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We used the laser flowmeter to measure and compare the effect of nitroglycerin (TNG), trimetaphan (TMP) and prostaglandin E1 (PGE1) on the blood flow of operating field during hypotension induced by each drug. The study was done in 33 patients (TNG:13, TMP:13 and PGE1:7) anesthetized with modified NLA who underwent radical mastectomy. We put the probe of the laser flowmeter on the skin of the opposite breast to the operating field and measured the skin blood flow change. Measurements were made before and during hypotension induced by each drug. TMP-induced hypotension decreased blood flow significantly (P less than 0.05), but TNG and PGE1 had no significant effect. Intraoperative blood losses of TNG and PGE1 group were not significantly larger than that of TMP group. From this study we conclude that TNG, TMP and PGE1 can dry the operating field and decrease intraoperative blood loss similarly. Therefore we should choose the drugs to induce hypotension considering the effect of the drug on blood flow of the important organs and each patient's complications.  相似文献   
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The defecation reflex is composed of rectal distension-evoked rectal (R-R) reflex contractions and synchronous internal anal sphincter (R-IAS) reflex relaxations in guinea pigs. These R-R and R-IAS reflexes are controlled via extrinsic sacral excitatory nerve pathway (pelvic nerves), lumbar inhibitory nerve pathways (colonic nerves) and by intrinsic cholinergic excitatory and nitrergic inhibitory nerve pathways. The effect of mosapride (a prokinetic benzamide) on the intrinsic reflexes, mediated via enteric 5-HT(4) receptors, was evaluated by measuring the mechanical activity of the rectum and IAS in anesthetized guinea pigs using an intrinsic R-R and R-IAS reflex model resulting from chronic (two to nine days) lumbosacral denervation (PITH). In this model, the myenteric plexus remains undamaged and the distribution of myenteric and intramuscular interstitial cells of Cajal is unchanged. Although R-R and R-IAS reflex patterns markedly changed, the reflex indices (reflex pressure or force curve-time integral) of both the R-R contractions and the synchronous R-IAS relaxations were unchanged. The frequency of the spontaneous R and IAS motility was also unchanged. Mosapride (0.1-1.0 mg/kg) dose-dependently increased both intrinsic R-R (maximum: 1.82) and R-IAS reflex indices (maximum: 2.76) from that of the control (1.0) 6-9 days following chronic PITH. The dose-response curve was similar to that in the intact guinea pig, and had shifted to the left from that in the guinea pig after acute PITH. A specific 5-HT(4) receptor antagonist, GR 113808 (1.0 mg/kg), decreased both reflex indices by approximately 50% and antagonized the effect of mosapride 1.0 mg/kg. This was quite different from the result in the intact guinea pig where GR 113808 (1.0 mg/kg) did not affect either of the reflex indices. The present results indicate that mosapride enhanced the intrinsic R-R and R-IAS reflexes and functionally compensated for the deprivation of extrinsic innervation. The actions of mosapride were mediated through endogenously active, intrinsic 5-HT(4) receptors which may be post-synaptically located in the myenteric plexus of the anorectum.  相似文献   
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We have previously reported that continuous infusion of dobutamine into the coronary artery induces positive inotropic effects but induces no detrimental effects in cross-circulated, excised normal rat hearts and even in Ca2+ overload-induced contractile failing rat hearts. However, we hypothesized that some detrimental effects on left ventricular (LV) function are induced after continuous dobutamine infusion and the following clearance of blood dobutamine, as is the case after beta-adrenergic receptor stimulation. To test this hypothesis, we investigated LV mechanical work and energetics in the same type of preparations that underwent continuous dobutamine infusion and clearance of blood dobutamine. We found that both mean end-systolic pressure and systolic pressure-volume area (PVA; a measure of total mechanical energy per beat) at midrange LV volume were significantly (P < 0.01) decreased. The mean myocardial oxygen consumption per beat intercept, which is composed of for the total Ca2+ handling in excitation-contraction coupling and basal metabolism, of the and PVA linear relation was also significantly (P < 0.05) decreased (n=8). The mean slope of the linear relation was unchanged in such hearts. Post-dobutamine basal metabolism was unchanged (n = 5 of the 8 hearts). The moderate proteolysis of a cytoskeleton protein, alpha-fodrin was identified (n = 7 of the 8 hearts with the decreased intercept), after clearance of blood dobutamine. In agreement with our hypothesis, the detrimental effect of the post-beta-adrenergic receptor stimulation was induced by a moderate concentration of dobutamine; we found systolic dysfunction due to the impairment of Ca2+ handling in excitation-contraction coupling in the rat LV and proteolysis of a cytoskeleton protein, alpha-fodrin.  相似文献   
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We report on a 6-year-old boy with de novo 46, XY, del(3)(q12q23) and bilateral blepharo-phimosis, ptosis, epicanthus inversus, in addition to multiple other anomalies. Since 4 previously reported cases of interstitial deletion of 3q involving 3q23 band are clinically similar, we propose this blepharophimosis sequence due to 3q23 deletion as a further “contiguous gene syndrome”.  相似文献   
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Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
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Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%. The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were made through this experimental period at different stages. The observations were also carried out on the mice administered with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe increased while urine Ca decreased in the phosphate-treated groups. The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller; in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries, proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly advanced aspect of the changes which are more pronounced with increasing dose and age. These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months) produced effects stronger than those to younger subjects administered for a long term (10.5 months). The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was supposed that these effects were caused by phosphate radicals. An erratum to this article is available at .  相似文献   
10.
IntroductionThe purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation.MethodsA prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15–25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed.ResultsThe optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0–3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05).ConclusionsWe concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation.  相似文献   
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