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41.
Eleven cases of histiocytic necrotizing lymphadenitis were studied. Originally four were misdiagnosed as cervical tuberculous lymphadenitis. The characteristic symptoms and signs were local tenderness, fever, leucocytopenia and good prognosis. Antibody to Epstein-Barr virus was elevated in 2 of 3 cases. Biopsy of the affected lymph node was necessary when the differential diagnosis from lymph node tuberculosis or malignant lymphoma could not be made. The characteristic histological feature was focal necrosis without neutrophil infiltration in cortical or subcortical areas. Ultrastructurally, we found characteristic inclusions ('tubulo-reticular structures') in histiocytes and lymphocytes. 相似文献
42.
Secretion in yeast of human lysozymes with different specific activities created by replacing valine-110 with proline by site-directed mutagenesis. 总被引:1,自引:1,他引:0 下载免费PDF全文
M Kikuchi Y Yamamoto Y Taniyama K Ishimaru W Yoshikawa Y Kaisho M Ikehara 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(24):9411-9415
Computer graphics indicate that a steric hindrance exists between valine-110 side chain of human lysozyme (EC 3.2.1.17) and an acetyl group of a modified substrate that contains N6,O-diacetylmuramic acid. To alter the substrate specificity of human lysozyme to be effective on the modified substrate, we replaced the valine-110 residue with various amino acids by site-directed mutagenesis. One of the mutant proteins (valine residue replaced with proline:P110) was secreted in Saccharomyces cerevisiae as at least four components (P110-A, P110-B, P110-C, and P110-D) with different specific activities. Two components, P110-B and P110-D, were isolated in a pure form and structurally characterized. The results suggest that this mutation lowered the lytic activity against Micrococcus lysodeikticus by changing a local conformation of the catalytic site while keeping almost the same substrate binding sites. Our results also indicate that cis/trans isomerization of prolyl peptide bonds probably occurs in vivo and that the conformational change of protein as well as point mutations in genes might influence the molecular evolution of the protein. 相似文献
43.
Yoshimitsu Kuroyanagi DR. ENG DR. SCI DR. MED ; Akihiko Shiraishi MD ; Yoshiteru Shirasaki MD ; Nobuaki Nakakita MD ; Yoshiaki Yasutomi MD ; Yasuo Takano MD ; Nobuyuki Shioya MD FACS 《Wound repair and regeneration》1994,2(2):122-129
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved. 相似文献
44.
O Hirai H Handa H Kikuchi M Ishikawa Y Kinuta 《No shinkei geka. Neurological surgery》1988,16(10):1141-1147
Lumbar subarachnoid pressure (LSP) was continuously monitored via intrathecally introduced polyethylene catheter to select the patients for shunt operation. A total of seventy cases included so-called normal pressure hydrocephalus (NPH) secondary to subarachnoid hemorrhage (SAH; 34 cases), idiopathic NPH (17 cases), secondary NPH whose symptoms developed after operations for brain tumors, head injuries or meningitis (12 cases) and other intracranial diseases including pseudotumor cerebri or meningeal carcinomatosis, etc. (7 cases). Shunt operation was effective in 36 cases and not effective in 9 cases, while 25 cases were not shunted since LSP was not elevated or clinical manifestations were slight. Mean values of baseline pressure and maximum pressure in shunt effective group, shunt non-effective group and non-shunted group were 14.5, 12.7, 9.0 and 29.9, 25.0, 17.9 mmHg, respectively. Statistical difference was observed between shunt effective group and non-shunted group. Frequency of pressure waves was also significantly higher in shunt effective group than in non-shunted group. Above all, measurement of LSP was regarded as useful in idiopathic NPH. However, preoperative clinical symptoms had a closer relationship to shunt response than results of LSP in post SAH patients. Complication related to this monitoring was negligible except in one case of meningitis which was easily treated by administration of antibiotics. Follow-up study also justified our selection since no further deterioration was noted in non-shunted group. The present study indicates that measurement of LSP would be useful in selecting the patients who will benefit from shunting and in eliminating unnecessary shunt operations because this simple method is easily performed at bed side without perforating the skull.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
45.
A Oikawa K Horaguchi R Sugawara J Kikuchi H Tohda K Takahashi A Wakui A Yamauchi T Nakada 《Cancer research》1986,46(2):989-993
Sensitivities to sister chromatid exchange (SCE) induction by chemicals of peripheral lymphocytes from 26 cancer patients were estimated under conditions identical to those for healthy humans which had been reported (Cancer Res., 43: 439-442, 1983). The sensitive individual was defined as one whose cells give a mean induced SCE frequency more than 2 standard deviation units above the population mean of induced SCEs in cells from the healthy humans. When cells were treated with 3-amino-1-methyl-5H-pyrido[4, 3-b]indole in the presence of rat liver S9 mix, 8 in 10 stomach cancer patients, 4 in 4 colon cancer patients, 3 in 9 lung cancer patients, 0 in 3 patients bearing other cancers, and 0 in 9 non-cancerous individuals were sensitive. The corresponding frequency of individuals in the healthy population, reported previously, was 1 in 33 persons. Thus, the frequency of sensitive individuals in the combined group of stomach and colon cancer patients was very significantly higher than were frequencies in control groups. Three in 10 patients with stomach cancer and 4 in 16 patients with other cancers were sensitive to induction of SCE by methyl methanesulfonate. Six in these 7 methyl methanesulfonate-sensitive patients were also 3-amino-1-methyl-5H-pyrido[4,3-b]indole sensitive. The frequency of methyl methanesulfonate-sensitive individuals in the healthy populations was 2 in 50. There was no patient who was sensitive to SCE induction by 4-nitroquinoline 1-oxide. The frequency was not significantly different from the healthy population, in which 3 in 50 persons were sensitive. These results suggest that a particular cancer correlates with the sensitivity of peripheral lymphocytes to SCE induction by particular chemicals. 相似文献
46.
With the advent of magnetic resonance imaging (MRI), the neurohypophyseal system can be clearly delineated and its functional integrity can be predicted. The authors describe seven cases of central diabetes insipidus (DI) that occurred spontaneously. MRI revealed that the normal hyperintensity of the pituitary posterior lobe, which has been thought to be the neurosecretory material containing antidiuretic hormone, was absent in all cases. In addition, enlargement of a part of the neurohypophyseal system was recognized in five of seven cases on MRI. Three of the five patients with enlargement of a part of the neurohypophyseal tract underwent biopsy and were demonstrated to have chronic inflammation of the neurohypophyseal system. It was demonstrated that the enlarged parts of the neurohypophyseal system had shrunk either spontaneously or after the biopsy in four of the five cases. All patients are alive and have not experienced progression or remission of the disease. This study indicates that some cases of idiopathic DI result from a tiny mass lesion, usually nonneoplastic, localized in the neurohypophyseal system. 相似文献
47.
Yoshitomo Kashiwagi Chikara Kikuchi Jun-ichi Anzai 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(1):51-55
Electrocatalytic dehalogenation of organohalides was studied using a nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode. The nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode was prepared by attaching nickel(II) (6-(2′-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)perchlorate chemically to the carboxyl groups of a thin poly(acrylic acid) layer coated on the graphite felt. The modified electrode gave a reversible electron transfer for the nickel(II)/nickel(I) redox couple in cyclic voltammetry at ?0.95 V versus Ag/AgCl. A preparative electrocatalytic dehalogenation of organohalides was successfully achieved on the modified electrode with an adequate current efficiency (55.6–94.8%), conversion (34.2–100%) and turnover number of the Ni catalyst (667–3333). 相似文献
48.
Osamu Kikuchi Hiroyuki Murai Koji Ikezoe Masakazu Kawajiri Yasumasa Ohyagi Emiko Isogai Jun-ichi Kira 《Clinical neurology》2004,44(4-5):299-302
A 58-year-old woman suffered from stiffness, swelling, rubor and muscle pain in the extremities one month after she climbed a mountain in Kyushu, an island in southern Japan. On admission, mild proximal weakness was present in the extremities. Her range of motion in the extremities was limited due to firm skin and subcutaneous stiffness which was similar to scleroderma. She showed peripheral blood eosinophilia and hypergammaglobulinemia as well as a high erythrocyte sedimentation rate. An IgM antibody against Borrelia afzelii was positive. MRI of the skeletal muscles demonstrated enhancing fascia around the biceps brachii muscle, and a biopsy specimen revealed perivascular infiltration of mononuclear cells within the hypertrophic fascia. Eosinophilic infiltration was absent. We treated the patient with prednisolone, doxycycline and amoxicillin, which alleviated the symptoms. This is the first report to show that Borrelia afzelii was involved in eosinophilic fasciitis. 相似文献
49.
50.
Yohei Ogawa Makoto Hiura Toru Kikuchi Keisuke Nagasaki Yukie Iwata Makoto Uchiyama 《Clinical Pediatric Endocrinology》2004,13(1):55-58
This study aimed to investigate the levels of serum low-density lipoprotein
cholesterol (LDLC) using direct measurement in healthy Japanese school children. The
subjects were 621 children (325 boys and 296 girls) aged 9 to 10 in the 4th grade, and 688
children (334 boys and 354 girls) aged 12 to 13 in the 7th grade. The levels of serum LDLC
and high-density lipoprotein cholesterol were measured by direct determination (Cholestest
LDL and Cholestest NHDL; Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan). In boys in the
4th grade, the mean, the 75th, the 90th and the 95th percentiles of LDLC levels (mg/dl)
were 91.6, 104, 124 and 134, respectively. In girls in the 4th grade, they were 92.8, 108,
122 and 130. In boys in the 7th grade, they were 83.4, 96, 113 and 123. In girls in the
7th grade, they were 93.0, 106, 126 and 137. Serum LDLC levels in boys in the 7th grade
were lower than those of other groups. The direct measurement of serum LDLC level is
useful for evaluation of dyslipidemia in healthy school children, because the method is
applicable to non-fasting serum. 相似文献