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991.
992.
Metastatic calcifications according to histopathologic and scintigraphic findings have been well-defined. The authors report a postoperative case of hyperparathyroidism with multiple metastatic calcifications in the lung, kidney, stomach, heart, and vessels that were primarily detected by bone scintigraphy and demonstrated by CT. Tc-99m MDP bone scintigraphy showed a markedly increased accumulation of radioactivity diffusely throughout the lung, left ventricular wall, both kidneys, and the gastric cardia and body. In the lung, plain films showed almost normal lung. CT, however, demonstrated patchy, slightly increased densities in the lung bilaterally. Cardiac CT indicated a considerably increased density of the ventricular myocardium and remarkable calcification in or near the atrioventricular septum or annulus fibrosus. Upper abdominal CT demonstrated increased densities diffusely throughout the gastric mucosa and renal cortex. Only vascular calcifications were depicted by plain films. Using both bone scintigraphy and CT provides accurate information about each lesion and each tissue, allowing precise diagnosis of even a questionable lesion in the early stage of metastatic calcification. Early diagnosis and early therapy offer the best chance for cure or palliative therapy.  相似文献   
993.
The survival rate and elastic properties of the anterior abdominal skin flap in Sprague-Dawley rats were studied in three groups of animals. In group 1 where the flaps were supplied by a normal artery, arterial flaps (1A) had better survival rate and elastic properties than venous flaps (1B). In group 2, where the flaps were supplied by an artery with diminished perfusion pressure, the arterial flaps (2A) still had slightly better results than venous flaps (2B). However, in group 3 where the flaps were supplied by a vein, venous flaps (3B) had better results than arterial flaps (3A).  相似文献   
994.
A 51-year-old man was admitted because of hemoptysis. Physical examinations and chest XP revealed no abnormal findings. Fiberoptic bronchoscopy showed pulsatile bleeding at the orifice of right B6. Right bronchial arteriography showed a markedly dilated and tortous bronchial artery and shunting to the pulmonary arterial system in the middle and lower lobes. Pulmonary arteriography showed complete obstruction of the right middle lobar and lower lobe segmental arteries (A6, 9, 10). The hemoptysis was thought to be due to increased blood flow of the right bronchial artery, which compensated for reduced right pulmonary arterial flow. Right middle and lower lobe resection was done to prevent further hemoptysis. The resected specimen revealed old thromboemboli in the right middle and lower lobe pulmonary arteries. In this case old pulmonary embolism should be considered as a cause of intrabronchial bleeding.  相似文献   
995.
A 67-year-old male diagnosed clinically as having rheumatoid pleuritis and bronchiolitis was treated with adrenocorticosteroid. His clinical findings improved, but following the tapering of the steroid dose, exacerbation occurred. After the steroid dose was increased, serological findings improved, but chest X-ray findings revealed no improvement. To re-evaluate the etiology of the bronchiolar lesion, open lung biopsy was performed. The biopsy specimen showed lymphocytic infiltration and formation of lymphoid follicles in and around the bronchioles. The pulmonary lesion was diagnosed as follicular bronchiolitis.  相似文献   
996.
The accumulation of modified proteins in aging is well documented in many aging models. For example, the deamidated isoforms of triosephosphate isomerase accumulate in: (a) old erythrocytes, (b) fibroblasts from old donors, (c) fibroblasts aged in vitro, (d) premature-aging syndromes and (e) old cells in the eye lens. However, a fundamental remaining question is: 'Do such modified proteins interfere with cellular function?' It has been difficult to assess this question at the molecular level using whole-organism models and equally frustrating to evaluate the physiological significance of such changes using classical cellular models. Tissue equivalent systems (TES) provide an opportunity for examining the molecular basis and physiological consequences of modified proteins during aging. TES are composed of differentiating and proliferating heterogeneous cell types with symbiotic cell-cell and cell-matrix interactions. They closely resemble, both morphologically and functionally, the tissues from which they were derived. Aging studies utilizing TES can provide information on modifications of protein structures, isozyme patterns, enzymes of the cellular environmental protection system and metabolic parameters which may regulate protein synthesis and degradation.  相似文献   
997.
In 53 elderly participants aged more than 60 the thoracic aorta and bilateral carotid arteries were observed with noninvasive techniques, MRI and ultra-sonography, in order to elucidate the relationship between hypercholesterolemia and atherosclerosis in the elderly. Hypercholesterolemic subjects were classified as group H (serum total cholesterol (TC) greater than 220 mg/dl), group H-I (220 mg/dl less than TC less than 250 mg/dl) and group H-II (TC greater than or equal to 250 mg/dl). Atherosclerotic changes of the thoracic aorta were observed in 46% of group H, 27% of group H-I, 60% of group H-II and 37% of normolipidemic subjects (group NL). Carotid atherosclerotic changes were observed in 19% of group H, 9% of group H-I, 27% of group H-II and 18% of group NL. In group H-I, the percentages of atherosclerotic changes in both thoracic aorta and carotid arteries were lower than those in group NL. However, atherosclerotic changes of thoracic aorta and carotid arteries were detected in 43% and 29% of the subjects showing higher apo B/Apo Al ratio than 1.0 among group H-I + NL (TC less than 250 mg/dl). These changes occurred in 32% and 13% of the subjects showing lower apo B/Apo Al ratio than 1.0 among the same groups. Namely, atherosclerotic changes of the thoracic aorta and carotid arteries were observed more frequently in the subjects showing a higher apo B/Apo Al ratio than 1.0 even if their serum cholesterol values were not higher than 250 mg/dl. We should use not only the serum cholesterol value but also the apo B/Apo Al ratio as an indicator to evaluate the roles of lipids in the development of atherosclerosis.  相似文献   
998.
999.
雷公藤生物碱的分离鉴定   总被引:8,自引:0,他引:8  
我们从雷公藤(TripterygiumWilfordiiHook.f.)中按常法分离得到总碱后经HPLC分析出现8个峰,经硅胶柱层析及硅胶RP-18反相中压柱层析分离得到5个生物碱,由化学方法和光谱分析证明为雷公藤吉碱(Wilforgine20).雷公藤次碱(Wilforine21),雷公藤春碱(Wilfortrine22),雷公藤碱戊(Wilforidine23),呋喃南蛇碱(Celafurine16)。HPLC分析指出含量最高为雷公藤吉碱,其次为呋喃南蛇碱。  相似文献   
1000.
Recombinant forms of normal glycophorin C (GPC), carrying the high frequency Gerbich blood group antigens, and its natural deletion mutants of Yus and Ge type (all combined with oligohistidyl tag) were expressed in CHO and COS 7 cells. The stable expression of all recombinant forms of GPC in CHO cells was obtained, but the level of expression was low and detectable only by flow cytometry. The high level of transient expression of GPC recombinant forms in COS 7 cells allowed their purification on Ni-NTA-agarose. The purified recombinant GPC and mutants of Yus and Ge type behaved in SDS-PAGE similarly to normal GPC forms from RBC membranes. The recombinant GPC.Yus and GPC.Ge mutants appeared as diffuse bands, suggesting the similar heterogeneity of glycosylation that was observed in natural GPC.Yus and GPC.Ge glycoproteins. The flow cytometry analysis of the transfected CHO and COS 7 cells showed that binding of anti-GPC monoclonal antibodies to GPC variants was accordant with the known fine specificity of these antibodies. The obtained recombinant forms of GPC carrying common Gerbich antigens may be useful in serology, and also as model molecules for structure-function studies.  相似文献   
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