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21.
ABSTRACT Embryotoxicity and teratogenicity of cadmium (Cd) and modulation of its effects by N-acetyl-L-cysteine (NAC) were evaluated in mice. Pregnant ICR mice were intraperitoneally injected with 3.5 mg/kg of CdCl2 on day 10 or 11 of gestation (vaginal plug = day 0). Pregnant mice were pretreated with 160 mg/kg of NAC intravenously 2 hours before dosing with CdCl2 . Pregnant mice were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations, cleft palate and abnormal palatal rugae. There was little difference in body weight gain of dams during the gestation period in the groups treated with NAC plus Cd as compared with the groups treated with Cd alone. Pretreatment with 160 mg/kg of NAC decreased the fetal mortality, incidence of cleft palate and abnormal palatal rugae induced by Cd on day 11. On day 10, pretreatment with NAC decreased the incidence of Cd induced abnormal palatal rugae. These results clearly indicate that NAC exerts protective effects against embryotoxicity and teratogenicity of Cd. 相似文献
22.
Yoichi Kikuchi Taku Sakurada Masato Suzuki Tomoyasu Hirano Katsuyuki Kusajima 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(8):375-378
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because
of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial
treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need
of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment
of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case
of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels
coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass. 相似文献
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25.
Masato Nakajima Koji Tsuchiya Yoshihiro Honda Hiroshi Koshiyama Tatsuho Kobayashi 《General thoracic and cardiovascular surgery》2009,57(12):654-656
Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical
case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus
in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully,
and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up. 相似文献
26.
Kohsuke Sasaki Daniel Pinkel Masato Tsukahara Ichiro Murano Joe W Gray 《Pathology international》1994,44(2):145-150
A human chromosomal translocation t(8;9) was detected using two-color fluorescence in situ hybridization with probes capable of staining the entire lengths of each of these chromosomes. The chromosome 8 probe was labeled with biotin and detected with Texas red, while the chromosome 9 probe was labeled with AAF and detected with FITC . In normal metaphase spreads, two metaphases from the proband, two red, one green and one part red and part green derivative chromosome were seen. The bicolor chromosome corresponded to translocation of a chromosome 8 segment to the distal part of the q region of one chromosome 9, as originally indicated by banding analysis. In interphase nuclei of the proband, four domains with bright fluorescence were recognized in many nuclei. Two were red, one was green, and the fourth had portions of both colors, indicating the presence of the translocation. 相似文献
27.
We report an 18-year-old boy with occipital horn syndrome and we review the 20 cases previously published with this syndrome. The distinctive features common to all patients were unusual facial appearance, skeletal abnormalities, chronic diarrhea and genitourinary abnormalities. The skeletal abnormalities included occipital horns, short, broad clavicles, deformed radii, ulnae, and humeri, narrowing of the rib cage, undercalci-fied long bones with thin cortical walls and coxa valga. Occipital horn syndrome is inherited in an X-linked recessive fashion. Our analysis indicates that occipital horn syndrome is associated with a recognizable characteristic phenotype. 相似文献
28.
Masakazu Yamagata Kimiko Kumano Masato Ueda 《Journal of the European Academy of Dermatology and Venereology》1997,9(3):256-258
Pyoderma gangrenosum is a rare, chronic, inflammatory ulcerative skin disease of unknown etiology and pathogenesis. It is often associated with systemic disease. We describe a patient with pyoderma gangrenosum associated with ulcerative colitis and aseptic abscesses of the subcutis and spleen, which have been rarely reported previously. These manifestations were cleared by combined therapy with minocycline hydrochloride and diaphenylsulfone. 相似文献
29.
Masato YASUI Hiroyuki TANAKA Toshiyuki ITO Yoshiki SEINO 《Nephrology (Carlton, Vic.)》1997,3(5):339-346
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor. 相似文献
30.
Yukiya Hashimoto Toshiko Koue Yuko Otsuki Masato Yasuhara Ryohei Hori Ken-ichi Inui 《Journal of pharmacokinetics and pharmacodynamics》1995,23(2):205-216
A simulation study was conducted to compare the cost and performance of various models for population analysis of the steady
state pharmacokinetic data arising from a one-compartment model with Michaelis-Menten elimination. The usual Michaelis-Menten
model (MM) and its variants provide no estimate of the volume of distribution, and generally give poor estimates of the maximal
elimination rate and the Michaelis-Menten constant. The exact solution to the Michaelis-Menten differential equation (TRUE)
requires a precise analysis method designed for estimation of population pharmacokinetic parameters (the first-order conditional
estimation method) and also considerable computational time to estimate population mean parameters accurately. The one-compartment
model with dose-dependent clearance (DDCL), in conjunction with the first-order conditional estimation or Laplacian method,
ran approximately 20-fold faster than TRUE and gave accurate population mean parameters for a drug having a long biological
half-life relative to the dosing interval. These findings suggest that the well-known MM and its variants should be used carefully
for the analysis of blood concentrations of a drug with Michaelis-Menten elimination kinetics, and that TRUE, in conjunction
with a precise analysis method, should be considered for estimating population pharmacokinetic parameters. In addition, DDCL
is a promising alternative to TRUE with respect to computation time, when the dosing interval is short relative to the biological
half-life of a drug.
This work was supported in part by the Epilepsy Research Foundation, the Nakatomi Foundation, and a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science, and Culture of Japan. 相似文献