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排序方式: 共有1008条查询结果,搜索用时 31 毫秒
111.
RG Lee K Nakamura AC Tsamandas K Abu-Elmagd H Furukawa WR Hutson J Reyes JS Tabasco-Minguillan S Todo AJ Demetris 《Gastroenterology》1996,110(6):1820-1834
BACKGROUND & AIMS: Intestinal transplantation is a developing therapeutic option for patients with irreversible intestinal failure or short bowel syndrome. The aim of this study was to delineate the histopathology of human intestinal allografts and to define the features of intestinal rejection. METHODS: The histological features of 3015 endoscopic biopsy specimens and 23 allograft specimens from 62 intestinal recipients were analyzed retrospectively and correlated with clinical findings. RESULTS: Acute allograft rejection was characterized by a varying combination of crypt injury, mucosal infiltration primarily by mononuclear cells (including blastic lymphocytes), and increased crypt cell apoptosis (more than 2 per 10 crypts). It represented a patchy, often ileal-centered process that could progress to mucosal ulceration; later episodes (more than 100 days posttransplant) tended to show lesser cellular infiltration and greater apoptosis than earlier episodes. Correlation with clinical rejection was good (false-positive rate of 9%; false-negative rate of 26%). Two resected specimens showed obliterative arteriopathy indicative of chronic rejection. In other specimens, preservation injury, cytomegalovirus infection, post-transplant lymphoproliferative disorder, and nonspecific features of active or past mucosal injury could be recognized. CONCLUSIONS: Mucosal biopsy specimens are a useful means of monitoring intestinal allografts. Based on features validated by clinical correlation, acute rejection can be identified reliably and can be differentiated from the other pathological processes affecting the intestinal allograft. (Gastroenterology 1996 Jun;110(6):1820-34) 相似文献
112.
The biochemical and clinical consequences of 2'-deoxycoformycin in refractory lymphoproliferative malignancy 总被引:4,自引:1,他引:4
Grever MR; Siaw MF; Jacob WF; Neidhart JA; Miser JS; Coleman MS; Hutton JJ; Balcerzak SP 《Blood》1981,57(3):406-417
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration. 相似文献
113.
Orbital dermoids: features on CT 总被引:3,自引:0,他引:3
The computed tomographic (CT) features of orbital dermoids were retrospectively reviewed in 17 patients; 15 of the lesions were proved histologically. On the basis of clinical and CT features, the tumors were classified as superficial or deep. All but one were extraconal in location. Seven lesions appeared cystic; only six showed typical fat density. The presence of a margin or rim, often partially calcified, was identified in ten lesions. Irregular scalloping of adjacent bone was a highly suggestive feature, occurring with 11 dermoids. Other bone changes, such as linear defects, thinning, or sclerosis, also occurred. Superficial dermoids showed less apparent bone changes. An extraconal orbital lesion associated with adjacent bone thinning or notching should raise the possibility of a dermoid, especially if a rim with calcification is seen. The appearance is pathognomonic if fat density is also present. 相似文献
114.
One hundred six patients underwent extracorporeal shock wave lithotripsy for cholelithiasis. Of these, 28 patients underwent cholangiographically guided lithotripsy for bile duct stones to assist nonoperative stone removal by endoscopic or radiologic intervention. Fragmentation occurred in 20 of 28 cases (71%) with an average of two lithotripsy sessions. Hemobilia was observed in four patients (14%) for a 24-hour period. Seventy-eight of the 106 were outpatients with symptomatic cholecystolithiasis with one to five calculi who underwent cholecystographic or ultrasound-(US) guided shock wave lithotripsy as definitive therapy. US examination showed stone fragmentation in 86% of cases. With an average of 1.6 treatment sessions and 4,750 shocks, fragments were 4 mm or smaller in 46% of patients. Nine percent of patients had no fragments after an average of 10 weeks, but long-term follow-up is not yet available. Two patients developed acute pancreatitis attributable to fragment passage and one patient acute cholecystitis, likely due to cystic duct obstruction by a fragment. 相似文献
115.
Bangert BA; Modic MT; Ross JS; Obuchowski NA; Perl J; Ruggieri PM; Masaryk TJ 《Radiology》1995,195(2):437
116.
117.
应用乙酰胆碱选择性微电极技术,观察到小剂量赛拉嗪(2.0和6.0mg·kg-1)可显著增加大鼠海马CA1区ACh的含量,而大剂量赛拉嗪(10.0mg·kg-1)及咪唑克生(0.6mg·kg-1)则作用相反。咪唑克生虽可明显拮抗赛拉嗪的作用,但海马CA1区ACh的含量仍显著低于正常水平。在去兰斑核的大鼠上,赛拉嗪(2.0和6.0mg·kg-1)及咪唑克生(0.6mg·kg-1)分别对海马CA1区ACh的含量具有减少和增加作用,且咪唑克生拮抗赛拉嗪的作用后,海马CA1区ACh的含量基本恢复至正常水平。结果提示,赛拉嗪对麻醉大鼠海马CA1区ACh含量呈双相性影响,咪唑可生虽能显著拮抗赛拉嗪的作用,但海马CA1区ACh的含量仍明显低于正常水平,可能分别与赛拉嗪和咪唑克生降低或提高中枢NE能系统的功能有关。 相似文献
118.
119.
Temporal lobes: surface MR coil phased-array imaging 总被引:1,自引:0,他引:1
120.