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991.
992.
Elevated production of anti-DNA antibody in patients with systemic lupus erythematosus (SLE) is a central problem in the pathogenesis of tissue injury. In the present study, we attempted to manipulate anti-DNA antibody production through the antigen-cytotoxic drug conjugates, DNA-daunorubicin complexes. The effect of DNA-daunorubicin complexes was determined by examining SLE lymphocytes for spontaneous in vitro production of anti-DNA antibody. These complexes, at 2 μg/ml, suppressed anti-DNA antibody production, but not total IgG production, which suggests that specific suppression of anti-DNA antibody production was achieved at this concentration. We believe that the DNA-daunorubicin complexes affected mainly B cells, since such suppression was obtained by treating B cells, as well as B plus T cells. Furthermore, the complexes had no effect on the proliferative responses of SLE T cells to DNA, phytohemagglutinin, or concanavalin A. These results indicate that DNA-daunorubicin complexes may have the potential for selectively suppressing anti-DNA antibody production in patients with SLE.  相似文献   
993.
994.
A variety of disturbances in thermoregulatory processes have been identified in patients with anorexia nervosa (AN). Malnutrition, loss of thermal insulation, and hypoglycemia are generally accepted as the principal underlying mechanisms. Many of these thermoregulatory aberrations, however, may persist beyond the period of malnutrition and after substantial gains in body weight (in particular, hypothermia and an absence of shivering). It is proposed that during the course of the illness a physiologic state similar to that of cold-adapted mammals may occur in AN patients. As a consequence of this aberrant physiologic state we postulate that an increase in functional nonshivering thermogenesis (NST) interferes with normal shivering responses to cold. An increase in functional brown adipose tissue is proposed to underlie the development of NST in AN patients.  相似文献   
995.
Objective Systemic sclerosis (SSc) is defined as an autoimmune disease presenting with fibrosis of various organs and vascular endothelial damage. Vascular lesions, including small-bowel angioectasias, are also frequently detected in SSc patients. Polidocanol injection (PDI) is a safe and effective hemostatic treatment for gastrointestinal bleeding. We evaluated the outcomes of PDI for small-bowel angioectasia in SSc patients. Methods We retrospectively evaluated 65 consecutive SSc patients (61 women; mean age, 64.3 years old) who underwent capsule endoscopy (CE) and/or double-balloon endoscopy at Hiroshima University Hospital between April 2012 and December 2019. Patients Patients were stratified according to the presence of small-bowel angioectasia. Among patients who underwent CE during the same period, those with small-bowel angioectasia without concomitant diseases were compared with SSc patients with small-bowel angioectasia. Clinical and endoscopic characteristics, treatment outcomes, and the incidence of metachronous small-bowel angioectasia after PDI were evaluated. Results SSc patients with small-bowel angioectasia exhibited significantly lower hemoglobin levels and a significantly higher incidence of skin telangiectasia than those without small-bowel angioectasia. On a multivariate analysis of the presence of small-bowel angioectasia, anemia and skin telangiectasia were significant independent factors. SSc patients with small-bowel angioectasia included a higher proportion of women and exhibited a significantly higher incidence of metachronous small-bowel angioectasia than X. The characteristics of small-bowel angioectasia and outcomes of PDI were not significantly different between the two groups. No post-treatment rebleeding cases or adverse events were noted. Conclusion CE should be performed for SSc patients with anemia and/or skin telangiectasia. PDI is effective for SSc patients with small-bowel angioectasia.  相似文献   
996.
Multilayered films prepared from graphene oxide (GO) subjected to a single oxidation process (1GO) can actuate in response to moisture, whereas those prepared from GO subjected to two oxidation processes (2GO) lose this ability. To elucidate the origin of this difference, the structures and properties of various multilayered films and their contents were analyzed. According to atomic force microscopy images, the lateral size of the GO monolayer in 2GO (2.0 ± 0.4 μm) was smaller than that in 1GO (3.2 ± 0.4 μm), although this size difference did not affect actuation. Scanning electron microscopy images of the cross sections of both films showed fine multilayered structures and X-ray diffraction measurements showed the moisture sensitive reversible change in the interlayer distances for both films. Both films adsorbed 30 wt% moisture in 60 s with different water contents at the bottom moist sides and top air sides of the films. Nanoindentation experiments showed hardness values (1GO: 156 ± 67 MPa; 2GO: 189 ± 97 MPa) and elastic modulus values (1GO: 4.7 ± 1.7 GPa; 2GO: 5.8 ± 3.2 GPa) typical of GO, with no substantial difference between the films. On the contrary, the 1GO film bent when subjected to a weight equal to its own weight, whereas the 2GO film did not. Such differences in the macroscopic hardness of GO films can affect their moisture-induced actuation ability.

The moisture-induced actuation behavior of graphene oxide (GO) thin films was found to depend on their extent of oxidation.  相似文献   
997.
Three Japanese adolescents with chronic hepatitis C were treated by direct‐acting antivirals (DAAs). No adverse events or laboratory abnormalities were observed during and after DAA therapy, and a sustained virological response was achieved in all cases. The emotional functioning of the patients and their mothers were improved after DAA therapy.  相似文献   
998.
Ketogenic diets, which are carbohydrate-restricted high-fat diets, may have therapeutic effects on various diseases, including cancer. However, ketogenic diets are often not standardized and, therefore, results are difficult to interpret. We previously investigated the usefulness of ketogenic diets in cancer therapy, where ketogenic formulas (KF) were used as supplements to enhance blood ketone bodies; however, the amount of KF was determined empirically with reference to blood ketone bodies levels. Here, to determine a standardized optimal amount of KF, we investigated temporal changes in blood ketone bodies (acetoacetic acid (AcAc), β-hydroxybutyrate (BHB)) and safety in 20 healthy individuals when KF was taken repeatedly under the conditions of a ketogenic diet (UMIN000034216). The diurnal variation in total ketone bodies, and AcAc and BHB levels significantly increased after lunch and after dinner, on the 4th day of KF administration. There were no significant safety issues related to KF in the context of anthropometric, metabolic, nutritional, urological and gastrointestinal parameters. In addition, ketogenic diets lead to changes in gut microbiota. KF showed a decrease in phylum Firmicutes. Our study provides baseline data of the usefulness of KF in a ketogenic diet.  相似文献   
999.
Cholesterol and bile acid leves were examined in young (8 weeks), middle-aged (12 months) and old (24 months) germ-free male rats, and young (8 weeks) and middle-aged (12 months) conventional male rats. The plasma cholesterol levels were higher in the aged rats, being more marked in the conventional rats. The liver cholesterol levels also increased with age and the increases were almost identical for both groups. No age-related changes were found in the biliary bile acid secretion, the pool size and distribution of bile acids in the bile, small intestine and large intestine, nor in the turnover frequency of bile acids, but the pool size in the young and middle-aged germ-free rats was much larger than that in the conventional rats. The turnover frequency was less in the germ-free rats. The bile acid synthesis presumed from the fecal bile acid excretion decreased in the aged germ-free rats but not in the conventional rats. A most remarkable age-related change was found in the bile acid composition; cholic acid increased and beta-muricholic acid derived from chenodeoxycholic acid in the rat decreased by aging, resulting in an increase of the CA/CDCA ratio (bile acids belonging to the cholic acid group/bile acids to the chenodeoxycholic acid group) in the bile, feces and pool. These results suggest that cholic acid synthesis increases while chenodeoxycholic acid synthesis is impaired by aging in rats.  相似文献   
1000.
The pathophysiological changes associated with hypothermia were investigated in the rat stomach under anesthetized conditions. The animal was placed in a styrene foam box and the core body temperature was kept between 24 and 36°C using a heat lamp and refrigerant pack. Lowering of body temperature (<30°C) produced acid hypersecretion and induced hemorrhagic lesions in the gastric mucosa; these responses reached the maximum at 28°C, and a significant relationship was found between acid output and lesion score. Hypothermia (28°C) also caused a marked increase of gastric contractile activity and mucosal blood flow (MBF), but the ratio of acid output to MBF became greater when compared to that obtained under normothermic conditions. These changes induced by hypothermia (28°C) were completely blocked by vagotomy and were significantly inhibited by atropine, hexamethonium, clonidine, or TRH antiserum. However, lowering body temperature did not significantly affect acid secretory, motility, and ulcerogenic responses induced by carbachol in the vagotomized rat, excluding local mechanisms (suppression of the inhibitory nerves) in the hypothermia-induced changes. We conclude that hypothermia alone stimulates vagally dependent acid secretion and motility, resulting in damage in the gastric mucosa. These changes may be centrally mediated by TRH, which is released in association with the thermogenic response to hypothermia.  相似文献   
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