low-quality reconstructions. Fifty-eight fetuses with a median gestational age of 30.6 weeks (interquartile range, 7 weeks) were analyzed. The superior cerebellar peduncle was identified in 39 subjects (69%), and it was symmetric in 15 (38%). The middle cerebellar peduncle was identified in all subjects and appeared symmetric; in 13 subjects (22%), two distinct subcomponents were identified. The inferior cerebellar peduncle was not found in any subject. There was a significant increase in volume for the superior cerebellar peduncle and middle cerebellar peduncle (both, P < .05), an increase in fractional anisotropy (both, P < .001), and a decrease in ADC (both, P < .001) with gestational age. The middle cerebellar peduncle had higher volume (P < .001) and fractional anisotropy (P = .002) and lower ADC (P < .001) than the superior cerebellar peduncle after controlling for gestational age.CONCLUSIONS:A robust motion-tracked section-to-volume registration algorithm enabled deterministic tractography of the superior cerebellar peduncle and middle cerebellar peduncle in vivo and allowed characterization of developmental changes.

In the second half of pregnancy, the cerebellum is growing rapidly and is extremely vulnerable.1 Despite the increasingly recognized association of antenatal and perinatal cerebellar injury with adverse motor and neurologic outcomes later in life,2-5 little is known about normal cerebellar developmental in the later part of gestation, in particular with regard to changes in microstructure. In fact, most existing fetal MR imaging data addresses primarily changes in cerebellar volume with gestational age (GA) or changes in volume and their association with specific diseases such as congenital heart disease.6-8In vivo evaluation of cerebellar microstructure using fetal MR imaging has been limited by the technical challenges related to imaging the gravid abdomen, particularly patient motion. However, data from ex vivo MR imaging studies are promising. For instance, Takahashi et al9,10 performed high-resolution ex vivo DTI of fetal specimens and demonstrated the feasibility of using tractography to outline the cerebellar peduncles prenatally. Even though tractography of the cerebellar peduncles has been sporadically reported in vivo in technical articles or general review articles on fetal DTI,11 the GA-related microstructural changes that occur in the cerebellar peduncles in the second half of pregnancy remain largely unexplored.Recent advances in hardware and software have improved fetal MR imaging substantially. The use of 3T magnets, which have been shown to be safe, results in improvement of the SNR and spatial resolution, which is advantageous to image the small structures of the fetal brain.12,13 In addition, postprocessing algorithms that enable reconstruction of motion-corrected fetal DTI data are increasingly available and have been used by several groups to characterize the development of the supratentorial white matter tracts in vivo.14-16 We hypothesize that fetal DTI performed at 3T and processed with a robust section-to-volume motion-correction and registration14 algorithm will enable tractography of the cerebellar peduncles in fetuses in the second and third trimesters of pregnancy. We aimed to characterize fetal cerebellar tract microstructure and to investigate tract-specific developmental changes.  相似文献   
44.
BACKGROUND AND PURPOSE:Postprocedural dual-antiplatelet therapy is frequently withheld after emergent carotid stent placement during stroke thrombectomy. We aimed to assess whether antiplatelet regimen variations increase the risk of stent thrombosis beyond postprocedural day 1.MATERIALS AND METHODS:Retrospective review was undertaken of all consecutive thrombectomies for acute stroke with tandem lesions in the anterior circulation performed in a single comprehensive stroke center between January 9, 2011 and March 30, 2020. Patients were included if carotid stent patency was confirmed at day 1 postprocedure. The group of patients with continuous dual-antiplatelet therapy from day 1 was compared with the group of patients with absent/discontinued dual-antiplatelet therapy.RESULTS:Of a total of 109 tandem lesion thrombectomies, 96 patients had patent carotid stents at the end of the procedure. The early postprocedural stent thrombosis rate during the first 24 hours was 14/96 (14.5%). Of 82 patients with patent stents at day 1, in 28 (34.1%), dual-antiplatelet therapy was either not initiated at day 1 or was discontinued thereafter. After exclusion of cases without further controls of stent patency, there was no significant difference in the rate of subacute/late stent thrombosis between the 2 groups: 1/50 (2%) in patients with continuous dual-antiplatelet therapy versus 0/22 (0%) in patients with absent/discontinued dual-antiplatelet therapy (P = 1.000). In total, we observed 88 patient days without any antiplatelet treatment and 471 patient days with single antiplatelet treatment.CONCLUSIONS:Discontinuation of dual-antiplatelet therapy was not associated with an increased risk of stent thrombosis beyond postprocedural day 1. Further studies are warranted to better assess the additional benefit and optimal duration of dual-antiplatelet therapy after tandem lesion stroke thrombectomy.

In around 15% of endovascular procedures for anterior circulation stroke,1 there is a tight stenosis or occlusion of the cervical carotid artery in addition to the intracranial artery occlusion. The optimal endovascular management of tandem lesions has yet to be defined; however, there is mounting evidence2,3 that emergent stent placement in the carotid artery associated with at least 1 antiplatelet agent could lead to better recanalization rates and improved clinical outcomes. A more definitive answer should be provided by the Thrombectomy In TANdem lesions (TITAN) randomized multicenter trial,4 designed to assess the safety and efficacy of emergent internal carotid artery stent placement in tandem lesion thrombectomy. This study recently enrolled the first patient in early 2020.In patients undergoing emergent carotid stent placement, there is no consensus regarding the optimal periprocedural antiplatelet therapy. Many groups5,6 chose to avoid dual-antiplatelet therapy (DAPT) during the first 24 hours in an attempt to reduce the risk of hemorrhagic transformation. Conversely, less aggressive antiplatelet regimens might increase the risk of carotid stent thrombosis.Stent thrombosis was recently identified as a predictor of unfavorable clinical outcome.7,8 To date, available data regarding stent patency rates remain scarce. Most case series of endovascular management for tandem lesions5,9-11 do not report postprocedural stent patency, while some publications12-15 offer partial data for a subgroup of patients for whom carotid imaging controls were available. Reported rates of stent thrombosis ranged between 1.2% and 22.0%.6-8,12-14,16,17To date, no study has attempted to differentiate between early (first 24 hours) and subacute/late postprocedural stent thrombosis. During the first 24 hours, protection against stent thrombosis is conferred by antiplatelet agents administered during the procedure (periprocedural antiplatelets). Beyond 24 hours, the recommended antiplatelet regimen is DAPT for 4–12 weeks,9,17 but in reality, antiplatelets are often tailored in view of neurological and extra-neurological hemorrhagic events. It is currently unknown whether discontinuation of DAPT is associated with an increased risk of late stent thrombosis.Thus, we aimed to describe the variations in the postprocedural antiplatelet regimen in a large consecutive cohort of tandem lesion thrombectomies with emergent carotid artery stent placement and to assess whether discontinuation of DAPT was associated with an increased risk of carotid stent thrombosis.  相似文献   
45.
BACKGROUND AND PURPOSE:Transradial access for neurointerventional procedures has been proved a safer and more comfortable alternative to femoral artery access. We present our experience with transradial (distal radial/anatomic snuffbox and radial artery) access for treatment of intracranial aneurysms using all 3 FDA-approved flow diverters.MATERIALS AND METHODS:This was a high-volume, dual-center, retrospective analysis of each institution’s data base between June 2018 and June 2020 and a collection of all patients treated with flow diversion via transradial access. Patient demographic information and procedural and radiographic data were obtained.RESULTS:Seventy-four patients were identified (64 female patients) with a mean age of 57.5 years with a total of 86 aneurysms. Most aneurysms were located in the anterior circulation (93%) and within the intracranial ICA (67.4%). The mean aneurysm size was 5.5 mm. Flow diverters placed included the Pipeline Embolization Device (Flex) (PED, n = 65), the Surpass Streamline Flow Diverter (n = 8), and the Flow-Redirection Endoluminal Device (FRED, n = 1). Transradial access was successful in all cases, but femoral crossover was required in 3 cases (4.1%) due to tortuous anatomy and inadequate support of the catheters in 2 cases and an inability to navigate to the target vessel in a patient with an aberrant right subclavian artery. All 71 other interventions were successfully performed via the transradial approach (95.9%). No access site complications were encountered. Asymptomatic radial artery occlusion was encountered in 1 case (3.7%).CONCLUSIONS:Flow diverters can be successfully placed via the transradial approach with high technical success, low access site complications, and a low femoral crossover rate.

The transradial access (TRA), including distal radial artery (dRA) access in the anatomic snuffbox and radial artery (RA) access at the palmar surface of the wrist, is being increasingly used as primary vascular access for neurointerventional procedures. In prior years, large randomized trials in the field of interventional cardiology and more recent articles in neurointerventional surgery have shown higher patient preference for the TRA, cost reduction, as well as lower morbidity and mortality compared with the traditional transfemoral access (TFA).1-11 Reduction in access site complications has been a particular advantage of wrist over femoral access and is an important consideration for vascular access choice in the treatment of intracranial aneurysms using flow diversion. Patients undergoing flow diversion are required to take dual-antiplatelet agents and receive heparin during the procedure, all of which increase the risk of bleeding from the access site.12 Also, flow diverters (FDs) may require large-bore catheter assemblies for delivery and deployment, which may increase the risk of radial artery occlusion, access site bleeding, or vascular injury.13,14To date, only a limited number of case reports and case series have described the safety and feasibility of TRA for the treatment of intracranial aneurysms using flow diverters.15-22Recently, a large, retrospective multicenter study reported the safety of TRA for flow diversion, showing a lower access site (P = .039) and overall complication rate (P = .035).12 This study, however, did not cover catheter systems, patient functional outcome, and aneurysm occlusion. Here, we report our experience with TRA (dRA [anatomic snuffbox] and RA) for the treatment of intracranial aneurysms using all 3 FDA-approved flow diverters, including technical feasibility, procedural safety, patient outcome, and aneurysm occlusion on follow-up. Additionally, we reviewed the current literature on use of flow diverters via TRA.  相似文献   
46.
BACKGROUND AND PURPOSE:The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.MATERIALS AND METHODS:We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.RESULTS:The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (−5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017–2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017–2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.CONCLUSIONS:Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.

There is much concern regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on the quality of stroke care, including issues with hospital capacity, clinical resource re-allocation, and the safety of patients and clinicians.1,2 Previous reports have shown that there have been substantial decreases in stroke neuroimaging volume during the pandemic.3,4 In addition, acute ischemic infarcts have been found on neuroimaging studies in many hospitalized patients with COVID-19, though the causal relationship is unclear.5,6 Studies like these and other epidemiologic analyses usually rely on the creation of manually curated databases, in which identification of cases can be time-consuming and difficult to update in real-time. One way to facilitate such research is to use natural language processing (NLP), which has shown utility for automated analysis of radiology report data.7 NLP algorithms have been developed previously for the classification of neuroradiology reports for the presence of ischemic stroke findings and acute ischemic stroke subtypes.8,9 Thus, NLP has the potential to facilitate COVID-19 research.In this study, we developed an NLP machine learning model that classifies radiology reports for the presence or absence of acute or subacute ischemic stroke (ASIS), as opposed to chronic stroke. We used this model to quantify the change in ASIS detected on all CT or MR imaging studies performed at a large comprehensive stroke center during the COVID-19 pandemic in the United States. We also evaluated NLP model generalizability and different training strategies using a sample of radiology reports from a second stroke center.  相似文献   
47.

Background

Children have a statutory right to a smoke-free environment, and tobacco control advocates are now considering regulation of smoking behavior in the private sphere. The Norwegian Institute of Public Health has investigated the support for a ban on smoking in cars with children compared to other possible extensions of the tobacco act among the Norwegian public.

Material and methods

A nationwide representative survey (CAWI) of 5543 participants was conducted in 2014–2015. Respondents were asked to consider several possible new tobacco control measures, through selfreported ranking on 5-point scales for each measure. Multiple logistic regression models were applied to control for confounders (i.a. smoking behavior) for the tendency to state full support.

Results

A majority (78 % of all respondents, 61.8% of daily smokers) supported a proposal prohibiting smoking in cars when children are present. This proposal received substantially more support than bans on private balconies, in parks and at public transport stops and work entrances. Full support for the latter proposals varied between 39.9% and 58.1% (between 2.7% and 16.8% among smokers). Differences by smoking status were maintained after multiple controls.

Interpretation

The strong endorsement of the proposal (also provided by the majority of current smokers) suggests high legitimacy and compliance, which means that an implementation could be introduced without serious enforcement problems.  相似文献   
48.
Background:Criteria for diagnosis and compensation of occupational musculoskeletal diseases varies widely between countries as demonstrated by the large differences between countries with comparable economics and social systems (for example, within the European Union). Several countries have a list of occupational diseases and sometimes these lists include diagnostic and attribution criteria, but these criteria are usually not very specific, and they may also be very different.Objectives:The aim of this paper is to explicitly define what are the information needed for an evidence-based diagnosis and attribution of an occupational musculoskeletal disease.Methods:Based on the general framework of evidence-based medicine, a review is presented of the information required to define: - when a musculoskeletal disease is present, according to the best available techniques; - how to define a relevant exposure to biomechanical risk factors, according to the best available techniques.Results:Criteria are presented to combine information regarding the diagnosis of a musculoskeletal disease and exposure to biomechanical risk factors for an evidence-based attribution of the disease to the occupational exposure. The criteria use a probabilistic model that combine epidemiologic and medical findings, workplace exposure assessment, and non-occupational factors evaluation.Discussion:The use of the proposed criteria may improve the process of diagnosis and attribution of an occupational musculoskeletal disease. In addition, it makes possible to associate a probability rank to the attribution and, ultimately, it may improve the overall quality of the decisional process of the occupational physician.Key words: Criteria, occupational disease, musculoskeletal system  相似文献   
49.
ABSTRACT

Language and executive functioning are major impairments in many neurodevelopmental disorders, but little is known about the relations between these constructs, particularly using parent-report. Thus, the current research sought to examine relations between executive function and language in two groups – Down syndrome (DS; n=41; Mage = 11.2) and autism spectrum disorder (ASD; n=91; Mage = 7.7). Results were as follows: in DS, executive function predicted pragmatic, but not structural language after covarying for age, sex, and social functioning; in ASD, executive function predicted both. Findings highlight the interrelatedness of language and executive functioning and may have implications for intervention development.  相似文献   
50.

Background

Various trajectories for lung function and bronchial hyper-reactivity (BHR) from early childhood to adulthood are described, including puberty as a period with excessive lung growth. Bronchiolitis in infancy may be associated with increased risk of developing chronic obstructive pulmonary disease, but the development of respiratory patterns during puberty is poorly characterized for these children. We aimed to study the development and trajectories of lung function and BHR from 11 to 18 years of age in children hospitalized for bronchiolitis in infancy.

Methods

Infants hospitalized for bronchiolitis at the University Hospitals in Stavanger and Bergen, Norway, during 1997-1998, and an age-matched control group, were included in a longitudinal follow-up study and examined at 11 and 18 years of age with spirometry and methacholine provocation test (MPT). The MPT data were managed as dose-response slope (DRS) in the statistical analyses. Changes in lung function and DRS from 11 to 18 years of age were analyzed by generalized estimating equations, including interaction terms.

Results

z-scores for forced vital capacity (FVC), forced expiratory volume in first second (FEV1), FEV1/FVC ratio, and DRS were not different from 11 to 18 years of age in both the post-bronchiolitis and the control group. The trajectories from 11 to 18 years did not differ between the two groups. BHR at age 11 was independently associated with asthma at age 18.

Conclusion

Children hospitalized for bronchiolitis had stable predicted lung function and BHR from 11 to 18 years of age. The lung function trajectories were not different from controls.
  相似文献   
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