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1.
Four enantiomers (3a-d) of the title compound, YM-09730 (3), were synthesized by the reaction of (-)- or (+)-5-(methoxycarbonyl)-2, 6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid (1a or 1b) with (S)- or (R)-1-benzyl-3-pyrrolidinol (2a or 2b). [3H]Nitrendipine binding affinity and coronary vasodilating activity of these compounds were evaluated. The absolute configuration of the most potent enantiomer (3a) with the longest duration was unequivocally determined to be (S)-1,4-dihydropyridine-C4 and (S)-pyrrolidine-C3 (S,S) by X-ray crystallographic study on 3a X HBr as well as 3a X HCl. The configuration of 1a corresponds to R, and the other enantiomers of 3 were respectively determined by chemical correlation. The potency order of the four enantiomers was (S,S)-3a greater than (S,R)-3b greater than (R,R)-3d greater than (R,S)-3c. Latent chiral characters of nifedipine derivatives with the identical ester groups were assigned by comparison of their puckering modes of 1,4-dihydropyridine (DHP) rings with those found in 3a X HCl or 3a X HBr. On the basis of the assignment, it has been revealed that the (S)-DHP nifedipine derivatives possess the synperiplanar carbonyl group at C5. The conformational restriction may be a factor causing stereoselectivity of antagonism.  相似文献   
2.
Background: Recent evidence suggested that propofol can deteriorate the cerebral oxygen balance compared with inhalational anesthetics. However, dose-related influences of propofol on cerebral oxygen balances were not clearly investigated. In the current study, the authors investigated the effects of increasing concentrations of propofol on jugular venous bulb oxygen saturation (Sjo2) in neurosurgical patients under normothermic and mildly hypothermic conditions.

Methods: After institutional approval and informed consent were obtained, 30 adult patients undergoing elective craniotomy were studied. Patients were randomly allocated to either normothermic or hypothermic group (n = 15 in each group). In the normothermic and hypothermic groups, tympanic membrane temperature was maintained at 36.5[degrees] and 34.5[degrees]C, respectively. Sjo2 was measured at predicted propofol concentrations of 3, 5, and 7 [mu]g/ml using a target-controlled infusion system in both groups.

Results: At a predicted propofol concentration of 3 [mu]g/ml, there were no significant differences in Sjo2 values between the normothermic and hypothermic groups, although the incidence of desaturation (Sjo2 < 50%) was significantly higher in the normothermic group than in the hypothermic group (30% vs. 13%; P < 0.05). Sjo2 values and the incidence of desaturation remained unchanged during the changes in predicted propofol concentration from 3 to 7 [mu]g/ml both in the normothermic and hypothermic groups.  相似文献   

3.
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC.  相似文献   
4.
The case of a 53-year-old man with hematospermia and massive postejaculation hematuria that caused urinary retention is described. This is the sixth case in the English and Japanese language literature. Cystourethroscopic examination revealed that a solitary raised tumor was present just distal to the vermontanum, and that bleeding was from its apex. Histologic examination of an excisional biopsy sample showed features compatible with hemangioma.  相似文献   
5.
Background :
The aim of this study was to investigate the influence of osteoarthritis of lumbar vertebrae on serum bone formation and resorption marker levels of patients with benign prostatic hypertrophy (BPH).
Methods :
Serum levels of carboxyterminal propeptide of type I procollagen (PICP), alkaline phosphatase (ALP), carboxyterminaltelopeptide of type I collagen (ICTP), and prostate-specific antigen (PSA) were examined in 40 patients with BPH, and the presence of osteoarthritis at the lumbar vertebrae of the patients was evaluated by plain x-ray-p.
Results :
Findings of osteoarthritis were observed in 23 of the 40 patients (58%), and 10 of the patients had severe osteoarthritis (involving at least 2 lumbar vertebral bodies). The serum levels of PICP, ALP, ICTP, and PSA of the patients without osteoarthritis findings were not different from those of the patients with osteoarthritis or severe osteoarthritis.
Conclusion :
The influence of osteoarthritis on serum bone formation and resorption marker levels of patients with BPH appears to be rather slight, if there is any influence at all.  相似文献   
6.
Thoracic outlet syndrome is a disorder caused by neurovascular compression of the brachial nerve plexus and the subclavian artery or vein by bones and muscles. We report the MR angiographic findings of a patient with thoracic outlet syndrome.  相似文献   
7.
To examine the role of the apoptosis of macrophages and smooth muscle cells in the development of atherosclerosis, human aortic tissues with intimal lesions were immunostained with antibodies against terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL), single-stranded DNA (clone F7-26), and active caspase-3. Apoptotic cells were detected in the intima using both TUNEL and single-stranded DNA, however, the latter method was the more sensitive one for detecting apoptotic cells in the early stages of atherosclerosis. The number of apoptotic cells increased as the disease progressed. It implies that the apoptosis of intimal cells is involved in the formation of atherosclerotic lesions. In addition, quantitative analyses of the cell types undergoing apoptosis using double-immunostaining revealed that the susceptibility of macrophages and smooth muscle cells to apoptosis was greater specifically in atheroma than in the other atherosclerotic lesions, and macrophages were more susceptible to apoptosis than smooth muscle cells. The frequency and spatial distribution of oxidized low-density lipoprotein (oxLDL) (FOH1a/DLH3)-positive cells were examined by immunohistochemistry, and the results resembled those of apoptotic cells. The number of oxLDL-positive cells in the intima significantly correlated with the susceptibility of smooth muscle cells, but not with that of macrophages, to apoptosis. These results suggest that oxLDL affects the apoptosis of smooth muscle cells during the atherosclerotic development.  相似文献   
8.
In primary care, the management of stress-related diseases occupies a wide spectrum of prevention and treatment, from holistic health care to final cure, centered on medical health and an organic integration of body, mind, and social parameters. Inquiries are being made at examinations and interviews to obtain information on the health condition of the patient, but, they are inadequate. There is a need for an objective indicator to help in the diagnosis. With the introduction of the Stress Barometer (measurements of 17-ketosteroid sulfates and 17-hydroxy-corticosteroids) it has become possible to obtain critical information on a patient in a very short time. This method allows early detection of stress, depression state and tiredness from work which is not presently possible from blood tests. It then becomes possible to call the patient's attention to these matters and to work at increasing awareness, energy levels, and responses to the conditions that are determined in this manner.  相似文献   
9.
In order to establish an animal model of pulmonary vasoconstriction we followed the time course of intrapulmonary shunt (Qs/Qt) in a canine model of lobar atelectasis with closed chest. Ten mongrel dogs were studied. Bronchial occlusion of the right lower lobe (RLL) was performed by inflating the balloon of a Foley catheter placed through a rigid bronchoscopy. Analysis of variance was used for statistical analysis. (15 minutes) After occlusion Qs/Qt reached its maximum increasing from 8.2 +/- 3.6 to 29.7 +/- 11.7% (p less than 0.05) and PaO2 decreased from 357 +/- 49 to 100 +/- 43 mm Hg (p less than 0.05). Afterwards, there was a progressive decline of Qs/QT accompanied by an also progressive increase in PaO2. At the end of the experiment (3 hrs post atelectasis) Qs/Qt was 11.2 +/- 4.9 and PaO2 251 +/- 124 mm Hg (p less than 0.05). Pulmonary vascular resistance increased post atelectasis from 439 +/- 168 to 598 +/- 256 d.s.cm-5 (p less than 0.05). Complete atelectasis of the RLL was confirmed postmortem. As the changes in Qs/Qt and PaO2 did not parallel the change in cardiac output we conclude that the mechanism of decrease in Qs/Qt was hypoxic vasoconstriction.  相似文献   
10.
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo.  相似文献   
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