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931.
932.
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.  相似文献   
933.
934.
1. The mesencephalic nucleus of the trigeminal nerve has been studied using extracellular micro-electrode recording and the constituent cell types identified.2. Two types of unit were found, namely, muscle spindle first order afferents of ipsilateral jaw-closing muscles and mechanoreceptor afferents of ipsilateral maxillary and mandibular teeth.3. No evidence was found for representation of extra-ocular muscle stretch receptors, of temporo-mandibular joint receptors or of tendon organs of jaw muscles.4. Spindle units of each of the jaw-closing muscles were recorded in all parts of the nucleus and there was no evidence of their segregation according to muscle of origin.5. Attempts to classify spindle units by their dynamic response to ramp stretches, their following of high frequency vibration and their interspike interval variability at constant length gave no indication of two populations when fusimotor activity was suppressed.6. Following the injection of suxamethonium, however, units fell into two groups according to their dynamic index. Their behaviour resembled that described for primary and secondary spindle afferents. In data pooled from all of the jaw-closing muscles there were approximately equal numbers of units in each group.  相似文献   
935.
This study was undertaken in order to estimate the incidence of leukemia among Koreans. Medical records were studied of patients with diagnoses of either ICD-9 038 (septicemia), or 204-208 (leukemias), or 284 (aplastic anemia), or 289 (other diseases of the blood and blood-forming organs) in the claims sent in by medical care institutions throughout the country to the Korea Medical Insurance Corporation (KMIC) during the period from January 1, 1986 to December 31, 1987. These records were abstracted in order to identify and confirm new cases of leukemia among the beneficiaries of KMIC, which covers about 10% of the whole Korean population. Using these data from the KMIC, the incidence rates of leukemia among Koreans were estimated as of July 1st, 1986 to June 30, 1987. The crude incidence rate of all types of leukemia among Koreans is estimated to be 3.45 (95% CI; 0.77-9.55) and 2.29 (95% CI; 0.28-7.81) per 100,000 in males and females, respectively. The cumulative rate for the age span 0-64 is 0.25% in males and 0.18% in females, and for the age span 0-74, 0.35% in males and 0.23% in females. The adjusted rates for the standard world population are 3.90 and 2.48 per 100,000 in males and females, respectively. The relative frequencies by type are 51.5% for AML, 21.6% for ALL, 20.2% for CML, and only 1.5% for CLL. The incidence patterns of various types of leukemia, of which this is the first report in Korea, are analyzed and presented.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
936.
The clinicopathologic and immunohistochemical finding of 10 cases of nasal non-Hodgkin's lymphoma (NHL) and 23 cases of Waldeyer's ring NHL were studied. Immunohistochemically, nasal NHL expressed T-cell markers exclusively, whereas the NHL of Waldeyer's ring were of both T-cell (56.5%) and B-cell lineages (43.5%). Angioinvasiveness by tumor cells was exclusively noted in the T-lineage lymphomas. Epithelial hyperplasia, epitheliotropism by tumor cells, and extensive invasion of adjacent normal tissue were more prominent in T-cell lymphomas than in B-cell lymphomas. T-lineage lymphomas showed distant extranodal spread pattern involving the skin, soft tissue, stomach, spleen, and the liver, whereas B-lineage lymphomas tended to localize in the lymph nodes. The survival rate of Nasal NHL was similar to that of Waldeyer's ring NHL. Although not statistically significant because of small sample numbers, immunophenotype, histologic groups of monomorphic lymphoma, and stage had prognostic importance. In general, T-lineage lymphomas presented with a higher stage than B-lineage lymphomas (p < 0.05)-and overall survival was poor. Stage I disease showed a much more favorable prognosis than stage II disease. Monomorphic lymphomas had a shorter survival than polymorphic reticulosis (PR) or lymphomas with features of PR. This result in conjunction with the morphologic transition between them suggested that monomorphic lymphoma may represent the most advanced stage in the spectrum of PR, lymphoma with features of PR, and monomorphic lymphoma.  相似文献   
937.
Patients with retinoblastoma have an increased risk of developing second primary tumors. Only a few examples of sinonasal small cell neoplasms developing after radiation therapy for retinoblastoma have been reported. We report one such case that developed 18 years after treatment for retinoblastoma. Histologic examination revealed a small, blue, round cell tumor without rosettes or cytoplasmic glycogen. Immunohistochemically, the tumor cells were positive for neuron-specific enolase, synaptophysin, and S-100 protein, but negative for epithelial and mesenchymal markers, suggesting that this was a primitive neuroectodermal tumor. Cytogenetic studies of this tumor failed to reveal the chromosome 13 abnormality typical of retinoblastoma and the t(11:22) translocation typical of the group of peripheral neuroepitheliomas.  相似文献   
938.
Serum hepatitis B virus (HBV) DNA was assayed using polymerase chain reaction, in 107 HBsAg-negative normal Chinese subjects. The results showed that eight subjects (7.5%) had HBV DNA. In the subgroup with antibody to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc), 7.3% (5/68) were positive for HBV DNA; HBV DNA was not detected in six individuals with anti-HBs only and in nine with anti-HBc only. In four persons with anti-HBc and anti-HBe, one had HBV DNA. In 20 subjects negative for all hepatitis B serological markers, two (10%) were found to have HBV DNA. This study indicates that serological markers are not adequate to rule out HBV infection, and it further implies that present blood donor screening methods may need improving.  相似文献   
939.
940.
A Monte Carlo based treatment planning system for modulated electron radiation therapy (MERT) is presented. This new variation of intensity modulated radiation therapy (IMRT) utilizes an electron multileaf collimator (eMLC) to deliver non-uniform intensity maps at several electron energies. In this way, conformal dose distributions are delivered to irregular targets located a few centimetres below the surface while sparing deeper-lying normal anatomy. Planning for MERT begins with Monte Carlo generation of electron beamlets. Electrons are transported with proper in-air scattering and the dose is tallied in the phantom for each beamlet. An optimized beamlet plan may be calculated using inverse-planning methods. Step-and-shoot leaf sequences are generated for the intensity maps and dose distributions recalculated using Monte Carlo simulations. Here, scatter and leakage from the leaves are properly accounted for by transporting electrons through the eMLC geometry. The weights for the segments of the plan are re-optimized with the leaf positions fixed and bremsstrahlung leakage and electron scatter doses included. This optimization gives the final optimized plan. It is shown that a significant portion of the calculation time is spent transporting particles in the leaves. However, this is necessary since optimizing segment weights based on a model in which leaf transport is ignored results in an improperly optimized plan with overdosing of target and critical structures. A method of rapidly calculating the bremsstrahlung contribution is presented and shown to be an efficient solution to this problem. A homogeneous model target and a 2D breast plan are presented. The potential use of this tool in clinical planning is discussed.  相似文献   
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