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81.
The aim of the present study was to determine whether human endometrial cells are able to secrete beta-chorionic gonadotrophin (betaCG). Immunohistochemical studies and in-situ hybridization were performed in order to provide evidence for the occurrence of betaCG in the normal endometrium in 15 patients in the proliferative phase, two patients in the periovulatory phase and 13 patients in the secretory phase. Neither immunohistochemical nor hybridization reactions could be recognized during the proliferative phase. In contrast, both protein and betaCG mRNA were observed in the glandular cells of the endometrium during the secretory phase. The results were supported by Western blotting of secretory phase endometrium extracts and the assessment of the functional secretory capacity of primary endometrium cultures. In comparison with cultured and separated cell fractions, tissue extracts showed a higher betaCG, indicating a regulatory interaction. In conclusion, betaCG can be demonstrated in normal human cyclic endometrium, suggesting a paracrine role in endometrial physiology.   相似文献   
82.
Lansteiner Award. Some aspects of serological specificity   总被引:1,自引:0,他引:1  
GW Bird 《Transfusion》1990,30(5):390-400
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83.
Rectal biopsy as a cause of rectal ulceration   总被引:1,自引:0,他引:1  
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84.
Segond tibial condyle fracture: lateral capsular ligament avulsion   总被引:8,自引:0,他引:8  
Dietz  GW; Wilcox  DM; Montgomery  JB 《Radiology》1986,159(2):467-469
Avulsion fractures in the appendicular skeleton are a result of stress on a specific structure that is firmly attached to bone. A small avulsion fracture from the directly lateral surface of the lateral tibial condyle results from excessive tension on the lateral capsular ligament of the knee joint. Recognition of this fracture on an anteroposterior radiograph of a traumatized knee represents substantial evidence of major injury to the lateral joint capsule. This fracture also has a strong association with rupture of the anterior cruciate ligament. The avulsed tibial fragment is remarkably constant in site and appearance. The typical fragment is isolated by a longitudinal fracture line separating a small piece of bone from the lateral tibia. It is elliptical in outline (10 X 3 mm), with its proximal border lying 4 mm distal to the subarticular cortex of the lateral tibial condyle. A hemarthrosis of the knee joint is consistently visible.  相似文献   
85.
Academic uroradiology: the future   总被引:1,自引:1,他引:0  
Hartman  GW; McClennan  BL; Pfister  RC 《Radiology》1986,158(2):559-561
Radiologic education, research, and the practice of radiology will be of the highest quality in the future if academic departments stress organ-system subspecialization while continuing to integrate and interface with technique-based specialists. Planning should begin now to effect an orderly progression to an organ-system-based subspecialty structure for radiology training in general and for uroradiology specifically. Uroradiologists should remain as central consultants to their clinical counterparts, working collaboratively with urologists in clinical endeavors of mutual relevance. More fellowships in uroradiology should be offered that attempt to incorporate all imaging methods and procedures into the curriculum. These issues are addressed in the context of patient care, service, education, and cost containment.  相似文献   
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Cortical variability and asymmetry in normal aging and Alzheimer's disease   总被引:5,自引:3,他引:2  
The onset of Alzheimer's disease (AD) is accompanied by a complex and distributed pattern of neuroanatomic change, difficult to distinguish clinically from dynamic alterations in normal aging. Extreme variations in the sulcal patterns of the human cortex have made it difficult to identify diffuse and focal variations in cortical structure in neurodegenerative disease. We report the first comprehensive 3D statistical analysis of deep sulcal structure in vivo, in both normal aging and dementia. High-resolution 3D T1-weighted fast SPGR (spoiled GRASS) MRI volumes were acquired from 10 patients diagnosed with AD (NINCDS-ARDRA criteria; age: 71.9 +/- 10.7 years) and 10 normal subjects matched for age (72.9 +/- 5.6 years), gender, educational level and handedness. Scans were digitally transformed into Talairach stereotaxic space. To determine specific patterns of cortical variation in dementia patients, 3D average and probabilistic maps of primary deep sulci were developed for both normal and AD groups. Major sulci (including supracallosal, cingulate, marginal, parieto-occipital, anterior and posterior calcarine sulci, and Sylvian fissures) were modeled as complex systems of 3D surfaces using a multi-resolution parametric mesh approach. Variations and asymmetries in their extents, curvature, area and surface complexity were evaluated. Three- dimensional maps of anatomic variability, structural asymmetry and local atrophy indicated severe regionally selective fiber loss in AD. A midsagittal area loss of 24.5% at the corpus callosum's posterior midbody (P < 0.025) matched increases in structural variability in corresponding temporo-parietal projection areas. Confidence limits on 3D cortical variation, visualized in 3D, exhibited severe increases in AD from 2 to 4 mm at the callosum to a peak SD of 19.6 mm at the posterior left Sylvian fissure. Normal Sylvian fissure asymmetries (right higher than left; P < 0.0005), mapped for the first time in three dimensions, were accentuated in AD (P < 0.0002), and were greater in AD than in controls (P < 0.05). Severe AD-related increases in 3D variability and asymmetry may reflect disease-related disruption of the commissural system connecting bilateral temporal and parietal cortical zones, regions known to be at risk of early metabolic dysfunction, perfusion deficits and selective neuronal loss in AD.   相似文献   
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