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11.
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   
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Partial left ventriculectomy (PLV) was originally introduced as a new surgical approach by patients with an end stage of cardiac disease. Coronary artery bypass grafting (CABG) is a standard procedures used in cardiac surgery. Multichannel ECG (MECG) measurements and body surface mapping (BSM) were used to analyse the normalised beat amplitude power maps (BAM) that reflect an overall cardiac activity. The resulting BAMs show that the amplitude of cardiac signals decrease for approximately 30% after the PLV and stay in the same level during the postoperative monitoring interval while after CABG no significant changes in BAM have been observed. In addition the electrodes from the body surface area above the left ventricle, where surgery was performed, show significant changes in beat amplitudes.  相似文献   
14.
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   
15.
The aim of this study was to evaluate the efficacy and safety of continuous isoproterenol inhalation therapy for asthma attacks in children. We used l-body isoproterenol (Proternol L) in 22 children with 32 episodes of severe attacks. One of them did not respond to this therapy, and two had complications (atelectasis and pneumothorax). Twenty-nine cases were divided into three subgroups according to their clinical scores; A) scores less than or equal to 4, which meant that they were in the early stage of severe attack (n = 9), B) scores 5-6, which meant impending respiratory failure (n = 17), C) scores greater than or equal to 7, which meant respiratory failure (n = 3). The values of SpO2 at the start of this therapy were 94.8, 91.5, 82.0%, respectively. The more severe their attacks were, the lower their SpO2 levels were. The periods until their scores became zero were 0.78, 6.3, 17.2 hours, respectively. There were significant differences between each period respectively (p less than 0.001, p less than 0.01). Heart rates decreased when their symptoms improved, and other adverse effects were not detected. These results suggest that this therapy is effective and safe for children with severe asthma attacks, especially in the early stage.  相似文献   
16.
Mouse epididymides were examined by light and electron microscopy 6, 12, 24 h, 1.5, 2, 3, and 5 days after efferent duct cutting when the mice were 60 days of age. Six hours after operation, the principal cells in the initial segment of the epididymal duct began to degenerate following the disappearance of intraluminal spermatozoa. The degenerated cells increased rapidly and reached their greatest number 24 h, and then decreased to smaller numbers until 48 h. These degenerative changes were followed by the appearance of macrophages in the epithelium, which were first seen 12 h after operation, becoming very frequent at one and 1.5 days, and then decreasing to become rare at 3 and 5 days. The macrophages phagocytosed the degenerated principal cells. The degenerated principal cells were also ingested and digested by undegenerated principal cells and basal cells. The intraepithelial mitotic figures had almost disappeared at 24 h but were frequently observed at 2 days and more so at 3 days. They returned to normal numbers at 5 days. The volume of the initial segment was decreased to one third until the third day. The principal cells in this segment became similar in both light-microscopic appearance and ultrastructures to the cells in the next segment 5 days after efferent duct cutting. The changes were localized only in the initial segment.  相似文献   
17.
Following horseradish peroxidase (HRP) injection into the cephalopharyngeal muscle (CeP), the hyopharyngeal muscle (HP), the thyropharyngeal muscle (TP), the cricopharyngeal muscle (CP) and the cervical esophagus muscle (CE) of the cat, labeled neurons were identified in the nucleus retrofacialis and the rostral part of the nucleus ambiguus ipsilaterally. The rostral end of the labeled cell column was located more rostrally for CeP and HP than for TP, CP and CE. No difference was noted within the former two or within the latter three. The level of the caudal end of the labeled cell column became more caudal in the order of CeP, HP, TP and CP. The caudal end was located more rostral for CE than for TP. The neurons for CE were located more ventro-laterally than those for the other muscles.  相似文献   
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19.
Cell swelling enhances a slowly activating delayed rectifier K(+) current (I(Ks)) in cardiac cells. This investigation was undertaken to determine which of the two structural units reconstituting the I(Ks) channel, KCNQ1 (KvLQT1) and KCNE1 (minK/IsK), plays a key role in the cell swelling-induced I(Ks) enhancement and to dissect a possible involvement of tyrosine phosphorylation therein. KCNQ1 was transiently expressed alone or together with KCNE1 in a heterologous mammalian cell line. Two distinct whole-cell membrane currents were separately observed during the exposure of transfected cells to various degrees of hyposmotic solutions. A hyposmotic challenge (0.7 times control osmolarity) resulted in about a twofold increase not only in the heteromeric KCNQ1/KCNE1, but also in the homomeric KCNQ1 channel currents. There was no significant difference in the incremental ratio of current amplitude in response to hyposmotic stress between the two KCNQ1-related currents, and the cells expressing the heteromeric channels swelled less than those with the homomeric channels or without the exogenous ones. The cell swelling-induced I(Ks) enhancement was not affected by a protein tyrosine kinase (PTK) inhibitor, by genistein (50 microM), or by an inhibitor of phosphotyrosine phosphatase (PTP), orthovanadate (500 microM), or a nonhydrolyzable ATP analogue, AMP-PNP (5 mM). Taken together, it is very likely that KCNQ1 might primarily participate in the I(Ks) enhancement by osmotic cell swelling. The obligatory dependence of the I(Ks) augmentation on PTK activity remained to be demonstrated, at least, in this expression system.  相似文献   
20.
The signal transduction pathways and activation of the MAP kinase or PI3 kinase signaling cascade regulate a variety of cellular processes, including proliferation and differentiation in hepatocytes. To elucidate the mechanisms of signal transmission required for the regulation of gap and tight junctions during DNA synthesis in rat hepatocytes, we determined changes of expression and function of gap and tight junctions of cells grown in primary culture, using inhibitors of signaling pathways for MAP kinase (PD98059) and PI3 kinase (LY294002). During the stimulation of DNA synthesis induced by epidermal growth factor (EGF), immunoreactivity and mRNAs of gap junction protein Cx32 and of tight junction protein claudin-1 markedly decreased with reduction of gap junctional intercellular communication (GJIC) and the fence function of tight junctions. In Western blots, whole-cell lysate of claudin-1 protein decreased and phosphorylated Cx32 protein in the insoluble fraction of Triton X-100 increased during the stimulation of DNA synthesis. During reinhibition of DNA synthesis, the changes of Cx32 and claudin-1 returned to control levels, as did both functions. In treatment with the inhibitors before DNA synthesis, PD98059 inhibited the changes of expression and function of Cx32, but not claudin-1, without inhibition of cell growth, whereas LY294002 completely inhibited cell growth. These findings indicate that the PI3 kinase pathway rather than the MAP kinase pathway plays an important role for EGF-induced proliferation of rat hepatocytes, and that changes of Cx32 in hepatocytes during the stimulation of DNA synthesis may be in part controlled through MAP kinase. Furthermore, Cx32, but not claudin-1, protein may be a target of activated MAP kinase in hepatocytes.  相似文献   
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