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81.
82.
Purine phosphoribosyltransferase activities in normal and experimental hyperkeratotic epidermis of guinea pig skin were demonstrated quantitatively by a new microassay method. The ratio of HGPRTase with hypoxanthine as a substrate to APRTase activity in normal and hyperkeratotic epidermis was found to be 0.94 and 0.60, respectively. The HGPRTase and APRTase activities expressed as micromoles per gram wet weight per min. were increased in experimental hyperkeratotic epidermis and it is suggested that the salvage pathway for purine nucleotide biosynthesis is activated in experimental hyperkeratotic epidermis. The pH optimum of these enzymes and their stability in the frozen state were also demonstrated. 相似文献
83.
Haemodynamic effects of the crude venom from nematocysts of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) in anaesthetized rabbits. 总被引:1,自引:0,他引:1
Tomoyuki Koyama Katsuhiko Noguchi Toshihiro Matsuzaki Mayuko Sakanashi Junko Nakasone Kanako Miyagi Makiko Sakanashi Matao Sakanashi 《Toxicon》2003,41(5):621-631
Haemodynamic effects of saline-extracted venom from nematocysts isolated from tentacles of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) were investigated. In anaesthetized rabbits, i.v. injections of the venom produced hypotension following a transient hypertension. Mean femoral arterial blood flow markedly decreased immediately after the injection and femoral vascular resistance increased. Left ventricular dP/dt remarkably decreased after a transient and small increase, and heart rate decreased. Left ventricular end-diastolic pressure markedly elevated. All of the above changes by 0.2-5 microg/kg of the venom expressed as the amount of protein were seen dose-dependently and occurred without tachyphylaxis. In five of seven animals received an injection of the venom at 10 microg/kg, irreversible cardiac arrest occurred. Changes produced by 1 or 2 microg/kg of the venom were significantly attenuated either by heating the venom at 40 degrees C for 10min or by pretreatment with diltiazem. These results indicate that the venom from Habu-kurage has both vasoconstrictor and cardiodepressive effects, and suggest that these thermolabile actions may be due partly to activation of voltage-dependent calcium channels and probably subsequent calcium-overload. 相似文献
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86.
Junko Miyamoto Hiroshi Asanuma Hideo Nakai Tomonobu Hasegawa Hajime Nawata Yukihiro Hasegawa 《Clinical Pediatric Endocrinology》2006,15(4):151-162
The prevalence of abnormalities in androgen receptor gene (AR) among patients with
ambiguous genitalia is unknown. Moreover, endocrinological data from prepubertal patients
with AR mutation are very limited. Thus, the aim of this study was to examine the
prevalence of abnormalities in AR among patients with both ambiguous genitalia, which was
defined as a combination of two or more genital abnormalities (i.e. hypospadias,
microphallus (penile length < 25 mm), hypoplastic scrotum, bifid scrotum, undescended
testis) in this study, and normal to elevated T levels. We also compared the
endocrinological data of prepubertal patients with AR mutation and ambiguous genitalia
with that of those without the AR mutation. We screened 26 Japanese prepubertal 46,XY
patients (five from three families were included) with both ambiguous genitalia and normal
to elevated T levels. Mutations in AR were found in three (two of the three were related).
Among the 23 patients without mutation in AR, the steroid 5-alpha-reductase 2 gene
(SRD5A2) was also examined in eight patients with elevated T/dehydrotestosterone ratio
after the hCG (>10) or with undervirilized family members. No mutation in SRD5A2 was
found. Characteristics of the three patients with mutation in AR were compared with the 23
patients without mutation. In two patients, basal T levels (0.3, 0.2 ng/ml) and peak T
levels after the hCG tests (8.3, 8.5 ng/ml) tended to be higher, and the peak LH/ peak FSH
ratios after the GnRH tests (4.6, 4.0) were higher than in patients without mutation, at
the ages of 1 yr and 9 mo and 3 yr and 8 mo, respectively. In conclusion, an abnormality
in either AR or SRD5A2 was not common among patients with ambiguous genitalia and normal
testosterone secretion. Elevated peak LH/peak FSH ratio (≥4) after the GnRH test in
addition to detectable basal T levels and elevated peak T levels after the hCG test may
infer AR abnormality in prepubertal patients with ambiguous genitalia at the age of one
and over, although further study is needed, because our data were limited. 相似文献
87.
88.
Sakurada T Kikuchi Y Obata H Suzuki T Hirano T Kusajima K 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(13):1073-1075
We report twelve cases of minimally invasive coronary artery bypass grafting via small laparotomy using right gastroepiploic artery (RGEA) to the right coronary artery. Seven patients were operated on without partial sternotomy (N group), and lower partial sternotomy with Octopus 2 stabilization system was used in five of the cases (P group). Postoperative Doppler echographic imaging or angiographic study showed all RGEA grafts were functioning well in P group. However, graft occlusion was observed in two of the cases in N group. Inferior partial sternotomy combined with Octopus 2 stabilization system produce a clear surgical view, which avoids of both full-sternotomy and cardiopulmonary bypass. This method might be useful especially for reoperation. 相似文献
89.
Kikuchi Y Sakurada T Suzuki T Obata H Kusajima K 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(4):295-300
From April, 1999 to November, 1999, 8 patients underwent the aortic valve replacement using Medtronic Freestyle aortic root bioprosthesis. Mean age was 67.8 years old. Aortic valve etiology was as follows, AS: 1 case, AR: 2 cases, ASR: 3 cases, IE: 1 case, mechanical valve malfunction due to subvalvular pannus: 1 case. The implanted valve size was 25: 2 cases, 23: 3 cases, 21: 1 cases, 19: 2 cases. Surgical technique was subcoronary: 7 cases, full-root: 1 case. Post-op 2D-echo revealed tribial aortic valve incompetence in two cases because of size discrepancy between the aortic annulus and the ascending aorta. Pacemaker implantation was needed in 1 case because of the complete A-V block. In comparison with 5 cases of aortic valve replacement with Hancock II performed in same period, there were no significant differences about the implanted valve size and mean systolic pressure gradient, but the effective orifice area in Freestyle cases was significantly larger than Hancock II cases. 相似文献
90.