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21.
A 68-year-old man had subacute cerebellar degeneration and a non-Hodgkin's lymphoma. Using an immunoblotting method, we found serum antibodies to rat cerebral 250-kd and 110-kd and cerebellar 110-kd acidic cytoplasmic proteins. The antibodies did not react unless the antigens were prepared soon after death with protease inhibitors. Two hundred fifty-kd and 110-kd proteins are minor components of soluble cytoplasmic proteins of the brain. The molecular weights differed from other soluble brain-specific proteins already characterized. 相似文献
22.
Aoyama Takao Yamamoto Koujirou Kotaki Hajime Sawada Yasufumi Iga Tatsuji 《Pharmaceutical research》1997,14(11):1601-1606
Purpose. The locomotive activity changes after intravenous (i.v.) administration of methylphenidate (MPD) in rats were pharmacodynamically analyzed.
Methods. MPD concentration in plasma, MPD concentration and dopamine (DA) level in striatal dialysate collected by microdialysis method, and the locomotor activity after i.v. administration of MPD (2, 5 and 10 mg/kg doses) were used for the analysis.
Results. The transport of MPD from plasma to the interstitial fluid in the brain could be expressed by the linear two-compartment model. The clockwise hysteresis between the MPD concentration and the DA level in the dialysate could be explained by the pharmacodynamic model considering Michaelis-Menten type reuptake process of the extracellular DA into the terminal of the dopaminergic nerve and its competitive inhibition by the extracellular MPD. The inhibition constant (Ki) of MPD for DA reuptake was estimated to be 41.3 ± 73.8 nM (mean ± SE), which was closely consistent with the in vitro value after correction with dialysis recovery. The relationship between DA level in dialysate and locomotor activity was expressed by the Emax model considering two contrary effects, hyperkinesia and stereotypy. The bi-phasic locomotor activity-time profiles after high dose of MPD could be represented by this model.
Conclusions. The developed model made it possible to explain the tolerance in DA increase and the complicated locomotive change induced by MPD, and may be useful for other DA reuptake inhibitors, such as amphetamine and methamphetamine. 相似文献
23.
Nobuhiro Kawatsuki Ken Takatani Tohei Yamamoto Osamu Sangen 《Macromolecular chemistry and physics.》1997,198(9):2853-2866
Photoreactive (meth)acrylate monomers having mesogenic groups based on 4-hexyloxy-4′-(3-methyl-2-butenyloxy)biphenyl and 4-hexyloxy-4′-(2-butenyloxy)biphenyl were synthesized. Methacrylate monomers ( 3c, d ) and acrylate monomer having 3-methyl-2-butenyloxy group ( 3b ) were polymerized by free radical mechanism; the acrylate monomer having 2-butenyloxy group ( 3a ) caused gelation during the polymerization. To obtain photoreactivity, 4-benzoylphenyl (meth)acrylates were radically copolymerized with monomers 3b and 3d . Thermal behavior of (co)polymers was determined by differential scanning calorimetry, polarized optical microscopy and temperature-controlled X-ray analysis. (Co)polymers showed liquid-crystalline behaviour with nematic and smectic phases. UV-irradiation was used to photochemically crosslink copolymer films, and the resultant films were insoluble in organic solvents. The uniaxially oriented copolymer thin film was photo-crosslinked and showed thermally stable orientation. 相似文献
24.
Takashi Shuto Yutaka Ohtsubo Ken'ichi Sekido Hiroko Iwamoto Isao Yamamoto 《Child's nervous system》1996,12(2):107-109
We report the case of an infant with a cerebellar astrocytoma that showed marked calcification within only 6 months. In general, only slow-growing tumors tend to calcify. To our knowledge, no other case of such rapid calcification in cerebellar astrocytoma has been reported. 相似文献
25.
Detection of nephritogenic antigen from the Lewis rat renal tubular basement membrane 总被引:1,自引:0,他引:1
H Yoshida Y Wakashin S Ueda R Azemoto K Iesato S Yamamoto T Mori M Ogawa Y Mori M Wakashin 《Kidney international》1990,37(5):1286-1294
Immunopathogenicity of trypsin-solubilized or non-solubilized renal tubular basement membrane (TBM) of the Lewis (LEW) rat was investigated. Autoimmune tubulointerstitial nephritis (TIN) was induced in BALB/c mice by immunization with trypsin-solubilized LEW rat TBM, while immunization with non-solubilized TBM did not produce the disease. Based on this preliminary experiment we studied the characterization of immunogenic and nephritogenic TBM antigen of the LEW rat. TIN was characterized by severe mononuclear cell infiltrates with multi-nucleated giant cells in the interstitium, tubular destruction and intensive IgG and C3 deposits along the TBM. Anti-TBM antisera and eluate from the nephritic mouse kidneys reacted with the TBM of normal LEW rat kidney by immunofluorescence. LEW rat TBM was also detected immunofluorescently by using antisera from BALB/c mice immunized with autologous trypsin-solubilized TBM. A competitive inhibition test revealed a higher titer of anti-TBM antibody in the eluate than in the adsorption-treated antisera per microgram IgG. Immunoblotting showed one reactive band with a molecular weight of 45,000 daltons, and the blotting patterns in tryptic TBM of the Brown Norway (BN) and LEW rats appeared similar. Amino acid analysis of nephritogenic LEW rat tryptic TBM showed that it contained no hydroxyproline and hydroxylysine, suggesting that this TBM preparation was not collagenous. These findings suggest that tryptic digestion contributes to the release of nephritogenic antigen from the LEW rat TBM and that this antigen system might participate in the immune system involved in the anti-TBM associated TIN that is well known to be induced by non-digested TBM of TBM antigen positive animals. 相似文献
26.
27.
S Nakano S Suzuki H Kinbara Y Maeda M Yanagawa K Tajima H Tochigi J Kawamura S Hounoki I Yamamoto 《Hinyokika kiyo. Acta urologica Japonica》1990,36(7):831-835
This is a case report on a patient with double cancer of kidney and urinary bladder. The patient was a 65-year-old female, and she was admitted with the chief complaint of gross hematuria and right flank pain. After careful examinations, she was diagnosed with right nonfunctioning kidney caused by invasive bladder cancer. Computerized tomography incidentally revealed a mass in the upper pole of the left kidney. Selective left renal arteriography showed stretched arteries and irregularity and tortuosity of the smaller vessels. She was diagnosed with double cancer of bladder and left kidney. Owing to the damage of the right renal function, left partial nephrectomy, total cystectomy, right nephroureterectomy and left ureterocutaneostomy were performed. According to DMSA scintigraphy measured 15 days later, the uptake value of the left kidney was 13.25%, compared to the preoperative value of 25.62%. To date, this case is 36th reported case in Japan. 相似文献
28.
Upon autopsy of mice injected with the crown-of-thorns starfish (Acanthaster planci) lethal factor, a change in color of the liver, swelling of the gall bladder and jaundice were observed. After administration of the lethal factor into mice, activities of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH), acid phosphatase (ACP) and alkaline phosphatase (ALP) were significantly elevated in serum. Hepatic ALP also increased markedly but hepatic GOT, GPT and ACP showed a tendency to decrease. Activity of hepatic LDH first decreased and then returned to control level. Histopathological studies showed that severe degenerative changes such as enlargement and necrosis of hepatocytes were caused in the mouse liver by the lethal factor. These results strongly suggested that the A. planci lethal factor is a potent hepatotoxin. 相似文献
29.
Kohei Hashizume Hideo Kawarasaki Tadashi Iwanaka Yutaka Kanamori Kiyoshi Tanaka Tadahito Utsuki Hiroaki Komuro Kaoru Uno 《Surgery today》1993,23(4):293-297
It has been well documented that piriform sinus fistulae often cause suppurative thyroditis; however, when a piriform sinus fistula does not present this symptom, making a correct diagnosis is very difficult. We have experienced 11 cases of a piriform sinus fistula. The conventional operational approach was performed in the initial eight patients, among which there were four recurrences in two patients. Therefore, a new operational approach was introduced for the three most recent cases and one recurrent case. First, the existence of the internal orifice of the fistula is confirmed with a laryngoscope, after which a transverse incision on the neck is made and the abscess dissected. The side wall of the piriform sinus is then opened with the help of a laryngoscope and the bottom part of the mucosa of the sinus transected with the internal orifice of the fistula, after which the fistula is removed en bloc with the bottom part of the sinus and abscess cavity. Using this operation, we experienced no complications and there has been no recurrence so far.This paper was presented at the 23rd Annual Meeting of Pacific Association of Pediatric Surgeons, June 1990 in Kona, Hawaii. 相似文献
30.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献