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31.
32.
Response to nicotine of adrenal chromaffin cells was studied in suckling and young adult male rats in vivo. When 5 mg/kg of nicotine was injected subcutaneously to 8-week-old rats, the content of adrenaline and noradrenaline in the chromaffin granule fraction decreased about by 36 and 45%, respectively, 2 min after the administration. In electron microscopy, the number of chromaffin granules in the perinuclear region of adrenaline-storing cells decreased markedly. The number of vacuoles, probably produced by membrane recycling resulting from exocytosis, increased significantly in adrenaline- and noradrenaline-storing cells. Omega-shaped profiles (exocytosis) were frequently observed both in adrenaline- and noradrenaline-storing cells. On the other hand, nicotine injection did not significantly alter the catecholamine content in the 21-day-old rat chromaffin granule fraction, although severe convulsion was evoked. In electron microscopy, the changes indicative of exocytosis mentioned above were scarcely observed. Cholinergic nerve fibers of mature appearance were observed in the adrenal medulla of 21-day-old rats. These results indicate that the responsiveness of the chromaffin cells to nicotine in 21-day-old rats differs from that in 8-week-old rats.  相似文献   
33.
Recently, combined therapy using chemotherapy and photodynamic therapy (PDT) has been proposed as a means of improving treatment outcomes. In order to evaluate the efficacy of combined therapy, it is necessary to determine the distribution of the anticancer drug and the photosensitizer. We investigated the use of imaging mass spectrometry (IMS) to simultaneously observe the distributions of an anticancer drug and photosensitizer administered to cancer cells. In particular, we sought to increase the sensitivity of detection of the anticancer drug docetaxel and the photosensitizer protoporphyrin IX (PpIX) by optimizing the ionization-assisting reagents. When we used a matrix consisting of equal weights of a zeolite (NaY5.6) and a conventional organic matrix (6-aza-2-thiothymine) in matrix-assisted laser desorption/ionization, the signal intensity of the sodium-adducted ion of docetaxel (administered at 100 μM) increased about 13-fold. Moreover, we detected docetaxel with the zeolite matrix using the droplet method, and detected PpIX by fluorescence and IMS with α-cyano-4-hydroxycinnamic acid (CHCA) using the spray method.  相似文献   
34.
In recent years, the techniques improving sliding performances have progressed by using coated films possessing superior tribological properties, to reduce the failures of the mechanical elements. Those techniques are often used under severe conditions such as elastohydrodynamic lubrication (EHL). In this paper, numerical three-dimensional analysis of the maximum shear stress applied into the coated film and substrate under a single EHL operating condition was performed with a range of coated film thickness and elastic properties. The strength of coated film as one of those techniques was evaluated numerically, resulting in an optimum design of coated film. As a result, coated films with a larger value of thickness and a smaller modulus of elasticity than that of substrate are preferable.  相似文献   
35.
The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes.  相似文献   
36.
E.S. Otabe  M. Kiuchi  K. Fujino  B. Ni 《低温学》2009,49(6):267-270
A practical Bi-2223 superconducting magnet, working in liquid nitrogen (L.N2), was designed and fabricated. Bi-2223 tape with a critical current of 147 A was prepared by a controlled overpressure (CT-OP) process at 77.3 K in self-field. Ten double-pancake coils were resistively connected by copper terminals. The bore diameter was 54 mm?, the magnet outer diameter was 122 mm?, the height of the magnet was 124 mm, and the weight of the magnet was about 3 kg. The maximum magnetic field at the center of the bore was 0.48 T with an operating current of 50 A. The experimental results agree well with design predictions calculated by finite element method. AC operation was also performed, and no distortion of the voltage waveform was observed. Therefore, this Bi-2223 superconducting magnet is a suitable replacement for copper magnets designed for applications in science and technology.  相似文献   
37.
Ureteral triplication is a rare congenital anomaly of the upper urinary tract. It is reported to be associated with an increased incidence of congenital anomalies as well as a predisposition to infection and calculus formation. We report a case of type 1 variant of ureteral triplication associated with vesicoureteral reflux into lower and mid pole ureters in a solitary kidney. To our knowledge ureteral triplication in a solitary kidney has not been described previously.  相似文献   
38.
This paper describes the feasibility of 1,400 m steel cable-stayed bridges from both structural and economic viewpoints. Because the weight of a steel girder strongly affects the total cost of the bridge, the writers present a procedure to obtain a minimum weight for a girder that ensures safety against static and dynamic instabilities. For static instability, elastoplastic, finite-displacement analysis under in-plane load and elastic, finite-displacement analysis under displacement-dependent wind load are conducted; for dynamic instability, multimodal flutter analysis is carried out. It is shown that static critical wind velocity of lateral torsional buckling governs the dimension of the girder. Finally, the writers briefly compare a cable-stayed bridge with suspension bridge alternatives.  相似文献   
39.
Determining whether there is evidence of underutilization of outpatient mental health care by Department of Defense (DoD) beneficiaries relative to the general population is the purpose of this study. It analyzes data from the 1994-1995 DoD Health Beneficiary Survey and compares the mental health status and usage rates of active duty members and their families with benchmark levels found in the general population. Although the mental health status for the DoD beneficiary population was found to be generally the same as that of the general U.S. population within gender categories, gender-specific usage rates of mental health services of DoD beneficiaries in the groups examined were well below rates recorded for the general population. The concept of psychological readiness is also introduced. Several recommendations for increasing access to mental health care are presented.  相似文献   
40.
BACKGROUND: Neurenteric cysts are rare endothelium-lined structures. Two patients with symptomatic neurenteric cysts at the craniovertebral junction are presented. CASE PRESENTATION: Intermittent progression of neurologic symptoms delayed diagnosis for both patients. In one case, marked enlargement of the cyst was detected on serial imaging studies, and pathological examination of the excised lesion indicated rupture of the cyst. These cysts were totally resected by transoral or suboccipital approaches, as they were not firmly adherent to surrounding neural structures. The diagnosis of neurenteric cyst was confirmed by immunohistochemical analysis of the cyst wall. CONCLUSION: In view of the clinical course of these patients, we recommend early surgical resection of neurenteric cysts located at the craniovertebral junction.  相似文献   
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