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51.
Streptococcus sanguis, usually considered a nonpathogen of the oral cavity, was isolated from blood cultures from a patient who was subsequently found to have a cecal adenocarcinoma. Further studies are needed to determine if Streptococcus sanguis infections have diagnostic implications similar to those of Streptococcus bovis. © 1995 Wiley-Liss, Inc. 相似文献
52.
Takakura Yoshinobu Fujita Takuya Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1990,7(4):339-346
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight. 相似文献
53.
对10例经手术证实的肝包虫囊肿(又称细粒棘球蚴病)的磁共振成像(MRI)进行分析,认为其特征性表现为:囊壁呈光滑厚薄均一的低信号的包膜,在T2加权像上显示更加清楚;母囊内有数个大小不等的子囊,整个病灶呈多房性似玫瑰花状。本文对肝包虫囊肿与肝内其它囊性占位病变的鉴别诊断进行了探讨。 相似文献
54.
Goichi Yotsumoto Koki Tanaka Naoki Ishizaki Akira Ikoma Sumihiro Kawashima Akira Taira 《Surgery today》1997,27(7):657-660
We report herein a case of spontaneous subcapsular hepatic hemorrhage which occurred in a 33-year-old woman 1 day after she
had been delivered of her second child by cesarean section following an uneventful pregnancy. She complained of right upper
quadrant pain on the 1st postoperative day, and computed tomography (CT) showed subcapsular low-density masses in both liver
lobes, while extravasation was demonstrated by CO2 intraarterial digital subtraction angiography (IADSA). The hemorrhage was successfully controlled by transcatheter arterial
embolization (TAE). However, on the 3rd day after TAE, an exploratory laparotomy was performed to establish an exact diagnosis
to explain the persistent abdominal pain and abnormal liver function tests. Subcapsular hematomas in both lobes were confirmed
and no visible laceration was present. The patient recovered gradually by spontaneous absorption of the hematomas and was
discharged on the 22nd postoperative day. Spontaneous hepatic hemorrhage associated with pregnancy is a very rare complication,
and establishing a correct diagnosis and initiating appropriate therapy are essential for this life-threatening disease. 相似文献
55.
56.
目的:探讨垂体脓肿的临床特征和治疗。方法:回顾性分析14例垂体脓肿患者的临床表现、影像学特征、诊断和治疗,并结合文献进行分析。结果:14例患者中头痛13例,垂体功能低下6例,视力视野影响6例,多饮多尿3例,发热3例。MRI增强病灶均呈环状强化。11例经蝶手术治疗,3例经开颅手术。术后随访头痛缓解者10例,视力、视野改善者4例,尿崩者2例恢复正常,垂体功能低下者中4例恢复正常,3例开颅手术者中2例复发,再经蝶手术治愈。结论:应用常规CT和MR术前诊断垂体脓肿困难,对鞍区囊性病变应考虑到垂体脓肿的可能。及早手术、正确选择手术入路、围手术期合理应用抗生素和适当的对症治疗是治疗垂体脓肿的关键。 相似文献
57.
肝腺瘤的影像学诊断 总被引:5,自引:1,他引:4
目的探讨影像学(US、CT、MRI及DSA)诊断肝腺瘤的价值。方法回顾性分析经手术、病理证实的11例肝腺瘤的影像学表现,其中11例行US和CT检查(有1例行CT灌注成像,CTP),5例行MRI扫描,4例行DSA检查,并与手术病理所见对照。结果11例肝腺瘤均为单发肿块,无肝硬化背景,直径2.0~10.0cm。影像学表现:US检查,10例呈稍低或不均匀稍强回声,边界清晰,6例见低回声晕,彩色多普勒显示肿块内有较丰富的血流;CT检查,10例为稍低或等密度,8/10例动脉期全瘤明显强化,门脉期轻度强化,延迟期呈等密度,1例平扫和延迟期呈等密度,动脉期中度强化,门脉期轻度强化,误诊为血管瘤。1/11例CT灌注成像(CTP)检查,肝动脉灌注量(HAP)=1.08ml/(min.ml),门静脉灌注量(PVP)=0.19ml/(min.ml),肝动脉灌注指数(HPI)=0.85,各参数值与肝癌均有明显不同;MRI检查,5例肝腺瘤均能显示完整包膜,T1WI上2例稍高于肝脏信号,1例呈等信号,2例为稍低信号,T2WI上5例均表现为以稍高信号为主的混杂信号,脂肪抑制像(STIR)1例呈略低信号,4例信号与T2WI相似,行增强扫描的4例病灶动脉期显著强化,门脉期强化减退,平衡期呈等信号。DSA检查,3/4例病灶见粗细不均的异常血管影,实质期可见肿瘤染色表现。结论肝腺瘤的US和DSA表现均缺乏特异性,CT、MRI则具有一定的特点。CTP对肝腺瘤可能具有诊断和鉴别诊断价值。 相似文献
58.
目的 研究还原型谷胱甘肽对大鼠肝星状细胞(hepatic stellate,cells,HSC)中金属蛋白酶1组织抑制因子(TIMP-2)表达的影响。从分子和蛋白水平探讨还原型谷胱甘肽对大鼠肝纤维化的作用和可能机制。方法 采用50%CCl4制备大鼠肝纤维化模型,在造模过程中给予还原型谷胱甘肽进行干预。应用RT-PCR才Western Blot技术,在分子和蛋白水平检测体外分离大鼠HSC中的TIMP-1的表达情况。结果 还原型谷胱甘肽干预组与模型组和正常对照组相比,HSC中TIMP的表达降低(P<0.05)。结论 还原型谷胱甘肽的干预可下调大鼠HSC中TIMP-1的表达,对实验性肝纤维化起到减轻作用。 相似文献
59.
Karl Lehner M.D. Maximilian Reiser Ulrich Gebhardt Andreas Heuck Jürgen Schaff 《Cardiovascular and interventional radiology》1987,10(2):71-74
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized
by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic
agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining
aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific
details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only. 相似文献
60.
Background : The present paper addressed the issue of whether pretreatment with intravenous (IV) chemotherapy affects response rate or survival in patients receiving hepatic artery chemotherapy (HAC). Methods : Case note reviews of 164 patients treated in a teaching hospital from June 1990 to July 1996 were carried out. Results : The response rate and carcino-embryonic antigen (CEA) fall in the two groups was almost identical. There was a nonsignificant survival advantage in the non-pretreatment group. Conclusions : Previous administration of IV chemotherapy did not affect the CEA response of patients receiving HAC. 相似文献