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81.
The approach using pyrrolidine enamine as substrate has been studied for this synthesis, and an important catalyst structural feature has been developed. After survey of pyrrolidine-based Br?nsted acid catalyst, tetrazole catalyst (3f) was found to be optimal in synthesis of aminooxy carbonyl compounds in high yields, with complete enantioselectivity not only for aldehydes but also for ketones.  相似文献   
82.
This case report describes the treatment of a skeletal Class III malocclusion with autotransplantation of a cryopreserved tooth. To gain an esthetic facial profile and good occlusion, extraction of bimaxillary premolars and surgical therapy were chosen. The patient had chronic apical periodontitis on the lower left first molar. Although she did not feel any pain in that region, the tooth was considered to have a poor prognosis. Therefore, we cryopreserved the extracted premolars to prepare for autotransplantation in the lower first molar area because the tooth would probably need to be removed in the future. The teeth were frozen by a programmed freezer with a magnetic field (CAS freezer) that was developed for tissue cryopreservation and were cryopreserved in −150°C deep freezer. After 1.5 years of presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy was performed for mandible setback. Improvement of the facial profile and the occlusion were achieved in the retention phase. Six years after the initial visit, the patient had pain on the lower left first molar, and discharge of pus was observed, so we extracted the lower left first molar and autotransplanted the cryopreserved premolar. Three years later, healthy periodontium was observed at the autotransplanted tooth. This case report suggests that long-term cryopreservation of teeth by a CAS freezer is useful for later autotransplantation, and this can be a viable technique to replace missing teeth.  相似文献   
83.
We investigated the changes in energy expenditure during induction therapy in patients with severe or moderate ulcerative colitis. Thirteen patients (10 men, 3 women; mean age, 36.5 years) with ulcerative colitis admitted to the Shiga University Hospital were enrolled in this study. We measured the resting energy expenditure and respiratory quotients of these patients before and after induction therapy with indirect calorimetry. We analyzed the changes of nutritional status and serum inflammatory cytokine levels and also evaluated the relationship between energy metabolism and disease activity by using the Seo index and Lichtiger index. The resting energy expenditure was 26.3 ± 3.8 kcal/kg/day in the active stage and significantly decreased to 23.5 ± 2.4 kcal/kg/day after induction therapy (p<0.01). The resting energy expenditure changed in parallel with the disease activity index and C-reactive protein and inflammatory cytokine levels. The respiratory quotient significantly increased after induction therapy. Thus, moderate to severe ulcerative colitis patients had a hyper-metabolic status, and the energy metabolism of these patients significantly changed after induction therapy. Therefore, we recommend that nutritional management with 30–34 kcal/kg/day (calculated as measured resting energy expenditure × activity factor, 1.3) may be optimal for hospitalized ulcerative colitis patients.  相似文献   
84.
Predicting the short‐term healing progress of pressure ulcers is important for providing timely and appropriate intervention. Although there are some prediction methods available, these are unsuitable for ulcers with abundant necrotic tissue. We aimed to elucidate the relationship between necrotic tissue alteration and protein distributions on ulcers to establish a new prediction method. Thirty‐eight pressure ulcers were retrospectively analyzed. Protein distributions on necrotic tissue were evaluated by the wound blotting at three levels: marker protein positivity, signal patterns (speckled, heterogeneous, or homogeneous), and the occupation of heterogeneous pattern. Peroxidase, alkaline phosphatase, tumor necrosis factor α, and matrix metalloproteinase‐2 were used as marker proteins. One‐week necrotic tissue alteration was classified as liquefaction or nonliquefaction, and associations with protein distributions were analyzed. The peroxidase positivity was significantly higher in the liquefaction than in the nonliquefaction (p = 0.031). In peroxidase‐positive samples, the proportion of nonliquefaction samples was significantly higher in the heterogeneous pattern (p = 0.029). In the heterogeneous‐patterned samples, the proportion of samples with an occupation values greater than the median value tended to be higher in the nonliquefaction (p = 0.087). There was no significant relationship between liquefaction and other markers. Peroxidase positivity predicts 1‐week liquefaction of necrotic tissue, while a heterogeneous pattern indicates nonliquefaction.  相似文献   
85.
86.
The vacuole-type ATPases (V-ATPases) exist in various intracellular compartments of eukaryotic cells to regulate physiological processes by controlling the acidic environment. The crystal structure of the subunit C of Thermus thermophilus V-ATPase, homologous to eukaryotic subunit d of V-ATPases, has been determined at 1.95-A resolution and located into the holoenzyme complex structure obtained by single particle analysis as suggested by the results of subunit cross-linking experiments. The result shows that V-ATPase is substantially longer than the related F-type ATPase, due to the insertion of subunit C between the V(1) (soluble) and the V(o) (membrane bound) domains. Subunit C, attached to the V(o) domain, seems to have a socket like function in attaching the central-stalk subunits of the V(1) domain. This architecture seems essential for the reversible association/dissociation of the V(1) and the V(o) domains, unique for V-ATPase activity regulation.  相似文献   
87.
88.
The aim of this study was to determine the effect of different concentrations of table salt (NaCl) and ethanol (v/v) solutions on the viability of Alaria alata mesocercariae. Furthermore, the survival of A. alata mesocercariae during simulated human gastric digestion was evaluated. For this purpose, A. alata mesocercariae migration technique (AMT) was used for the isolation of the parasite from high-positive A. alata mesocercariae meat from wild boar, raccoon, raccoon dog, and badger meat. In total, we have studied the behavior of 582 larvae under different conditions (NaCl, ethanol, and artificial gastric juice) in three independent in vitro experiments. The larvae survived at a NaCl concentration of up to 2.0 % until day 21 with a median survival time of 11 days. At 3.0 % NaCl concentration, the larvae lost their vitality after less than 24 h. In addition, it was found that ethanol concentrations from 8.0 to 70.0 % were effective at reducing survival of A. alata mesocercariae within a short period of time (<1 min). Finally, our studies have revealed that it required 120 min to reliably inactivate all A. alata mesocercariae within HCl-pepsin digestion solution with a pH of 1.5–2.0 at 37 °C. Consequently, the results showed that 3.0 % is the minimum concentration of NaCl in meat products recommended for human consumption because at lower NaCl concentration the parasite survived for a substantial period of time. Finally, the common concentrations of ethanol used for the disinfection of surfaces in household and/or laboratory, are sufficient for the inactivation of A. alata mesocercariae.  相似文献   
89.
Several epidemiological studies have indicated that there is a relationship between sleep habits, such as sleep duration, bedtime and bedtime regularity, and mental health status, including depression and anxiety in adolescents. However, it is still to be clarified whether the relationship is direct cause‐and‐effect or mediated by the influence of genetic and other traits, i.e. quasi‐correlation. To examine this issue, we conducted a twin study using a total of 314 data for monozygotic twins from a longitudinal survey of sleep habits and mental health status conducted in a unified junior and senior high school (grades 7–12), located in Tokyo, Japan. Three‐level hierarchical linear model analysis showed that both bedtime and sleep duration had significant associations with the Japanese version of the 12‐item General Health Questionnaire (GHQ‐12) score, suicidal thoughts and the experience of self‐harm behaviours when genetic factors and shared environmental factors, which were completely shared between co‐twins, were controlled for. These associations were statistically significant even after controlling for bedtime regularity, which was also associated significantly with the GHQ‐12 score. These suggest that the associations between sleep habits and mental health status were still statistically significant after controlling for the influence of genetic and shared environmental factors of twins, and that there may be a direct cause‐and‐effect in the relationship in adolescents. Thus, late bedtime and short sleep duration could predict subsequent development of depression and anxiety, including suicidal or self‐injury risk. This suggests that poor mental health status in adolescents might be improved by health education and intervention concerning sleep and lifestyle habits.  相似文献   
90.
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