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Hidetaro Mori Keisuke Hiraoka Ryoichi Yorifuji Tohru Iwasaki Syuzo Gomikawa Ohshi Inagaki Seishi Inoue Yoshihiro Takamitsu Yoshikazu Fujita 《Artificial organs》1994,18(10):725-728
Abstract: The adsorptive characteristics of 5 dialysis membranes for recombinant human erythropoietin (EPO) were studied in vitro in a closed circuit system. For 120 min, EPO added with bovine serum was significantly adsorbed by polymethylmetacrylate (PMMA) and polyacry–lonitrile (PAN) membranes but not by Cuprophan, ethylene vinyl alcohol (EVAL), or polysulfone (PS) membranes. In addition the EPO adsorptive rate, as well as that of β2 –microglobulin (β2 –MG), was greater with a PMMA membrane than with a PAN membrane. EPO was not detected in the ultrafiltrate at 15 min with 5 membranes. These results indicate that EPO was eliminated by membrane adsorption only with some dialysis membranes. 相似文献
3.
T Abumiya I Sayama K Asakura H Hadeishi M Mizuno A Suzuki N Yasui F Shishido K Uemura 《No shinkei geka. Neurological surgery》1990,18(9):837-844
Regional effects of craniotomy on cerebral circulation and metabolism, such as regional cerebral blood flow (rCBF), regional cerebral oxygen consumption (rCMRO2), regional oxygen extraction fraction (rOEF), and regional cerebral blood volume (rCBV) were examined by a PET (positron emission tomography) study concerning surgery that was performed on unruptured aneurysm patients. Eight patients with intracranial un-ruptured aneurysms were studied pre- and post-operatively by the 15O labelled-gas steady-state method, using HEADTOME-III. All patients underwent aneurysmal surgery performed by the transsylvian approach. There was a significant increase in the mean OEF values taken from the whole-brains of 8 patients, but there was not a significant change in CBF, CMRO2 or CBV. The increase in OEF was caused by decrease of O2 content, which was caused by post-operative decrease in the Hb value. So, this OEF increase was not the direct effect of craniotomy. In 2 patients, the rCBF and rCMRO2, in the fronto-temporal region (where craniotomy was performed) increased post-operatively. This regional effect suggests transient reactive hyperemia following compressive ischemia during the operative procedure, and metabolic demands for recovery of brain function. In 2 other patients, who had relatively low rCBFs during the pre-operative study, rCBF and rCMRO2 in the bi-frontal region had decreased more at the post-operative study. This change appears to have been caused by removal of cerebrospinal fluid and depression of the frontal lobe. From this study, it becomes evident that the regional effect of craniotomy on cerebral circulation and metabolism is not so great, when adequate microsurgical techniques are used. 相似文献
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Akira Ishih Toshio Miyase Tohru Suzuki Francis W. Muregi Mamoru Terada 《Journal of natural medicines》2007,61(2):213-216
Febrifugine and isofebrifugine alkaloid mixtures extracted from the leaves and buds of Hydrangea macrophylla var. Otaksa, collected during different months, in Japan, were quantified using high-performance liquid chromatography. Leaves collected
during the flowering season, namely from June to August, contained 0.16–0.31 mg/g of the alkaloid mixture, whereas those collected
from September to December had less than 0.03 mg/g of the mixture. However, extracts of buds harvested from October to February
contained a consistently larger amount (more than 0.49 mg/g) of the alkaloids. Hot-water extracts from the leaves and buds
collected during different seasons were evaluated for antimalarial activity against Plasmodium yoelii 17XL in mice. The extract of leaves collected in August demonstrated high antimalarial activity, and all mice that received
the extract survived the infection. In contrast, the extract of leaves collected in December showed little activity. The extract
of buds collected in December cleared parasites, but with subsequent mortality to mouse. The present results show that the
amount of antimalarial agent—febrifugine and isofebrifugine mixture—in H. macrophylla var. Otaksa is both part- and season-dependent, suggesting that the choice of plant parts and their harvesting season are important factors
worth considering in the pharmacological use of medicinal plants. 相似文献
6.
A T Farrell I Papadouli A Hori M Harczy B Harrison W Asakura M Marty R Dagher R Pazdur 《Annals of oncology》2006,17(6):889-896
PURPOSE: This paper summarizes the role of external advisors in oncology drug development and regulation from a global perspective. DESIGN: Recently, representatives from the United States Food and Drug Administration, European Medicines Agency, the Japanese Pharmaceuticals and Medical Devices Agency, the Australian Therapeutic Goods Administration and Health Canada held a meeting in conjunction with the American Society of Clinical Oncology meeting. The role of external advisors in oncology drug development and regulation in each of these jurisdictions was presented and discussed. RESULTS: All regulatory bodies described have experience with two forms of outside expertise: advice from individual experts and advice from a group of experts assembled as an advisory group. Regulatory jurisdictions use individual experts variably. In some regions, individual experts provide advice based on knowledge and experience during the drug development phase or in the planning phase for the submission of a drug registration package. In other regions, these individuals serve as external evaluators with the primary responsibility for the review of a clinical trials package submitted for drug registration. Advisory boards have been formalized in all jurisdictions discussed. Advisory boards have a role in discussing specific applications as well as broad policy issues. A common theme is a composition of a core panel of experts with augmentation by additional expertise as needed for consideration of specific scientific questions. In all jurisdictions, advisory board recommendations are not binding on the regulatory body. CONCLUSIONS: Global oncology drug development and registration involves the use of experts by regulatory authorities. The types of experts needed, the expert's role and the transparency of the advisory process reflect the individual needs in different regions. 相似文献
7.
Benign schwannoma of the pancreas 总被引:2,自引:0,他引:2
Labile Togba Soumaoro Kenichi Teramoto Tohru Kawamura Noriaki Nakamura Takahiro Sanada Kenichi Sugihara Shigeki Arii 《Journal of gastrointestinal surgery》2005,9(2):288-290
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were
diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma
occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic
masses is briefly discussed. 相似文献
8.
Yukio Fukuyama Tohru Seki Chikaya Ohtsuka Hisao Miura Michiko Hara 《Brain & development》1996,18(6):144-484
Recent studies have shown that adequate medication can prevent the recurrence of febrile seizures (FS). It has also been clarified that the vast majority of, though not all, FS patients follow a benign course. Then, questions arise as to whether or not FS should be prevented, particularly in light of the risks of side effects from drugs. Which kinds of FS can be prevented, if necessary? The guidelines presented here are aimed primarily at helping general practitioners in considering how to manage FS most appropriately. The guidelines stress that judgements should be individualized, while referring to a few specific ‘warning factors’. The guidelines follow a ‘laissez-faire’ principle for the majority of FS cases, whereas intermittent therapy with diazepam and continuous medication with either phenobarbital or valproate are indicated in other limited cases meeting respective definite criteria. 相似文献
9.
Oral adsorbent (AST-120) reduces blood levels of urea and creatinine in experimental studies. It has also been shown to retard the progression of chronic renal failure in clinical studies. In the present study, the effect of AST-120 was examined in the rat model of subtotal nephrectomy (sNPX). This experimental model of chronic renal failure is characterized by glomerular hyperfunction, glomerular hypertrophy, increased mesangial trapment of macromolecules and subsequent glomerular sclerosis. We report the effect of AST-120 on glomerular hyperfunction, glomerular hypertrophy and mesangial trapment of macromolecules in the early stage and glomerular function and histology in the late stage of the rat model of sNPX. From 2 days after sNPX, rats were fed regular rat chow with (AST group: AST) or without (control) AST-120. At 2 weeks, iron dextran (ID) was injected intravenously. Three days after the injection, mesangial trapment of ID was largely ameliorated in AST when compared with control (p less than 0.02). The value of mean planar area of glomerulus (PAmean) in AST was significantly lower than that in control (p less than 0.05). At 2 and 9 weeks, the values of GFR and RPF in AST were all statistically higher than those in control. At 9 weeks, whereas average glomerular sclerosis index (SI: 0-4 scale) was 1.07 in control, significantly lower SI (0.57) was noted in AST (p less than 0.05). Thus, AST-120 has effects on glomerular hypertrophy, increased mesangial trapment of macromoleculus and finally the progression of chronic renal failure in the rat model of sNPX. The effects are not through reducing glomerular hyperfunction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献