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71.
Chronic obstructive pulmonary disease (COPD) is characterized by variable contributions of emphysema and airway disease on computed tomography (CT), and still little is known on their temporal evolution. We hypothesized that quantitative CT (QCT) is able to detect short-time changes in a cohort of patients with very severe COPD. Two paired in- and expiratory CT each from 70 patients with avg. GOLD stage of 3.6 (mean age = 66 ± 7.5, mean FEV1/FVC = 35.28 ± 7.75) were taken 3 months apart and analyzed by fully automatic software computing emphysema (emphysema index (EI), mean lung density (MLD)), air-trapping (ratio expiration to inspiration of mean lung attenuation (E/I MLA), relative volume change between − 856 HU and − 950 HU (RVC856–950)), and parametric response mapping (PRM) parameters for each lobe separately and the whole lung. Airway metrics measured were wall thickness (WT) and lumen area (LA) for each airway generation and the whole lung. The average of the emphysema parameters (EI, MLD) increased significantly by 1.5% (p < 0.001) for the whole lung, whereas air-trapping parameters (E/I MLA, RVC856–950) were stable. PRMEmph increased from 34.3 to 35.7% (p < 0.001), whereas PRMNormal decrased from 23.6% to 22.8% (p = 0.012). WT decreased significantly from 1.17 ± 0.18 to 1.14 ± 0.19 mm (p = 0.036) and LA increased significantly from 25.08 ± 4.49 to 25.84 ± 4.87 mm2 (p = 0.041) for the whole lung. The generation-based analysis showed heterogeneous results. QCT detects short-time progression of emphysema in severe COPD. The changes were partly different among lung lobes and airway generations, indicating that QCT is useful to address the heterogeneity of COPD progression. • QCT detects short-time progression of emphysema in severe COPD in a 3-month period. • QCT is able to quantify even slight parenchymal changes, which were not detected by spirometry. • QCT is able to address the heterogeneity of COPD, revealing inconsistent changes individual lung lobes and airway generations.  相似文献   
72.
While adequately treated acute Monteggia lesions have a good prognosis, results in neglected Monteggia fractures are varied. Outcomes improved as a consequence of a better understanding of the pathology of the elbow joint. Persistent malposition of the radial head leads to maldevelopment of the radioulnar and radiohumeral joints. The following parameters have a crucial influence on prognosis of neglected Monteggia fractures: morphological changes of the elbow joint, duration of dislocation and the age of the patient. An individual treatment concept is necessary for an adequate correction of the complex malformations. Concerning the indications for corrective surgical procedures it is important to estimate whether they are advantageous. Not every dislocation of the radial head has to be treated and sometimes the spontaneous development can be functionally and symptomatically better than an unsuccessful attempt at correction. This publication presents the criteria which are necessary for a correct treatment of neglected Monteggia lesions. The key procedure of correction is osteotomy of the ulna which can range from simple angulation up to complex multidimensional corrections. The results of treatment of neglected Monteggia lesions depend strongly on the surgeon’s experience and the technique chosen.  相似文献   
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74.
The authors investigated the significance of vomiting for hyperamylasemia and sialadenosis in patients with bulimia nervosa. Hyperamylasemia was found in 61% of the bulimics and in 20% of the restrictor anorectics but in no patients with binge-eating syndrome. In more than three fourths of the bulimics there was a close positive correlation between the frequency of vomiting and total serum amylase levels. Both frequency and type of vomiting seem to be relevant to the extent of salivary gland enlargement. The significance of vomiting for the etiopathology of hyperamylasemia and for the diagnosis of eating disorders will be discussed. © 1993 by John Wiley & Sons, Inc.  相似文献   
75.
Journal of Neuro-Oncology - MYC-driven medulloblastomas are highly aggressive childhood tumors with dismal outcomes and a lack of new treatment paradigms. We identified that targeting replication...  相似文献   
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77.
The AdaptResponse trial is designed to test the hypothesis that preferential adaptive left ventricular‐only pacing with the AdaptivCRT® algorithm reduces the incidence of the combined endpoint of all‐cause mortality and intervention for heart failure (HF) decompensation, compared with conventional cardiac resynchronization therapy (CRT), among patients with a CRT indication, left bundle branch block (LBBB) and normal atrioventricular (AV) conduction. The AdaptResponse study is a prospective, randomized, controlled, single‐blinded, multicentre, clinical trial ( ClinicalTrials.gov Identifier: NCT02205359), conducted at up to 200 centres worldwide. Following enrolment and baseline assessment, eligible subjects will be implanted with a CRT system containing the AdaptivCRT algorithm, and randomized in a 1:1 fashion to either a treatment (‘AdaptivCRT’) or control (‘Conventional CRT’) group. The study is designed to observe a primary endpoint in 1100 patients (‘event‐driven’) and approximately 3000 patients will be randomized. The primary endpoint is the composite of all‐cause mortality and intervention for HF decompensation; secondary endpoints include all‐cause mortality, intervention for HF decompensation, clinical composite score (CCS) at 6 months, atrial fibrillation, quality of life measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), health outcome measured by the EQ‐5D instrument, all‐cause readmission after a HF admission, and cost‐effectiveness. The AdaptResponse clinical trial is powered to assess clinical endpoints and is expected to provide definitive evidence on the incremental utility of AdaptivCRT‐enhanced CRT systems.  相似文献   
78.

Background

In view of the conflicting guidelines issued by national and international scientific societies, debate about the indications for prophylactic extraction of wisdeom teeth is ongoing. This prospective study was therefore set up to explore the complications associated with wisdom teeth and requiring in-patient treatment.

Patients and Methods

From January /2003 to December 2003, 21 subjects were admitted for treatment of complications associated with wisdom teeth. The medical history was recorded for each of these patients, as were the cause and type of the complications. The parameter used to quantify the severity of any infections was the CRP, and the overall clinical complexity level of each case was assessed by the length of stay in hospital (and the duration of intensive care if this had been necessary). The characteristics of patients in the group with postoperative complications were compared to those of patients with complications attributable to pericoronitis. Moreover, complications in patients who had undergone prophylactic extraction of wisdom teeth that had not been causing any symptoms were compared with those in patients whose wisdom teeth had been extracted because of morbidity.

Results

Overall, 18 deep-space infections (15 abscesses, 2 inflammatory infiltrations, 1 case of phlegmonous cellulitis), 2 mandibular fractures and 1 lingual nerve injury were noted within 1 year. The complications resulted from surgical procedures in 15 of the 21 cases, while in 6 they had their origin in pericoronitis. Extensive surgery or intensive care was required only for patients with postoperative complications. The length of stay in hospital was significantly greater for patients with postoperative complications (p= 0.007, U-test). However, 9 of these 15 patients reported preoperative episodes of infection. Thus, more than two thirds of the complications could be traced back to wisdom teeth that were causing symptoms.

Conclusion

In our clinic’s catchment area, infectious complications were more frequent and more severe and required more intensive and longer treatment in hospital than complications arising from pericoronitis. However, complications of prophylactic extraction of wisdom teeth were decidedly less frequent than direct or indirect complications of extraction of symptomatic teeth. Thus, our data tend to support the concept of elective extraction of wisdom teeth with the aim of preventing serious infections.  相似文献   
79.
The concept that macrophages can become foam cells as a result of a disturbed balance between the uptake of cholesterol from lipoproteins and cholesterol efflux is generally accepted. ABCA1 and ABCG1 are two cholesterol transporters that may act sequentially to remove cellular cholesterol, but currently their combined role in vivo is unknown. We report here that targeted disruption of both ABCA1 and ABCG1 in mice, despite severe plasma hypocholesterolemia, leads to massive lipid accumulation and foam cell formation of tissue macrophages. A complete ablation of cellular cholesterol efflux in vitro is observed, whereas in vivo macrophage-specific reverse cholesterol transport to the feces is markedly decreased. Despite the massive foam cell formation of tissue macrophages, no lipid accumulation was observed in the vascular wall, even in mice of 1 year old, indicating that the double knockout mice, possibly because of their hypocholesterolemia, lack the trigger to attract macrophages to the vessel wall. In conclusion, even under hypocholesterolemic conditions macrophages can be converted into foam cells, and ABCA1 and ABCG1 play an essential role in the prevention of foam cell formation.  相似文献   
80.
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