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51.
Two kinds of electrical stimulation, low frequency stimulation (5 Hz, 1 msec, 5 pulses, every 20 sec) and high frequency stimulation (30 Hz, 0.05-0.1 msec, 10 pulses, every 20 sec), produced contractions in the isolated guinea-pig vas deferens. These responses were blocked by tetrodotoxin but not hexamethonium. Phentolamine potentiated the contractions produced by low frequency stimulation, while it reduced the contractions produced by high frequency stimulation. Diametrically, 5-hydroxytryptamine reduced the contractions produced by low frequency stimulation, while it potentiated the contractions produced by high frequency stimulation. These inhibitory and potentiating actions of 5-hydroxytryptamine were reversed by cyproheptadine and 2-bromolysergic acid diethylamide. Moreover, that 5-hydroxytryptamine produced a depolarization of the smooth muscle membrane was shown by the sucrose gap technique. The results suggest that a 5-hydroxytryptamine receptor exists pre- and postsynaptically in the neuroeffector transmission of the guinea-pig vas deferens, that the stimulation of the presynaptic receptor by 5-hydroxytryptamine inhibits the release of a transmitter from noradrenergic nerves, and that the stimulation of the postsynaptic receptor by a high concentration of 5-hydroxytryptamine produces a depolarization of the smooth muscle membrane, and this relates to the potentiation of contractile responses.  相似文献   
52.
Cytosolic aldehyde dehydrogenase (ALDH1) variants found in alcohol flushers   总被引:1,自引:0,他引:1  
Although mitochondrial aldehyde dehydrogenase (ALDH2) has been thought to play a major role in acetaldehyde detoxification, and the high incidence of 'alcohol flushing' among Orientals is attributed to the inherited deficiency of ALDH2, the role of cytosolic aldehyde dehydrogenase (ALDH1) cannot be ignored. On the premise that alcohol flushing in Caucasians could be related to ALDH1 abnormalities, we examined the enzyme properties and electrophoretic mobilities of ALDH1 partially purified from red blood cells of nine unrelated alcohol flushers. One exhibited very low activity (10–20% of control level), and another exhibited moderately low activity (60%) and altered kinetic properties. The electrophoretic mobilities of these two samples were also distinguishable from the control samples. Immunological quantitation indicated that the amounts of ALDH1 protein in these two samples were not reduced in parallel with their enzyme deficiency. In the first case, the two characteristics, i.e. very low enzyme activity and alcohol flushing, were inherited by her daughter.  相似文献   
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To evaluate the clinical efficacy of OK-432 immunotherapy, patients admitted between 1975 and 1982 were randomized into two groups: An immunochemotherapy (IM-C) group and a chemotherapy (control) group. For each group, a fixed chemotherapy was administered using a combination of three drugs. The survival rates of cases with non-small cell carcinoma were evaluated at the end of 1987. One hundred and fifty-seven cases in the IM-C group and 148 in the control group were eligible for evaluation of long-term survival rates. Statistically significant improvement of the survival rates in the IM-G group were noted in the following items: All cases, resected cases, non-resected cases, resected stage I + II cases, resected stage III cases, completely resected cases, incompletely resected cases, and cases with epidermoid carcinoma. However, in comparison of adenocarcinoma there was no significant difference between the two groups. SU-polysaccharide skin test and natural killer activity were the best immunological parameters during the OK-432 therapy. To intensify the effects of immunotherapy, a possibility of regional immunotherapy was studied following some experimental works. Regional infusion of LAK cells (induced by incubation of patient's lymphocytes with rIL-2) through bronchial artery after regional infusion of OK-432 and chemotherapeutics showed favorable effect for advanced lung cancer. Future prospect of these regional adoptive immunotherapy was discussed.  相似文献   
55.
A 51-year-old man with recurrent gastric cancer was treated by combined administration of Cisplatin and Carmofur. The target sites were the abdominal lymph nodes and the area of invasion to the stomach. Cisplatin (50 mg/body/day) was given for 3 days, while Carmofur (400-800 mg/body/day) was administered daily in 1 course. After 1 course of administration, the target tumor was reduced in size and the therapy was continued. A complete response was confirmed by upper gastrointestinal roentgenography, endoscopy and echography after 8 courses of Cisplatin administration. The patient has survived for 2 years 6 months in a state of CR. This case suggests that a combination therapy of Cisplatin and Fluoropyrimidine derivatives might be effective for gastric cancer.  相似文献   
56.
A 65-year-old patient with ischemic heart disease and severe diabetes mellitus underwent minimally invasive direct coronary artery bypass grafting under general combined with epidural anesthesia. Paraplegia developed after surgery and the diagnosis of anterior spinal artery syndrome was made based on the patient s neurological condition and magnetic resonance imaging findings. Paraplegia following epidural anesthesia is a rare but recognized complication and this complication should be taken into account, especially in patients at risk, when considering epidural analgesia techniques in the minimally invasive cardiac surgery.  相似文献   
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A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.  相似文献   
59.
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis.  相似文献   
60.
The norA gene cloned from chromosomal DNA of a quinolone-and methicillin-resistant Staphylococcus aureus strain conferred resistance to hydrophilic quinolones such as norfloxacin, enoxacin, ofloxacin, and ciprofloxacin, but no or less resistance to hydrophobic ones such as nalidixic acid, oxolinic acid, and sparfloxacin in S. aureus and Escherichia coli. Nucleotide sequence analysis of the cloned DNA fragment revealed that the norA gene could code for a protein consisting of 388 amino acid residues with a molecular weight of 42,265, which was consistent with the experimental value of about 49,000 obtained on DNA-directed translation. The deduced NorA polypeptide has 12 hydrophobic membrane-spanning regions and is partly homologous to tetracycline resistance protein and sugar transport proteins. The uptake of a hydrophilic quinolone, enoxacin, by S. aureus harboring a plasmid carrying the norA gene was about 50% of that by the parent strain lacking the plasmid, but it increased to almost the same level as that by the latter strain with carbonyl cyanide m-chlorophenyl hydrazone. On the other hand, the uptake of a hydrophobic quinolone, sparfloxacin, was hardly affected by the norA gene. These results suggest that the NorA polypeptide may constitute a membrane-associated active efflux pump of hydrophilic quinolones.  相似文献   
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