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排序方式: 共有7574条查询结果,搜索用时 15 毫秒
11.
Michael Brauckhoff Oliver Gimm Udo Bilkenroth Raoul Hinze Henning Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2002,387(5-6):201-203
BACKGROUND: In most examined populations the RET germline polymorphism S836S is found in about 3.6% of the normal population but in about 9% of patients suffering from sporadic C-cell hyperplasia or medullary thyroid carcinoma. The polymorphism S836S is thought to be involved in the development of sporadic medullary thyroid carcinoma. CASE PRESENTATION: We report a 48-year-old woman suffering from primary hyperparathyroidism (parathormone 121-166 pg/ml, normal <72), bilateral diffuse and nodular C-cell hyperplasia (calcitonin after pentagastrin administration 156 pg/ml, normal <4.6), and papillary thyroid carcinoma. Two commercial analyses of RET did not reveal any germline mutation within the known hot spots. However, sequencing revealed the presence of the RET polymorphism S836S. Following total thyroidectomy and removal of two hyperplastic parathyroid glands parathormone decreased to 51 pg/ml and calcitonin was no longer detected. CONCLUSIONS: The pathogenetic importance of the RET polymorphism S836S is still obscure. However, according to the published overrepresentation of the RET polymorphism S836S in patients suffering from apparent sporadic medullary thyroid carcinoma, it is conceivable that it also plays a role in multiglandular endocrine disease. 相似文献
12.
Report on a case of aneurysm in a child and its treatment with discussion of its rarity and origin. 相似文献
13.
Jochen P?ling Wolfgang Rees Vittorio Mantovani Stephan Klaus Ludger Bahlmann Virgilius Ziaukas Norbert Hübner Henning Warnecke 《European journal of cardio-thoracic surgery》2006,30(4):597-603
BACKGROUND: For the first time, microdialysis was used to investigate in vivo and online the myocardial metabolism during and after cardiac surgery in patients treated with two different methods of myocardial protection. METHODS: Thirty patients underwent standard CABG with one of two different methods of myocardial protection. The patients were randomised to receive either cold blood (COLD group) or warm modified Calafiore cardioplegia (WARM group). Microdialysis probes were implanted into the myocardium of left ventricular apical region of the heart. Cardioplegia was given antegrade only. Microdialysis measurements were performed at time intervals before, during and 24 h after cardiopulmonary bypass and analysed for glucose, lactate, pyruvate and glycerol. RESULTS: Myocardial lactate concentrations were significantly higher in the WARM group compared with that of the COLD group, while serum lactate was comparable. Glycerol was significantly higher at the end of the clamping time in the WARM group. At the same time the glucose-lactate ratio as a marker of nutritional disorder had significantly lower levels in the WARM group. The cumulative CK-MB release over 24 h was significantly higher in those hearts protected with warm blood. CONCLUSIONS: The oxidative stress measured was significantly higher in patients undergoing CABG using modified Calafiore cardioplegia, whereas the cold cardioplegia minimised the effects of aortic clamping. The results indicate that cold cardioplegia offers superior protection of the heart, in terms of more rapid normalisation of myocardial metabolism. In elective myocardial revascularisation, intermittent antegrade warm blood cardioplegia is a comparable safe method of myocardial protection. However, in patients referring to a long clamping time, advantages of cold cardioplegia for myocardial revascularisation may be magnified. 相似文献
14.
Matthias Bollow Wolfgang Knauf Agnieszka Korfel Matthias Taupitz Andreas Schilling Karl-Jürgen Wolf Bernd Hamm 《Journal of magnetic resonance imaging : JMRI》1997,7(1):241-250
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio. 相似文献
15.
Normal morphology of sacroiliac joints in children: magnetic resonance studies related to age and sex 总被引:2,自引:0,他引:2
M. Bollow J. Braun J. Kannenberg T. Biedermann C. Schauer-Petrowskaja S. Paris S. Mutze B. Hamm 《Skeletal radiology》1997,26(12):697-704
Objective. To determine in a prospective study the normal MRI morphology of the sacroiliac joints (SIJs) in relation to age and sex
during adolescence. Design and patients. A total of 98 children (63 boys, mean age 12.7±2.8 years; 35 girls, mean age 13.7±2.3 years), ranging in age from 8 to 17
years, with juvenile chronic arthritis (JCA) but without signs of sacroiliitis fulfilled the study prerequisites (no back
pain and no pathologic changes of the SIJs on physical examination before MRI in a 1.5-year follow-up). An additional eight
HLA-B27-negative boys and eight HLA-B27-negative girls without arthritis served as controls. The MRI protocol comprised a
T1-weighted SE sequence, an opposed-phase T2*-weighted GE sequence, and a dynamic contrast-enhanced study in single-section
technique. Results. Noncontrast MRI permitted differentiation of “open” from ossified segmental and lateral apophyses of the sacral wings, with
a significant difference in age (P <0.05) between children with open and ossified apophyses. Ossification of the apophyses of the sacral wings was seen significantly
earlier (P <0.05) in girls than in boys. Girls also had a significantly higher incidence of transitional lumbosacral vertebrae, pelvic
asymmetries, and accessory joints. In the contrast-enhanced opposed-phase MRI study, normal cartilage of the SIJs showed no
contrast enhancement whereas the joint capsule showed a moderate enhancement. Conclusion. There are significant age- and sex-related differences in the normal MRI morphology of juvenile SIJs. Our findings might
serve as a standard of comparison for the evaluation of pathologic changes – in particular for the early identification of
juvenile sacroiliitis. 相似文献
16.
Understanding the pathologic Haglund's deformity 总被引:1,自引:0,他引:1
Pathologic conditions behind the calcaneus are common, and may initiate during early childhood. The authors discuss osseous and soft tissue conditions involving the posterior-superior surface of the heel. Radiographic and clinical evaluation is considered. Treatment alternatives are also reviewed. 相似文献
17.
C W Hamm J H Robertson J T Robertson D K Hathaway E Tolley 《The Journal of neuroscience nursing》1988,20(5):303-308
Cardiovascular changes have been noted to occur during movement from the operating room or recovery room (RR) to the intensive care unit (ICU). This study examined blood pressure changes and related variables during transport from the RR to the ICU in 135 postoperative acoustic tumor patients. Although there was no significant change in blood pressure values from the RR to the ICU, patients with pre-existing hypertension and elevated RR blood pressures were noted to have an increased frequency of postoperative complications. In addition, a relationship was noted between administration of halothane and frequency of postoperative complications. Results highlight the need for nurses not only to monitor, but also closely control postoperative blood pressure in this population. 相似文献
18.
Lise Pedersen Susanne Holck Torben Schiødt Karin Zedeler Henning T. Mouridsen 《Breast cancer research and treatment》1989,14(1):91-99
Summary One hundred thirty-one breast carcinomas with medullary features, registered in the Danish Breast Cancer Cooperative Group from 1977–1982, have been histopathologically reviewed by two senior pathologists and classified as typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), and non-medullary carcinoma (NMC). Diagnostic criteria were based on those put forward by Ridolfiet al. and Fisheret al. The procedure was repeated with an interval of about one year by both pathologists. The diagnostic interobserver agreement was 72% with a Kappa of 0.55. The intraobserver agreement was 77% and 63% with Kappa values of 0.64 and 0.44, respectively. To see whether the observed inter- and intraobserver variability had any prognostic implications, diagnostic subgroups for both pathologists were analyzed with Kaplan Meier plots for recurrence-free survival (RFS) and with log rank tests. In the first evaluation pathologist 1 segregated a group of TMC with a significantly better RFS than for the NMC group, and pathologist 2 segregated a group of TMC with a corresponding strong trend. These findings could not, however, be reproduced in the second evaluation. The study indicates that the criteria of TMC and AMC as proposed by Ridolfiet al. need to be sharpened and simplified in order to reduce inter-and intraobserver variability. Larger studies with a control group of infiltrating ductal carcinomas are mandatory to elucidate the clinical importance of the diagnoses of Typical and Atypical Medullary Carcinoma of the breast. 相似文献
19.
A cytoskeletal actin gene in the mosquito Anopheles gambiae 总被引:2,自引:0,他引:2
C. E. Salazar D. Mills Hamm D. M. Wesson C. B. Beard V. Kumar F. H. Collins 《Insect molecular biology》1994,3(1):1-13
Five actin genes have been identified in the mosquito Anopheles gambiae , and a constitutively expressed actin gene has been chosen for detailed analysis. We have physically mapped and sequenced this gene and six associated cDNAs, including translated coding regions, as well as the 5 and 3 flanking sequences. Analysis of stage-specific RNA shows this gene to be present in all stages of mosquito development and in an established A. gambiae cell line, thus indicating a cytoskeietal actin. In the sequence of the translated coding region and in pattern of expression, this gene is very similar to the cytoskeietal actin genes of Droso-phila melanogaster , and in sequence, equally similar to the Artemia cytoskeietal actin gene 403 (99.2% identity among the three amino acid sequences). Sequencing of this A. gambiae actin gene (designated actWior its location in chromosome division 1D) and selected cDNAs shows that it possesses three alternative leader sequences; thus the gene appears to have three alternative promoters. These promoters should ultimately prove useful in the production of transgenic constructs for constitutive expression. 相似文献
20.
Ralf-Peter Vonberg Sabine Stamm-Balderjahn Sonja Hansen Irina Zuschneid Henning Ruden Michael Behnke Petra Gastmeier 《Infection control and hospital epidemiology》2006,27(10):1123-1127
A systematic search was performed to identify outbreaks of methicillin-resistant Staphylococcus aureus infection and colonization caused by healthcare workers (HCWs). Of 191 outbreaks identified, 11 had strong epidemiological evidence that HCWs were the source. In 3 of these outbreaks, asymptomatic carriers were the cause. The frequent practice of screening asymptomatic HCWs should be reconsidered. 相似文献