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21.
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.  相似文献   
22.
H Kuwano  H Takano  K Sugimachi 《Endoscopy》1989,21(4):188-190
We treated a male teenager with a solitary gastric Peutz-Jeghers type (hamartomatous) polyp showing neither mucocutaneous pigmentation nor inheritance. X-ray studies of the upper gastro-intestinal tract, small intestine and barium enema revealed a solitary thumb tip-sized polypoid mass in the posterior wall of the gastric body, with no evidence of any associated lesion. Histologically, the polypoid mass showed typical features of a Peutz-Jeghers type (hamartomatous) polyp. This may be the first documentation of a "solitary" gastric Peutz-Jeghers type polyp, in the absence of familial polyposis coli and mucocutaneous pigmentation.  相似文献   
23.
Recent data have shown the existence of specific changes in mRNAs in thyroid carcinomas. It has not been clarified, however, why these changes clearly distinguish benign tissues from carcinomas, while genomic alternation such as mutations in the RAS or P53 genes do not. Further, the widely believed hypothesis, multi-step carcinogenesis, does not explain some clinical and experimental evidence of thyroid carcinomas. Considering these facts, we propose a new idea for thyroid carcinogenesis called "germ-cell carcinogenesis", in which cancer cells are derived from the remnant of fetal thyroid germ cells(thyroblasts) instead of normal thyroid follicular cells. Utilizing such mRNAs, we have established a new method for preoperative molecular-based diagnosis of thyroid carcinomas, Aspiration Biopsy Nucleic Acid Diagnosis(ABND). ABND allows us to perform preoperative nucleic acid analyses of the tumors by extracting RNAs or DNAs from tumor cells obtained by fine needle aspiration biopsies(FNABs). Pathological diagnosis of thyroid follicular carcinoma is quite difficult, and the establishment of preoperative molecular-based diagnosis of follicular carcinoma has been long expected. We found that quantification of the trefoil factor 3(TFF3)/galectin-3 mRNA ratio in thyroid tumor cells is a useful tool for distinction between follicular adenomas and carcinomas. Because ABND can be performed without any severe invasion to the patients, in the near future, when more reliable systems of quantitative RNA analysis have been developed, ABND will probably become one of the standard tests for preoperative diagnosis of thyroid carcinoma.  相似文献   
24.
25.
Summary Various doses of tetanus toxin were injected into three hind leg and two fore leg muscles of the rat. The neuromuscular transmission was tested by recording the mass action potential of the muscles elicited by a single electrical stimulus to the motor nerve after strong symptoms of local tetanus had developed. The muscle responses were depressed and blocked at lower toxin doses in the fast tibialis anterior than in the mixed gastrocnemius latemlis, while blocking of the slow soleus required the highest dose. The extensor carpi radialis and the flexor carpi ulnaris muscles showed medium sensitivity. In all five muscles the contraction time was measured and correlated with its individual minimal blocking dose. The more phasic (i.e., the faster) the muscle, the more sensitive its neuromuscular transmission was to tetanus toxin. The proportional distribution of red, white, and intermediate fibres, which are associated with specific end-plate types, was evaluated for the five muscles. The percentage of white fibres in the muscles displayed a very good negative correlation with the blocking dose. The relation between structures of end-plates and effects of tetanus toxin were analysed and it is suggested that the differences in sensitivity to tetanus toxin in the neuromuscular transmission in the five muscles is determined by a differential distribution of endplates with varying sensitivities to this toxin due to structural properties.This study is a part of a doctoral dissertation submitted by one of the authors (H.K.) to the Faculty of Medicine, University of Göttingen. Some of the results were presented at the 48th and 49th Congr. of German Physiol. Soc. (Kretzschmar et al., 1977, 1978) and at the 5th Internat. Conf. on Tetanus (Kretzschmar et al., 1979)  相似文献   
26.
Monoclonal antibody 303 (mAb 303) reacts with the high molecular weight agglutinin present in human saliva. Its reactivity is periodate sensitive, and it has been shown to recognize the Y epitope. Immunogold labeling of thin sections of human parotid and submandibular glands with mAb 303 showed reactivity in secretory granules of serous acinar, intercalated and striated duct cells (Takano et al., 1988). We now report that the apical and basolateral membranes of salivary acinar and duct cells are labeled by mAb 303, but not myoepithelial cells, endothelial cells and other mesenchymal cells. Gold particles were confined to acinar and duct cell membranes even when myoepithelial cells were directly adjacent, suggesting that the epitope resides on a membrane glycoprotein and that the label does not represent secreted agglutinin bound to the cell surface. Although myoepithelial cells are thought to differentiate from epithelial stem cells, the present results indicate that substantial compositional differences exist between the membranes of myoepithelial cells and other salivary parenchymal cells. Earlier studies also showed that mAb 303 labels normal pancreatic acinar cells and certain salivary (pleomorphic adenoma) and mammary (lactating adenoma) tumors (Bogert et al., 1988). This antibody thus may be a useful reagent for characterizing the origin of exocrine gland-derived cell cultures and neoplastic cells. Further, localization studies may provide insight into the role of the Lewis blood group-related epitope in secretory cells.  相似文献   
27.
Immunoglobulin G (IgG) in six out of 30 patients with systemic lupus erythematosus (SLE) strongly inhibited the activity of RNA-dependent DNA polymerase (RDPase) of baboon endogenous virus, M7, while IgG obtained from scleroderma patients, rheumatoid arthritis patients and normal subjects was less reactive. Experiments with anti-human IgG and with IgG F (ab')2-bound immunoaffinity columns indicated that the inhibition of RDPase was antibody-mediated. The RDPase inhibiting activity of SLE IgG was considered not to be due to cross-reactions of anti-nuclear antibodies including anti-DNA, anti-ribonucleoprotein, anti-Sm and anti-SS.B antibodies. SLE IgG preferably inhibited the RDPase activity of baboon endogenous virus and a feline endogenous virus, RD114. These findings support the hypothesis that retrovirus(es) might be involved in SLE.  相似文献   
28.
Summary The fine structure of intracellular and extracellular lipids in the atherosclerotic aorta of Watanabe-heritable hyperlipidemic (WHHL) rabbits was demonstrated by a quick-freeze etching technique. Many lipid droplets, with and without a membrane, were observed in the foam cells. Membrane-free droplets were observed as onionlike structure with a concentric lamellar structure surrounded by 10 nm filaments. Droplets surrounded by a limited membrane probably correspond to lipid-laden lysosomes.In the extracellular connective tissue space, marked accumulation of lipids with a vesicular structure was seen among collagen fibers. The appearance of these lipids was similar to that of lipids in lysosomes of foam cells.  相似文献   
29.
The performance of the newly developed implantable centrifugal blood pump was investigated in vitro. The pump was developed with the end goal of building a versatile system that includes a left ventricular assist system with an internal secondary battery or an implantable biventricular assist system with two implantable blood pumps. The hydrodynamic characteristics and efficiency of the blood pump were evaluated, and the mechanical damage to the blood caused by the blood pump was assessed through a hemolysis test using fresh goat blood. The pump could generate 120 mm Hg at a flow rate of 5 L/min and a motor speed of 2,500 rpm. The electric input power to the pump was approximately 5 watts under these working conditions. The hemolysis caused by the pump was a bit higher than that by the former model, but stayed within an acceptable range. Performance of the pump in vitro was considered sufficient for a left ventricular assist device, although further design improvement is necessary in terms of hemolysis and system efficiency to improve biocompatibility of the pump.  相似文献   
30.
Seven early gastric cancers obtained from patients also demonstrating Epstein-Barr virus (EBV)-positive gastric medullary carcinoma with lymphoid infiltration were investigated using a combined polymerase chain reaction (PCR) and in situ hybridization (ISH) approach. Sharing the same background mucosa as gastric medullary cancers, they comprised four intramucosal carcinomas, predominantly well-differentiated adenocarcinomas, and three submucosal carcinomas, histologically showing mixtures of well and poorly differentiated adenocarcinoma. In the three cases of submucosal carcinoma, the presence of EBV was proven by means of both PCR and ISH. However, not all cancer cells were positive for EBV on the basis of ISH examination, in contrast to the large series of gastric carcinoma with lymphoid infiltration previously investigated. All four mucosal carcinomas were EBV-negative. Lymphocyte-determined membrane antigen (LYDMA) monoclonality, performed by PCR, and latent membrane protein-1 (LMP-1) and Epstein-Barr virus (EBNA2) expression, assessed immunohistochemically, were negative in all seven cases. The results suggest that EBV becomes associated with gastric medullary carcinoma with lymphoid infiltration (GMCL) at a relatively early stage of the disease, shortly after the tumour has initially progressed to an invasive form, and plays some role in the manifestation as GMCL.  相似文献   
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