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101.
Although genitourinary tract disorders are common in acquired immunodeficiency syndrome (AIDS), little attention has been paid to their manifestations on computed tomographic (CT) scans. The authors reviewed the CT scans of 86 patients infected with the human immunodeficiency virus for CT manifestations of primary or secondary involvement of the genitourinary tract. Genitourinary tract abnormalities identified in the 86 patients included nephromegaly in 34 (40%), hilar adenopathy in 30 (35%), bladder wall thickening in 19 (22%), medullary hyperattenuation in 12 (14%), renal calcifications in seven (8%), adnexal masses in five (6%), hydronephrosis in four (5%), pyelonephritis in three (3%), renal abscesses in three (3%), and solid renal masses in three (3%). Although these abnormalities are seen on CT scans in many other diseases, in the AIDS patient they often indicate the presence of an AIDS-related renal disease or involvement of the genitourinary tract by an AIDS-related neoplasm or infection.  相似文献   
102.
Current uses of CT and MR imaging in the staging of lung cancer   总被引:8,自引:0,他引:8  
In 1986, Pearson reported on the lung cancer experience in Toronto over the past 25 years. The number of unresectable operations had decreased from 25 to 5%. Operative mortality was down from 10 to 3% and 5-year survival increased from 23 to 40%. The reason for these statistics, he stated, was not better surgery but better selection of surgical candidates, due to invasive and noninvasive techniques. CT and MR imaging are part of those noninvasive techniques and also play an important role in guiding the invasive techniques. Although controversy exists regarding the proper size criteria and axis length in nodal assessment, and the use of imaging in staging T1N0M0 lung cancer, most clinicians rely on CT scans to evaluate the patient with lung cancer. No other imaging test is as comprehensive in evaluating the patient with lung cancer. The main role of MR imaging at this time is as a problem-solving tool. Focused MR imaging examinations should be used to evaluate or to resolve specific questions related to invasion of the chest wall, vascular structures, or brachial plexus, and adrenal mass characterization. MR imaging is also useful in evaluating the hilum and mediastinum in patients who cannot receive intravenous contrast for CT evaluation. The overall accuracy of CT and MR imaging is disappointing, particularly in crucial areas of determining operability such as distinguishing between patients with Stage IIIA or IIIB disease. It is unlikely that CT diagnosis can significantly improve; however, there is substantial potential for improved diagnostic accuracy with MR imaging as continued research moves this technology forward. The future may bring improved tissue characterization and vascular evaluation. At present, CT remains the procedure of choice in the initial assessment of the patient with lung cancer. The radiologist must be prepared to interpret these imaging studies in light of the specific findings that determine the stage and thus potential resectability of lung cancer.  相似文献   
103.
104.
Clinical, haematological and biochemical features in 42 subjects with S-beta thalassaemia (31 subjects with S-beta° thalassaemia and 11 subjects with S-beta+ thalassaemia); and in 42 with homozygous sickle cell disease were compared. Persistent splenomegaly was more common and painful crises less common in the S-beta thalassaemia group. Total Hb was higher and reticulocyte count lower in S-beta+ thalassaemia than in S-beta° thalassaemia or SS disease. Microcytosis was marked in the S-beta thalassaemia group while the MCV was normal in sickle cell anaemia. Hb F was significantly higher in the S-beta° thalassaemia group, without any influence on the severity of the disease. Many features suggest that sickle cell thalassaemia is more severe in Algeria than in Negro subjects and similar to the disease in Italian patients.  相似文献   
105.
The Klippel-Trenaunay-Weber syndrome consists of cutaneous port wine hemangiomas, superficial venous varicosities, and soft tissue and bony hypertrophy of an extremity. We describe three patients with this syndrome with hypodense lesions in the spleen which in one case became isodense after bolus contrast CT. In one case ultrasound found numerous echopenic and echogenic masses. These lesions are presumed to represent multiple hemangiomata.  相似文献   
106.
Magnetic resonance imaging with tissue tagging is a noninvasive technique for measuring three-dimensional motion and deformation in the human heart. Tags are regions of tissue whose longitudinal magnetization has been altered before imaging so that they appear dark in subsequent magnetic resonance images. They then move with the underlying tissue and serve as easily identifiable landmarks within the heart for the detailed detection of motion. Many different motion and strain parameters can be determined from tagged magnetic resonance imaging. Strain components that are based on a high density of tag data, such as circumferential and longitudinal shortening, or parameters that are combinations of multiple strain components, have highest measurement precision and tightest normal ranges. The pattern of three-dimensional motion and strain in the heart is important clinically, because it reflects the basic mechanical function of the myocardium at both local and global levels. Localized abnormalities can be detected and quantified if the pattern of deformation in a given heart is compared to the normal range for that region, because normal motion and strain in the left ventricle is spatially heterogeneous. Contraction strains typically are greatest in the anterior and lateral walls and increase toward the apex. The direction of greatest contraction lies along a counter clockwise helix from base to apex (viewed from the base) and approximates the epicardial muscle fiber direction. This fiber geometry also results in long-axis torsion during systole. Ejection is accomplished primarily by radially inward motion of the endocardium and by descent of the base toward the apex during systole.  相似文献   
107.
Because of greatly enhanced contrast resolution and the advantages of cross-sectional visualization of lung anatomy, computed tomography (CT) has the potential to add significantly to the conceptualization of parenchymal lung disease. Although the value of CT has been well documented in the detection and characterization of lung nodules, the role of CT has been less clearly defined for other types of lung disease. This report describes the CT appearance of distal air-space disease. As demonstrated by the use of inflated and contrast-injected lungs obtained at autopsy, air-space disease is definable by the following: poorly marginated nodules ranging up to 1 cm in size; coalescence of nodules; air-bronchograms and air-alveolograms; ground-glass opacification; and distinct zonal patterns of distribution, including central and peripheral configurations. These patterns of air-space abnormalities are further refined by review of case material, including examples of air-space disease secondary to aspiration and primary intraalveolar disease, evaluated by the authors over a five-year period.  相似文献   
108.
CT of the solitary pulmonary nodule   总被引:3,自引:0,他引:3  
Computed tomography (CT) with thin sections (2-5 mm) was used to assess tissue density in 91 apparently noncalcified pulmonary nodules in 88 patients. The study included 45 primary lung malignancies and 13 metastases proven by subsequent lung biopsy or thoracotomy. There were 33 benign lesions of which 13 were biopsy proven. The other 20 nodules were presumed benign on the basis of serial radiography showing no growth. A representative CT number based on the 32 most dense voxels was calculated for each lesion. For the primary malignancies, the mean representative CT number was 92 H, with a standard deviation of 18 H. The highest representative CT number for any malignant lesion was 147 H. Of the 33 benign lesions, 20 had a representative CT number of 164 H or greater. It is presumed that nodules with representative CT numbers of 164 H are benign, and that diffuse calcification likely accounts for the higher CT number of some benign lesions. CT has proven to be more objective and more sensitive than standard tomography in assessing the density of pulmonary nodules.  相似文献   
109.
From January 2000, the Council of State has harmonised the jurisprudence with the Court of Appeal, changing the responsibility of medical practitioners by requiring them to provide proof that information was both given and understood by their patients. This obligation to inform patients raises several questions: who should give the information? to whom should the information be addressed? how can proof of this information be provided? what should the information be? The authors sent a questionnaire to practicing cardiologists by the internet site of the French Society of Cardiology from the 1st December 2002 to 15th January 2003. Three hundred and thirty-two replies were received of which 305 could be exploited. The activities of the cardiologists who replied were mainly in public hospitals (51.8%), private (18.2%) or mixed (30%). Patient information was mainly performed before invasive procedures, especially coronary angiography (90%) or cardiac pacing (77.3%). On the other hand, it was less commonly undertaken before exercise stress tests (63.2%) or transoesophageal echocardiography (61.4%), although these percentages are much higher than those recorded during previous enquiries in 2000 and 2001. The information given was, in the large majority of cases, that proposed by the French Society of Cardiology and it was usually the practitioner who ordered the investigation who informed the patient (45.4%). In 2002, the role of the nurse was much greater as the nurse informed the patient in 27.2% of cases. The patient was generally given the information the day before the procedure was carried out (74.1%) with complementary information (90.7%), and less than 1% of patients declined the investigation under these conditions. In order to provide proof of patient information, the practitioner usually required the patient's signature (58.3% of cases); less commonly, the referring physician was informed by letter (13.9% of cases) or a note was made in the patient's file (33.9% of cases). The new requirements for patient information have changed medical practice in nearly 53.5% of cases. Finally, although patient information is considered to be part of the normal patient-doctor relationship in most cases (42.7%), doctors thought that patients interpreted this procedure as a cover for the medical team in 18.2% of cases. The information bases most commonly used to determine the methods of informing patients and the nature of the information to be provided were medical reviews (38.9%) or the internet (30.5%). The authors conclude that patient information is carried out before complementary cardiological investigations. The new laws of the Code of Public Health are not well known. Finally, the proof of patient information is not easily provided and the majority of cardiologists request written patient consent, which is not a legal requirement.  相似文献   
110.
We report a case of congenital cystic adenomatoid lung malformation, type I in the Stocker classification, diagnosed at ultrasonography at 27 weeks gestation. The lesion stabilized as was the hydramnios. Vaginal delivery was uneventful. Early surgery with lobectomy led to a favorable outcome at 8 months follow-up. Congenital adenomatoid lung malformation is a rare finding. Prenatal ultrasound diagnosis has enabled early treatment and improved prognosis.  相似文献   
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