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排序方式: 共有1038条查询结果,搜索用时 15 毫秒
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Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
3.
Dennis S Poe 《Otology & neurotology》2007,28(5):668-677
OBJECTIVE: The patulous eustachian tube (ET) seems to be caused by a longitudinal concave defect in the mucosal valve at the superior aspect of its anterolateral wall and causes troublesome autophony of one's own voice and breathing sounds. Patulous ET reconstruction was evaluated to analyze whether submucosal graft implantation to fill in the concavity within the patulous tubal valve may produce lasting relief of symptoms. STUDY DESIGN: Prospective trial. SETTING: Tertiary referral center, ambulatory surgery. PATIENTS: Fourteen ETs in 11 adults with 1 or more years of confirmed continuous patulous ET symptoms refractory to medical care. INTERVENTION: Endoluminal patulous ET reconstruction was performed in 14 separate cases using a combined endoscopic transnasal and transoral approach under general anesthesia. A submucosal flap was raised along the anterolateral wall of the tubal lumen up to the valve and mobilized superiorly off of the basisphenoid. The pocket was filled with autologous cartilage graft or Alloderm implant, restoring the normal convexity and competence to the mucosal lumen valve. MAIN OUTCOME MEASURE: Autophony symptoms were scored as 1) complete relief; 2) significant improvement, satisfied; 3)significant improvement, dissatisfied; 4) unchanged; or 5)worse. RESULTS: All 14 cases reported immediate complete relief of autophony. Results with an average follow-up of 15.8 months are as follows: 1 (7%) case had complete relief; 5 (36%) had significant improvement, satisfied; 7 (50%) had significant improvement, dissatisfied; and 1 (7%) was unchanged. There were no complications. Correlation between patulous ET and other conditions was strongest with previous tubal dysfunction. Autophony of voice, but not breathing sounds, was also found to be experienced by 17 (94%) of 18 patients with superior semicircular canal dehiscence syndrome and could be easily mistaken for patulous ET autophony. CONCLUSION: Patulous ET seems to be caused by a concave defect in the tubal valve's anterolateral wall. Submucosal graft implantation to restore the normal convexity to the valve wall seems to provide lasting relief of symptoms. Long-term study is needed. It is important to differentiate between the autophony of semicircular canal dehiscence syndrome and patulous ET. 相似文献
4.
Charlotte V. Hobbs Jan Drobeniuc Theresa Kittle John Williams Paul Byers Panayampalli S. Satheshkumar Kengo Inagaki Meagan Stephenson Sara S. Kim Manish M. Patel Brendan Flannery CDC COVID- Response Team CDC COVID- Response Team Bailey Alston Shanna J. Bolcen Darbi Boulay Peter Browning Li Cronin Ebenezer David Tonya Hayden Han Li Travis Lim Panagiotis Maniatis Palak Patel Mathew Pauly Amanda Poe Lili Punkova Vera Semenova Evelene P. Steward-Clark Alexandra Tejada Briana Zellner 《MMWR. Morbidity and mortality weekly report》2021,70(9):312
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Wang WS; Hsieh RK; Chiou TJ; Liu JH; Fan FS; Yen CC; Tung SL; Chen PM 《Japanese journal of clinical oncology》1998,28(9):551-554
A 54-year-old man was treated with weekly 24-h infusion of high-dose
5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon
cancer. At first, he tolerated the treatment well and no significant
toxicity was identified. After a total of eight courses of treatment, a
stable disease was observed, but mild shortness of breath was found on
occasion. The patient had no previous history of cardiac disease and the
heart performance assessed by left ventricular ejection fraction before
treatment was normal. Unfortunately, acute pulmonary edema with lethal
cardiogenic shock occurred during the ninth course of treatment, in spite
of intensive medical treatment. The chest X-ray showed extreme
cardiomegaly. Repeated assessment of his heart function by echocardiogram
and ventricular ejection fraction revealed a very poor cardiac performance.
Toxic cardiogenic shock during weekly 24-h infusion of high-dose
5-fluorouracil and leucovorin is extremely rare. To the best of our
knowledge, no case has been reported in the English literature. We report a
case and the relevant literature about the incidence, clinical picture and
possible pathophysiology on 5-fluorouracil-related cardioxicity is
reviewed.
相似文献
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R H Israel J M Kohan R H Poe M C Kallay D W Greenblatt S Rathbun 《Respiration; international review of thoracic diseases》1988,53(4):225-231
Eucapneic hyperventilation of cold air (EHCA) provokes bronchospasm in asthmatics. Although inhaled cromolyn powder and sympathomimetic solutions have attenuated the bronchospasm induced by EHCA, comparison of both drugs in solution has not been performed. We performed a prospective double-blind study comparing cromolyn solution, metaproterenol solution, and placebo (normal saline) given prior to EHCA. Eight asthmatics defined by a 20% reduction in forced expiratory volume in 1s (FEV1) after EHCA consented to the study. Patients were tested on 3 separate occasions at a similar time of day. Each session began with a determination of FEV1 followed by a randomized double-blind treatment. A repeat FEV1 (pre-EHCA) was performed 20 min after drug inhalation. Twelve minutes of EHCA was performed consisting of 4 min of tidal breathing, 4 min of eucapneic hyperventilation (60-70% of the predicted MVV) and a final 4 min of tidal breathing. FEV1 was performed immediately, 5 min, and 10 min after EHCA. The lowest value was defined as the post-EHCA FEV1. The pre-EHCA FEV1 was significantly larger after metaproterenol pretreatment compared to the pre-EHCA FEV1 following cromolyn (p = 0.01) and saline (p = 0.04). Metaproterenol pretreatment had a significant protective effect in comparison to placebo pretreatment (p less than 0.01). No other paired comparisons (cromolyn vs. placebo, cromolyn vs. metaproterenol) achieved statistical significance at a 0.05 level. In conclusion, metaproterenol is superior to cromolyn in protecting against cold-air-induced bronchospasm. 相似文献