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1.
目的:比较正常肝组织与肝癌AH 109A,吉田肉瘤中谷氨酸脱氢酶,胆碱氧化酶和葡萄糖-6-磷酸酶的活力对~(67)Ga摄取与积累的影响;方法:制备~(67)Ga枸橼酸溶液给大鼠静注后处死大鼠,制备亚细胞悬液,液闪计数器测定放射活度.结果:~(67)Ga的放射活性在正常肝组织溶酶体中(55%积聚)显著高于肝癌AH109A(32%积聚)和吉田肉瘤(18%)积聚.谷氨酸脱氢酶的活力在正常肝组织,肝癌和吉田肉瘤分别是1830±s 320 U·L~(-1),23±s 6 U·L~(-1)和7±s 2 U·L~(-1);胆碱氧化酶的活力分别是46±s 10 U·L~(-1),25.0±s 0.4 U·L~(-1),2.0±0.4 U·L~(-1);葡萄糖-6-磷酸酶活力分别是2550±s 180 U·L~(-1),84±s 14 U·L~(-1),78±s13 U·L~(-1).结论:正常肝组织中溶酶体酶活力很强,对~(67)Ga的积累起较大作用.癌变组织酶活力降低而作用减弱.吉田肉瘤细胞无肝细胞特点,其溶酶体对~(67)Ga积累作用不大.  相似文献   
2.
BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
3.
Microdialysis has been used to determine the concentration of salicylic acid in skin tissue and plasma periodically for 4 h to evaluate the effect of ointment bases on topical and transdermal delivery of salicylic acid. The ointment bases examined were solbase (water-soluble), poloid and white petrolatum (oleaginous), hydrophilic poloid (water in oil (w/o) type emulsion lacking water) and absorptive ointment (w/o-type emulsion containing water). The ointments (0.1 g) containing 25 μmol salicylic acid were applied for 2 h to the surface of rat skin (1 cm2) with (intact) or without the stratum corneum. For intact skin, the extent of topical delivery from different ointments, evaluated by the area under the concentration-time curve (AUC) of salicylic acid in the skin tissue (AUCskin), increased in the order solbase. white petrolatum, poloid, hydrophilic poloid. absorptive ointment. The ratio of AUCskin (topical delivery) to the AUC of salicylic acid in plasma (AUCplasma, transdermal delivery) varied remarkably among the different bases, the greatest ratio being observed for absorptive ointment. When the ointments were applied to skin surface without stratum corneum, AUCskin for solbase was much higher (about 45 times that for intact skin), whereas only a small (two-fold) increase was observed for poloid and hydrophilic poloid and the increase was negligible for white petrolatum and absorptive ointment. For skin without the stratum corneum, the ratio AUCskin/AUCplasma for the different ointments was comparable, although the magnitudes of AUCskin and AUCplasma still varied substantially. The variance of AUC values arises as a result of the different rates of release of salicylic acid from the bases. These results indicate that: the topical and transdermal delivery of salicylic acid in intact skin varies substantially among different ointment bases, and the greatest topical delivery is observed for absorptive ointment; use of absorptive ointment increases the retention of salicylic acid in the stratum corneum; and the stratum corneum functions strongly as a penetration barrier for solbase, moderately for poloid and hydrophilic poloid, and less for absorptive ointment and white petrolatum.  相似文献   
4.
We describe an experience of a specific immune transfer treatment in a patient with chronic active EBV infection. The patient had low anti-EBV T cell-mediated cytotoxic activity in his peripheral blood mononuclear cells (PBMC), which may have been the primary cause of the disease. An EBV-specific cytotoxic T lymphocyte (CTL) line was established from PBMC obtained from the patient’s sister whose human leucocyte antigens (HLA) are identical to patient's. The patient received three courses of intravenously administered CTL at 3-week intervals. The number of the cells was increased with each course of treatment. After infusion of the T cell line, anti-EBV CTL activity was detected in the patient's PBMC. CTL activity increased markedly after the second course of immune transfer therapy. The amount of EBV DNA in the patient's plasma showed transient but repeated decreases. Serum levels of tumour necrosis factor-alpha (TNF-α), which had elevated before treatment, began to decrease after initiation of treatment. No adverse effects were directly associated with CTL infusions. Despite having previously received a pneumococcal vaccine and prophylactic antibodies, the patient died of infection caused by Streptococcus pneumoniae bacteraemia 27 days after the third infusion. Although the long-term efficacy and safety of this therapy remains to be established, our findings suggest that adoptive transfer of CTL specific for EBV obtained from an HLA-matched donor might be a promising treatment for patients with chronic active EBV infection.  相似文献   
5.
Various types of fibromatosis have been reported in infancy and early childhood. We describe an infant with diffuse fibromatosis on the scalp. A one year and five months-old girl showed a diffuse and hard mass 3 × 5 cm in diameter and no tenderness on the scalp. Two months later, the size of the mass had increased and several other tumors appeared on the lateral head. The magnetic resonance imaging (MRI) disclosed that a large and diffuse tumor had spread from the frontal to occipital head; a ‘helmet-like’ configuration of the tumor was exhibited on sagittal MR images. The tumor showed high signal intensity on T2-weighted images and was enhanced with Gd-DTPA. Histological examination showed a fibroblastic proliferation with intervening thick collagen bundles. The patient was diagnosed as having diffuse fibromatosis. The tumor at the resection site immediately recurred, whereas the tumor in the frontal head showed marked regression. Three months after the resection, new tumors appeared in the occipital head. The size and number of these tumors have remained unchanged for more than 18 months. The sites and appearance of the tumors were identical to that of juvenile hyaline fibromatosis (JHF) in this patient. However, JHF usually includes fibroblasts associated with large amounts of hyalinized collagen-like material, which were not present in our patient. The different histology of JHF comparing our case and other reported cases may depend on the different phase of the disease progression at resection. Long-term observation is necessary for the appropriate diagnosis and evaluation of prognosis in this patient.  相似文献   
6.
Two distinct hereditary defects, vitamin D-dependent rickets type I (VDDR I) and type II (VDDR II), have been recognized in vitamin D metabolism. VDDR I is suggested to be a deficiency of the renal 25-hydroxyvitamin D (25(OH)D)-1α-hydroxylase. Muscle weakness and rickets are the prominent clinical findings. A normal physiologic dose of 1α-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 is sufficient to maintain remission of rickets in this disorder. VDDR II consists of a spectrum of intracellular vitamin D receptor (VDR) defects and is characterized by the early onset of severe rickets and associated alopecia. This can be attributed to mutations in the VDR gene. Massive doses of vitamin D analogs and calcium supplementation is usually required for the treatment; however, the response to therapy is sometimes variable.  相似文献   
7.
目的:合成天然产物taxinine NN-3和taxinine NN-14,研究其对肿瘤细胞的多药耐药逆转活性.方法:以紫杉宁为出发原料,通过选择性水解9,10位的乙酰氧基,制成原乙酸酯后再水解.结果:以紫杉宁为原料经过3步反应,可以同时获得taxinine NN-3,taxinine NN-4两种天然产物,其中taxinine NN-3的收率为25%,taxinineNN-4的收率为68%.结论:高收率地合成了taxinine NN-3和taxinine NN-14.  相似文献   
8.
Cholestatic hepatocellular carcinoma, which grows into the bile duct and causes obstructive jaundice, is rare and difficult to diagnose. A case is presented in which cholestatic hepatocellular carcinoma was detected by deposit of Lipiodol. This is also the first case that was successfully treated by endoscopic retrograde biliary drainage and transcatheter arterial embolization.  相似文献   
9.
10.
Altered intrahepatic pathway of para-umbilical vein in portal hypertension   总被引:2,自引:0,他引:2  
The object of this study was to determine the frequency and characteristics of altered paraumbilical vein in the hepatic parenchyma, developed from portal hypertension, using computed tomography (CT). Two hundred and ninety-two patients who presented with portal hypertension from 1986 to 1996 were studied retrospectively. The pathway of the dilated para-umbilical vein was demonstrated by contrast-enhanced CT. Thirty-one (11%) patients had a dilated para-umbilical vein arising from the left portal vein into the falciform ligament. In 24 (77%) of these patients, the para-umbilical vein followed the expected route, passing through the fissure of ligamentum teres hepatis. The remaining seven patients (23%) displayed the unusual pathway, with the vein arising from the left branch of the portal vein and passing into the hepatic parenchyma. In these seven patients, four had one collateral vein, and three patients had two collateral veins in the liver parenchyma. The dilated para-umbilical vein frequently passes through the hepatic parenchyma in patients with portal hypertension.  相似文献   
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