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21.
The effect of the Ca2+-channel antagonist nicardipine on the basal tone of six segments (duodenum, jejunum, ileum, proximal colon, distal colon and rectum) of the guinea-pig intestine has been investigated in muscle preparations. Nicardipine reduced the basal tone of the proximal and distal colon but not of the duodenum, jejunum, ileum and rectum. Similarly, when each segment was incubated in Ca2+-free medium, the basal tone of the proximal and distal colon, but not that of the other four segments, was reduced. The reduced basal tone recovered after cumulative addition of Ca2+ in both colon preparations. The basal tone of the distal colon was partly reduced by tetrodotoxin, atropine and clonidine. Conversely, l -typeCa2+-channel antagonists (Cd2+, verapamil and nicardipine), but not the T-type Ca2+-channel antagonist Ni2+, completely reduced the basal tone of the distal colon. These results indicate that in the regulation of basal tone there are additional regional differences in the effect of Ca2+ influx into the cells from the extracellular fluid which might involve l -type-like Ca2+ channels and might partly be because of neuronal factors.  相似文献   
22.
The factors determining the severity of a Mamushi ( Agkistrodon blomhoffii ) bite were analyzed based on the findings of our 34 cases and those appearing in the published work. It was not possible to forecast the final severity at the time of the patient's arrival and by the initial blood examination data. The maximal creatinine kinase (CK) values elevated proportionally with the time from the bite, and the relation approximated the equation of y = 300χ, where y represents the maximal CK value and χ indicates the time from the bite to the peak of CK level. In the severe cases which required intensive care, the level of the CK deviated remarkably from this line, and could be grossly distinguished from the non-severe cases. The maximal white blood cell (WBC) count also gradually increased in concordance with the time from the bite, and in addition, the WBC count of most of the severe cases exceeded 20 000/µL. This evidence suggests that the rate of the CK value elevation in relation to the time from the bite can be a useful indicator of the severity of a Mamushi bite, and the WBC count also reflects the severity.  相似文献   
23.
BACKGROUND: The antitumor mechanisms of bacillus Calmette-Guérin (BCG) against bladder cancer is still unclear. We previously reported that BCG was internalized by and survived within murine bladder tumor cells (MBT-2) for at least 40 days. In the present study, we investigated the effect of BCG on the surface antigen expression of bladder tumor cells and the characteristics of these cells as antigen-presenting cells in vitro. METHODS: Surface antigen (major histocompatibility complex (MHC) Class II, CD1, CD80 and intercellular adhesion molecule-1 (ICAM-1)) expression on BCG-treated murine (MBT-2) and human (T-24, J82) bladder tumor cells were analyzed using flow cytometry. The production of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) from murine lymphocytes sensitized with BCG or BCG-treated tumor cells were also investigated. RESULTS: The expressions of MHC Class II, CD1, CD80 and ICAM-1 were augmented in all of the bladder tumor cell lines used; however, they were augmented to varying degrees among the cell lines that were treated with live BCG. Heat-killed BCG had little or no effect. When murine lymph node cells sensitized with BCG or BCG-treated MBT-2 cells were cocultured with BCG-treated MBT-2 cells, significant amounts of IL-2 and IFN-gamma were produced in the culture medium. CONCLUSIONS: BCG induced the augmented expression of surface antigens, such as MHC Class II, CD1, CD80 and ICAM-1, of bladder tumor cells. Furthermore, BCG-treated MBT-2 cells could stimulate BCG-sensitized lymphocytes to produce IL-2 and IFN-gamma. These results strongly suggest that bladder tumor cells gained the characteristics and functions of antigen-presenting cells (APC).  相似文献   
24.
25.
Several designs of palatal appliance have been reported for the treatment of craniomandibular disorders. However, the effect of these appliances has not yet been fully clarified. This study aimed to reveal the effect of palatal appliances of different design on masseter muscle activity during sleep.
Four volunteers (three women and one man, mean age 36·0 years) were used in this study. For each subject, four different types of palatal appliances were used. The palatal appliances were (1) horse shoe type (1 mm thick), (2) thin appliance which covered the whole palate (1 mm thick), (3) thick appliance which filled the palatal concavity and (4) appliance with half the thickness of the third appliance.
These appliances were worn for 1 week in a randomized sequence with 1-week interval between each appliance. Right masseter muscle EMG was recorded three nights per week at home. The EMG signal longer than 0·25 s was classified as a burst and a signal shorter than 0·25 s was classified as a brief burst of fragmentary myoclonus (FM).
Mean number of burst per hour for four subjects were 7·99 ± 7·32, 3·52 ± 1·95, 5·90 ± 3·99, 2·87 ± 2·87 and 9·96 ± 6·02 for base line, appliance 1, 2, 3 and 4, respectively. Mean number of FM per hour were 136·86 ± 69·88, 90·53 ± 41·19, 99·49 ± 39·29, 71·66 ± 24·66 and 144·39 ± 42·97, respectively.
From these results, it was suggested that the thick palatal appliance suppressed the masseter muscle activity during sleep most effectively. Also, the results for appliance 4 questioned the concept of placebo effect for non-occlusal appliances.  相似文献   
26.
Solitary juvenile polyps are generally non‐neoplastic hamartomatous polyps. Inflammation is suggested as the cause of proliferation and progression of these polyps, and adenomatous and carcinomatous changes are rare. We report a rare case of a solitary juvenile polyp with malignant transformation that developed in the sigmoid colon of a 12‐year‐old boy. A 3 cm, pedunculated polyp was endoscopically resected, and histologic evaluation revealed the characteristic features of a juvenile polyp. However, mucous‐filled ectatic glandular spaces were lined by mucin‐secreting columnar epithelial cells with atypical change, and an admixture of adenocarcinoma invading the submucosa was confirmed. The histologic features may suggest the involvement of the adenoma–carcinoma sequence in the development of adenocarcinoma in the present case. Although rare, solitary juvenile polyps should develop adenocarcinoma and thorough histologic evaluation of the resected polyps is warranted to identify the adenomatous tissue.  相似文献   
27.
目的通过对脑血管病患者进行BIT检查 ,了解BIT检查中通常检查和行动检查间的相关性。方法对 2 2例脑血管病患者进行BIT检查 ,分析BIT各个项目间的相关性 ,以及共同因子。结果通常检查和行动检查各合计得分在正常界限分以上或以下的患者右半球损伤的 16例中有 14例 ,左半球损伤的患者 6例中有 5例 ,少数病例有分离现象 .对BIT检查中 15个项目两变数间的相关系数进行比较 ,结果有显著性差异 (P <0 .0 5 ) ,但因子分析因病例数少 ,抽出的主因子不显著。结论脑血管病患者BIT检查各个项目间的相关性很强 ,在临床上有实际应用价值。  相似文献   
28.
Abstract Thirty-two patients with liver cirrhosis and ascites were treated by stepped care diuretic treatment as follows: step 1, placed on a 35 mEq sodium diet; step 2, given 400 mg/day of potassium canrenoate in addition to step 1 treatment; step 3, given 40-80 mg/day of furosemide in addition to step 2 treatment. Eleven out of 32 patients (34.4%, group 1) and 12 of 21 patients (57.1%, group 2) lost their ascites at step 1 and step 2, respectively. The remaining nine patients (group 3) required step 3 treatment. Basal urinary sodium excretion and creatinine clearance were significantly lower and β2-microglobulin was significantly higher in group 3 than those in groups 1 and 2. Elevation of basal plasma renin activity and norepinephrine was evident only in group 3. In group 1, urinary sodium excretion decreased after the treatment. In group 2, plasma α-atrial natriuretic polypeptide was lowered and plasma renin activity and norepinephrine were elevated after the treatment. These results suggest that basal renal function and plasma renin activity and norepinephrine levels are useful indices to predict the effect of ascites treatment and that responders to sodium restriction or potassium canrenoate may be in the state of vascular overflow, while non-responders to potassium canrenoate may be in the state of vascular underfilling. In summary, this stepped care treatment is safe without any side effects, although the diuretics themselves may lead to relative vascular underfilling.  相似文献   
29.
We have reported that two aspartyl (Asp-151 and Asp-58) residues in αA-crystallin in human eye lens were inverted to the D-isomer and isomerized to β-aspartyl residues with age. We report here the kinetics of the Asp racemization of three model peptides corresponding to fragments of αA-crystallin: IQTGLD151ATHAER (T18 peptide). TVLD58SGISEVR (T6 peptide) and HFSPED84LTVK (T10 peptide, as a control). The rate constants of the racemization of Asp residues in these peptides were measured at pH 7.0. at five temperatures: 50, 60, 70, 80 and 90 °C. From the Arrhenius equation, we estimated the activation energy (E) of racemization and the time required for the Asp D/L ratio to approximate to 1.0 (D/L ratio of Asp = 0.99) at body temperature. For the peptide T18, E=21.4 kcal/mol and t=13.5 yr. For the peptide T6, E= 26.8 kcal/mol and t= 49.5 yr. For the control peptide T10, E=28.3 kcal/mol and t= 78.1 yr. The racemization rate of Asp in these three peptides is parallel to that of Asp residues in αA-crystallin. The racemization rate of Asp in the T18 peptide was very rapid compared to that in the other peptides. This result also reflects the racemization rate in native αA-crystallin  相似文献   
30.
Diaphragmatic Hernia Induced in Rat Fetuses by Administration of Bisdiamine   总被引:1,自引:0,他引:1  
Administration of N, N'-bis (dichloroacetyl)-l,8-octamethylenediamine, bisdiamine, to pregnant Donryu rats on a single day of gestation induced unilateral and bilateral diaphragmatic hernias in fetuses with high incidence. The protruded liver was not covered with a serous membrane or a muscular layer. Incidence of unilateral diaphragmatic hernia on the left side was high when bisdiamine was administered on day 9 or 13 of gestation, and that on the right side was high when administered on day 12 of gestation. Incidence of bilateral diaphragmatic hernia was high when bisdiamine was administered on day 12 of gestation. Differences in sensitivity to hernia formation according to day of bisdiamine administration between right and left sides may reflect differences in developmental chronology between the two sides. Two distinct times for induction of left diaphragmatic hernia might be attributed to at least two different mechanisms. The present model is expected to help analyzing not only anatomical characteristics of congenital diaphragmatic hernia but also possible mechanisms responsible for their development.  相似文献   
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