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71.
It is widely reported that cultured vascular smooth muscle cells (CVSMCs) from spontaneously hypertensive rats (SHR) show enhanced proliferation compared with cells from Wistar-Kyoto rats (WKY). The present studies were designed to find out whether this exaggerated proliferation in SHR is determined genetically and, if so, to evaluate the mechanism on the cell cycle. (1) Incorporation of [3H]thymidine into DNA was enhanced in CVSMCs from 3- and 12-week-old SHR compared with WKY but not in CVSMCs from DOCA-salt hypertensive rats compared with the cells from sham-operated rats. (2) DNA synthesis in SHR cells was enhanced further by addition of insulin (which is considered to be a progression factor) but not by arginine-vasopressin (AVP; considered to be a competence factor) or by angiotensin II (AII). On the other hand, insulin, AVP and AII significantly augmented DNA synthesis in WKY cells. (3) Intracellular free calcium concentration was slightly, but significantly, higher in SHR cells. (4) An increase in the population of DNA-synthesizing S-phase cells and decrease in (G2 + M)-phase cells in SHR were observed by flowcytometry. These data suggest (1) that enhanced DNA synthesis in CVSMCs from SHR is determined genetically, (2) that enhanced DNA synthesis in CVSMCs from SHR is largely dependent on an increased proportion of S-phase cells and (3) that this increase in S-phase cells in CVSMCs from SHR could be due to enhanced competence gene expression in SHR cells. (4) The increased intracellular free calcium concentration is compatible with an activation of the inositol-trisphosphate pathway.  相似文献   
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73.
Dynamic motion of the pelvic floor muscles during voiding was analyzed using real‐time magnetic resonance imaging. To evaluate the contraction of the pelvic floor muscles, striated urethral sphincter distance, levator ani muscle thickness and anterior fibromuscular stroma distance were measured. The percent contraction of the striated urethral sphincter from before voiding to just before initiation of voiding was 14% in the normal group and 5% in the voiding dysfunction group. The percent contraction of the anterior fibromuscular stroma from before voiding to just before initiation of voiding was 11% in the normal group and 1% in the voiding dysfunction group; the percent contraction of the muscles was significantly greater in the normal group (P < 0.05). Striated urethral sphincter and anterior fibromuscular stroma contraction at initiation of voiding open the bladder neck and urethra. This plays an important role in the smooth initiation of voiding.  相似文献   
74.
There is currently no reliable and valid multidimensional instrument for measuring psychological symptoms among Japanese university students. The purpose of this pilot study was to translate the Counseling Center Assessment of Psychological Symptoms‐62 (CCAPS‐62) into Japanese and evaluate its validity and reliability. Following robust translation procedures, the CCAPS‐Japanese was created. In the validation study, 2,758 undergraduate students from 11 universities (mean age = 19.08 ± 1.85 years) completed the CCAPS‐Japanese. The results of confirmatory factor analysis supported the theoretical eight‐factor structure model of the CCAPS‐Japanese with the exclusion of seven items. The decision to retain/remove items was made by evaluating factor loadings and model fit indices while considering cultural equivalence and structural validity. Using the finalized 55‐item CCAPS‐Japanese, further analyses demonstrated that the eight subscales had acceptable to good internal consistencies (α = .61–.89). Thus, the tool's validity and reliability were established. The CCAPS‐Japanese may be appropriate for assessing the psychological concerns of Japanese university students.  相似文献   
75.
Innexins in invertebrates are considered to play roles similar to those of connexins and pannexins in vertebrates. However, it remains poorly understood how innexins function in biological phenomena including their function in the nervous systems. Here, we identified inx‐4, a member of the innexin family in C. elegans, by a forward screening of thermotaxis‐defective mutants. The inx‐4 mutants exhibited abnormal migration to a temperature slightly higher than the cultivation temperature, called mild thermophilic behavior. Rescue experiments revealed that INX‐4 acts in the major thermosensory neuron AFD to regulate thermotaxis behavior. INX‐4::GFP fusion protein localized exclusively along axons in AFD neurons. In addition, over‐expression of INX‐4 in AFD neurons induced a cryophilic behavior, which is opposite to inx-4 mutants. Our findings suggest that INX‐4/Innexin in AFD may fine‐tune the execution of thermotaxis behavior when moving to desired temperatures.  相似文献   
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77.
The co-expression of B7.1 (CD80) and intercellular adhesion molecule (ICAM)-1 (CD54) on tumor cells can induce tumor immunity and immunological memory. We show here that the non-immunogenic tumor lines Lewis lung carcinoma and B16F10 melanoma, co-transfected with B7.1 and ICAM-1, induced cytotoxic levels of membrane tumor necrosis factor (TNF) on naive syngeneic T cells within 24 h. Membrane TNF expression, primarily on CD4 cells, was responsible for tumor cell lysis by naive spleen cells and could be completely abolished by anti-TNF antiserum. It is suggested that the strong induction of TNF cytotoxicity may be important in the establishment of tumor immunity.  相似文献   
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79.
An autopsy case of primary choroid plexus adenocarcinoma arising in a 40-year-old female, who was associated with a high serum level of a carbohydrate antigen 19-9 (CA19-9), is herein presented. After a subtotal removal of a tumor in the left lateral ventricle, the serum level of CA19-9 decreased rapidly, and immunohistochemical examinations of tumor tissue specimens obtained at surgery revealed intense reactivity for CA19-9. The present case may be the first example in which a primary choroid plexus carcinoma was shown to produce CA19-9.  相似文献   
80.
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