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71.
M Numano Y Tominaga K Uchida A Orihara Y Tanaka H Takagi 《Canadian Metallurgical Quarterly》1998,22(10):1098-102; discussion 1103
In secondary hyperparathyroidism (2HPT) fundamentally all parathyroid glands, including supernumerary glands, become hyperplastic, and stimulation of parathyroid glands continues after parathyroidectomy (PTx). Therefore supernumerary glands have special significance during surgery for 2HPT, whether persistent or recurrent HPT. In the present study 570 patients underwent initial total PTx with a forearm autograft. The frequency, type, location, histopathology, and clinical significance of the supernumerary glands were evaluated. At the initial operation 90 supernumerary glands were removed from 82 to 570 patients (14.4%); 12 patients (2.1%) required extirpation of supernumerary glands for persistent/recurrent HPT. Altogether 104 supernumerary glands were identified at operation in 94 of the 570 patients (16.5%). Among these 104 glands, 25 (24.0%) were of the rudimentary, or split, type and 79 (76.0%) of the proper type. Supernumerary glands were most frequently identified in the thymic tongue (53/104, 51.0%); 32 (60.4%) of these 53 glands were identified only microscopically. In 6 of the 570 cases (1.1%), reoperation was required for persistent HPT due to supernumerary glands located in the mediastinum, and 6 patients underwent neck reexploration for recurrence. Histopathologically, 61 of 104 (58.7%) supernumerary glands, including 36 glands recognized only microscopically, showed diffuse hyperplasia, and 43 (41.3%) displayed nodular hyperplasia. Residual small supernumerary glands with diffuse hyperplasia have the potential to be transformed to nodular hyperplasia during long-term hemodialysis. Therefore all parathyroid glands including supernumerary glands should, if possible, be removed at the initial operation. Routine removal of the thymic tongue and careful examination of the regions surrounding the lower poles of the thyroid, especially on the left side, are important steps in the surgical treatment. 相似文献
72.
T Takubo N Tatsumi I Tsuda K Kasuya Y Taniguchi T Fujita K Uchida Y Matsuo T Hayashi 《Canadian Metallurgical Quarterly》1998,99(4):234-235
Cytomegalovirus (CMV) gastritis has been reported in transplant patients. Symptoms are considered nonspecific, and gastroscopy with biopsy is usually performed to establish the diagnosis. Three patients are described here 1 to 3 months after solid organ transplantation, with primary CMV gastritis, confirmed by gastroscopy, histopathologic examination and cultures. The clinical presentation in all three cases was sharp epigastric pain that decreased in a supine position, increased while sitting and further increased when standing or walking. The epigastric pain completely resolved after treatment with ganciclovir. To the best of our knowledge, such postural epigastric pain has not been described as a specific symptom in any other clinical entity and may be a unique sign of primary CMV gastritis. 相似文献
73.
K Hashimoto M Yamanaka H Uchida Y Saito Y Kosaka 《Canadian Metallurgical Quarterly》1997,46(7):951-954
A perioperative anesthetic management of a 69 year old woman with acromegaly whose clinical course was characterized by severe heart failure is described. The patient showed symptoms of massive cardiomegaly. Endocrine studies indicated that her pituitary tumor was active with hyperproduction of growth hormone. There was no demonstrable evidence for other known causes of heart disease. Following hormonal therapy using continuous subcutaneous infusion of somatostatin for about two months, there was improvement in daily activity and reduction in heart size. After the improvement of cardiac function, transsphenoidal hypophysectomy was performed under general anesthesia and its perioperative course was quite uneventful. We conclude that because cardiac involvement such as left ventricular dilatation in acromegaly might be reversible with proper treatment, any surgical procedure, as long as the case is elective, should be considered after hormone therapy. 相似文献
74.
Distribution and biliary and fecal excretion of bile acids were examined in Wistar strain male rats of about 300 g body weight.
The pool size of the rats on ordinary diet was 40 mg/rat, biliary secretion was 14 mg/hr, and fecal excretion was 10 mg/day.
Bile acids were mainly located in the small and large intestinal contents, 87% and 10%, respectively; but a portion was found
in the intestinal wall and the liver. Rats fed 2% cholesterol-supplemented diet for a week showed similar values for pool
size and biliary secretion with the rats on ordinary diet, but higher values for fecal excretion and distribution ratio in
the large intestinal contents. Cholic acid was a major component in the bile, small intestinal wall, small intestinal content
and liver, while the bile acid composition ratios were roughly similar to each other, although a relatively large amount of
α-muricholic acid was found in the intentinal wall and liver. Both the wall and content compositions of the large intestine
were similar to that of the feces, in which lithocholic, deoxycholic, α- and β-muricholic acids were the main components,
although the ratios of α- and β-muricholic acids in the large intestinal wall were larger than those in the intestinal contents
or feces. The high concentrations of these bile acids may indicate a difference of transport velocity across the cell membrane,
but the mechanism is not known. 相似文献
75.
The action of ricin toxin was stimulated by addition of methylamine or some other amines, as shown by measuring the inhibition of protein synthesis of cultured cells by the toxin. Under the same conditions, however, the action of diphtheria toxin was completely inhibited by the amines. In a cell-free protein-synthesizing system, methylamine had no effect on the action of the A chain of ricin toxin and fragment A of diphtheria toxin. Studies on the interactions of 125I-labeled toxins with cells revealed that methylamine did not alter toxin-receptor bindings, but affected the entry of the toxins into the cells. Studies were also made on the effects of methylamine on the actions of two hybrid toxins, formed from a subunit of Wistaria floribunda lectin and fragment A of diphtheria toxin and the A chain of ricin toxin, respectively. Results suggested that the processes of entry of ricin toxin and diphtheria toxin, or at least parts of these processes, are different. 相似文献
76.
Recently, the problem of absorption of gases into nonhomogeneous solvents has drawn more attention than ever as it found in various fields such as flue gas scrubbing, hydroprocessing, coal conversion and medicine. Since the first treatment of this problem by Ramachandran and Sharma(1), several models based on the film concept have been proposed(2-7). There is, however, no penetration theory for the evaluation of the rate of the absorption of a gas into a slurry containing suspended solid particles. In this paper, a penetration model is presented for the absorption of gas A into a slurry containing solid B with an instantaneous irreversible chemical reaction. 相似文献
77.
Yoshinori Suzuki Takashi Uchida Masataka Wakihara Masao Taniguchi 《Materials Research Bulletin》1981,16(9):1085-1090
Changing the partial pressure of sulfur Ps2 at temperatures of 750° and 950°C, phase equilibria on the Mo-S system by solid-gas reaction were investigated. Hexagonal 2H-MoS2 and monoclinic Mo2S3 phases were identified from the x-ray powder diffraction pattern. The 2H-MoS2 had a slight homogeneity range, i.e. MoS1.978 to MoS2.0 at 950°C, MoS1.983 to MoS2.0 at 750°C. No remarkable variation of lattice parameters for the MoS2 was observed. The composition of the Mo2S3 phase was not stoichiometric MoS1.5 but MoS1.457 at 950°C. At 750°C the composition of the Mo2S3 phase could not be determined since it was quite difficult to establish the equilibrium state between the gas and the condensed phases. This finding agreed well with the result of Morimoto and Kullerud. 相似文献
78.
79.
Kawata M Uchida H Itatani K Okada I Koda S Aizawa M 《Journal of materials science. Materials in medicine》2004,15(7):817-823
Porous hydroxyapatite (HAp) ceramics possessing well-controlled porosities and pore sizes were developed by firing apatite-fiber compacts mixed with carbon beads and agar. The total porosities could be controlled in the range from 40 to 85% by varying compaction pressure (20-40 MPa), firing temperature (1000-1300 degrees C) and carbon/HAp ratio (0/10-10/10 (w/w)). Most of the pores were regarded as open pores. The pore sizes were mainly affected by the carbon-bead diameter (5, 20 or 150 microm) and partly by the compaction pressure and the firing temperature. The pore sizes of the porous HAp ceramics derived from the carbon beads of 150 microm in diameter were distributed in the two separate ranges of several micrometers and more than 100 microm. 相似文献
80.
Yamaguchi A Uejo F Yoda T Uchida T Tanamura Y Yamashita T Teramae N 《Nature materials》2004,3(5):337-341
A mesoporous membrane composed of nanochannels with a uniform diameter has a potential use for precise size-exclusive separation of molecules. Here, we report a novel method to form a hybrid membrane composed of silica-surfactant nanocomposite and a porous alumina membrane, by which size-selective transport of molecules across the membrane becomes possible. The nanocomposite formed inside each columnar alumina pore was an assembly of surfactant-templated silica-nanochannels with a channel diameter of 3.4 nm; the channel direction being predominantly oriented along the wall of the columnar alumina pore. Molecules could be transported across the membrane including the silica-surfactant nanocomposite with a capability of nanometre-order size-exclusive separation. Our proposed membrane system has a potential use not only for separation science, but also catalysis and chip technologies. 相似文献