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41.
Ijiri R Tanaka Y Kato K Misugi K Ohama Y Shinkai M Nishi T Aida N Kondo F 《Pathology international》2001,51(1):16-19
With the application of liver transplantation for patients with biliary atresia (BA), we have had the opportunity to review the clinicopathologic features of the native livers from 10 transplanted BA patients. A single large nodule at porta hepatis (hilar nodule) was noted in three of 10 patients, and an ill-defined nodule-like lesion at porta hepatis was present in two other patients. The three BA patients with hilar nodules were long-term survivors, compared to the patients with nodule-like and those without nodules. The hilar nodules measured between 5.0 cm and 8.0 cm and histologically, they were partly surrounded by fibrous septa with relatively well-preserved liver architectures and fewer inflammatory cells at the portal triads when compared to the surrounding cirrhotic lesions. No nuclear or cellular atypia was observed. Proliferating cell nuclear antigen labeling index was higher in the surrounding cirrhotic lesions than the hilar nodules. The nodule-like lesions at porta hepatis also showed similar light microscopic and immunohistochemical features as the hilar nodules. These hilar nodules did not seem to contain any malignant potential. The benign histology with relatively well-preserved liver architecture and the preferential site of occurrence at porta hepatis where bile seemed to flow more smoothly, suggested possible residues of less-affected hepatic tissues. 相似文献
42.
Intracellular recordings were made from neurones in the locus coeruleus contained within a slice cut from rat pons and maintained in vitro. Most neurones fired action potentials spontaneously at frequencies of between 1 and 5 Hz; this did not arise from spontaneous synaptic input but appeared to result from endogenous properties of the membrane conductances. Under voltage clamp at potentials near threshold for action potential generation (? 55 mV) there was a persistent inward calcium current. This current became less with membrane hyperpolarization and was abolished at about ?70 mV. Two potassium currents were observed. The first had properties similar to that generally described as the “fast” potassium current (IK,A); it flowed transiently (for about 200 ms) when the membrane potential passed from about ?65 to ?45 mV, and was blocked by 4-aminopyridine. The second was a calcium-activated potassium current (IK,Ca); it flowed for several seconds following a burst of calcium action potentials. Spontaneous and evoked action potentials had both tetrodotoxin-sensitive and tetrodotoxin-resistant components. The latter was apparently due to calcium entry. The potential changes occurring during the spontaneous firing of locus coeruleus neurones could be reconstructed qualitatively from the ionic conductances observed. The membrane properties of the locus coeruleus neurones were remarkably uniform; however, about 5% of cells impaled within the region of the locus coeruleus were electrophysiologically distinct. These atypical cells had short duration action potentials, did not fire spontaneously and had large spontaneous depolarizing synaptic potentials. 相似文献
43.
The morphologic feature of mucus leakage appearing in low papillary carcinoma of the breast. 总被引:1,自引:0,他引:1
K Komaki G Sakamoto H Sugano F Kasumi S Watanabe M Nishi T Morimoto Y Monden 《Human pathology》1991,22(3):231-236
This report summarizes the clinicopathologic findings in 11 cases of low papillary carcinoma of the breast accompanied by the morphologic feature of mucus leakage into the mammary stroma. These cases were characterized by two morphologic findings. First, abundant mucus produced by the tumor cells filled the intraductal spaces where neoplastic epithelium formed very low papillary projections, ie, a feature of mucinous-producing low papillary carcinoma in situ. Second, there was expansive leakage of mucus into the mammary stroma occasionally accompanied by a few epithelial cells. All the cases showed a high level of mucus production and contained no elements of invasive ductal carcinoma or ordinary invasive mucinous carcinoma. These cases have no evidence of direct invasion of the mammary stroma by malignant cells. The average age of the 11 patients was 41 years. Foci of microcalcification were seen in some tumors (seven cases; 64%). There were no cases with lymph node metastases. All the patients underwent mastectomy with no adjuvant therapy, and they are currently alive and well. 相似文献
44.
A new method for histamine release from purified peripheral blood basophils using monoclonal antibody-coated magnetic beads 总被引:13,自引:0,他引:13
Nishi H Nishimura S Higashiura M Ikeya N Ohta H Tsuji T Nishimura M Ohnishi S Higashi H 《Journal of immunological methods》2000,240(1-2):39-46
A new method for evaluating histamine release from purified basophils was developed. Basophil-containing leukocytes were directly purified from a small amount of peripheral blood using monoclonal antibody BA312-coated magnetic beads. The purified basophils still rosetted to magnetic beads maintained a normal response to anti-IgE and to dust mite allergen in comparison with the conventional method using washed leukocytes. This methodology facilitates the purification of basophils, anti-IgE- and allergen-induced histamine release, and subsequent histamine determination within only 3 h. The released histamine was analyzed by an enzyme-linked immunosorbent assay (ELISA) with a characteristic detection profile. Since all steps were performed in 96-well microplates, many clinical samples could be analyzed at the same time, permitting easy applications in routine laboratories. 相似文献
45.
Comparison of automated and manual methods for urinalysis 总被引:1,自引:0,他引:1
R J Elin J M Hosseini J Kestner M Rawe M Ruddel H H Nishi 《American journal of clinical pathology》1986,86(6):731-737
The authors compared results for accuracy and precision obtained by a semiautomated prototype International Remote Imaging Systems, Inc. (IRIS) urinalysis workstation (IUW) with those from quantitative manual urinalysis (QMU). Three technologists skilled in urinalysis each performed 172 urinalyses with both the IUW and QMU methods. The results show that the IUW method is likely to yield comparable counts for particulate analytes compared with the QMU, except for casts. The QMU reported significantly (P less than 0.001) more casts than the IUW method. This difference is related to at least a ninefold greater volume of untreated urine examined by the QMU method than the IUW method. The IUW method may provide a more accurate result than the QMU method at very low and high concentrations of particulate analytes. The result from 24 blind duplicate urines also analyzed by each of the three technologists with both methods showed comparable precision for particulate analytes between the two methods except for red blood cells; the QMU method had significantly (P less than 0.001) better precision for this analyte. 相似文献
46.
1. The blocking action of adrenaline on the superior cervical ganglion of the rabbit was investigated with intracellular recording techniques.2. Adrenaline (10(-5)M) blocked initiation of post-synaptic action potentials and decreased the amplitude of excitatory post-synaptic potentials (e.p.s.p.s), but did not hyperpolarize the post-synaptic membrane.3. The depressant action of adrenaline was antagonized by phenoxy-benzamine and dihydroergotamine.4. Acetylcholine depolarizations from iontophoretic ACh were not affected by adrenaline.5. Adrenaline decreased the frequency of miniature excitatory post-synaptic potentials (m.e.p.s.p.s) and decreased the quantal content of e.p.s.p.s in a low [Ca(2+)]: [Mg(2+)] media.6. It was concluded that adrenaline blocks ganglionic transmission by acting at an alpha-adrenoceptive site in the presynaptic nerve terminals. 相似文献
47.
48.
Kouji Katsura Yoshihiko Soga Sadatomo Zenda Hiromi Nishi Marie Soga Masatoshi Usubuchi Sachiyo Mitsunaga Ken Tomizuka Tetsuhito Konishi Wakako Yatsuoka Takao Ueno Tadanobu Aragaki Takafumi Hayashi 《Journal of radiation research》2021,62(2):374
The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals. 相似文献
49.
Kuroda T Go G Ojima S Nishi S Mizuno K 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1993,2(4):221-224
Isolated avulsion fractures of the lesser tuberosity are extremely rare. A 24-year-old woman fell on her back as her arm was forcibly extended and adducted. Radiographs revealed a small fragment of bone beneath the glenoid. Axillary radiography showed the bone fragment and a bone defect of the lesser tuberosity. Computed tomography scan clearly demonstrated those findings. Surgery was performed 3 weeks after the occurrence of the injury. The bone fragment was reduced and fixed by means of two screws. After 3 weeks, light exercise was started. At follow-up 7 months later she had no complaints. Most reported cases involved sudden contraction of the subscapularis tendon. This type of fracture is sometimes misdiagnosed; computed tomography scan is useful for diagnosis. Previously reported cases have similarly demonstrated a good outcome after surgery, except in cases involving children. 相似文献
50.