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1.
PURPOSE: To study the association between body mass index (BMI) and mortality, and to evaluate the effect of physical activity during leisure time and smoking on this association in a general male population. METHODS: During 1974-1978, all men aged 35-49 yr living in three Norwegian counties were invited to a cardiovascular screening, and 87.1% attended and had their weight and height measured. Men with recognized cardiovascular diseases, diabetes mellitus, or cancer at screening were excluded. The cohort (N = 22,304) was followed for an average of 16.3 yr with respect to total and cause-specific mortality. RESULTS: During follow-up, 1909 men died. We found a J-shaped association between BMI and total mortality, and the form of association was similar for death from cardiovascular diseases. Although not statistically significant, a J-shaped association was also suggested in never-smokers. Irrespective of BMI level, ex- and never-smokers had lower mortality than current smokers. Obese smoking men had a relative risk of dying of 2.01 (95% CI: 1.29-3.11) compared with obese never-smokers, and a relative risk of 4.55 (95% CI: 3.34-6.20) compared with normal weight never-smokers (BMI 22-24.9 kg x m(-2)). Within each category of physical activity during leisure time, obese men had a similar increased relative risk of death compared with normal-weight individuals. However, the U- to J-shaped association between BMI and mortality seemed to disappear by increasing level of physical activity, but this finding was not significant. CONCLUSION: This study suggests a J-shaped association between BMI and total mortality, also when stratified on smoking habits and physical activity. The suggested linear trend in the most physical active men needs to be reassessed.  相似文献   
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OBJECTIVE: Three-dimensional (3-D) ultrasound is an intraoperative imaging modality used in neuronavigation as an alternative to magnetic resonance imaging (MRI). This article summarizes 4 years of clinical experience in the use of intraoperative 3-D ultrasound integrated into neuronavigation for guidance in brain tumor resection. METHODS: Patients were selected for inclusion in the study on the basis of the size and location of their lesion. Preoperative 3-D MRI data were registered and used for planning as in other conventional neuronavigation systems. Intraoperative 3-D ultrasound images were acquired three to six times, and tumor resection was guided on the basis of these updated 3-D images. RESULTS: Intraoperative 3-D ultrasound represents a good solution to the problem of brain shift in neuronavigation because it easily provides an updated, and hence more accurate, map of the patient's true anatomy in all phases of the operation. Ultrasound makes it possible to follow the progression of the operation, and it improves the radicality of tumor resection by detecting tumor tissue that would remain if the imaging technology had not been used (in 53% of the cases). Integration of 3-D ultrasound with navigation technology solves the orientation problem experienced previously with two-dimensional ultrasound in neurosurgery. The technology makes it possible to directly compare intraoperative ultrasound and MRI data regarding visualization of the lesion. Ultrasound image quality is useful for guiding surgical procedures. CONCLUSION: Intraoperative 3-D ultrasound seems to provide a time- and cost-effective way to update high-quality 3-D maps used in neuronavigation.  相似文献   
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Background  

In the treatment of chronic back pain, cognitive methods are attracting increased attention due to evidence of effectiveness similar to that of traditional therapies. The purpose of this study was to compare the effectiveness of performing a cognitive intervention based on a non-injury model with that of a symptom-based physical training method on the outcomes of low back pain (LBP), activity limitation, LBP attitudes (fear-avoidance beliefs and back beliefs), physical activity levels, sick leave, and quality of life, in chronic LBP patients.  相似文献   
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Abstract

We evaluated the operative outcome in 22 consecutive patients who underwent microvascular decompression (MVO) of the intracranial portion of the cochlear nerve to relieve incapacitating tinnitus and related it to preoperative findings. The patients were selected for operation from the following criteria: severe tinnitus with sensorineural hearing loss and/or changes in brainstem auditory evoked potentials (BAEPs). Fifty percent had unilateral tinnitus. Before operation, 77 patients (77%) had sensorineural hearing loss in their affected ear. BAEPs were abnormal in 27 patients (95%) and acoustic middle ear reflex response was abnormal in six patients (27%). Vascular compression of the cochlear nerve was found in all patients during the operation. After the operation, 33% had relief of their tinnitus (two patients were totally free of tinnitus and five were markedly improved). Eight patients were slightly improved (38%), and the tinnitus did not change in four patients; two patients (70%) became worse. Of the patients with unilateral tinnitus, 63% had relief oftheir tinnitus. In one patient hearing was noticeably improved after the operation. Five patients (23%) had mild to moderate sensorineural hearing loss due to the operation. No other complications were detected. [Neural Res 1998; 20: 242-248]  相似文献   
6.
In this study of cancer in offspring we demonstrate that factors linked to horticulture and use of pesticides are associated with cancer at an early age, whereas factors in animal husbandry, in particular poultry farming, are associated with cancers in later childhood and young adulthood. Incident cancer was investigated in offspring born in 1952–1991, to parents identified as farm holders in agricultural censuses in Norway in 1969–1989. In the follow-up of 323,292 offspring for 5.7 million person-years, 1,275 incident cancers were identified in the Cancer Registry for 1965–1991. The standardized incidence for all cancers was equal to the total rural population of Norway, but cohort subjects had an excess incidence of nervous-system tumours and testicular cancers in certain regions and strata of time that could imply that specific risk factors were of importance. Classification of exposure indicators was based on information given at the agricultural censuses. Risk factors were found for brain tumours, in particular non-astrocytic neuroepithelial tumours: for all ages, pig farming tripled the risk [rate ratio (RR), 3.11; 95% confidence interval (CI), 1.89–5.13]; indicators of pesticide use had an independent effect of the same magnitude in a dose-response fashion, strongest in children aged 0 to 14 years (RR, 3.37; 95% CI, 1.63–6.94). Horticulture and pesticide indicators were associated with all cancers at ages 0 to 4 years, Wilms' tumour, non-Hodgkin's lymphoma, eye cancer and neuroblastoma. Chicken farming was associated with some common cancers of adolescence, and was strongest for osteosarcoma and mixed cellular type of Hodgkin's disease. The main problem in this large cohort study is the crude exposure indicators available; the resulting misclassification is likely to bias any true association towards unity. © 1996 Wiley-Liss, Inc.  相似文献   
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The Göttingen minipig is being used increasingly in biomedical research. The anatomical structure of the porcine peripheral nervous system has been extensively characterized, but no equivalent to the dermatome map, which is so valuable in human neurophysiological research, has been created. We characterized the medullar segmental skin and muscle innervations of the minipig hind body, using neurophysiological methodology. Six adult minipigs underwent unilateral laminectomy from L2 to S3, exposing the nerve roots. The skin of the hind part of the body was divided into 36 predefined fields, based on anatomical landmarks for consistent reproducibility. We recorded the evoked potential in each exposed nerve root L2‐S3 for cutaneous stimulation of each skin field, mapping the sensory innervation of the entire hind body. We subsequently recorded the motor response in seven predefined muscles during sequential stimulation of the L2‐S3 nerve roots. We obtained a clear sensory evoked potential in the nerve roots during stimulation of the skin fields, allowing us to map the sensory innervation of the minipig hind body. Neurophysiological data from skin stimulation and muscle recordings enabled us to map the sensory innervation of the Göttingen minipig hind body and provide information about muscular innervation. The skin fields were sensory innervated by more than one root. The muscles each had one dominant root with minor contribution from neighboring roots. This is consistent with experimental data from human studies.  相似文献   
9.
Summary Muscle biopsies from eight cases of acute juvenile diabetes (a few weeks after the beginning of the disease) revealed well marked degenerative changes combined with vigorous regeneration of the terminal neuromuscular apparatus. This observation is in accordance with previous demonstrations of neurophysiological disturbances at this early stage of diabetes.
Morphologische Anomalien der neuromuskulären Endplatte bei frisch entdeckten juvenilen Diabetikern
Zusammenfassung Muskelbiopsien von 8 Patienten mit akutem juvenilem Diabetes (einige Wochen nach Krankheitsausbruch) zeigten ausgeprägte degenerative Veränderungen mit kräftigen Regenerationserscheinungen an der neuromuskulären Endplatte. Diese Befunde stimmen mit früher mitgeteilten Beobachtungen neurophysiologischer Störungen dieses Frühstadiums des Diabetes überein.

Anomalies morphologiques de l'appareil neuro-musculaire terminal dans le diabète juvénile récent
Résumé Dans huit cas de diabete juvénile aigu (quelques semaines après le début de la maladie) des biopsies musculaires ont révélé des modifications dégénératives bien marquées, associées á une puissante régénération de l'appareil neuro-musculaire terminal. Cette observation est en accord avec les démonstrations précédentes de troubles neurophysiologiques à ce stade précoce du diabète.
  相似文献   
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