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41.
Kiyotaka KUROSE Toshikazu MASUMOTO S. M. Fazle AKBAR Kojiro MICHITAKA Norio HORIIKE Morikazu ONJI 《Digestive endoscopy》1997,9(1):34-37
Abstract: Fifty -two patients with primary biliary cirrhosis (PBC), 10 of whom were 65 years or older at the time of diagnosis, were investigated by laparo-scopy. Laparoscopic findings in these 10 patients were evaluated and compared with those in younger patients. The 10 cases were composed of nine females and one male, and two had been diagnosed as having symptomatic PBC with skin itching, while the remaining eight had asymptomatic PBC. Two, seven and one case were in Scheuer's stage I, II and III, respectively, and eight had chronic non-suppurative destructive cholangitis (CNSDC) on liver biopsy specimens. The majority of senescent PBC patients had typical findings of the early stage of PBC on the liver surface; mild undulations in nine and reddish patches in eight. The laparoscopic findings in senescent PBC were relatively mild. 相似文献
42.
Polycationic biocides with pendant active groups: molecular weight dependence of antibacterial activity. 总被引:2,自引:0,他引:2 下载免费PDF全文
T Ikeda H Hirayama H Yamaguchi S Tazuke M Watanabe 《Antimicrobial agents and chemotherapy》1986,30(1):132-136
Two types of polycations with pendant active groups were synthesized: one is polymethacrylate containing pendant biguanide units, and the other is poly(vinylbenzyl ammonium chloride). The two polycations were found to exhibit higher bactericidal activity against Staphylococcus aureus than the corresponding monomers. Fractionation of the polycations was successfully performed on gel filtration chromatography, and examination of the antibacterial activity against S. aureus of the well-characterized polymer samples with various molecular weights (MW) revealed that the activity was strongly dependent on the MW of the polycations and that there existed an optimal MW range for the cidal action of the polymeric biocides. Experiments on the lysis of protoplasts of Bacillus subtilis in contact with the polycations have shown that target sites of the polycationic biocides are cytoplasmic membranes of bacteria. 相似文献
43.
44.
Norio Ohkoshi Hldehlro Mizusawa Nobuko Shiraiwa Shin'Ichi Shoji Katsutoshi Harada Kazuo Yoshizawa 《Muscle & nerve》1995,18(11):1265-1271
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc. 相似文献
45.
Effects of nilvadipine on the low- and high-voltage activated Ca2+ currents (LVA and HVA ICa, respectively) were compared with other organic Ca2+ antagonists in acutely dissociated rat hippocampal CA1 pyramidal neurons. The inhibitory effects of nilvadipine, amlodipine and flunarizine on LVA ICa were concentration- and use-dependent. The apparent half-maximum inhibitory concentrations (IC50s) at every 1- and 30-s stimulation were 6.3×10−7 M and 1.8×10−6 M for flunarizine, 1.9×10−6 M and 7.6×10−6 M for nilvadipine, and 4.0×10−6 M and 8.0×10−6 M for amlodipine, respectively. Thus, the strength of the use-dependence was in the sequence of nilvadipine>flunarizine>amlodipine. Nilvadipine also inhibited the HVA ICa in a concentration-dependent manner with an IC50 of 1.5×10−7 M. The hippocampal CA1 neurons were observed to have five pharmacologically distinct HVA Ca2+ channel subtypes consisting of L-, N-, P-, Q- and R-types. Nilvadipine selectively inhibited the L-type Ca2+ channel current which comprised 34% of the total HVA ICa. On the other hand, amlodipine non-selectively inhibited the HVA Ca2+ channel subtypes. These results suggest that the inhibitory effect of nilvadipine on the neuronal Ca2+ influx through both LVA and HVA L-type Ca2+ channels, in combination with the cerebral vasodilatory action, may prevent neuronal damage during ischemia. 相似文献
46.
Primary brain stem lesions caused by closed head injuries 总被引:3,自引:0,他引:3
Takuo Hashimoto Norio Nakamura Karl-Eduard Richard Reinhold A. Frowein 《Neurosurgical review》1993,16(4):291-298
Traumatic lesions of the brain stem are of two types: primary, which are considered to be caused at the moment of impact, and secondary, associated with supratentorial mass lesion. Of the 239 patients with a serious head injury who showed a severe disturbance of consciousness upon admisision and who had CT scan carried out immediately, 21 cases were considered to have a primary brain stem lesion with initial CT scan. A primary brain stem lesion was found in 21 of 239 (8.8%) of patients with serious head injury. Their injuries were caused primarily by traffic accidents. Sixteen of the 21 cases showed not only brain stem lesions but also other brain injuries such as cerebral contusion of the white and gray matter, callosal injury, intraventricular hemorrhage, and subarachnoid hemorrhage, which are considered to be caused by a diffuse shearing injury. Five cases who showed a single injury to the brain stem with no other brain lesions were considered to have a pure brain stem lesion. Primary brain stem lesions were observed on the dorsal side of the midbrain, where they can be differentiated from secondary brain stem lesions. These lesions are considered to result from the shearing mechanism in and around the brain stem very close to the tentorial edge, or to an injury of the lower brain stem by hyperextension of the cervical vertebrae. The prognosis of patients with a primary brain stem lesion was usually unfavorable, except in those with a single brain stem lesion. 相似文献
47.
Tomoyuki Yamashita M.D. Yoshihide Fujimoto M.D. Takaya Kodama M.D. Akira Hirayama M.D. Takao Obara M.D. Yukio Ito M.D. Motohiko Aiba M.D. Kiyoko Kusakabe M.D. 《World journal of surgery》1988,12(4):559-563
Clinicopathologic studies were performed to establish rational criteria for total thyroidectomy as a treatment of follicular carcinoma. During the 4-year period from 1981 to 1984, total thyroidectomy was carried out on 23 patients in whom unequivocal vascular invasion and/or obvious extracapsular extension were disclosed on pathological study of the primary thyroid lesion. Although occult metastatic lesions were detected postoperatively in 5 patients, no distant metastases have been found in 12. Distant metastasis was clinically manifest on admission in the other 6 patients. The degree of vascular invasion at the primary lesion was not correlated with the occurrence of distant metastasis. However, 10 of the 15 patients with tumors characterized by a thick fibrous capsule had distant metastases, while all but 1 of 8 patients with a thin capsule showed no metastasis. Apparent capsular invasion seemed to increase the relative risk of distant metastasis. On the other hand, solid clusters of tumor cells containing a variable number of small follicles, which characterize Langhans' wuchernde Struma, were found in 6 patients, and 5 of them showed distant metastases. Thus, total thyroidectomy should be considered when (a) distant metastases are clinically apparent, (b) the primary lesion has a thick fibrous capsule with or without obvious capsular invasion, or (c) solid clusters of tumor cells are demonstrated microscopically.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
Resumen Se realizaron estudios clinicopatológicos con el propósito de establecer criterios racionales para la tiroidectomía total en el tratamiento del carcinoma folicular. En el curso de un perfodo de 4 anos entre 1981 y 1984, se realizó tiroidectomía total en 23 pacientes en quienes se halló inequívoca invasión vascular y/o obvia extension extracapsular en el examen histopatológico de la lesión tiroidea primaria. Aunque postoperatoriamente se detectaron lesiones metastáticas ocultas en 5 pacientes, no se encontraron metástasis distantes en 12. Metástasis distantes eran clínicamente manifiestas en el momenta de la admisión en los otros 6 pacientes. El grado de invasión vascular en la lesión primaria no apareció correlacionado con la ocurrencia de metástasis distantes. Sin embargo, 10 de los 15 pacientes con tumores caracterizados por una cápsula gruesa y fibrosa tenían metástasis distantes, mientras solo 1 de 8 pacientes con tumores de cápsula fina mostró metástasis. La invasión capsular aparente parece incrementar el riesgo relativo de metástasis distantes. Por otra parte, agrupaciones sólidas de células tumorales con presencia de números variables de folículos pequeños, que caracterizan al wuchernde Struma de Langhans, fueron encontrados en 6 pacientes, 5 de los cuales mostraron metastasis distantes. Por lo tanto, se debe considerar la tiroidectomía total cuando: (a) haya metástasis distantes clínicamente aparentes, (b) la lesión primaria tenga una gruesa cápsula fibrosa con o sin invasión capsular obvia, y (c) se demuestren microscópicamente agrupaciones sólidas de células tumorales.
Résumé Une étude clinicopathologique a été menée pour déterminer les critères de thyroïdectomie totale comme traitement dans le cancer folliculaire de la thyroïde. Pendant 4 ans, de 1981 à 1984, 23 patients ont subi une thyroïdectomie totale pour envahissement vasculaire non équivoque et/ou extension extracapsulaire évidente découverte sur la pièce d'exérèse initiale. Cinq patients avaient des métastases occultes découvertes dans la période postopératoire, 6 avaient des métastases cliniquement évidentes, alors que 12 ne présentaient aucun signe de métastase à distance. Le degré d'envahissement vasculaire de la lésion primitive n'était pas corrélé avec la survenue de métastases à distance. Cependant, 10 des 15 patients à tumeurs caractérisées par un épaississement de la capsule fibreuse avaient des métastases à distance, alors que 7 des 8 patients avec une capsule mince n'avaient pas de métastases. L'envahissement capsulaire était associé à un plus grand risque de métastases à distance. Des amas solides de cellules tumorales contenant de petits follicules, le wuckernde struma de Langhans, étaient retrouvés dans 6 cas, dont 5 avaient des métastases à distance. Ainsi, la thyroïdectomie totale est préconisée lorsque (a) des métastases à distance sont cliniquement évidentes, (b) la lésion primitive possède une capsule fibreuse épaisse avec ou sans envahissement évident, et (c) on met en évidence des cellules tumorales en amas microscopiquement.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987. 相似文献
48.
We have designed a new instrument that we have called a skull punch, which is useful and safe for making a burr hole for a purely osteoplastic craniotomy in neonates and infants. The instrument is described in detail. 相似文献
49.
We presented a report on four cases of juvenile parkinsonism with a marked diurnal fluctuation of symptoms and dystonia. Among parkinsonian signs, rigidity fluctuated the most and increasing rigidity by passive or active movements or emotional stress was observed. When we analyzed patients previously reported, in addition to our own new patients, apart from the diurnal fluctuation and predominant occurrence in females, many similarities to Yokochi's third group of juvenile parkinsonism were found. In the previous reports, the patients with the marked fluctuation of parkinsonian symptoms have not always shown dystonia. The changes of symptoms in relation to menstruation and pregnancy were other characteristic features in our three female patients. Here we proposed that for the present, it is preferable to call this disorder "juvenile parkinsonism with a marked diurnal fluctuation." 相似文献
50.
Murdiastuti K Miki O Yao C Parvin MN Kosugi-Tanaka C Akamatsu T Kanamori N Hosoi K 《Pflügers Archiv : European journal of physiology》2002,445(3):405-412
By Western blot analysis, the expression level of aquaporin (AQP) 5 in the submandibular gland (SMG) was found to be different among individual rats of the Sprague-Dawley (SD) strain. Such differences were observed for AQP5 but not for AQP1 and consequently the SD strain was divided into two groups, one expressing a high level of AQP5 and the other a low one. The difference in average intensity of expression between the two groups was more than twofold. Immunohistochemical analysis of the SMG demonstrated that the AQP5 protein was localized in the basal and apical/lateral plasma membrane of acinar cells in rats expressing the high level of AQP5. In the rat expressing the low level, however, this channel protein was localized strongly in the apical/lateral plasma membrane, but only very weakly in the basal membrane of the acinar cells. Such a diverse localization of AQP5 was confirmed by Western blotting as well. Breeding between brother and sister was repeated for two times within high expressers and low expressers to obtain the third generation progenies (F2); the AQP5 level of the SMG in the third generation (F2 rats) from high expressers was significantly higher than the F2 from low expressers. Our present study suggests the existence of genetic variation in the expression of a water channel protein, AQP5, in rats. 相似文献