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51.
Shohei Takeda Yutaka Inada Yoshiki Ozawa Narue Nakamizo Teruaki Tomaru 《Journal of anesthesia》1995,9(2):176-181
The cardiovascular responses to an infusion of KRN2391, a potassium channel opener, was studied in halothane-anesthetized
dogs. Intravenous administration of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 for 60 min produced dose-dependent decreases in mean arterial pressure (MAP) and systemic vascular resistance (SVR) associated
with dose-dependent increases in the cardiac index (CI) and stroke volume index (SVI) but was not accompanied by an increase
in heart rate (HR). The maximum decrease in MAP during the infusion of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 was −13±7% (P<0.01) and −37±10% (P<0.01), respectively. The maximum reduction in SVR after 1.0 and 5.0 μg·kg−1·min−1 was −20±11% (P<0.01) and −60±16% (P<0.01), respectively. A KRN2391 infusion of 1.0 and 5.0 μg·kg−1·min−1 increased Cl a maximum of 11±13% (P<0.05) and 65±33% (P<0.01), respectively. KRN2391 1.0 μg·kg−1·min−1 showed a tendency to increase SVI but this change was not significant, KRN2391 5.0 μg·kg−1·min−1, however, produced a significant increase in SVI. The present results demonstrate that the decrease in MAP and the increases
in CI and SVI caused by KRN2391 are due to a reduction in the afterload. Therefore, we conclude that these cardiovascular
profiles of KRN2391 may be benificial in perioperative uses including the control of systemic blood pressure and the treatment
of hypertension during halothane anesthesia in clinical practice. 相似文献
52.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414
53.
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
54.
Sofikitis N; Miyagawa I; Yamamoto Y; Loutradis D; Mantzavinos T; Tarlatzis V 《Human reproduction update》1998,4(3):197-212
This review refers to the evolution of ooplasmic injectionsof round spermatid nuclei ROSNI) or intact round spermatidsROSI). Conclusions from their preliminary application in thehamster, rabbit, mouse and human are discussed. Criteria foridentification of round spermatids and guidelines/quality controlfor application of ROSNI/ROSI techniques are emphasized. Althoughall the animal offspring and the human newborns delivered afterROSNI/ROSI are healthy additional research efforts are necessaryto confirm the safety of these procedures and improve theiroutcome 相似文献
55.
Kozo Yamada Seiji Hayasaka Yukari Yamamoto Tomoichi Setogawa 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1990,228(1):1-4
We examined 62 patients with acute herpes zoster involving the trigeminal nerve; 13 had eruptions only and 49 (51 eyes) had
eruptions with ocular complications. Bilateral involvement was found in two patients. The frequency of the disease appeared
to increase with age, and the disease was least active in November. Patients with eruptions only demonstrated affected areas
along the first, second, and/or third divisions of the trigeminal nerve. Ocular complications occurred in patients who had
eruptions along the first and/or second divisions of the nerve, and they were usually noted in patients with eruptions on
the tip and one side of the node. The ocular complications and associated systemic conditions varied. 相似文献
56.
H Mukaida T Yamamoto T Hirai M Toi T Nakamura T Wada Y Yamashita K Kawano M Niimoto 《The Japanese journal of surgery》1990,20(3):275-282
The expression of human epidermal growth factor (hEGF) was examined immunohistochemically in 86 esophageal cancer lesions, comprising 67 primary tumors and 19 metastatic lymph nodes. In the normal esophagus, the parabasal and intermediate cell layers showed a weak expression of hEGF, however, hEGF-positive tumor cells were detected in 62 (92.5 per cent) of the 67 primary esophageal carcinomas and in 18 (94.7 per cent) of the 19 metastatic lymph nodes. In this study, the immunoreactivity of hEGF was classified into 4 grades according to the number of stained tumor cells. A significant correlation was observed between the histologic type and the grade of hEGF immunoreactivity (Chi-square test, p less than 0.01). hEGF immunoreactivity in well differentiated squamous cell carcinomas was significantly higher than in other squamous cell carcinomas, although there were no correlations between other pathological findings and hEGF immunoreactivity. Patients with hEGF immunoreactivities of grades II or III had much worse prognoses than those with grades 0 or I (p less than 0.05). In 22 esophageal carcinomas and 10 normal esophageal mucosae, EGF receptor (EGFR) contents were measured by the competitive binding assay. The average EGFR content (101.3 +/- 35.7 fmol/mg protein, mean +/- SE) of the esophageal carcinomas was significantly higher than that (5.3 +/- 1.2) of the normal esophageal mucosae (p less than 0.05). Moreover, in hEGF negative tumors, EGFR contents were lower than in hEGF positive tumors. These results suggest that hEGF and EGFR show increased production in squamous cell carcinomas and could to be useful prognostic factors in patients with esophageal cancer. 相似文献
57.
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
58.
Shoji Matsushima Yuko Sakai Yoshiki Hira Masamichi Kato Tsukasa Shigemitsu Yoichi Shiga 《Journal of pineal research》1993,14(3):145-150
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat. 相似文献
59.
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
60.
Kohji Matsushita Kazuo Kitagawa Tomohiro Matsuyama Toshiho Ohtsuki Akihiko Taguchi Kenji Mandai Takuma Mabuchi Yoshiki Yagita Takehiko Yanagihara Masayasu Matsumoto 《Brain research》1996,743(1-2)
The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca2+-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n=6) or twice at 24 and 48 h before ischemia (subacute group; n=14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity. 相似文献