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71.
The structures of rhodopeptins, novel antifungal peptides, were determined on the basis of physico-chemical analyses of the intact molecules and their acid hydrolysates. The structures of rhodopeptins C1, C2, C3, C4 and B5 were determined to be cyclo (-Gly-L-Orn-L-Val-3-amino-10-methyldodecanoyl-), cyclo (-Gly-L-Orn-L-Ile-3-amino-10-methyldodecanoyl-), cyclo (-Gly-L-Orn-L-Val-3-amino-12-methyltridecanoyl-), cyclo (-Gly-L-Orn-L-Val-3-amino- 12-methyltetradecanoyl-) and cyclo (-Gly-L-Lys-L-Val-3-amino-13-methyltetradecanoyl-), respectively. They are novel cyclic tetrapeptides containing a lipophilic beta-amino acid. 相似文献
72.
J H Lin M Chiba I W Chen J A Nishime F A deLuna M Yamazaki Y J Lin 《Drug metabolism and disposition》1999,27(10):1187-1193
Indinavir, a potent and specific inhibitor of HIV protease, is a known substrate of cytochrome P-450 (CYP) 3A and p-glycoprotein. The purpose of this study is to investigate and compare the inducing effect of dexamethasone (DEX) on CYP3A and p-glycoprotein in the hepatic and intestinal first-pass metabolism of indinavir in rats. Pretreatment of rats with DEX had little effect on the pharmacokinetics (Cl and T(1/2)) after i.v. administration of indinavir, whereas DEX markedly altered the peak concentration (C(max)) and bioavailability of indinavir after oral dosing. The C(max) decreased from 2.8 microM in control rats to 0.28 microM in DEX-treated rats, and bioavailability decreased from 28 to 12.4%. The decreased bioavailability after DEX pretreatment was due mainly to an increase in first-pass metabolism. Intestinal first-pass metabolism (E(G)) increased from 6% in control rats to 34% in DEX-treated rats, and hepatic first-pass metabolism (E(H)) increased from 65 to 82%. Analysis of in vitro kinetic data revealed that the increased intestinal and hepatic metabolism by DEX was attributed to an increase in the V(max), as a result of CYP3A induction, without a significant change in the K(m) values. DEX pretreatment also induced p-glycoprotein in the intestine and liver of rats. p-Glycoprotein appeared to increase the intestinal metabolism of indinavir whereas it had little effect on the hepatic metabolism of indinavir. Although it has been suggested that the role of intestinal metabolism for some drugs is quantitatively greater than that of hepatic metabolism in the overall first-pass metabolism, the contribution of intestinal metabolism to the overall first-pass metabolism of indinavir in rats is not quantitatively as important as the hepatic metabolism, regardless of DEX induction. 相似文献
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76.
Video-assisted Thoracoscopic Lobectomy Achieves a Satisfactory Long-term Prognosis in Patients with Clinical Stage IA Lung Cancer 总被引:5,自引:0,他引:5
We designed a prospective trial to determine the long-term prognosis of video-assisted thoracoscopic (VATS) lobectomy versus
conventional lobectomy for patients with clinical stage IA (T1N0M0) lung cancer. Between January 1993 and June 1994, 100 consecutive
patients with clinical stage IA non-small cell lung carcinoma underwent either conventional lobectomy through an open thoracotomy
(open group; n= 52) or VATS lobectomy (VATS group; n= 48). Lymph node dissections were performed in a similar manner in both groups. No significant differences were observed
in the number of dissected lymph nodes between the 2 groups. Pathologic N1 and N2 disease was found in 3 and 1 patients, respectively,
from the open group, and in 2 and 1 patients, respectively, from the VATS group. During the follow-up period, distant metastases
and local or regional recurrences developed in 7 and 3 of the open group patients, respectively, and in 2 and 3 of the VATS
group patients, respectively. Two and one of the open and VATS group patients developed second primary cancers, respectively.
The overall survival rates 5 years after surgery were 85% and 90% in the open and VATS groups, respectively (log-rank test,
p= 0.74; generalized Wilcoxon test, p= 0.91). VATS lobectomy with lymph node dissection achieved an excellent 5-year survival, similar to that achieved by the
conventional approach. 相似文献
77.
K Kaneko M Chiba M Hashizume O Kunii S Sasaki T Shimoda Y Yamashiro W Caypil D Dauletbaev 《Archives of disease in childhood》2003,88(11):966-968
BACKGROUND: The Aral Sea region is a natural area seriously polluted by human activities. Recent surveillance revealed the increased prevalence of diverse chronic diseases in children. AIMS: To investigate the function of renal tubules, which are most at risk of damage as a result of heavy metal intoxication, in children of the Aral Sea region. METHODS: A group of 205 children living in Kazalinsk, close to the Aral Sea, and a group of 187 children living in Zhanakorgan, far from the Aral Sea, were examined by means of random urine samples. Both urinary N-acetyl-beta-D-glucosaminidase (NAG; U/mmol Cr) and beta2 microglobulin (BMG; microg/mmol Cr) were calculated for each subject. RESULTS: Mean urinary NAG and BMG were both significantly higher in Kazalinsk than in Zhanakorgan (NAG: 0.77 (0.58) and 0.62 (0.37) U/mmol Cr; BMG: 41.8 (54.8) and 22.5 (20.4) microg/mmol Cr, respectively; mean (SD), p < 0.01). The number of children with abnormal values of NAG (>1.5 U/mmol Cr) was significantly more prevalent in Kazalinsk than in Zhanakorgan (7.9% and 2.6%, respectively, p < 0.05). CONCLUSION: Renal tubular function of children around the Aral Sea region is profoundly impaired. This should be taken into account when considering the health problems of this area. 相似文献
78.
Yusuke Demizu Kazufumi Kagawa Yasuo Ejima Hideki Nishimura Ryohei Sasaki Toshinori Soejima Toshihiro Yanou Masakazu Shimizu Yoshiya Furusawa Yoshio Hishikawa Kazuro Sugimura 《Radiotherapy and oncology》2004,71(2):207-211
We investigated the biological effect of combining carbon-beam and X-ray in vitro. The results showed that when we employed Gray equivalent as the indication of therapeutic dose, the effects could be explained with simple additive way in the treatment plan. This fact provides important information about the combined therapy of carbon-beam and X-ray. 相似文献
79.
Hideshi Tomita Shigeto Fuse Kazuo Ikeda Kazuko Matsuda Shunzo Chiba 《Pediatrics international》1998,40(6):608-611
We report a 3-month-old girl with Costelio syndrome complicating fatal hypertrophic obstructive cardio-myopathy. She had typical findings of this syndrome, slight dyspnea and persistent wheezing. Doppler echocardiography revealed asymmetric septal hypertrophy and systolic anterior movement of the anterior mitral leaflet. There was grade 1 mitral regurgitation. Although once her heart failure had been controlled medically, she died suddenly following deterioration of her heart condition. Costelio syndrome can complicate fatal hypertrophic obstructive cardiomyopathy. 相似文献
80.
A 74-year-old woman underwent total cystectomy with ureterostomy on March 1993 on a diagnosis of advanced bladder cancer. The pathological diagnosis was transitional carcinoma grade 3, pT3a pN0 pV1, pL2. Two courses of adjuvant chemotherapy with CDDP and MTX were added. Three years and 3 months later, she began to suffer from amnesia and hemiparalysis on her left side. Brain MRI examination revealed a solid tumor, 4 x 4 x 3 cm in size, in the right frontal lobe of the cerebrum. No other metastatic lesions were found. She underwent surgical resection of the tumor and subsequent irradiation to right frontal lobe in the cerebrum. Pathological examination confirmed its origin of bladder cancer. She has been enjoying a disease-free life for 3 years with minimal neurological symptoms. 相似文献