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131.
OBJECTIVE: Some patients develop an eating disorder at a late age. It is worth investigating why this syndrome develops at such widely different ages. METHODS: Two Japanese cases of late onset anorexia nervosa are reported. RESULTS: In these late onset cases, anorexia developed out of sadness over a loss such as bereavement, divorce, and fear or anxiety for the future. In addition, these two patients didn't demonstrate a fear of aging or of losing their attractiveness and sexuality, nor did they develop a dissociative disturbance based on an early traumatic history of sexual abuse in PTSD. CONCLUSION: Although the clinical features are similar, there appear to be differences between late onset and adolescent cases in psychological mechanisms.  相似文献   
132.
INTRODUCTION: Transient T wave changes after cessation of preexcitation have been attributed to cardiac memory. However, there have been no reports on the effects of long-term cardiac memory on repolarization dispersion before and after catheter ablation in patients with Wolff-Parkinson-White (WPW) syndrome. METHODS AND RESULTS: We investigated 47 patients with an accessory pathway (AP; 24 manifest left-sided, 14 manifest right-sided, and 9 concealed left-sided). Repolarization dispersion was analyzed by two methods, recovery time (RT) dispersion and newly proposed T wave width (WT), from 87-lead body surface maps before, 1 day after, and 7 days after catheter ablation. RT dispersion and WT were significantly correlated before, 1 day after, and 7 days after catheter ablation (r = 0.78). In patients with preexcitation, RT dispersion and WT increased significantly (P < 0.05) 1 day after catheter ablation (178 +/- 32 msec and 172 +/- 30 msec) compared with those before (154 +/- 24 msec and 156 +/- 18 msec) and 7 days after catheter ablation (147 +/- 19 msec and 156 +/- 16 msec), respectively. However, there were no significant changes in RT dispersion and WT before and after catheter ablation in concealed WPW syndrome. CONCLUSION: The findings suggest that the abrupt changes in activation sequence increase repolarization dispersion in the presence of previous cardiac memory, and that the dispersion decreases days or weeks after alteration of activation sequence by catheter ablation, with development of new cardiac memory in patients with manifest WPW syndrome.  相似文献   
133.
Are We Lost in the Labyrinth of the Sinoatrial Node Pacemaker Mechanism?   总被引:3,自引:0,他引:3  
Despite extensive electrophysiologic studies performed to date, the ionic mechanisms of sinoatrial node pacemaker activity are unclear. This article highlights three recent topics associated with this issue: (1) sustained inward current (Ist)); (2) the role of Ca2+ release from the sarcoplasmic reticulum; and (3) the role of L-type Ca2+ current (I(Ca,L)). New observations on these topics seem to make the scenario of the pacemaker mechanism increasingly complex. However, such complexity and diversity of ionic events and their orchestration may be important for the sinoatrial node to perform its robust pacemaking activity under a variety of pathophysiologic circumstances.  相似文献   
134.
We describe a case of false aneurysm due to loosening of the anastomotic sutures 5 years after graft replacement for subacute type A aortic dissection. Leakage from the graft was controlled by tightening the suture slack indicating that suture loosening was the cause of the aneurysm. The mechanism was probably the progressive thinning of the edematous swollen aortic wall over the years causing the sutures to loosen.  相似文献   
135.
136.
Anti-tumor immune responses are considered to be one of the key host reactions in human colorectal cancer, with T cells as important effector cells. For the induction of tumor-specific immunity, processing of cancer cells and pruning of T cells by antigen-presenting cells are important. The present study was designed to clarify the relationship between Fas ligand (FasL; CD95L) expression and apoptotic cancer cells. Immunohistochemistry using frozen sections taken from 58 patients with colorectal cancer revealed that stromal cells composed mainly of tumor-associated macrophages expressed FasL, leaving cancer cells negative for FasL. These macrophages were abundantly distributed along the invasive margin. In situ hybridization revealed that these macrophages as well as cancer cells expressed FasL mRNA, whereas macrophages in the normal colon mucosa rarely expressed FasL. Apoptotic cancer cells recognized by monoclonal antibody M30 CytoDEATH were localized not only in cancer cell nests, but also in the stroma along the invasive margin showing a dissociated pattern, which was particularly evident in the areas of FasL+ macrophages. Furthermore, these macrophages, phenotypically similar to dendritic cells, occasionally contained M30+ apoptotic cancer cells in the cytoplasm. Clinicopathologic analyses in 123 cases revealed 1) a positive correlation between the degree of dissociated M30+ apoptotic cancer cells and the number of macrophages along the invasive margin and 2) an inverse association between the degree of dissociated M30+ apoptotic cancer cells and the occurrence of hematogenous metastasis after surgical resection of the primary tumor. In conclusion, the present study shows the impor- tance of FasL+ activated macrophages as one of the host defense mechanisms against cancer cell spread in human colorectal cancer.  相似文献   
137.
A nucleotide polymorphism of C or T was detected at position 465 in the sex-determining region Y (SRY) gene. To evaluate the utility of this dimorphism in human population studies, the frequency and the frequency of the haplotype combined with the two polymorphic loci YAP and M9 were examined in a total of 130 unrelated Japanese and 130 unrelated German males. The T nucleotide was found in 24.6% (32/130) of the Japanese but not in any of the 130 German males. Accordingly, four of the eight possible combination haplotypes of SRY/YAP/M9 were identified in the Japanese population, but one of the four haplotypes comprising SRY(T) was absent in the German samples. This suggests that the C to T transition may be more recent than the YAP insertion or the M9 transversion and the change might have occurred in an ancestral Asian population. These results imply that the dimorphism at the SRY gene is one of the Y-linked markers useful for human population studies and also for ethnic identification of forensic samples. Received: 9 March 1999 / Accepted: 9 September 1999  相似文献   
138.
Since loss of heterozygosity on 8p22-p21,3 has been found frequently in prostate cancer, the status of a candidate tumor suppressor gene named PRLTS gene, recently cloned from the same region in some human malignancies, was examined in the present study. DNAs were isolated from 69 Japanese prostate cancer patients (37 localized and 32 cancer-death cases). Loss of heterozygosity at this gene locus was observed in 15 of 36 (42%) localized prostate cancer patients and 22 of 32 (69%) cancer-death patients. One cancer-death patient had a missense mutation, ACG→ATG (Thr→Met) at codon 64 in metastatic tumor tissues of pelvic lymph node and liver, and these tissues showed loss of the homologous allele, indicating that "two-hit" mutation of the PRLTS gene had occurred in this case. The others did not show any mutation, regardless of the presence or absence of loss of heterozygosity. Although loss of heterozygosity at the PRLTS gene locus is a relatively common abnormality, mutation of this gene is rare in prostate cancer.  相似文献   
139.
To elucidate genetic alteration in relation to morphology and also to confirm more directly the proposed adenoma-carcinoma sequence, we analyzed thirty-eight colorectal "cancer in adenoma" lesions exhibiting areas of different atypia, in terms of K- ras codon 12 point mutation. The mutation incidence was 26.3% (10/38) for all cancerous areas. Well-differentiated and very well-differentiated carcinoma exhibited values of 17.6% (3/17) and 30.4% (7/23), respectively (statistically not significant). Positive cases of adenoma with severe atypia and adenoma with moderate or slight atypia were 26.7% (8/30) and 8.3% (3/36) respectively (statistically significant). Thus, K- ras point mutation, as indicated previously, may play an important role in the early stages of colorectal tumorigenesis. As for the nature of the mutation, GGT(Gly) to GAT(Asp) was the most frequent (80%). Eight cases had mutations concurrently in different areas of the same tumor and in all of these the mutation was homogeneous (6 cases to GAT, 1 case to TGT and 1 case to GTT). This provides genetic support for the "adenoma-carcinoma sequence" theory proposed on the basis of morphological considerations. All lesions with a mutation were of polypoid type, and no mutation was found in the flat type.  相似文献   
140.
The anatomy of the facial nerve relative to its intratemporal and extratemporal courses varies over time with developmental changes. Otologic and parotid surgery in infants and children demands detailed knowledge of the precise anatomy of the facial nerve with respect to the tympanic ring and external auditory canal, The authors analyzed this area using our three-dimensional (3-D) computer-aided reconstruction and measurement method studying the spatial relations of the facial nerve to the tympanic ring and stylomastoid foramen. Temporal bones from five normal individuals aged 36 gestational weeks, 3 months, 8 months, 4 years, and 17 years were retrieved from the temporal bone collection stored at the Elizabeth McCullough Knowles Otopathology Laboratory in Pittsburgh. Three-dimensional reconstruction of the facial nerve comparing the developmental anatomy across the various age groups provides the surgeon with the technical information necessary to address problems in this area.  相似文献   
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