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61.
A. Komiyama I. Kamo S. Furukawa S. Akazawa K. Hirayama E. Satoyoshi 《Journal of neurology》1988,235(4):207-213
Summary Antibodies against phosphate-buffered-saline extracts (SE) of non-acetylcholine receptor (AChR) skeletal muscle antigens were found in patients with myasthenia gravis (MG). The antigenicity of SE was distributed in three fractions with molecular masses of over 200 kDa, 90–150 kDa and 7–14 kDa on gel filtration. These fractions shared common antigenicities. Further analysis of 90–150 kDa fractions on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed five major bands, ranging from 105 kDa to 275 kDa. The antibodies against SE were detected in 52% (58/112) of the MG patients; incidence and titres were higher in the thymoma group (n=21; 90% and 0.872 respectively) than in the non-thymoma group (n=91; 43% and 0.200, P<0.001). In patients without a thymoma, these antibodies were frequently observed in late-onset disease and the severe generalized form (P<0.01). In 4 of 7 ocular MG patients without anti-AChR antibodies, low but appreciable levels of anti-SE antibodies were found. In 73% (11/15) of generalized MG patients treated with prednisolone and thymectomy, anti-SE antibody titres changed in association with those of anti-AChR antibodies and with the clinical course. Both antibody titres increased synchronously in patients who developed crises. 相似文献
62.
Carla Ghelardini Alessandro Quattrone Nicoletta Galeotti Silvia Livi Grazia Banchelli Laura Raimondi Renato Pirisino 《Neuropsychopharmacology》2003,28(6):1096-1105
Amphetamine (AMPH) is an indirect sympathomimetic compound classified as a substrate-type releaser that distinguishes it from other stimulants that act as uptake 1 blockers, such as cocaine (COC). In mammals, AMPH elicits central stimulation, hypermotility, anorexia, analgesia and analeptic activity, mainly through the increase of extracellular brain dopamine (DA). The inversion of vesicular transporters and/or intravesicular alkalinization is assumed to have a role in AMPH-induced exocytosis. However, the action mechanism of this compound has not yet been completely clarified. Recent evidence on the action of AMPHs indicates potassium channel-blocking properties in peripheral tissues. We investigated the possible involvement of a Shaker-like Kv1.1 channel subtype in the central effects of AMPH, using an antisense oligodeoxyribonucleotide (aODN) that specifically and reversibly inhibits the expression of these channels in the brain. The effect of aODN pretreatments was studied by evaluating the modification of behavioral effects induced in mice through the intracerebroventricular administration of AMPH, COC, or other compounds. The aODN in mice almost completely blocked the stimulatory effects of AMPH and other releasers but was ineffective in reducing the central activity of COC. In aODN-pretreated rats a strong reduction of the AMPH, but not of the COC-stimulated DA efflux from nucleus accumbens was observed. Our results suggest that the stimulant effects of AMPH and chemically related compounds, but not COC, require the presence of functionally active Kv1.1 channels in the brain. 相似文献
63.
Flavio Masi Benedetta Leggio Giulio Nanni Simona Scheggi M Graziella De Montis Alessandro Tagliamonte Silvia Grappi Carla Gambarana 《Neuropsychopharmacology》2003,28(4):683-693
Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB. 相似文献
64.
Jonathan H. Marsh Willi Kreis Barbara Barile Silvia Akerman Philip Schulman Steven L. Allen Linda C. DeMarco Michael W. Schuster Daniel R. Budman 《Cancer chemotherapy and pharmacology》1993,31(6):481-484
Summary Eight patients, of whom four had acute myeloid leukemia (AML) and four had chronic myeloid leukemia (CML) blast crisis, were treated with a combination of cytosine arabinoside (ARA-C: 1,600 mg/m2 in three patients, 1,200 mg/m2 in five patients), tetrahydrouridine (THU: 2,800 mg/m2 in two patients, 2,646 mg/m2 in one patient, 2,100 mg/m2 in five patients), and carboplatin (900 mg/m2 in four patients, 720 mg/m2 in one patient, 450 mg/m2 in three patients). As a result of this treatment, five of the eight patients became aplastic. Two of the four patients with CML blast crisis reverted to the chronic phase and two of the four patients with acute nonlymphocytic leukemia (ANLL) attained a remission (one partial remission and one complete remission). The major toxicities included myelosuppression, unacceptable hepatotoxicity, and diarrhea. Pharmacokinetics studies revealed that the addition of carboplatin did not significantly change the disposition of ARA-C. ARA-C levels were not significantly changed in comparison with those obtained in a prior study of ARA-C with THU (ARA-C plasma levels at 3 h, 2630±1170 ng/ml).Supported by the Don Monti Memorial Research Foundation 相似文献
65.
Leonardo A Sechi Giovanna E Felis Niyaz Ahmed Daniela Paccagnini Donatella Usai Silvia Ortu Paola Molicotti Stefania Zanetti 《Infection, genetics and evolution》2007,7(4):424-432
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism. 相似文献
66.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
67.
Polycationic biocides with pendant active groups: molecular weight dependence of antibacterial activity. 总被引:2,自引:0,他引:2
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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
68.
69.
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
70.
Dr Jonas Hähnel MD Wolfgang Friesdorf MD Bernhard Schwilk MD Thomas Marx MD Silvia Blessing 《Journal of clinical monitoring and computing》1992,8(1):1-6
The technical equipment of today's intensive care unit (ICU) workstation has been characterized by a gradual, incremental accumulation of individual devices, whose presence is dictated by patient needs. These devices usually present differently designed controls, operate under different alarm philosophies, and cannot communicate with each other. By contrast, ICU workstations could be equipped permanently and in a standardized manner with electronically linked modules if the attending physicians could reliably predict, at the time of admission, the patient's equipment needs. Over a period of 3 1/2 months, the doctors working in our 20-bed surgical ICU made 1,000 predictions concerning outcome, equipment need, duration of artificial ventilation, and duration of hospitalization for 300 recently admitted patients. The interviews were made within the first 24 hours after admission. The doctors being interviewed were usually (i.e., in over 90% of cases) unfamiliar with the patient. Information concerning the patient's general state of health, special pre-ICU events, and complications was offered to the interviewed clinician because this information represents standard admission data. It was found that the equipment need (represented by two different setups, high tech and low tech) could be predicted most reliably (96.4% correct predictions) compared with a prediction on outcome of ICU treatment (94.5%), on duration of artificial ventilation (75.4%), and on duration of stay (43.4%). There was no significant (p>0.05) difference in the reliability of predictions between residents and consultants. Factors influencing the postoperative equipment need varied with surgical specialty. The general state of health, as indicated by the ASA classification (p<0.001), and the specific intervention (all multiple-valve replacements needed the high-level equipment standard) appeared to be most important in cardiac surgery, while a state of septicemia was important in general surgery (p<0.001). Our findings suggest that ICU workstations may be standardized into at least two types. 相似文献