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71.
72.
SeveralChlorellavirus CVK2 proteins had chitosanase and/or chitinase activities. A gene coding for an ORF of 328 amino acids (aa) with a predicted molecular mass of 36,769 Da was cloned from the viral genome. The predicted amino acid sequence of an N′-portion (174 aa) of this gene product (vChta-1) showed 22 to 25% identity with various bacterial chitosanases. A glutathioneS-transferase (GST)–vChta-1 fusion protein had strong chitosanase activity. Western blot analysis with antisera raised against the vChta-1 protein identified two proteins of 37 and 65 kDa in virus-infectedChlorellacells beginning at 240 min postinfection and continuing until cell lysis. The larger protein was packaged in the virion, while the smaller one remained in the cell lysate. Both chitosanase proteins were produced from the single gene,vChta-1,by a mechanism of alternative gene expression. 相似文献
73.
X Renming K Ishihara M Sasa H Ujihara T Momiyama Y Fujita N Todo T Serikawa J Yamada S Takaori 《European journal of pharmacology》1992,223(2-3):185-192
The effects of CNK-602A (N-[(6-methyl-5-oxo-3-thiomorpholinyl) carbonyl]-L-histidyl-L-prolinamide), a novel thyrotropin-releasing hormone related analog, were investigated on absence-like seizure and tonic convulsion in the spontaneously epileptic rat (SER), which is a genetically defined double-mutant. When CNK-602A of 0.2-1 mg/kg was given intravenously to the animal, there were no changes in the background EEG except for an increase in low-voltage fast waves concomitant with behavioral alertness. However, CNK-602A suppressed absence-like seizure and tonic convulsion in a dose-dependent manner for over 1 h. These antiepileptic effects of CNK-602A on both seizures were antagonized by pretreatment with haloperidol (1 mg/kg, i.p.). It was found, using a brain in vivo microdialysis method, that CNK-602A at a dose of 1 mg/kg, which inhibits the seizures, increased the release of dopamine in the caudate nucleus. These results suggest that CNK-602A inhibits the seizures of SER in a similar manner to thyrotropin-releasing hormone (TRH), probably by increasing the release of dopamine in the central nervous system. In addition, the antiepileptic effects of CNK-602A were more potent and lasted longer than those of TRH. 相似文献
74.
M. Ito K. Hayashi Y. Ishida M. Uetani M. Yamada M. Ohki T. Nakamura 《Calcified tissue international》1997,60(1):11-15
For several different bone mineral measurements and various skeletal sites, we compared capability to discriminate between
women in various age decades with and without spinal fracture, and attempted to identify the most effective cutoff level in
discrimination of spinal fracture. The subjects were 88 women aged 50–59 years (including 32 with fracture), 95 women aged
60–69 years (including 54 with fracture), and 34 women aged 70–79 years (including 18 with fracture). Spinal trabecular and
cortical bone mineral density (BMD) were measured using quantitative computed tomography (CT), and spinal, radial (ultra-distal,
10% distal and 33% distal), and calcaneal BMD were measured by dual X-ray absorptiometry. These BMD values were obtained in
each subject on the same day. Three statistical techniques—Student's t-test, the logistic regression analysis, and the receiver operating characteristics (ROC) analysis— were applied and accuracy
was calculated using the various cutoff values. The capability to discriminate between women with and those without fracture
using these BMD values was different among the three age groups. In women aged 50–59 and 60–69 years, all measurements showed
good capabilities for discriminating women with fracture. In women aged 70–79 years, these measurements showed lower capability
than in those aged 50–59 and 60–69 years, but among them, the calcaneal and ultradistal radial BMD showed relatively good
capability. The 10% and 33% distal radial BMD values were not useful in the detection of the high risk women with fracture.
The cutoff BMD values for discrimination of women with fracture varied according to the sites and methods of measurement.
For each specific age group, the most suitable measurement methods and the appropriate skeletal sites should be considered,
and the effective cutoff values to discriminate those with fracture may differ according to the measurement methods, the skeletal
sites examined, and age.
Received: 5 February 1996 / Accepted: 18 June 1996 相似文献
75.
We have prepared a new material for embolisation: ethylene vinylacetate copolymer dissolved in polyvinyl alcohol. When in contact with blood, polyvinyl alcohol rapidly becomes a soft gel, which is accompanied by wedging of the ethylene vinylacetate copolymer. We analysed the histopathology of intra-arterial microemboli in rats, after intracarotid injection of this material. We confirmed that it was applicable to embolisation for neurosurgical treatment. 相似文献
76.
A 37 year old nurse with the rare combination of idiopathic thrombocytopenic purpura (ITP), Hashimoto's thyroiditis and rheumatoid arthritis (RA) was reported. In 1983, six years before her final diagnosis was made, she presented with purpura over her extremities and swelling of the cervical lymph nodes. Laboratory findings showed the following: platelet count 15 x 10(3)/microliters, the number of megakaryocyte without platelet production in bone marrow was increased, platelet life span (T1/2) 11 min. A diagnosis of ITP was made. In 1984 goiter was noticed. Laboratory data were as follows: T3 502ng/ml, T4 27.0 micrograms/dl, thyroid test x 1,600, microsome test x 409,600. She was diagnosed as having ITP and Hashimotoxicosis. She had been uneventful except temporary hyperthyroidism until 1989 when she developed morning stiffness, polyarthralgia, swelling of PIP joints, contracture of elbow joints and hallux valgus. Laboratory investigation were reported as follows. ESR 111mm/h, platelet count 31 x 10(3)/microliters, platelet associated IgG 800ng/10(7) pl, antinuclear antibody x 2,560, rheumatoid factor 1+, microsome test x 1,600, anti-DNA antibody 3U/ml. Anti-Sm antibody and anti-RNP antibody were not detected. The LE cell test was negative. Schirmer test and sialography were interpreted as normal. These findings confirmed the diagnosis of RA in addition to ITP and Hashimoto's thyroiditis. The combination of RA, ITP and Hashimoto's thyroiditis is extremely rare although these three disorders are classified as autoimmune disease. 相似文献
77.
Atsushi Ota Nobuyasu Kano Hiroshi Kusanagi Shigetoshi Yamada Arty Garg 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):172-175
Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely. 相似文献
78.
Yuzo Kodaira Tetsuo Shibuya Koushi Matsumoto Kiichiro Uchiyama Toshihiro Tenjin Nobutaka Yamada Shigeo Tanaka 《Surgery today》1997,27(8):745-748
A 66-year-old man died of massive gastrointestinal hemorrhage caused by a fistula between the third portion of the duodenum
and the abdominal aorta. An autopsy revealed that duodenal tuberculosis had resulted in the development of a fistula into
the aorta with no pathological changes, and no active pulmonary tuberculosis was found. Duodenal tuberculosis and primary
aortoduodenal fistula (ADF) without an aneurysm are both extremely rare. Thus, we report herein a unique case of primary aortoduodenal
fistula without an abdominal aortic aneurysm, but associated with duodenal tuberculosis, and review the current literature. 相似文献
79.
Hironari Takaishi Osamu Nemoto Masanobu Shiota Toshiyuki Kikuchi Harumoto Yamada Masaaki Yamagishi Yutaka Yabe 《Journal of orthopaedic research》1997,15(4):528-538
To clarify phenotypic alterations of intervertebral disc cells during the repair process, we cloned partial type-II collagen cDNA from rabbits and analyzed the level of expression of type-II collagen mRNA in disc degeneration. An animal model was created by surgical denucleation of rabbit intervertebral discs through, an extraperitoneal approach. Eight animals each from an experimental and a control group were killed at 2, 4, 8, or 16 weeks postoperatively, and the disc samples were used for this study. Round chondrorcyte-like cells that filled the herniated space showed intense signal of type-II collagen mRNA and significant pericellular immunostaining of type-II collagen but no clear staining of type-I collagen. Northern. blot analysis revealed that the expression of type-II collagen mRNA of the repair disc cells was transiently increased at 4 weeks postoperatively. The cells were able to change their morphology in response to mechanical stimulation by surgical denucleation and to induce a significant increase in the gene expression of type-II collagen at an early phase of disc degeneration. The present results indicate the transient enhancement of repair activity in the degenerative process of injured fibrocartilage. 相似文献
80.
T Iwama H Yamada T Andoh N Sakai S Era M Sogami K Kuwata H Watari 《Magnetic resonance in medicine》1992,25(1):78-84
The spin-lattice relaxation time (T1) of water protons and the cross-relaxation time (TIS) between irradiated protein protons and observed water protons were measured in order to study water-macromolecular interactions in ischemic rat brain tissues. Tissues were obtained by bilateral common carotid artery occlusion from stroke-prone spontaneously hypertensive rats. Water, Na, and K contents were measured in ischemic brain tissue at the same time. Water and Na content increased while the TIS value and K content decreased following ischemic insults. The T1 value did not change until 180 min after ischemia had been induced. Changes in the TIS value occurred earlier than changes observed for the T1 value, water, and electrolyte contents. Results indicate that the value of TIS may be useful for detecting cerebral ischemia and that the physical structure of water-macromolecular interaction may be altered soon after ischemic onset in brain tissue. 相似文献