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41.
ABSTRACT. Subacute thyroiditis is generally believed to be of viral origin, and infection is also suspected of playing a role as a triggering factor in the pathogenesis of autoimmune thyroid diseases. We have measured a broad spectrum of bacterial and viral antibodies in paired sera of 32 patients with thyroid disease of recent onset. The data indicate a preceding infection in 14 (44%) of the patients, enterobacterial in 5, streptococcal in 4 and staphylococcal in 2. A viral infection was suggested in 6 patients, in each case caused by different agents; 3 of them also showed evidence of a bacterial infection. Patients with positive microbial serology were found in all diagnostic groups, including subacute thyroiditis, Graves' disease and Hashimoto's disease. These results suggest an association between a preceding bacterial infection and the development of thyroid disease in some patients.  相似文献   
42.
Patients with chronic obstructive pulmonary disease (COPD) often develop osteoporosis. Many hormones regulate bone metabolism and body composition, and some of them are affected in COPD patients vs controls. In 46 COPD patients, we measured hip neck, total hip, lumbar spine, and whole-body T-score with dual-energy X-ray absorptiometry, parameters of body composition (body mass index [BMI], fat mass index [FMI], and fat-free mass index [FFMI]), and adiponectin, leptin, parathormone, osteocalcin, calcitonin, and insulin-like growth factor I (IGF-I) serum levels and correlated them with COPD stage. Our results suggest that total hip bone mineral density (BMD) is affected by FFMI and COPD stage; lumbar spine BMD is affected by FMI and COPD stage; and whole-body BMD is affected by BMI, COPD stage, and leptin. Adiponectin, parathormone, osteocalcin, calcitonin, and IGF-I levels were not significantly correlated to BMD at any of the measured sites. Our findings are in agreement with the current literature in that a decline in lung function is correlated to a decline in BMD.  相似文献   
43.
The data on long-term application of non-invasive ventilation (NIV) in patients with chronic respiratory failure due to COPD are contradictory. We evaluated the effect of the addition of NIV to optimal treatment for 1 year on the quality of life of stable hypercapnic COPD patients. NIV was offered to 49 of 58 initially enrolled consecutive patients, of whom 22 refused NIV and comprised the standard treatment group whereas 27 received NIV. Quality of life was assessed with the SF-36 questionnaire. Additional measurements included blood gases, pulmonary function tests, dyspnea, daytime sleepiness, exacerbations and hospitalizations. The NIV group showed a significant improvement in quality of life in the third month, both in the Physical (31+/-4 to 38+/-8, p<0.0001) and the Mental Component Summary Score (28+/-7 to 40+/-10, p=0.009), that was maintained until the twelfth month. PaCO2 decreased by the first month in the NIV group (54+/-4.5 to 44.6+/-5.6 mmHg, p<0.0001), and PaO2 rose during the sixth month (58.9+/-5.7 to 64.4+/-6.5 mmHg, p=0.004). Dyspnea and diurnal sleepiness improved significantly. No significant improvements were observed in the control group. Patients on NIV spent less days in the hospital compared to controls. NIV when added to optimal medical treatment has beneficial effects on quality of life in stable hypercapnic COPD patients, with additional improvements in arterial blood gases, dyspnea and daytime sleepiness.  相似文献   
44.
Helicobacter pyloriinfection and respiratory diseases: a review   总被引:2,自引:0,他引:2  
In the past few years, a variety of extradigestive disorders, including cardiovascular, skin, rheumatic and liver diseases, have been associated with Helicobacter pylori (H. pylori) infection. The activation of inflammatory mediators by H. pylori seems to be the pathogenetic mechanism underlying the observed associations. The present review summarizes the current literature, including our own studies, concerning the association between H. pylori infection and respiratory diseases. A small number of epidemiological and serologic, case-control studies suggest that H. pylori infection may be associated with the development of chronic bronchitis. A frequent coexistence of pulmonary tuberculosis and H. pylori infection has also been found. Moreover, recent studies have shown an increased H. pylori seroprevalence in patients with bronchiectasis and in those with lung cancer. On the other hand, bronchial asthma seems not to be related with H. pylori infection. All associations between H. pylori infection and respiratory diseases are primarily based on case-control studies, concerning relatively small numbers of patients. Moreover, there is a lack of studies focused on the pathogenetic link between respiratory diseases and H. pylori infection. Therefore, we believe that larger studies should be undertaken to confirm the observed results and to clarify the underlying pathogenetic mechanisms.  相似文献   
45.
ObjectiveThe effect of IGF-1 in the human pleural permeability and the underlying mechanisms involved were investigated.DesignSpecimens from thoracic surgical patients were mounted in Ussing chambers. Solutions containing IGF-1 (1 nM–100 nM) and IGF-1 Receptor Inhibitor (1 μΜ), amiloride 10 μM (Na+ channel blocker) and ouabain 1 mM (Na+–K+ pump inhibitor) were used in order to investigate receptor and ion transporter involvement respectively. Trans-mesothelial Resistance (RTM) across the pleural membrane was determined as a permeability indicator. Immunohistochemistry for IGF-1 receptors was performed.ResultsIGF-1 increased RTM when added on the interstitial surface for all concentrations (p = .008, 1 nM–100 nM) and decreased it on the mesothelial surface for higher concentrations (p = .046, 100 nM). Amiloride and ouabain inhibited this effect. The IGF-1 Receptor Inhibitor also totally inhibited this effect. Immonuhistochemistry demonstrated the presence of IGF-1 receptors in the pleura.ConclusionsIt is concluded that IGF-1 changes the electrophysiology of the human parietal pleura by hindering the normal ion transportation and therefore the pleural fluid recycling process. This event is achieved after IGF-1 interaction with its receptor which is present in the human pleura.  相似文献   
46.
47.
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency.  相似文献   
48.
Baker  DE; Silver  TM; Coran  AG; McMillin  KI 《Radiology》1986,161(2):341-344
At the authors' medical center, most patients with postappendectomy fluid collections are treated conservatively. Thirty-two (15%) of 216 children underwent postoperative sonography following appendectomies. In ten patients (31%), a total of 16 fluid collections were found on the initial postoperative sonogram. In the seven patients (70%) whose fluid collections were confined to the pelvis, the condition was treated conservatively and it resolved in 2-9 weeks. In three patients, fluid collections required surgical drainage and proved to be abscesses. In two of the three patients, abscesses were multiple and widely distributed in the abdomen, and the patients were clinically ill. The authors conclude that clinically symptomatic fluid collections develop postoperatively in approximately 5% of children who have undergone appendectomy for acute appendicitis and that the size and course of the fluid collection can be objectively monitored using sonography. Such fluid collections confined to the pelvis ultimately resolve with conservative, nonoperative therapy, although resolution may take up to 2 months.  相似文献   
49.
A case of severe photosensitivity in a girl with the Smith–Lemli–Opitz syndrome is reported. Children with this recessively inherited metabolic disorder of cholesterol metabolism present with a variety of congenital abnormalities of the nervous system and internal organs in association with varying degrees of mental retardation. Photosensitivity is a feature which has previously only briefly been mentioned in the literature in association with this syndrome. However, more recently, it has become apparent that photosensitivity is not uncommon among children with the Smith–Lemli–Opitz syndrome, although the nature of the photosensitivity in these patients has remained undefined. Our patient has suffered from sunlight intolerance since early infancy, with redness and pruritus of sun-exposed skin developing within minutes of sun exposure. Monochromator ultraviolet (UV) radiation and visible light testing revealed an immediate and persistent reaction to low-dose UVA at 350 nm, and an abnormal erythemal response to visible light at 400 nm.  相似文献   
50.
Dofetilide may induce aberrant intraventricular conduction due to its Class III effect. This report describes an atrial fibrillation patient in whom intraventricular conduction was studied before and after dofetilide using multiple endocardial recordings. Dofetilide provoked aberrant conduction during atrial fibrillation, and aberrancy could be mimicked with programmed atrial stimulation after restoration of sinus rhythm. However, during right ventricular slimulation, isolated bundle branch reentrant beats were recorded after induction of critical retrograde conduction delays. This occurred in the setting of relatively large differences in refractoriness between the right bundle branch and the right ventricular myocardium. This favored distal retrograde bundle branch block during ventricular extrastimulation, in turn enhancing bundle branch reentry. This potendal proarrhythmic mechanism deserves close attention in the further deveiopmeni of dofetilide and also of other new "pure" Class III agents.  相似文献   
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