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21.
Patel  B; Markivee  CR; Mahanta  B; Vas  W; George  E; Garvin  P 《Radiology》1988,167(3):685-687
Twenty-one patients with insulin-dependent diabetes mellitus received simultaneous renal and segmental pancreatic transplants. A retrospective analysis of 112 real-time ultrasound (US) images, 108 technetium-99m glucoheptonate scinti-scans, 55 computed tomography (CT) scans, and 11 cystograms was performed. Complications that were observed included pancreatic transplant rejection, pancreatitis, arteriovenous occlusions, hemorrhage, abscesses, and extravasation at the pancreaticocystostomy site. Scintigraphy is a sensitive indicator of normal transplant function but is non-specific when findings are abnormal. Real-time US aids in the differentiation of acute rejection from pancreatitis and arteriovenous occlusion. CT is helpful for evaluation of postoperative complications. Imaging may play an important role in the noninvasive management of pancreatic transplants.  相似文献   
22.
Strangulation in child abuse: CT diagnosis   总被引:2,自引:0,他引:2  
Bird  CR; McMahan  JR; Gilles  FH; Senac  MO; Apthorp  JS 《Radiology》1987,163(2):373-375
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients.  相似文献   
23.
Focal liver masses: differential diagnosis with pulsed Doppler US   总被引:8,自引:0,他引:8  
Duplex Doppler ultrasound (US) was used in 68 consecutive patients with focal liver lesions, including 12 hepatocellular carcinomas, one cholangiocarcinoma, 37 metastases, 15 hemangiomas, one hemangioendothelioma, and two focal nodular hyperplasias. Of the hepatocellular carcinomas, six were diffusely hyperechoic, two were hypoechoic, two were single hyperechoic lesions, and two were multifocal and hyperechoic. All ten tumors with Doppler shifts of 5 kHz or above proved to be hepatocellular carcinomas. The other two hepatocellular carcinomas showed Doppler shifts of 3 kHz. In contrast, no hemangioma showed shifts above 0.7 kHz, and ten of the 15 gave no detectable signal. Of the metastases, 20 gave no signal and 17 had signals of up to 4 kHz. Three-kilohertz signals were also obtained from a cholangiocarcinoma, a hemangioendothelioma, and focal nodular hyperplasia. Correlation with angiographic findings suggested that the high-velocity Doppler signals were associated with large pressure gradients due to arteriovenous shunting. Duplex Doppler US can therefore aid in the differential diagnosis of diffuse and focal liver lesions.  相似文献   
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Pulmonary histiocytosis X: comparison of radiographic and CT findings   总被引:6,自引:0,他引:6  
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities.  相似文献   
26.
SUMMARY: Transforming growth factor-β (TGF-β) has been considered the principal cytokine involved in the pathogenesis of renal fibrosis. In the present study, we evaluated TGF-β activity in occasional samples from 22 normal individuals and 29 patients (11 with focal glomerulosclerosis, 11 with membranous nephropathy, five with Berger disease, one with type I membranoproliferative glomerulonephritis and one with postinfectious glomerulonephritis) using a CCL-64 mink lung cell growth inhibition assay.
A significantly increased urinary TGF-β activity (reported in relation to urine creatinine, Ucreat, and median) was observed in patients with glomerulonephritis compared with normal individuals ( P <0.01). the patients with Berger disease [median (Md) = 9.96/10 μg Ucreat.], membranous glomerulonephritis (Md = 7.23/10 μg Ucreat.) and focal glomerulosclerosis (Md = 16.6/10 μg Ucreat.) showed higher urinary TGF-β than normal individuals (Md = 1.09/10 μg Ucreat.) ( P <0.01). We found a positive correlation between the TGF-β activity in the urine of these patients and the incidence of segmental glomerulosclerosis ( r = 0.45, P <0.05) and their plasma creatinine levels ( r = 0.87, P <0.01). A negative correlation was observed between the TGF-β activity in the urine of these patients and their creatinine clearance ( r =−0.75, P <0.01).
Our data suggest that measurement of urinary TGF-β activity could be a useful non-invasive procedure for the evaluation of renal TGF-β production, permitting the assessment of prognosis and the evaluation of therapeutic efficacy in patients with renal disease.  相似文献   
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28.
Digital imaging of the chest   总被引:4,自引:0,他引:4  
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.  相似文献   
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30.
Amyloid involvement of the breast is infrequently reported and may have clinical and radiological features suspicious for a primary breast malignancy. We describe a case of amyloid of the breast in which asymptomatic mammographic findings were suspicious for locally recurrent disease in a patient with previously treated breast cancer.  相似文献   
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