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To elucidate the effects of teeth on muscle fibers in the tongue during the developmental process, we examined the expression of muscle contractile proteins and the genes for those proteins in normal mice and microphthalmic (mi/mi) mice with impaired tooth eruption. The mice were observed during the growth period, including weaning, which is when feeding movements undergo major changes. Expression of the myosin heavy chain (MyHC)-2a protein, whose contraction speed is relatively slow, disappeared after weaning in normal mice, while it remained in high concentrations even after weaning in mi/mi mice. The presence of MyHC-2a after weaning in mice with no tooth eruption was attributed to a compensation for lack of proper masticatory function and sucking-like movements, as MyHC-2a is necessary for these movements.  相似文献   
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We report on a Thai family with dominantly inherited malformation syndrome with upper limb anomalies, short stature, quadricuspid aortic valve, and minor craniofacial anomalies. The affected individuals comprised a mildly affected mother, a moderately affected daughter, and a most severely affected son. The daughter and son had short stature. The craniofacial abnormalities comprised frontal bossing, hypoplastic nasal bones, depressed nasal bridge, and broad nasal alae. The upper limb defects varies among the patients, ranging from radial ray defects in the mother through radial and ulnar ray defects with unilateral humeral hypoplasia in the daughter to radial ray defects with severe oligodactyly and bilateral humeral hypoplasia in the son. All patients in this family had hypoplasia of the shoulder girdle and resembled what is observed in many families with Holt‐Oram syndrome. Moreover, the son showed quadricuspid aortic valve with mild aortic regurgitation. However, the present family did not show any mutation of the TBX5 gene, a disease‐causing gene of Holt‐Oram syndrome. The present family deserves further investigation on other genes that play a role in the development of the upper limbs, particularly of radial rays. © 2002 Wiley‐Liss, Inc.  相似文献   
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We present surface anatomy scanning (SAS) image by weighted-summation technique using MRI images in herpes simplex encephalitis. Recently, SAS has been developed as a technique that visualizes brain surface structures. This patient was a 64-year-old male who suffered from aphasia and memory disturbance after herpes simplex encephalitis. He was transferred to our hospital for rehabilitation. Neuropsychological tests showed Wernicke's aphasia and memory impairment. SAS was performed for the purpose of analyzing these neuropsychological deficits, especially the Wernicke's aphasia. In SAS image, sulci were enhanced and gyri were easy to identify clearly. The affected structures disclosed low intensity areas in the entire left temporal lobe, including the superior temporal gyrus. It was clarified that the damage to the left superior temporal gyrus resulted in his Wernicke's aphasia. We think that SAS is very useful for cortical lesion analysis, not only in encephalitis but also in other disorders presenting higher brain dysfunctions.  相似文献   
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Endothelin, a 21-amino acid peptide produced by vascular endothelial cells, caused a sustained constriction of isolated large cerebral arteries of cats in a dose-dependent manner. The increased tone of the tissue did not return to the resting level after repeated washings. No vasodilator response was evoked by endothelin in the presence of an active tone. The contractile response of cerebral arteries was not inhibited by rubbing of the endothelium, cold storage denervation or indomethacin. In contrast, nicardipine or diltiazem antagonized the endothelin-induced contraction non-competitively. No contraction was evoked by endothelin in a Ca2+-free solution while the addition of Ca2+ ions in the presence of endothelin in a Ca2+-free solution caused a sustained contraction. Ca2+-induced contraction in the Ca2+-free solution containing endothelin was also inhibited by nicardipine. Therefore, endothelin causes a direct contraction of the smooth muscles of cat cerebral arteries, probably by activating the influx of Ca2+ ions through L-type Ca2+ channels of smooth muscles.  相似文献   
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It is well known that long-term infection with Clonorchis sinensis often causes bile duct cancer, usually. It occurs in the intrahepatic bile duct. We encountered a rare case of clonorchiasis complicated with duodenal papillary cancer. The patient was a woman from China. Although clonorchiasis is rarely found in Japan, the promotion of international exchange may increase the number of visitors from endemic areas. Thus we must pay sufficient attention to this disease. Also, we reported that the microplate ELISA technique was useful in the diagnosis of clonorchiasis with high accuracy in this case.  相似文献   
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BACKGROUND: Deposition of proteins on surfaces of medical devices has been recognized to putatively relate to the process of regulation of biomaterial-associated complications by attachment of fibrin clots, eukaryotic cells, and microbes. The molecules adsorb to a varying extent, depending not only on the physicochemical properties of the biomaterial, but also on the composition of the host fluid. OBJECTIVE: Adsorption of proteins on catheters exposed both ex vivo and in vitro to dialysate of patients on peritoneal dialysis (PD) was studied. METHODS: Peritoneal dialysis effluent was collected from 5 patients with end-stage renal disease on continuous ambulatory PD. Tenckhoff catheters were obtained from 16 patients. Deposition of proteins on excised Tenckhoff catheters and tubing of different materials exposed to PD effluent in vitro was studied using 125iodine-labeled antibodies. Adhesion of Staphylococcus aureus and Staphylococcus epidermidis strains was quantified on tubing exposed to PD effluent in vitro. RESULTS: The presence of albumin, transferrin, immunoglobulin G, fibrinogen, fibronectin, von Willebrand factor, vitronectin, and thrombospondin was determined at various concentrations in PD effluent. All proteins analyzed were detected on PD catheters removed from patients. The extent of protein deposition on Tenckhoff catheters exposed to PD effluent, in vitro, rapidly reached a plateau and remained constant, as it did on polyvinyl chloride and polyethylene tubing. Adhesion of staphylococci was enhanced on Tenckhoff catheters exposed to PD effluent compared to unused PD solution. CONCLUSIONS: The data identify surface exposed proteins that may serve as adhesion sites for microbes on peritoneal catheters indwelled in patients undergoing PD.  相似文献   
10.
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).  相似文献   
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