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91.
Overnight fasting causes hemorrhagic lesions in the stomach of streptozotocin (STZ)-induced diabetic rats, but the pathogenetic mechanism remains unknown. The present study was performed to investigate the pathogenesis of such lesions developed in STZ-diabetic rats after starvation, mainly in relation to blood glucose changes. A single injection of STZ (70 mg/kg, intraperitoneally) induced hyperglycemic conditions one week after the administration, and high blood glucose levels (BGL: >350 mg%) remained up to three weeks later. The STZ-diabetic rats developed gastric lesions with the marked reduction of BGL after 18 hr of fasting, depending upon the duration of diabetes; the lesion score and BGL reduction in the 3-week-old STZ rats were 32.0±7.8 mm and >250 mg/100 ml, respectively. Acid secretion in the pylorus-ligated rats was not significantly changed in the STZ-induced diabetic conditions for the initial two weeks but slightly decreased at three weeks when compared with normal rats. Fasting of normal rats for 18 hr did not cause either BGL reduction or any lesion in the stomach. In the 3-week-old STZ animals, the severity of gastric lesions increased with the duration of fasting (4–18 hr) and was again closely associated with the degree of BGL reduction. These lesions induced by 18 hr of starvation in 3-week-old STZ rats were significantly inhibited by pretreatment with insulin (4 units/rat/day) for the last one week to maintain BGL within normal ranges or by intravenous infusion of 25% glucose during fasting period. Both of these treatments significantly prevented BGL reduction in response to fasting. These results suggest that gastric lesions induced in STZ-diabetic rats by fasting are insulin-sensitive and may be associated with a profound hypoglycemic response to food deprivation.  相似文献   
92.
Multiple studies comparing sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with coronary artery disease have been performed. Despite these comparisons, it remains uncertain whether a differential in long-term efficacy and safety exists. Unselected patients treated exclusively with 1 drug-eluting stent type were enrolled in the Registry Experience at the Washington Hospital Center with Drug-Eluting Stents. There were 2,099 patients (3,766 lesions) treated with SES and 1,079 patients (1,850 lesions) treated with PES. Patients were followed at 30 days, 1 year, and 2 years for the clinical endpoints of death, myocardial infarction, target vessel revascularization, and definite and definite/probable stent thrombosis. Patients in the SES group had more dyslipidemia, history of congestive heart failure, and ostial lesions; patients treated with PES had more previous coronary artery bypass surgery, unstable angina, and type C lesions. At 2 years, unadjusted major adverse cardiac events (MACE) (22.6% vs 21.1%, p = 0.3) and target vessel revascularization (13.3% vs 11.2%, p = 0.1) were comparable. The incidence of definite stent thrombosis was higher in the SES group (1.8% vs 0.9%, p = 0.05) driven by early events. Similar results were seen after adjustment for baseline differences: MACE (hazard ratio 1.1, 95% confidence interval [CI] 0.9 to 1.3, p = 0.5), definite stent thrombosis (hazard ratio 2.3, 95% CI 1.0 to 5.2, p = 0.05), and target vessel revascularization (hazard ratio 1.1, 95% CI 0.9 to 1.4, p = 0.4). The incidence and rate of late stent thrombosis (>30 days) were similar (0.7% vs 0.5%, p = 0.4 and 0.24%/year, both groups, respectively). In conclusion, no major differential in long-term safety or efficacy was detected between SES and PES; both stent types were efficacious in reducing revascularization but were limited by a small continual increase in late stent thrombosis.  相似文献   
93.
For patients undergoing elective percutaneous coronary intervention (PCI), procedural anticoagulation with bivalirudin was previously shown to significantly reduce bleeding complications at the cost of a modest increase in ischemic events compared with unfractionated heparin (UFH) and glycoprotein IIb/IIIa inhibitors (GPIs). However, the excess bleeding in patients treated with UFH and GPIs may have been caused by excessively high UFH doses and increased activated clotting times. This study sought to determine the bleeding risk of targeted low-dose UFH with GPIs compared with bivalirudin in patients undergoing elective PCI. Of 1,205 patients undergoing elective PCI, 602 underwent PCI with adjunctive UFH and GPIs with the UFH dose targeted to an activated clotting time of approximately 250 seconds, and 603 patients matched for baseline characteristics underwent PCI with bivalirudin. Outcomes were analyzed for major bleeding (hematocrit decrease >15%, gastrointestinal bleed, or major hematoma) and 6-month major adverse cardiac events (death, myocardial infarction, and target-lesion revascularization). The maximum activated clotting time achieved was 261.7 +/- 61.6 seconds in the UFH/GPI group and 355.4 +/- 66.6 in the bivalirudin group (p <0.001). In-hospital major bleeding rates were similar between groups (1.8% UFH/GPI vs 1.7% bivalirudin; p = 0.83), as were transfusion requirements (1.2% UFH/GPI vs 0.5% bivalirudin; p = 0.61). The 6-month major adverse cardiac event rate was also similar between groups (9.5% UFH/GPI vs 9.0% bivalirudin; p = 0.81). In conclusion, there were no significant differences in major bleeding and 6-month major adverse cardiac events for patients undergoing elective PCI treated with targeted low-dose UFH and GPIs compared with those treated with bivalirudin.  相似文献   
94.
95.
A case of familial spinocerebellar ataxia 6 with typical symptoms is presented. A 60-year-old Japanese female suffered from gait disturbance, ataxia and dizziness. Head magnetic resonance imaging revealed a typical atrophic image in cerebellum. Genetic tests revealed an expanded allele of 22 CAG repeats at the spinocerebellar ataxia type 6 locus. She was diagnosed with spinocerebellar ataxia 6. Her mother was also diagnosed with the same disease. A mixture of 18 medicinal herbs (modified Zhengan Xifeng Tang) was given according to the differential diagnosis based on the guidelines of traditional Chinese medicine. All of the symptoms were remarkably improved after 60 days of the herbal treatment. One year after discontinuation of the treatment, she complained of gait ataxia. She was treated with the modified Zhengan Xifeng Tang for 60 days. Gait ataxia was markedly improved by the second treatment. Fifteen months after discontinuation of the second treatment, she complained of gait ataxia again. The same remedy was given for 60 days. Gait ataxia was remarkably reduced again. The results may imply therapeutic potential of the medicinal herbs for spinocerebellar ataxia 6.  相似文献   
96.
Neuronal cell death accounts for the clinical manifestations in Alzheimer's disease (AD). To establish the curative therapy of AD, neuroprotection is one of the primary therapeutic targets, and the elucidation of the mechanism of neuronal cell death is mandatory. Detailed characterization of neuronal cell death caused by familial AD (FAD)-linked mutant genes revealed that different cell death pathways are evoked by different types of mutants. Humanin (HN), a newly identified neuroprotective peptide, suppresses neuronal cell death caused by all known FAD mutants and A beta, while it has no effect on neuronal cell death caused by AD-irrelevant insults. The functional target of HN is the antagonism to neuronal death, not the modulation of A beta production, suggesting that HN-based medication can be combined with other remedies targeting A beta. HN is a promising seed for a novel therapy aiming at complete cure of AD through the suppression of neuronal loss.  相似文献   
97.
98.
Granulocyte elastase released from activatedleukocytes plays an important role in leukocyteinfiltration. Since activated leukocytes have been shownto be involved in the pathogenesis of gastric mucosal lesion formation induced by nonsteroidalantiinflammatory drugs, inhibition of granulocyteelastase release from activated leukocytes may be usefulin the prevention of these lesions. Rebamipide, a novel antiulcer agent, inhibited granulocyte elastaserelease from activated neutrophils in vitro. Rebamipideand ONO-5046, a granulocyte elastase inhibitor, markedlyinhibited gastric mucosal lesion formation in rats. Gastric myeloperoxidase activity wassignificantly increased 3 hr after indomethacinadministration. This increase was significantlyinhibited by rebamipide and ONO-5046. Cimetidine did notinhibit granulocyte elastase release from activatedneutrophils. Although cimetidine markedly prevented theindomethacin-induced gastric mucosal lesion formation,it did not reduce the gastric myeloperoxidase activity. Therefore, unlike cimetidine, rebamipide mayprevent indomethacin-induced gastric mucosal lesionformation by inhibiting neutrophil activation.  相似文献   
99.
Typical angioid streaks were found on routine ophthalmologic examination in a 42-year-old female with yellowish, coalescing papules on her neck without any symptoms. Biopsy of the cutaneous lesion showed degeneration and fragmentation of the elastic fibers and many basophilic-stained calcifications in mid-dermis, which are consistent with pseudoxanthoma elasticum. Twenty-four-hour Holter electrocardiography (ECG) showed sinus arrest for 2.5 seconds, and an electrophysiological study revealed sinus nodal dysfunction (sick sinus syndrome), whereas all of the coronary arteries were intact, despite a treadmill stress ECG test showing significant ST depressions. The association of pseudoxanthoma elasticum and sick sinus syndrome is very rare. One possible explanation for this association here is that the degeneration of elastic fiber in endomysium of the sino-atrial node may have affected heart conduction systems, resulting in sick sinus syndrome.Part of this work was presented at the 76th Japanese Circulation Society Kyushu Meeting, Japan, June 18, 1994  相似文献   
100.
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