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81.
This study investigated the changes in nitric oxide (NO) together with inducible nitric oxide synthase (iNOS) content and enzyme activity at 0, 4, 12, 24, and 48 h following acute muscle stretch injury. A single stretch injury was induced to the tibialis anterior muscle of 30 male New Zealand white rabbits (n = 6 at each time point). Injured and uninjured contralateral sham-operated muscles were harvested and analyzed for NO levels, iNOS content, and iNOS activity at each time point. Furthermore, three animals were used to estimate baseline NO levels and iNOS activity. There was a progressive reduction in NO content in the injured and the sham-operated muscles up to 24 h postoperation and stretch injury (p < 0.05). At 48 h postinjury, however, NO levels were 146% higher in injured muscles than in sham-operated muscles (p < 0.05). iNOS protein content was higher at 4 h and 48 h in injured versus shamoperated muscles (p < 0.05). Similarly, iNOS activity was higher at 4 h (p < 0.05) and at 48 h (p < 0.01) in injured versus sham-operated muscles. These results suggest that NO may play an active role during the postinjury recovery of skeletal muscle modulated by iNOS expression.  相似文献   
82.
83.
1. The role of shear stress in nitric oxide (NO)-mediated attenuation of anaphylactic venoconstriction was studied using an isolated ovalbumin-sensitized guinea pig liver. 2. Guinea pigs were actively sensitized by a subcutaneous injection of 1 mg ovalbumin. Two weeks after sensitization, the livers were perfused with diluted blood under constant flow or constant perfusion pressure. The constant flow could result in increased shear stress during constriction, while the constant perfusion pressure could prevent changes in shear stress. Using the double occlusion technique to estimate the hepatic sinusoidal pressure, pre- and postsinusoidal constriction was evaluated. Hepatic anaphylaxis was induced by an injection of ovalbumin (4 microg) into the perfusate, the volume of which was 40 mL. 3. Under either constant flow or pressure, anaphylaxis caused venoconstriction of predominantly presinusoids over postsinusoids, although anaphylactic venoconstriction under constant pressure was significantly greater than that under constant flow. When shear stress was held constant by maintaining constant perfusion pressure, a NO synthase inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME, 100 micromol/L), potentiated similarly both pre- and postsinusoidal constriction induced by anaphylaxis. This suggests that hepatic anaphylaxis shear stress-independently generates NO, resulting in dilatation of both pre- and postsinusoidal vessels in a similar magnitude. In contrast, when shear stress was allowed to rise under constant flow, anaphylactic presinusoidal constriction was preferentially potentiated by L-NAME. 4. Hepatic anaphylaxis can increase NO production in a shear stress-independent manner and dilates similarly both pre- and postsinusoids, while NO produced in a shear stress-dependent manner attenuates predominantly venoconstriction of the presinusoids where shear stress is preferentially increased.  相似文献   
84.
Absorption enhancers, which increase the permeability of drugs through epithelial membranes without damaging them, are especially useful for intranasal administration of peptide drugs. In this study, aminated gelatins, candidate enhancers, having different numbers of amino groups were prepared from gelatin (H-gelatin, isoelectric point = 9.0, MW 100 kDa) and a partial gelatin hydrolysate (L-gelatin, isoelectric point = 8.0, MW 5 kDa), and the enhancing effects on the nasal absorption of insulin, used as a model peptide drug, and 5(6)-carboxyfluorescein (CF), a paracellular marker, were examined in rats. The enhancing effect on insulin and CF depends on the MW and number of amino groups. A high correlation between the enhancing effects on insulin and CF was observed and this suggests that an increase in the paracellular permeability is the mechanism governing the nasal absorption-enhancement of aminated gelatins, at least as far as insulin and CF are concerned. The enhancing mechanism might be shared with other cationic polymers having absorption-enhancing effects.  相似文献   
85.
We report a case of osteogenesis imperfecta (OI) (OMIM166210) type II, in which a prenatal diagnosis was made by three‐dimensional computed tomography (3D‐CT). Subsequent molecular analysis revealed a recurrent, heterozygous mutation in COL1A2. Fetal CT is a powerful tool for visualizing the fetal skeleton and can provide a definitive diagnosis of fetal skeletal dysplasias; however, whether or not its employment for prenatal diagnosis is warranted in terms of fetal radiation risks remains controversial, both medically and ethically. Based on our experience, we review the current state of fetal CT for the diagnosis of skeletal dysplasias, with a discussion of the relevant literature.  相似文献   
86.
Hypochondroplasia (HCH) is the mildest phenotype among fibroblast growth factor receptor 3 (FGFR3)-associated skeletal dysplasias. Affected individuals usually presents with mild short stature in preschool age. It was uncommon that a diagnosis of HCH is made in young affected children. Recently, however, prenatal ultrasound (US) has increased likelihood of detecting in utero mild short limbs. There have been a few reports on the early diagnosis of HCH in the neonatal period preceded by a suspicion of skeletal dysplasia on fetal US. However, the proper diagnosis of HCH is hampered by absence of the radiological criteria relevant to age, particularly those in the neonatal period. We report on the clinical and radiological findings in two HCH children with a FGFR3 mutation. In both children, fetal US showed short femora and relatively increased biparietal diameter (BPD). However, postnatal assessment failed to make a specific diagnosis in the neonatal period. The correct diagnosis of HCH was accomplished by reassessment after exacerbation of postnatal short stature. In retrospective radiological review, the radiological findings relevant to HCH were discernible more easily in the neonatal period than at age of 3 years.  相似文献   
87.
AIM: To determine whether absorbable sutures or non-absorbable sutures are better in preventing surgical site infection (SSI), in this paper we discuss the results of a randomized clinical trial which examined the type of sutures used during hepatectomy. METHODS: All hepatic resections performed from January 2007 to November 2008 at the Department of Surgery at Iizuka Hospital in Japan were included in this study. There were 125 patients randomly assigned to an absorbable sutures (Vicryl) group or non-absor...  相似文献   
88.
A 73-year-old man with fever, lumbago and hemosputum showed ground-glass opacity around multiple lung nodules on chest computed tomography. Examination of the man revealed anemia. Specimens obtained by video-assisted thoracic surgery revealed angiosarcoma, but the primary site of angiosarcoma could not be detected before autopsy. Angiosarcoma is a rare malignant neoplasm with rapid proliferation and they can arise at any region of the body. It can originate in the skin, soft tissue, liver or heart. Their multicentric and local recurrence easily leads us to misdiagnosis, and we have struggled to reach diagnosis and its origin. Angiosarcoma should be included in the different diagnosis of diffuse pulmonary hemorrhage with multiple lung nodules.  相似文献   
89.
OBJECTIVES: Gastric intestinal metaplasia (GIM) associated with H. pylori (HP) has been considered a premalignant lesion. However, GIM phenotype associated with HP infection and gastric cancer is unclear. The expression of COX-2 in relation to GIM phenotype is also unknown. METHODS: We evaluated cellular phenotype and COX-2 expression in the GIM from HP-positive and -negative patients from Japan in the absence of gastric cancer (n = 31) by using a colon epithelium specific monoclonal antibody (mAb Das-1) and anti-COX-2 antibody. COX-2 expression was also examined in patients with gastric cancer (n = 34), both in the cancer and in the GIM areas away from the cancer field. RESULTS: Sixty-eight percent of HP-positive GIM reacted with mAb Das-1, whereas the reactivity in the HP-negative GIM was only 25% (P < 0.001). The COX-2 expression was present in 32% of HP-positive GIM and in only 9% of HP-negative GIM (P < 0.001). In the cancer group, COX-2 expression was localized both in the cancer area (94%) and in the GIM (82%) away from the cancer. Each of the COX-2-positive tissue was also positive to mAb Das-1. CONCLUSION: HP infection is highly associated with the development of colonic-phenotype of GIM, and about half of them expressed COX-2. COX-2 expression was frequent in both gastric cancer and the GIM adjacent to the cancer. The results suggest that the presence of mAb Das-1 and COX-2 reactivity in the GIM identify the subgroup of patients who may be at risk for gastric cancer and may need close surveillance.  相似文献   
90.
BACKGROUND: Diacylglycerol (DAG) suppresses the postprandial increase in serum triglycerides, and has antiobesity effects. On the other hand, plant sterol esters (PSE) lower serum cholesterol levels in hypercholesterolemia. Thus, DAG-containing PSE (PSE/DAG) would be expected to maintain an appropriate serum cholesterol level and decrease the risk of arteriosclerotic disorders. Several recent studies, however, report negative effects of PSE on serum fat-soluble (pro)vitamin levels. The objective of this study was to investigate the effect of PSE/DAG on serum retinol, beta-carotene, and alpha-tocopherol levels using a threefold excess of the effective dose obtained in our previous study. METHODS: A randomized placebo-controlled double-blind parallel study was performed in healthy and mildly hypercholesterolemic subjects, in which the subjects ingested 1.2 g PSE/30 g DAG for 2 weeks in the form of mayonnaise-type products. Triacylglycerol (TAG) mayonnaise was used as a control. RESULT: There were no subjective adverse effects or changes in serum retinol, alpha-tocopherol, and beta-carotene levels, abdominal symptoms, hematologic values, or blood biochemical values. CONCLUSION: Ingestion of a threefold excess of PSE/DAG for 2 weeks had no adverse effects compared to ingestion of conventional TAG mayonnaise.  相似文献   
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