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991.
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993.
Idiopathic arterial calcification in infancy is usually fatal with death in early life and diagnosis at post mortem. This report describes a unique, late presentation with hypertension and cardiac failure in a child aged 33 months, found to have widespread arterial calcification at radiological imaging. The calcium-phosphate axis was normal and there was no other demonstrable cause for calcification. Additionally, the histological features of arterial calcification at renal biopsy paralleled the findings in infants with this disorder. The late presentation in this case is unusual and has not been previously reported. Ultrasound and CT are sensitive for calcification, and the disease should be suspected in children presenting with cardiac or respiratory manifestations and features of arterial calcification, where no metabolic cause is established. 相似文献
994.
Burke WM Williams JA Fenner DE Hammoud MM 《American journal of obstetrics and gynecology》2004,191(5):1772-1776
OBJECTIVE: The study was undertaken to identify factors contributing to the poor student perception of the obstetrics and gynecology clerkship. STUDY DESIGN: Third-year medical students at the University of Michigan complete an annual questionnaire about the overall quality of their clinical experiences. In addition, at the end of each rotation, the students complete an evaluation form assessing various aspects of their learning experience. We reviewed data collected from 2000 to 2002. We calculated effect sizes using mean scores and SDs to compare individual aspects of the learning environment across the clerkships. RESULTS: Twenty-six percent of the third-year medical students at the University of Michigan rated the strength of their obstetrics and gynecology experience as very or exceptionally strong. Compared with the other 6 clerkships, the rotation had one of the lowest ratings for overall quality. Aspects of the clerkship experience we identified as potentially explaining this overall poor rating include the clarity of the clerkship goals and objectives, clarity of expectations for student performance, accessibility of faculty, experiences in learning history-taking skills, experiences in learning physical examination skills, and student perception that they were treated in a respectful/professional manner. CONCLUSION: Aspects of the clerkship experience identified by this study as potentially explaining the low ratings of the obstetrics and gynecology rotation should be studied in greater detail. Addressing these factors will be critical for improving the overall student perception of the obstetrics and gynecology clerkship. 相似文献
995.
Advanced Colorectal Carcinomas Measuring 20 mm or Less Exhibit Markedly Higher Invasiveness Despite Their Size 总被引:1,自引:0,他引:1
Kunii Y Kamano T Tomiki Y Hirai S Kasamaki S Sakamoto K 《Digestive diseases and sciences》2004,49(11-12):1899-1905
To analyze the biology of small (20 mm or less) advanced colorectal carcinomas (SAC), 24 cases, 22 small early colorectal carcinomas (SEC) of similar size, and 52 advanced colorectal carcinomas (AC) were studied. The proliferative (Ki-67) labeling index for SAC was 65.9+/-17.1%, significantly higher than those for SEC (30.9+/-13.7%) or AC (43.0+/-17.1%) (P < 0.01). Matrix metalloproteinase (MMP)-9 and tissue inhibitors of metalloproteinase (TIMP)-2 expressions for SAC were 62.5 and 79.2%, respectively, significantly higher than those for SEC (4.5, 13.6%) or AC (21, 33%) (P < 0.01). Small advanced carcinomas have higher invasiveness than SEC or AC and may represent a different type of cancer. 相似文献
996.
Okamoto M Dan H Sakamoto K Takeo K Shimizu K Kohno S Oda I Isobe S Suzuki T Kohyama K Dan I 《NeuroImage》2004,21(1):99-111
The recent advent of multichannel near-infrared spectroscopy (NIRS) has expanded its technical potential for human brain mapping. However, NIRS measurement has a technical drawback in that it measures cortical activities from the head surface without anatomical information of the object to be measured. This problem is also found in transcranial magnetic stimulation (TMS) that transcranially activates or inactivates the cortical surface. To overcome this drawback, we examined cranio-cerebral correlation using magnetic resonance imaging (MRI) via the guidance of the international 10-20 system for electrode placement, which had originally been developed for electroencephalography. We projected the 10-20 standard cranial positions over the cerebral cortical surface. After examining the cranio-cerebral correspondence for 17 healthy adults, we normalized the 10-20 cortical projection points of the subjects to the standard Montreal Neurological Institute (MNI) and Talairach stereotactic coordinates and obtained their probabilistic distributions. We also expressed the anatomical structures for the 10-20 cortical projection points probabilistically. Next, we examined the distance between the cortical surface and the head surface along the scalp and created a cortical surface depth map. We found that the locations of 10-20 cortical projection points in the standard MNI or Talairach space could be estimated with an average standard deviation of 8 mm. This study provided an initial step toward establishing a three-dimensional probabilistic anatomical platform that enables intra- and intermodal comparisons of NIRS and TMS brain imaging data. 相似文献
997.
998.
Sakamoto K Ohmori T Takei H Hasuo K Rino Y Takanashi Y 《The Annals of thoracic surgery》2004,78(2):705-707
Spontaneous hemopneumothorax (SHP) is a rare clinical entity, and an emergent operation due to continuous bleeding or hypovolemic shock is at times necessary. Although allogeneic blood transfusions are urgently required for significant blood loss, autologous blood transfusions can also be considered in patients with SHP. We herein report two cases of successful autologous blood transfusions using blood in the pleural space, decreasing or obviating the need for allogeneic blood transfusion. 相似文献
999.
Nakatani Y Miyagi Y Takemura T Oka T Yokoi T Takagi M Yokoyama S Kashima K Hara K Yamada T Nozawa A Inayama Y Sakamoto K Ogawa N Kitamura H Resl M Cho SH Koss MN Mark EJ 《The American journal of surgical pathology》2004,28(7):921-927
It is now known that gene mutation of beta-catenin with subsequent nuclear/cytoplasmic (N/C) overaccumulation of the protein plays an important role in tumorigenesis of various organs. We recently demonstrated that low-grade adenocarcinoma of the fetal lung type (L-FLAC)/well-differentiated fetal adenocarcinoma (WDFA), the epithelial prototype of classic pulmonary blastoma (CPB), shows N/C localization of beta-catenin with genetic mutation. This prompted us to further investigate the state of beta-catenin abnormality in CPB and related neoplasms. We studied 9 lung tumors previously diagnosed as biphasic pulmonary blastoma (PB). Histologically, 4 cases (median age 34 years) were CPB with l-FLAC/WDFA as the epithelial component, whereas 5 cases (median age 65 years) were a variant of carcinosarcoma with high-grade FLAC/clear cell adenocarcinoma with fetal lung features as the epithelial component, which we term the blastomatoid variant of carcinosarcoma (BCS). Immunohistochemically, all 4 CPBs showed aberrant N/C localization of beta-catenin both in the epithelial and mesenchymal components, with especially high staining intensity in the budding glands and morules. In contrast, all 5 BCSs showed preserved or diminished membranous expression and no significant N/C expression of beta-catenin in the epithelial component, and absent or focal N/C expression of beta-catenin in the mesenchymal component. Mutational analysis of exon 3 of the beta-catenin gene revealed that 3 CPBs harbored missense mutations (S29F, S37F, and S37F), whereas none of the 5 BCSs had this mutation. This study suggests that beta-catenin gene mutations may play a role in the tumorigenesis of CPB. Although CPB and BCS have often been grouped together as biphasic PB, they are different entities based on immunohistochemical and molecular analysis of beta-catenin. Immunostaining for beta-catenin is useful for the discrimination. 相似文献
1000.
Between January 1997 and July 2003, 156 acute nasal fractures were treated by closed reduction in Ishikiri-Seiki Hospital. For all patients, x-ray and computed tomography (CT) taken pre- and postoperatively were used to classify fractures and evaluate postoperative conditions. Acute nasal fractures requiring surgery were classified into the following 5 types. Unilateral type (U), bilateral type (B), frontal type (F), laterofrontal type (L), and comminuted type (C). Postoperative conditions were classified as good, fair, or poor. On statistical analysis, it was found that reduction is easier in the U, F, B, L, and C types in order. Furthermore, it was found that in the U, B, and F types, reduction can be performed after swelling has subsided, but in the L and L+C types, reduction should be performed earlier. On follow-up x-ray and CT, there was no significant difference between the postoperative evaluation and follow-up evaluation. A few overreduced cases improved, but correct reduction was preferable to overreduction. Accurate preoperative understanding of the fracture type and postoperative evaluation by x-ray and CT are necessary to obtain good results and to decrease secondary deformity caused by poor primary reduction. 相似文献