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71.
Local suppressive effect of clonidine on penile erection in the dog   总被引:1,自引:0,他引:1  
Dogs, 8.5 to 10 kg. in weight, were anesthetized with sodium pentobarbital (35 mg./kg.), intraperitoneally. Penile erection as indicated by an increase in the intracorporal pressure (ICP-increase) was produced by electrical stimulation of the right cavernous nerves. Drugs were administered into the internal pudendal artery (IPA) and femoral vein. A low dose (0.2 to 0.4 microgram/kg.) of clonidine, an alpha 2 adrenoceptor agonist, which could not affect either ICP or systemic arterial pressure (SAP) through an intravenous route, did suppress the ICP-increase markedly via direct injection into the IPA which supplies the penile blood flow. By intra-IPA injection, yohimbine (2.5 micrograms/kg.), an alpha 2 adrenoceptor antagonist, remarkably restored the ICP to the erection state. By intravenous injection, clonidine at a dose of 1.6 to 3.2 micrograms/kg. also profoundly reduced the ICP-increase, but only negligibly lowered the SAP. The IPA blood flow (IPAF) decreased coincidentally when the ICP-increase was effectively reduced by either intravenous or intra-IPA injection of clonidine. These findings suggest clonidine could act locally in the penile structure to suppress penile erection, possibly resulting from a penile vasoconstriction involving alpha 2 adrenoceptor. Whether this vasoconstriction is caused by a direct alpha 2 stimulating effect on the vascular smooth muscle or by an alpha 2 presynaptic inhibition of the vasodilator nerve (cavernous nerve) endings has been discussed.  相似文献   
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Several studies have reported the therapeutic use of caffeoylquinic acid (CQA) derivatives in the management of hyperglycemia. This study used a simulated in vitro gastrointestinal digestion model to assess the inhibitory effects of CQA derivatives-rich sweet potato leaf extract (SPLE) and a commercially produced green coffee bean extract (GCBE), each with total polyphenols contents of 452 mg g−1 and 278 mg g−1, respectively, against starch digestion. The changes in the amounts of total polyphenols and total CQA derivatives during in vitro gastrointestinal digestion were also examined. The results indicated that both extracts contained substantial levels of CQA derivatives (136 mg g−1 and 83.5 mg g−1 of extract for SPLE and GCBE, respectively). The amounts of total polyphenols and total CQA derivatives in 20 mg of SPLE and GCBE samples decreased from 9.04 mg to 0.58 mg and from 5.56 mg to 0.58 mg, and from 2.72 mg to 0.16 mg and from 1.67 mg to 0.10 mg, respectively, following in vitro gastrointestinal digestion and subsequent dialysis. When SPLE and GCBE were accompanied with starch for in vitro digestion test, they both exhibited inhibitory effect against starch digestion during simulated intestinal digestion, with estimated half maximal inhibitory concentration (IC50) values of 4.91 mg and 6.06 mg polyphenols, respectively. The amount of glucose permeated through dialysis membrane also decreased significantly in comparison with the extract-negative control. Thus, both SPLE and GCBE were capable of modulating the release of glucose from starch digestion in simulated intestinal tract. The observed inhibitory effects against glucose release were presumably due in part to the presence of CQA derivatives in the tested extracts. The SPLE had higher inhibitory effect against in vitro starch digestion than the commercially prepared reference GCBE. Therefore, the SPLE might be used to manage hyperglycemia over the long term.  相似文献   
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Oral cancer is one of the leading causes of cancer death, which are mostly preceded by oral potentially malignant disorders (OPMDs). Taiwanese government launched a free oral cancer screening program. The aim of this study was to analyze the malignant transformation rate of OPMDs.This study was based on national-wide oral screening databases. 3,362,232 people were enrolled. Patients clinically diagnosed with leukoplakia, erythroplakia, oral submucosal fibrosis (OSF), oral verrucous hyperplasia (OVH), and oral lichen planus (OLP), from 2010 to 2013, were identified. We followed up OPMD patients in cancer registry databases to analyze the malignant transformation rate.The malignant transformation rates from the highest to the lowest were: OVH > OSF > erythroplakia > OLP > leukoplakia. The malignant transformation rate was 24.55, 12.76, 9.75, 4.23, and 0.60 per 1000 person-years in the OVH, OSF, erythroplakia, leukoplakia, and comparison cohort. The hazard ratio was 8.19 times higher in the OPMD group compared with comparison cohort group, after age and habit adjustment. Female patients with OPMDs had a high risk of malignant transformation.Nationwide screening is very important for early diagnosis. OVH had the highest malignant transformation possibility. Female OPMD patients are a rare but have a relatively high malignant transformation rate.  相似文献   
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Intravenous picrotoxin injection has been established as a model of producing arrhythmias, mainly through enhanced central sympathetic outflow. The effects of calcium-channel blockers, and a beta-blocker on these arrhythmias were tested in chloralose-anesthetized cats. Picrotoxin (10 mg/kg, i.v.) produced mostly ventricular, sometimes supraventricular tachycardias and ectopic beats, as well as a marked elevation of arterial blood pressure. Nifedipine at the doses of 2 micrograms/kg (i.v. or i.c.) and 5 micrograms/kg (i.v.) transiently suppressed the arrhythmias in some of the cats tested. With the dose of 10 micrograms/kg (i.v.), it promptly and consistently abolished the arrhythmias without recurrence and significantly reduced the blood pressure (-62 +/- 8/-59 +/- 8 mmHg, delta systolic pressure/delta diastolic pressure, p less than 0.001, n = 9). A similar degree of blood pressure reduction (-69 +/- 8/-67 +/- 7 mmHg, n = 6) after sodium nitroprusside (4-5 mg/kg, i.v.) injection abolished the arrhythmias in 4 of 6 cats; however, there was marked ECG evidence of myocardial ischemia in 3 cats. Verapamil (50 micrograms/kg, i.v.) transiently abolished the arrhythmias and significantly decreased the blood pressure (7/7 cats), whereas a larger dose (150 micrograms/kg) had a persistent effect (2/4 cats). Propranolol at a dose of 240 micrograms/kg also consistently abolished the arrhythmias without recurrence in all 4 cats. We conclude that nifedipine, verapamil and propranolol are effective in the treatment of picrotoxin-induced arrhythmias. This result indicates that calcium-channel blockers or beta-blockers may be clinically effective in the treatment or prevention of arrhythmias caused by intracranial lesions with enhanced sympathetic outflow.  相似文献   
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Chu  Yu-Ju  Jeng  Wen-Juei  Pan  Mei-Hung  Hu  Hui-Han  Luo  Wen-Sheng  Su  Chien-Yu  Chiang  Chen-Tse  Jen  Chin-Lan  Chen  Chien-Jen  Yang  Hwai-I 《Journal of gastroenterology》2022,57(6):423-432
Journal of Gastroenterology - In chronic hepatitis B virus (HBV) infection, earlier seroclearance of hepatitis B e antigen (HBeAg) is associated with more favorable outcomes. Soluble programmed...  相似文献   
80.
To further clarify the association of HLA DR alleles with type 1 diabetes mellitus and the influence of age-onset and gender on type 1 diabetes, we investigated HLA-DR in 76 child onset Chinese (36 males) type 1 diabetes patients and 154 normal controls by using PCR-SSP (sequence specific primer). The mean age of onset of diabetes patients was 8.43 +/- 3.96 year-old. Our results revealed that the frequencies of DR3, DR4 and DR9 in diabetes patients were significantly higher than those in control group (all P < 0.01). The susceptible alleles were DR3, DR4, DR9, with relative risks of 8.25, 2.57 and 2.67, respectively. The protective alleles to type 1 diabetes were DR 2, DR8, DR11 and DR12 with relative risk of 0.24, 0.15, 0.16 and 0.39, respectively. There were no significant differences between the frequencies of HLA DR 3, DR4, DR9, DR3/4, DR3/9 and DR4/9 in male and female diabetic children. We divided the diabetes patients into three groups according to their age of onset (1-5 years old, 6-10 years old and 11-17 years old). There was a trend that the frequencies of DR9 decreased with the increase of age at onset, but there was no significant difference of DR3, DR4, DR9, DR3/4, DR3/9 and DR4/9 frequencies between diabetes children with age onset 0-10 years and 11-17 years. As to the influence of gender on the HLA genotypes, the frequency of DR3/4 decreased with the increase of age at onset for male patients and the frequency of DR3/4 increased with the increase of age at onset for female patients.  相似文献   
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