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31.
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively, throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing. The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively, in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum. The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed from the circulation to the brain with low penetrability. Received: 30 October 1996/Final version: 16 December 1996  相似文献   
32.
Epidural spinal cord stimulation was carried out in 4 patients with denervation caused by spinal cord lesion, and we reviewed previously reported cases. Initial result showed at 1 week in 100% of our cases, but about 1/3 of the cases, even those with the same denervation caused by spinal cord lesion, had no pain relief at this stage in previously reported cases. In our cases, excellent pain relief was gained temporarily, even though the painful area and the spinal cord lesion were separated somatotopically in 2 cases (case 3, 4). Temporary success bore no relationship to quality and duration of pain. In all cases except case 1, a rapidly decreasing effectiveness was noted, and finally no pain relief was gained at all after 4, 3 and 5 months, respectively. In case 1 there was persistent pain relief estimated at 70-80% after 19 months, only when the spinal cord was stimulated. Epidural stimulation also produced sensations in the painful area. Spinal cord stimulation would suppress at least the dorsal horn neurons which were destroyed by various kinds of diseases. A decline in effectiveness with time would occur due to essential causes of the deafferentation pain, such as anatomical and regeneration factors.  相似文献   
33.
M Abe  K Tasaki  K Tominaga  S Fukuhara  S Imai  T Osato  H Wakasa 《Cancer》1992,69(3):763-771
Two human Burkitt's lymphoma cell lines (HBL-4 and HBL-5) were established individually from two patients with small noncleaved cell lymphoma (Burkitt's type). The HBL-4 cell line is Epstein-Barr virus (EBV)-negative, and the HBL-5 cell line is EBV-positive. Cytogenetically, both cell lines had the same chromosomal translocation, t(8;14)(q24;q32) as those observed in the primary malignant cells from individual patients. Morphologic, immunophenotypic, cytogenetic, and molecular studies confirmed that both cell lines were derived from the primary lymphoma cells in vivo. HBL-4 cells lacked CD23(H107), CD11a(LFA-1), and latent membrane protein (LMP) but expressed CD54(ICAM-1) at low levels, whereas HBL-5 cells showed the high level of expression of CD54 and faint expression of LMP but lacked CD11a. In addition, the EBV-positive lymphoblastoid cell line (LCL) expressed CD11a, CD23, CD54, and LMP at high levels. Therefore, an HBL-5 phenotype with expression of CD54 and LMP tends toward an LCL phenotype, and the augmentation of CD54 on the HBL-5 cells in comparison with primary lymphoma cells is likely to be upregulated by LMP, probably resulting from the EBV infection. There was little difference in the BrdUrd uptake in vivo and in vitro, doubling time, tumorigenicity, and dynamics of tumor growth in athymic nude mice between both cell lines. These findings indicate that the potentiality of cell growth and tumorigenicity of these two cell lines are unlikely to be related with EBV.  相似文献   
34.
Aortic arch replacement with proximal first technique.   总被引:2,自引:0,他引:2  
BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.  相似文献   
35.
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.  相似文献   
36.
Thallium lung uptake (TL-uptake) was usually treated as background for myocardial image and increase of TL-uptake in exercise test was considered as marker of depressed cardiac function. It was reported that marked increase of TL-uptake in patients with acute myocardial infarction (AMI) corresponded to acute severe congestive heart failure. Here effect of TL-uptake on myocardial planar images was studied in 61 patients with AMI. In acute phase anterior, LAO 30 degrees and LAO 60 degrees myocardial images were collected. In 29 cases of 61 cases 3 to 6 hours delayed images could be collected. Each myocardial images was divided to 3 division and both images were compared. In 5 of 6 patients with marked increase of TL-uptake new defects were noted in anterior division of delayed images and in one case also in lateral division. In 7 patients of 12 patients with moderate increase of TL-uptake new defects were also noted in delayed images, i.e. 3 in anterior, 3 in inferior and one in apical division. It was concluded that over estimation of myocardial viability due to marked increase of TL-uptake was often noted in patients with AMI accompanying severe congestion. It became clear that delayed images were necessary to correctly estimate myocardial viability in such case.  相似文献   
37.
The CA-50 enzyme immunoassay kit (EIA kit) that has been developed with the use of C-50 monoclonal antibody prepared by L. Lindholm et al. was evaluated for diagnosis of human cancer. The levels of CA-50 in the sera were determined using this kit supplied from Mitsui Pharmaceuticals, Inc. Co. in 759 healthy donors, 728 patients with benign disease and 1,263 untreated patients with cancer. A CA-50 concentration of 40 U/ml of serum was used as the cut-off value. Patients with pancreatic cancer and patients with bile duct cancer had high positive incidence of 75% and 68%, respectively, compared with a low positive incidence of under 40% in patients with other cancers. On the other hand, positive rates in patients with benign disease were as low as 13%. Comparison of the serum levels of CA-50 with CA19-9 in the same samples did not exhibit complete positive correlation in patients with pancreatic cancer, patients with bile duct cancer and patients with liver cancer. These findings indicated that C-50 antibody reacted with two epitopes of CA19-9 and sialosyllactotetraose. From the above results, the usefulness of CA-50 as a tumor marker for pancreatic cancer and bile duct cancer was recognized with this EIA kit.  相似文献   
38.
39.
We present a case of primary ureteral carcinoma in the duplicated renal pelvis and ureter diagnosed by transurethral uretero-renoscopy. The case was of a 78-year-old man with the complaint of sudden asymptomatic macrohematuria. An excretory urogram strongly suggested the presence of duplication of the right collecting system, and cystoscopy revealed a gross hematuria from the right ureteral orifice. A retrograde ureteropyelogram revealed incomplete duplication of the right renal pelvis and ureter fused at about the ureter crossing over the iliac vessels, and a polyp-like filling defect in the lower segment of duplicated ureter at about 4 cm from the fusion of the ureters. Transurethral uretero-renoscopy was employed to investigate the filling defect, and a papillary tumor extended into the lower segment of duplicated ureter was revealed. Tumor was resected by a rigid operating instrument under transurethral uretero-renoscopy. The pathological diagnosis was grade I-transitional cell carcinoma of the ureter, so that right total nephroureterectomy with partial cystectomy was carried out subsequently. Surgical specimen after right total nephroureterectomy with partial cystectomy showed no other tumor in the pelvis or ureter macroscopically, and histopathological studies of surgical specimens were no evidence of malignancy. We believe that transurethral uretero-renoscopy significantly increases the diagnostic accuracy in determining the nature of upper urinary tract lesions, and this procedure is indispensable in the diagnosis of ureteral tumors. The present case was the 7th case of primary ureteral carcinoma in the duplicated renal pelvis and ureter in the Japanese literature.  相似文献   
40.
The inducibility of sister chromatid exchanges (SCEs) by benzo(a)pyrene (BP) was studied in cultured peripheral blood lymphocytes of 15 untreated lung cancer patients and 25 healthy persons including 11 high- and 14 low-cancer-risk individuals tentatively classified by the familial history of lung cancer and other neoplasms. The baseline SCE frequency in cultured lymphocytes was significantly high in lung cancer patients, as compared with all healthy persons or low-cancer-risk individuals. Following exposure to BP, the lymphocytes of lung-cancer patients and high-cancer-risk individuals exhibited significantly greater SCE yields than those of persons at low risk, although no significant difference was observed in the lymphocyte SCE yields when the levels of lung cancer patients were compared with those of all healthy persons. A comparison of the net SCE increase (delta SCE) in BP-exposed lymphocytes among the study groups, however, revealed a significant difference in delta SCE values only between high- and low-cancer-risk individuals. The present findings on both the observed SCE yields and delta SCE values suggest that lymphocytes of high-risk individuals may be more susceptible to BP-induced DNA damage than those of persons at low risk, and that such a chromosomal hypersensitivity to genotoxins may be associated with a high risk of neoplasms.  相似文献   
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