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991.
992.
Correlated observations and analysis of maturation-ameloblast morphology and enamel mineralization 总被引:1,自引:0,他引:1
A combined HCl-collagenase digestion technique and scanning electron microscopy were used to isolate the enamel organ and to confirm the presence of maturation ameloblasts of both ruffle-ended (RA) and smooth-ended (SA) types on maturing enamel in kitten permanent tooth germs. EDTA perfusion of animals fixed with aldehyde produced two or three belt-like shallow grooves (from 30 to 100 micron wide) running horizontally through the maturing enamel surface, coinciding closely with the SA distribution pattern. In animals that had been perfusion-fixed with unbuffered osmium tetroxide containing 2.5% potassium pyroantimonate, SEM-EDX analysis detected K in a superficial enamel layer overlaid by the SA layer. Potassium concentration decreased gradually toward the deeper layers. Very little K penetrated the enamel under the RA layer. Energy-dispersive x-ray analysis of Ca and P concentrations in the enamel revealed an even distribution of these elements throughout the superficial layer of maturing enamel. These results suggest that the SA layer forms an access route for K and EDTA and that, in spite of the obvious morphological and functional differences between RA and SA, the maturing enamel surfaces overlaid by these two cell types show similar degrees of mineralization. 相似文献
993.
Serum and urinary beta 2-microglobulin (S-, U-beta 2MG), and creatinine clearance (C-cr) were examined in 41 nephrectomy cases, and changes in glomerular and tubular handling of beta 2MG such as filtered beta 2MG (Fil-beta 2MG), reabsorption of beta 2MG (Reab-beta 2MG) and fractional excretion of beta 2MG (FE-beta 2MG) were studied. Serum creatinine (S-cr) and S-beta 2MG increased significantly after nephrectomy. C-cr decreased immediately after nephrectomy (80%), but recovered up to 87% in 2 to 4 days postoperatively. Fil-beta 2MG decreased immediately after nephrectomy, but increased up to more than the preoperative level in 2 to 4 days postoperatively. On the other hand, Reab-beta 2MG decreased significantly immediately after nephrectomy, and it took 5 to 8 days until recovery. Consequently, urinary excretion of beta 2MG (Ex-beta 2MG) and FE-beta 2MG increased significantly 0 to 4 days postoperatively. These increases in Ex-beta 2MG and FE-beta 2MG were much higher than those seen in diabetic nephropathy, cadmium nephropathy and Cis-diamminedichloroplatinum (II) (CDDP) intoxication, and were not due to drug intoxication such as general anesthesia or antibiotics, but due to glomerulo-tubular unbalance. Clinical data of renal tubular handling of beta 2-microglobulin in cases of interferon therapy or unilateral nephrectomy revealed many interesting aspects of glomerulo-tubular adaptations, and micropuncture study or isolated tubule perfusion study are awaited. 相似文献
994.
S Suita T Tajiri M Higashi S Tanaka Y Kinoshita Y Takahashi K Tatsuta 《Zeitschrift für Kinderchirurgie》2007,17(1):23-28
BACKGROUND/PURPOSE: Mass screening (MS) for neuroblastoma (NB) at 6 months of age in Japan was discontinued in 2004. We have previously reported that the majority of NB detected by MS showed a good prognosis, with only a few cases demonstrating an unfavorable outcome (J Pediatr Surg 2002, Cancer 2001). This study aims to provide insights into infant NB by assessing the details of the clinical courses in patients treated with a standard regimen and the biological features of such cases using highly sensitive methods at one institution in Japan. METHODS: In 76 NB detected through MS treated at Kyushu University Hospital, the clinical features and MYCN amplification, 1p deletion, 17q gain, the expression level of TRKA using FISH and the quantitative PCR were analyzed. RESULTS: Of these 76 persons with NB treated at one institution, 97 % are still alive, while 2 cases died from other diseases. Three patients experienced a recurrence after complete remission (CR), and 2 patients demonstrated refractory disease since the initial diagnosis. Two of the 3 NB patients with recurrence have demonstrated a 2nd CR, while one case still has multiple active diseases. Regarding the findings of highly sensitive biological analyses, 5/74 (7 %) showed MYCN amplification, 2/24 (8 %) cases had a 1p deletion, 3/33 (9 %) cases had a 17q gain, 5/50 (10 %) cases had diploidy, 1/25 (4 %) cases had a low expression of TRKA, and 2/76 (3 %) cases had an unfavorable histology. Of the 76 NB, 13 tumors (17 %) had one or more unfavorable factors (UF). Of the 5 refractory NB, 1 case had 3 UF, 1 case had 2 UF, 1 case had 1 UF, and 2 cases had no UF. As a result, 60 % of the refractory NB had one or more UF. CONCLUSIONS: Of the NB detected by MS at one institution in Japan, 17 % had one or more unfavorable factors (UF) and might have a higher risk of recurrence than the patients with no UF, although the unfavorable biology of several refractory cases is still unclear even after highly sensitive analyses. At least one-fifth of the NB cases detected by MS are anticipated cases. In infantile neuroblastomas, it may therefore be most important to analyze biologically prognostic factors using highly sensitive methods followed by immediate surgical intervention. Since the MS program has been discontinued in Japan, it will be necessary in future to assess the mortality and characteristics of NB detected clinically. 相似文献
995.
S Inoue T Nakamura K Hasegawa S Tadaoka M Samukawa S Nezuo T Sawayama Y Higashi T Shirabe 《Journal of cardiology》1989,19(1):323-332
A rare case of pulmonary hypertension due to glycogen storage disease type II (Pompe's disease) was reported. An 18-year-old girl was admitted to Kawasaki Medical School Hospital because of cyanosis, dyspnea on exertion and amenorrhea. She was 149 cm in height and 29 kg in body weight. Clinical examination revealed that pulmonary artery pulse and right ventricular heave were palpable over the precordium. On auscultation, an accentuated pulmonic second heart sound, pulmonic ejection sound and diastolic decrescendo murmur (Levine III/VI) were heard in the second intercostal space at the right sternal border. Her skeletal muscles, especially her intercostal muscles were generally weak and atrophic. Her electrocardiogram showed a pulmonary P-wave and right ventricular hypertrophy. The chest X-ray revealed right ventricular enlargement and a dilated pulmonary trunk. On echocardiography, the right ventricle and the main pulmonary artery were dilated, and a systolic notch of the pulmonary valve was found. Swan-Ganz catheterization disclosed that pulmonary artery pressure, right ventricular pressure and mean pulmonary capillary wedge pressure were 76/35 (50) mmHg, 76/12 mmHg and 10 mmHg, respectively. Respiratory function tests showed severe restrictive ventilatory impairment with hypercapnea and hypoxemia. On biopsy of the left quadriceps femoris muscle, the most striking finding was numerous intracytoplasmic vacuoles. The small vacuoles were stained with PAS and acid phosphatase. Electron microscopy showed massive glycogen accumulation in the sarcoplasm and membrane bound vacuoles (glycogenosome). Alpha-1, 4-glucosidase activity in the peripheral lymphocytes was definitely decreased. Her pulmonary hypertension resulted from respiratory muscular atrophy and alveolar hypoventilation caused by Pompe's disease. 相似文献
996.
A great number of anticonvulsants are available for treating these different types of epilepsy. Therapeutic drug monitoring has been favored as the method for controlling drug concentrations in the plasma and preventing untoward effects. When these anticonvulsants are prescribed to treat epilepsy in children, careful monitoring is most important because drug metabolism varies depending on maturation and development of body functions. Molecular approaches are also important to elucidate the effectiveness of the drugs for treatment of different seizure disorders and should contribute to a better understanding of body functions. 相似文献
997.
Goji Michiyo Suzuki Shigehiko Kawazoe Takeshi Saso Yasumi Mihara Hisayuki Tabata Yasuhiko 《Wound repair and regeneration》2004,12(1):A8-A8
Aim: It is well recognized that bFGF accelerates proliferation of almost all cells concerned with wound healing and there is a report that bFGF was well sorbed with time to the acidic gelatin hydrogel with isoelectric points of 5.0. We investigated the effect of the acidic gelatin sheet containg bFGF. Methods: Full thickness defects of skin (1.5 × 1.5 cm) were created on the backs of mice.1) The wounds were covered with gelatin sheets (2 × 2 cm)containg bFGF(100 ìg/site), (A), and without bFGF(B). The concentration of bFGF in plasma was estimated by ELISA. 2) The wounds were covered with A, B and hydrogel dressing(control group, C) and wound area was measured with computer planimeter and neoepithelium was observed using the light microscope. Results: 1) The concentration of bFGF in plasma in (A) was statistically greater than (B) by the 7th day. 2) Statistically smaller wound area was found 2 weeks postoperatively in (A) than in (C) and (D). Neoepithelium from edge of the wound was statistically longer in (A) than in (C). Conclusions: Controlled release of bFGF from the acidic gelatin sheet was fouhd and acidic gelatin sheet containg bFGF promoted neoepithelization and wound closure. The acidic gelatin sheet containg bFGF was thought to be effective on wound healing. 相似文献
998.
Background
In neuropathological processes associated with neutrophilic infiltrates, such as experimental allergic encephalitis and traumatic injury of the brain, the CXC chemokine, macrophage inflammatory protein-2 (MIP-2) is thought to play a pivotal role in the induction and perpetuation of inflammation in the central nervous system (CNS). The origin of MIP-2 in inflammatory disorders of the brain has not been fully defined but astrocytes appear to be a dominant source of this chemokine. 相似文献999.
1000.
Sakai K Mizumatsu S Terasaka K Sugatani H Higashi T 《Neurologia medico-chirurgica》2005,45(11):574-577
A previously healthy 61-year-old man presented with basal ganglia hemorrhage caused by rupture of a small aneurysm arising from the distal lenticulostriate artery associated with moyamoya-like disease and manifesting as left hemiparesis and dysarthria. The patient underwent frontotemporal craniotomy. Neck clipping of the aneurysm was performed through the hematoma cavity. He was transferred for rehabilitation with left hemiparesis. Three-dimensional computed tomography angiography was very useful for preoperative planning and evaluation of the anatomical correlation between the aneurysm and the hemorrhage. 相似文献