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121.
M Ohsako Y Matsumoto 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1992,112(10):742-749
The transport properties of benzoic acid and its eighteen derivatives such as o-, m- or p-hydroxybenzoic acid (o-, m- or p-HBA), aminobenzoic acid (o-, m- or p-ABA), toluic acid (o-, m- or p-TA), fluorobenzoic acid (o-, m- or p-FBA), chlorobenzoic acid (o-, m- or p-CBA) and bromobenzoic acid (o-, m- or p-BBA) through human erythrocyte membranes were examined. The drugs having a hydrophilic ortho-substituent and those having a hydrophobic meta- or para-substituent showed higher transport. The ratio of free drugs in erythrocytes, fuR, did not relate to the partition coefficient (P). However, fuM (the ratio of free drugs in the plasma) and Kp (the ratio of partition between erythrocytes and plasma) related to the P: fuM = -0.3128 x log P + 0.9727 (R2 = 0.8722***), Kp = -0.2558 x log P + 0.8642 (R2 = 0.8413***). In p-nitrophenol-glycosides, the fuM and the Kp that were predicted from these equations were compatible with the experimental results. It was suggested from these results that the fuM and the Kp may be predictable from the P. 相似文献
122.
P J Hayden C J Welsh Y Yang W H Schaefer A J Ward J L Stevens 《Chemical research in toxicology》1992,5(2):232-237
Nephrotoxic cysteine conjugates derived from a variety of halogenated alkenes are enzymatically activated via the beta-lyase pathway to yield reactive sulfur-containing metabolites which bind covalently to cellular macromolecules. Mitochondria contain beta-lyase enzymes and are primary targets for binding and toxicity. Previously, mitochondrial protein and/or DNA have been considered as molecular targets for cysteine conjugate metabolite binding. We now report that metabolites of nephrotoxic cysteine conjugates form covalent adducts with rat kidney mitochondrial phospholipids. Rat kidney mitochondria were incubated with the 35S-labeled conjugates S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), S-(1,2-dichlorovinyl)-L-cysteine, and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine. Quantitation of metabolite binding to whole mitochondria and to mitochondrial protein and lipid fractions revealed that as much as 42% of the 35S-label associated with the mitochondria was found in the lipid fraction. Total lipids were also extracted from 35S-treated mitochondria and separated by thin-layer chromatography. 35S-Containing metabolites were found in the lipid fractions from mitochondria treated with each of the conjugates. Lipids from both [35S]CTFC- and [35S]-TFEC-treated mitochondria contained major 35S-labeled lipid adducts which had similar mobility by thin-layer chromatography. Fatty acid analysis, 19F and 31P NMR spectroscopy, and mass spectrometric analyses confirmed that the major TFEC and CTFC adducts are thioamides of phosphatidylethanolamine. 相似文献
123.
Two-color flow cytometry was carried out to determine the correlation between cell-mediated immunity and the levels of proteinuria in 30 patients with membranous nephropathy. Lymphocyte subpopulations were measured by two-color flow cytometry using various monoclonal antibodies of the Leu series. Clinically, the patients were divided into four stages as follows: 1. untreated nephrotic stage, 2. prednisolone (PSL) treated nephrotic stage, 3. persistent proteinuric stage (incomplete remission, ICR) and 4. complete remission (CR). Two-color flow cytometry showed a significant decrease in Leu 2a+15+ (suppressor T) cells and relative increase in Leu 3a+8+ (suppressor inducer T) cells in the untreated nephrotic stage. The mean Leu 3a+8-/Leu 2a+15+ (helper/suppressor) cell ratio was normalized in the persistent proteinuric stage or complete remission after treatment with PSL. Patients with membranous nephropathy showed a significant elevation of Leu 2a+DR+ cells after treatment with PSL. The abnormalities of suppressor T cells and suppressor inducer T cells in the peripheral blood appear to reflect the levels of proteinuria in patients with membranous nephropathy. It was concluded that PSL might stimulate Leu 2a positive cells and then increase the number of Leu 2a+15+ cells in the peripheral blood of patients with membranous nephropathy. 相似文献
124.
Laparoscopic cholecystectomy and time-course changes in renal function 总被引:13,自引:3,他引:10
Y. Miki K. Iwase W. Kamiike E. Taniguchi K. Sakaguchi J. Sumimura H. Matsuda I. Nagai 《Surgical endoscopy》1997,11(8):838-841
Background: Recently, the retraction method has been used to reduce intraabdominal pressure (IAP) during laparoscopic surgery. The purpose
of this study was to determine the serial changes in renal function during laparoscopic cholecystectomy (LC) using the retraction
method.
Methods: Urine output, effective renal plasma flow (ERPF), and glomerular filtration rate (GFR) were measured serially in seven patients
who underwent LC with 12 mmHg pneumoperitoneum (High-IAP group) and five who underwent LC using the retraction method with
4 mmHg pneumoperitoneum (Low-IAP group).
Results: Urine output, ERPF, and GFR were decreased during pneumoperitoneum in the High-IAP group, whereas no significant changes
in any of these parameters were observed in the Low-IAP group.
Conclusions: Our findings demonstrate that reduction of IAP to 4 mmHg using the retraction method prevents the transient renal dysfunction
caused by prolonged 12 mmHg pneumoperitoneum during LC, suggesting that the retraction method reduces the risk of perioperative
renal dysfunction during laparoscopic surgery.
Received: 26 March 1996/Accepted: 27 July 1996 相似文献
125.
Three hundred and twenty samples of subgingival plaque were obtained from 80 caucasian girls, ranging from 10 to 13 years of age. The samples were analyzed to verify the influence of age upon colonization of the gingival sulcus by microorganisms potentially pathogenic to the periodontal tissues. The gingival and plaque status were evaluated through the gingival index (GI) and plaque index (PlI) and the microflora was assessed by the enzymatic method benzoyl-arginine-naphthylamide (BANA). The results of the BANA test were positive for 62.50% of the tested individuals and 40% of the examined sites. The influence of age was statistically significant on BANA reactivity, and the number of positive sites was greater at 11 (57.5%) than at 12 years (28.8%). 相似文献
126.
D.-Y. LIN I.-S. SHEEN C.-M. CHU & Y.-F. LIAW 《Alimentary pharmacology & therapeutics》1996,10(6):961-966
Background : The clinical course of chronic hepatitis B is variable. Patients with hepatic decompensation, bridging necrosis or an alpha-fetoprotein level greater than 100 ng/mL during an exacerbation of hepatitis have a high risk of developing cirrhosis. This study was conducted to evaluate the effect of colchicine in the prevention of cirrhosis in such patients.
Methods : Patients with risk factor(s) were randomized to receive either colchicine 5 mg/week or no specific treatment, the end point being development of cirrhosis.
Results : After a follow up period of 4 years, the treatment group had a marked reduction in exacerbations of acute hepatitis (32% vs. 63%/patient/year, P <0.005). Seven out of 38 patients in the treatment group and 10 out of 27 patients in the control group developed cirrhosis. The calculated cumulative incidence of cirrhosis by the end of first, second, third and fourth years in the treatment group was 8.7, 18.6, 32 and 32%, respectively. The corresponding figures in the control group were 30, 35.5, 46.3 and 73.2%, respectively, with a P -value of 0.057.
Conclusions : The results suggest that colchicine may prevent cirrhosis in chronic hepatitis B patients with risk factor(s), possibly by suppressing exacerbations of hepatitis through an anti-inflammatory effect. 相似文献
Methods : Patients with risk factor(s) were randomized to receive either colchicine 5 mg/week or no specific treatment, the end point being development of cirrhosis.
Results : After a follow up period of 4 years, the treatment group had a marked reduction in exacerbations of acute hepatitis (32% vs. 63%/patient/year, P <0.005). Seven out of 38 patients in the treatment group and 10 out of 27 patients in the control group developed cirrhosis. The calculated cumulative incidence of cirrhosis by the end of first, second, third and fourth years in the treatment group was 8.7, 18.6, 32 and 32%, respectively. The corresponding figures in the control group were 30, 35.5, 46.3 and 73.2%, respectively, with a P -value of 0.057.
Conclusions : The results suggest that colchicine may prevent cirrhosis in chronic hepatitis B patients with risk factor(s), possibly by suppressing exacerbations of hepatitis through an anti-inflammatory effect. 相似文献
127.
A comparative study of two preservative-free tear substitutes in the management of severe dry eye 总被引:1,自引:0,他引:1
M Y Laflamme R Swieca 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》1988,23(4):174-176
Between mid-May and mid-July 1987 we performed a prospective crossover study of two unit-dose preservative-free artificial tear solutions, 1.4% polyvinyl alcohol (Refresh) and 0.1% sodium hyaluronate (Hylorin) in 14 female patients with severe dry eye syndrome. The patients were examined before treatment and after each of two trials with both products. A significant reduction in the mean score for dry-eye-induced keratitis (p = 0.001) and for mucous strands (p = 0.03) was observed following the second of two trials with sodium hyaluronate. A significant reduction in the mean score for burning and irritation was observed with both solutions (p = 0.009). We believe that the elimination of preservatives from artificial tear preparations may substantially reduce the iatrogenic effects of these frequently applied medications. 相似文献
128.
Induction of endothelium-dependent relaxation in the rat aorta by IRL 1620, a novel and selective agonist at the endothelin ETB receptor. 总被引:3,自引:2,他引:1
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H. Karaki S. A. Sudjarwo M. Hori M. Takai Y. Urade T. Okada 《British journal of pharmacology》1993,109(2):486-490
1. The effects of a novel and selective agonist at the endothelin ETB receptor, IRL 1620 (Suc-[Glu9, Ala11,15] endothelin-1 (8-21)), were examined in the isolated aorta of the rat. 2. IRL 1620 (1-300 nM) changed neither the resting tone nor the cytosolic Ca2+ level ([Ca2+]i) of the aorta without endothelium. In the presence of endothelium, however, IRL 1620 increased endothelial [Ca2+]i with little effect on the muscle tone. In the absence of external Ca2+, IRL 1620 still induced a transient increase in endothelial [Ca2+]i. 3. Noradrenaline (100 nM) increased both muscle [Ca2+]i and tension. IRL 1620 (1-300 nM) relaxed the muscle with an increase in endothelial [Ca2+]i only in the presence of endothelium. An inhibitor of nitric oxide synthase, 100 microM NG-monomethyl-L-arginine, inhibited the relaxant effect of IRL 1620 but not the increase in endothelial [Ca2+]i. 4. In resting and noradrenaline-stimulated aorta, the effects of IRL 1620 were inhibited by a selective antagonist of the ETB receptor, IRL 1038 (0.3-3 microM), although a selective antagonist of the ETA receptor, BQ-123 (3 microM), was ineffective. Verapamil (10 microM) did not alter the effects of IRL 1620. 5. A muscarinic receptor agonist, carbachol (1 microM), also induced endothelium-dependent relaxation with an increase in endothelial [Ca2+]i. However, the effects of carbachol were not inhibited by the ETB antagonist, IRL 1038 (3 microM).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
129.
Fifty-seven patients with low back pain and sciatica of various causes were reviewed with reference to problems associated with pedicle plate fixation of the lumbar spine. Eleven percent of patients had neurologic problems postoperatively and 3.5% (two patients) had severe sensory impairments. All patients had this complication in the early phases of the study. Of 297 screws, 17 broke, ie, 5.7%. These breakages occurred in 12 of 57 patients (21%). In patients with spondylolisthesis, the degree of slip correction averaged 53% postoperatively, which decreased to 35% at the 1-year follow-up. Slip angle was maintained after correction. Pedicle screw plate fixation is an effective form of immobilization of the lumbar spine used in achieving arthrodesis. The surgeon must be fully trained in methodology. It is recommended that screw and plate materials be improved to prevent screw breakage. 相似文献
130.
The binding of blood-borne estrogens in normal vegetarian and omnivorous women and the risk of breast cancer 总被引:2,自引:0,他引:2
I S Fentiman M Caleffi D Y Wang S J Hampson S A Hoare G M Clark J W Moore P Bruning J M Bonfrer 《Nutrition and cancer》1988,11(2):101-106
Serial blood samples were taken at two-hour intervals over a 24-hour period from 25 premenopausal vegetarians (12 vegans and 13 ovolactovegetarians) and from 21 omnivorous controls. All members of the former group had been on a vegetarian diet for a minimum of three years. The mean proportion of estradiol unbound to blood proteins was similar in both vegetarians (1.26%) and meat eaters (1.16%). However, the amount bound to albumin was significantly raised in vegetarians (50.1% vs. 43.1%, p less than 0.009), whereas that bound to sex hormone-binding globulin (SHBG) was correspondingly lower (48.7% vs. 55.8%, p = 0.01). Mean levels of SHBG were similar in vegetarians (59.9 nmole/l) and omnivores (62.0 nmole/l), as was the total amount of free fatty acid (0.42 mmole/l for both). Within the vegetarian group, no differences were detected between vegans and ovolactovegetarians. 相似文献