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81.
Summary. Fifty-six asthmatics from an asthma ward or from an asthma out-patient clinic were challenged with two low concentrations (0–03 and 0–012 mg) of metacholine chloride in order to assess the relationship between pronounced hyper-responsiveness and asthma severity in a clinical setting. Only inhaled bronchodilators were stopped before challenge. Asthma severity was assessed retrospectively and prospectively on the basis of treatment, number of days in hospital, intensive care, number of emergency visits and days on sick-leave. The results show that pronounced hyper-responsiveness (n= 28) is not associated with asthma severity. It is concluded that a single simplified test of pronounced bronchial hyper-responsiveness, performed without taking into consideration the actual state of the disease and without stopping all medication, is of no help in identifying the patients with the clinically most severe asthma and worst prognosis.,  相似文献   
82.
Abstract: Studies on the circadian rhythm of urine excretion in healthy men have demonstrated that the maximal urine flow occurs in the early afternoon and the minimal around midnight. In this study, an abnormality in the variation of urine volume was found in parkinsonian patients. Urine samples were collected during daytime (9:00–21:00) and nighttime (21:00–9:00). Fifteen healthy control subjects were examined and found to excrete 60% during the daytime and 40% during the nighttime of the total urine volume. Sixteen parkinsonian patients excreted 43% during the daytime and 57% during the nighttime. In contrast to the control subjects, the parkinsonian patients excreted a smaller volume of their urine during the daytime than during the nighttime. This finding might be related to the degeneration of dopaminergic and/or nondopaminergic neurons in the brain which control urinary excretion.  相似文献   
83.
Introduction: Asthma mortality has declined overall because of a range of public health initiatives. In western countries, the majority of asthma deaths now occur in people over the age of 50. The reasons for the poorer response of older age groups to public health asthma initiatives are not known. Objectives: We undertook a study to investigate the disease perspectives of older people with asthma and barriers which may exist and prevent optimal asthma care. Methods: Fifty‐five participants (16 male and 39 female) aged over 50 from an inner city, suburban area and a rural region were recruited. Lung function was measured, and questionnaire data on asthma symptoms, knowledge and control, medication use and respiratory health were collected. Participants were also interviewed in‐depth, and the quantitative and qualitative data were triangulated. Results: Participants with a duration of asthma for >30 years reported significantly fewer symptoms and better quality of life irrespective of asthma severity, indicating less appreciation of symptoms in those with a long asthma duration. Interviews revealed this was related to previous asthma management strategies when treatment options were limited. Participants with a recent diagnosis sought understanding of asthma and the reason for their illness. Initiatives to improve asthma care in older people need to reflect these findings. Conclusions: Self‐management strategies for older people need to be tailored according to the time of disease onset and the duration of disease. Please cite this paper as: Goeman DP, O’Hehir RE, Jenkins C, Scharf SL and Douglass JA. ‘You have to learn to live with it’: a qualitative and quantitative study of older people with asthma. The Clinical Respiratory Journal 2007; 1:99–105.  相似文献   
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OBJECTIVE: Cough variant asthma and atopic cough are different clinical manifestations of eosinophilic airway inflammation presenting with isolated chronic non-productive cough. The aim of this study was to examine the longitudinal change in pulmonary function in cough variant asthma and atopic cough. METHODS: Longitudinal change in FEV1 was prospectively examined in 20 patients with cough variant asthma, 14 patients with atopic cough and 271 asymptomatic healthy subjects. All were lifetime non-smokers. Of the 20 cough variant asthma patients, 13 were taking long-term inhaled corticosteroid therapy (ICS) (beclomethasone dipropionate 615 +/- 58 micro g/day) and the other seven were not. Spirometry was taken at first visit, after cough was almost completely relieved on therapy, and at least once every year for 5 or more years afterwards. RESULTS: The slope of longitudinal change in FEV1 was not significantly different among cough variant asthma patients (- 0.029 +/- 0.007/year), atopic cough patients (- 0.021 +/- 0.022/year) and asymptomatic subjects (- 0.028 +/- 0.002 L/year). In patients with cough variant asthma, the slope in patients not taking inhaled corticosteroids (ICS) was 0.032 +/- 0.007 L/year, which was not significantly different from that in patients taking ICS (- 0.027 +/- 0.010 L/year). CONCLUSION: Pulmonary function decline is not greater in cough variant asthma than atopic cough and the normal population, and long-term ICS has no effect on the decline in cough variant asthma.  相似文献   
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吴新英  马中富 《华夏医学》2003,16(2):288-288,F003
支气管哮喘是常见病和多发病,多种细胞因子参与了支气管哮喘的发病过程。发作期支气管哮喘患者血清可溶性白细胞介素—2受体(SIL—2R)水平明显增高。本文就这方面的进展作一综述。  相似文献   
88.
Hexobarbital (HB) concentrations were determined in plasma and saliva of 8 healthy subjects, following oral administration of 500 mg HB-Na. Mean plasma half-lives were 3.2 +/- 0.1 h, and salivary half-lives 3.3 +/- 0.2 h. Mean plasma clearance was 22.9 +/- 2.3 1 h-1. There was a linear relationship between HB concentrations in saliva and plasma (r = 0.92). Mean salivary levels were 34 per cent of plasma levels. Salivary pH was constant throughout the experiment, 7.06 +/- 0.09. There was an inconsistent tendency of the saliva over plasma ratios to increase as a function of time. The percentage of protein binding calculated from saliva over plasma ratios was in reasonable agreement with in vitro data of equilibrium dialysis, 64.1 +/- 2.6 per cent and 65.9 +/- 0.8 per cent, respectively. The experiment was repeated in 4 subjects, and considerable intraindividual differences were shown to exist in saliva over plasma ratio, half-lives, and protein binding. It was concluded that HB elimination half-lives can relatively accurately be determined from salivary concentrations. Oral plasma clearance can only be estimated if the individual saliva over plasma ratios are known; this would require the taking of at least one blood sample during the experiment. When employing HB as a model substrate for drug metabolizing enzyme activity in vivo, the determination of its pharmacokinetic parameters, particularly oral plasma clearance as a reflection of cytochrome P-450 activity, cannot be achieved by taking saliva samples only.  相似文献   
89.
Summary Slower drug absorption at night can leave residual drug from an evening dose of a sustained-release product remaining to be absorbed at the time of the next morning's dose, thereby giving higher plasma concentrations of the drug during the day than the night.When a capsule product releasing theophylline over 12 h after a morning dose was given repetitively at 8 a.m. and 8 p.m. for 4 days, daytime plasma concentrations from 4 h to 8 h after the dose were about 40% greater than corresponding night-time concentrations, and the mean steady-state concentration during the night-time interval was only 81% of that during the daytime interval.Altering the regimen to one capsule at 12 noon and one at 10 p.m. eliminated all significant differences between a.m. and corresponding p.m. plasma concentrations of theophylline and between the mean steady-state concentrations for each of the interdose intervals within a day.  相似文献   
90.
BACKGROUND: Microbial intestinal colonization in early in life is regarded to play a major role for the maturation of the immune system. Application of non-pathogenic probiotic bacteria during early infancy might protect from allergic disorders but underlying mechanisms have not been analysed so far. OBJECTIVE: The aim of the current study was to investigate the immune effects of oral application of probiotic bacteria on allergen-induced sensitization and development of airway inflammation and airway hyper-reactivity, cardinal features of bronchial asthma. METHODS: Newborn Balb/c mice received orally 10(9) CFU every second day either Lactobacillus rhamnosus GG or Bifidobacterium lactis (Bb-12) starting from birth for consecutive 8 weeks, during systemic sensitization (six intraperitoneal injections, days 29-40) and airway challenge (days 54-56) with ovalbumin. RESULTS: The administration of either Bb-12 or LGG suppressed all aspects of the asthmatic phenotype: airway reactivity, antigen-specific immunoglobulin E production and pulmonary eosinophilia (mean: 137 vs. 17 and 13 cellsx10(3)/mL, respectively). Antigen-specific recall proliferation by spleen cells and T-helper type 2 cytokine production (IL-4, IL-5 and IL-10) by mesenteric lymph node cells also showed significant reduction, while TGF production remained unchanged. Oral LGG administration particularly suppressed allergen-induced proliferative responses and was associated with an increase in numbers of TGF-beta-secreting CD4+/CD3+ T cells in mesenteric lymph nodes (6.5, 16.7%) as well as nearly 2-fold up-regulation of Foxp3-expressing cells in peribronchial lymph nodes. CONCLUSIONS: Neonatal application of probiotic bacteria inhibits subsequent allergic sensitization and airway disease in a murine model of asthma by induction of T regulatory cells associated with increased TGF-beta production.  相似文献   
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