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491.
ABSTRACT Our previous study suggested that the teratogenic effect of methamphetamine (MAMP) may be influenced by the housing conditions under which drug-treated pregnant animals were kept (Yamamoto et al., 1992). In the present study, pregnant mice were housed individually and their teratological data were compared with those obtained in the previous study where pregnant females were housed in aggregated groups. Pregnant mice were individually housed in a plastic cage and they received i.p. 11, 13, 15, 17, 19, or 21 mg/kg MAMP hydrochloride on day 8 of pregnancy (plug day = day 0). All the pregnant females treated with MAMP survived to term; this was in contrast to the high mortality rate of the animals which were treated with MAMP and kept in groups. No significant difference in the number of implantations and the resorption rate was noted between the control and treated groups. Malformed fetuses (externally, skeletally or viscerally) were encountered in the MAMP-treated groups at prevalence rates of 0.6–3.2%, but the rates were not significantly different from the control value. The incidence of malformations was significantly lower in the groups kept in solitary conditions than in aggregated groups examined previously. The present study showed that crowding of pregnant females can potentiate the teratogenic effects of MAMP in mice. Some maternal physiological alterations caused by crowded environment such as stress-induced glucocorticoid secretion and maternal hyperthermia may be responsible for the potentiated teratogenicity of MAMP in crowded housing conditions. 相似文献
492.
J. YAMAMOTO U. OKAMOTO S. KOJIMA S. MORITA K. FUJII 《International journal of laboratory hematology》1982,4(2):117-130
Summary A method for separate measurement of the amounts of the native form and partially degraded form of plasminogen and plasmin in human circulating blood was devised based on their different mobilities on disc polyacrylamide gel electrophoresis. The relative amounts in the circulating blood as estimated by the method were as follows: 78.5% native form, 6.1% partially degraded form and 15.5% plasmin, in the resting state of healthy adults. The partially degraded form increased to about 50% after strenuous exercise load. The present study showed that relatively large amounts of the partially degraded form can be produced in the circulating blood, even though abundant plasmin inhibitors exist there. These data suggest that the partially degraded form may play an important role in thrombolysis in vivo. 相似文献
493.
Exocrine Pancreatic Function Test by a Synthetic Peptide 总被引:1,自引:0,他引:1
HIDEO HARADA M.D. KUNIKI MISHIMA M.D. TETSUMASA SHUNDO M.D. NIHEI YAMAMOTO M.D. TETSURO SASAKI M.D. TATSURU HINOFUJI M.D. TENMEI HAYASHI M.D. YOSHITOMO UCHIDA M.D. IKURO KIMURA M.D. 《The American journal of gastroenterology》1979,71(1):45-52
A new synthetic substance, N-Benzoyl-L-tyrosyl-p-aminobenzoic acid, is specially cleaved by pancreatic chymotrypsin after oral administration and the released p-aminobenzoic acid (P.A.B.A.) is absorbed and excreted in the urine. The P.A.B.A. recovery in the urine was examined to evaluate its diagnostic value as an exocrine pancreatic function test. The data permit the following conclusions: 1. There is a significant correlation between this test and maximal bicarbonate concentration, amylase output and volume of P.Z./C.C.K. secretin test. 2. More than one-half to two-thirds proximal or one-third distal of the pancreas must be removed before one can expect an abnormal result in this test. 3. This is a simple and useful test to detect exocrine pancreatic insufficiency of more than moderate degree but normal results may be obtained in minimal to mild exocrine pancreatic insufficiency. Only six of 11 cases (54.5%) with one abnormal factor of P-S test showed decreased P.A.B.A. recpvery, whereas 22 of 23 cases (95.7%) with two or three abnormal factors of P-S test showed decreased or borderline P.A.B.A. recovery. 相似文献
494.
495.
YOKO S ADACHI YUICHI ADACHI TOSHIKO ITAZAWA JUNKO YAMAMOTO GYOKEI MURAKAMI TOSHIO MIYAWAKI 《Pediatrics international》2006,48(1):62-65
BACKGROUND: Although current guidelines recommend the pressurized metered-dose inhaler with a spacer for preschool children with asthma, dry powder inhalers (DPI) may be a valuable treatment alternative. METHODS: To evaluate the ability of preschool children to inhale through DPI, peak inspiratory flow rates (PIFR) of 57 healthy children aged 3-6 years were measured with In-Check Meter after practising with an instructor. Two different calibrated resistances were attached to the Meter to mimic the internal resistance of each inhaler; Diskus and Turbuhaler. RESULTS: The ability of children to generate adequate inspiratory flow increased with age. The percentages of the 3-, 4-, 5-, and 6-year-old children who were able to inhale reliably through the devices were 30% (3/10), 79.0% (15/19), 100% (16/16), and 100% (12/12), respectively. In these children, 100%, 93.3%, 100%, and 100% achieved an adequate PIFR for the Diskus (30 L/min). In contrast, 66.7%, 66.7%, 62.5%, and 91.7% generated an adequate PIFR for the Turbuhaler (60 L/min). CONCLUSIONS: The In-Check Meter is a useful device to assess the ability of preschool children to generate adequate PIFR for each inhaler. Most children aged > or =5 years could use DPI. 相似文献
496.
研究瑞巴派特经空肠、回肠和结肠黏膜的透过特性。制备大鼠不同区段肠黏膜样本,使用体外扩散池法,评价80 μmol·L-1瑞巴派特经空肠、回肠和结肠黏膜的经时吸收方向(M-S)和分泌方向(S-M)的透过量和透过系数(Papp),瑞巴派特在接受室中的浓度用HPLC法测定。结果表明,瑞巴派特经空肠和回肠的透过性高于结肠。比较M-S方向和S-M方向的透过性发现,药物在空肠和结肠经两个方向的透过性无显著差异,但经回肠透过时,分泌方向的透过性高于吸收方向的透过性(P<0.05)。瑞巴派特经大鼠肠黏膜的透过性存在区段差异。瑞巴派特可能不受肠黏膜P-糖蛋白转运体的调控。 相似文献
497.
E. YAMAMOTO K. INO T. YAMAMOTO† S. SUMIGAMA A. NAWA S. NOMURA & F. KIKKAWA 《International journal of gynecological cancer》2007,17(1):254-258
Nongestational pure choriocarcinoma of the ovary is a very rare germ cell tumor. Except in women before menarche, determination of the origin is very difficult without genetic analysis. We present a pure nongestational choriocarcinoma arising in the left ovary of a 19-year-old woman. Following surgery, pathologic findings of the tumor demonstrated pure choriocarcinoma without combination of other germ cell tumor elements. We confirmed its nongestational origin by DNA polymorphism analysis at 15 short tandem repeat loci. Multiple courses of chemotherapy with methotrexate, etoposide, and actinomycin-D were effective for this case. DNA polymorphism analysis is useful to determine genetic origin in pure choriocarcinoma of the ovary. 相似文献
498.
NOBUO TOSHIDA M.D. KENZO HIRAO M.D. NAOHITO YAMAMOTO M.D. MICHIO TANAKA M.D. FUMIO SUZUKI M.D. MITSUAKI ISOBE M.D. 《Journal of cardiovascular electrophysiology》2001,12(11):1256-1264
INTRODUCTION: A single ventricular echo beat frequently is induced in the dog heart by ventricular pacing, but it has not been investigated using a concomitant ablative technique. We studied the effects of ablating the anterior atrial input to the AV node on ventricular echo beats induced in the dog heart to evaluate their electrophysiologic characteristics, the anatomic reentrant circuit, and the retrograde AV nodal exits. METHODS AND RESULTS: In 20 dogs, an epicardial radiofrequency current was applied to the right anterior septum in an attempt to ablate the anterior input to the AV node. Ventricular programmed stimulation was performed to evaluate the ventricular echo beat and the retrograde AV nodal exit before and after ablation. The AV junction was examined with light microscopy. Seventeen dogs in which the PR interval was prolonged significantly from 108+/-17 msec to 153+/-19 msec (P < 0.001) were selected for ventricular echo evaluation; 3 dogs in which persistent second- or third-degree AV block was induced by ablation were excluded. Ventricular echo beats, which were induced in 13 of 17 dogs, were classified into the anterior type (n = 6) or posterior type (n = 7) according to the earliest atrial activation site during the echo beat. The retrograde AV nodal exit site showed anterior-exit only (n = 10), posterior-exit only (n = 2), and dual-exit (n = 5) patterns. After ablation, the anterior-type ventricular echo beat was noninducible in all 6 dogs, whereas the posterior-type ventricular echo beat was noninducible in only 3 of 7 dogs. In 17 dogs, VA conduction was not demonstrated after ablation in 3 dogs, all of which showed the anterior-exit only pattern. CONCLUSION: The effect of ablation on the ventricular echo beats and retrograde AV nodal exit site suggests multiplicity in their electrophysiologic and anatomic characteristics in the dog heart. 相似文献
499.
Late onset erythropoietic porphyria 总被引:4,自引:0,他引:4
Y. HORIGUCHI T. HORIO M. YAMAMOTO T. TANAKA Y. SEKI S. IMAMURA 《The British journal of dermatology》1989,121(2):255-262
A 51-year-old Japanese man and his 56-year-old sister of consanguineous parents had skin lesions with areas of dark-brown pigmentation and blisters with minimal trauma on sun-exposed skin which resembled those seen in porphyria cutanea tarda. Their fresh urine was wine-red in colour and fluoresced with ultraviolet light. The peripheral blood contained fluorocytes and porphyrin analysis of the red blood cells, urine and faeces of the patients revealed an increase of the isotype I of uro- and coproporphyrin and normal concentrations of delta-aminolaevulinate and porphobilinogen, suggesting the diagnosis of erythropoietic porphyria. No other members of this family had symptoms or biochemical findings suggestive of porphyria. We consider these two cases to be that of late onset erythropoietic porphyria. 相似文献
500.
HIDEYUKI TOZAKI TOMOKAZU ODORIBA TOMOYA ISEKI TOSHIO TANIGUCHI TAKUYA FUJITA MASAHIRO MURAKAMI SHOZO MURANISHI AKIRA YAMAMOTO 《The Journal of pharmacy and pharmacology》1998,50(8):913-920
The objective of this study was to examine the effects of protease inhibitors on the absorption of calcitonin from different regions of the intestine in rats. The absorption experiments were investigated by in-situ use of closed intestinal loops in rats and stability of calcitonin was examined in mucosal homogenates and intestinal fluids. The intestinal absorption of calcitonin was evaluated by measurement of its hypocalcaemic effect. No substantial hypocalcaemic response was observed when calcitonin was administered into the jejunum or colon. A slight hypocalcaemic effect was observed after administration of calcitonin into the ileum. Of the co-administered protease inhibitors, bacitracin (20 mM) strongly promoted calcitonin absorption from the jejunum, ileum and colon. A significant hypocalcaemic effect was also obtained after intestinal administration of calcitonin with soybean trypsin inhibitor (10mgmL?1), camostat mesylate (20mM) or aprotinin (2mgmL?1). In the stability experiment, bacitracin reduced the degradation of calcitonin in the different intestinal homogenates. Soybean trypsin inhibitor significantly reduced the degradation of calcitonin in the fluids of the small intestine. We also examined the different endopeptidases in gut luminal fluids and the different exopeptidases in gut mucosal homogenates of rats. The ranking order for the total endopeptidase activity of the intestinal fluids was jejunum > ileum > colon. That for total exopeptidase activity of the intestinal mucosa was jejunum > ileum > colon. These results suggest that endo- and exopeptidases might be responsible for the hydrolysis of calcitonin and that protease inhibitors might usefully improve absorption of calcitonin to the systemic circulation from the large intestine. 相似文献