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11.
Primary leiomyosarcoma of the thyroid gland   总被引:1,自引:0,他引:1  
Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically, the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be essential in the treatment of this rare but rather aggressive malignancy.  相似文献   
12.
We compared peroxidizability of neonatal and adult lipoproteins exposed to oxidative stress initiated by an azo-compound. Oxygen uptake showed a two-phase pattern, with slow oxygen uptake in the first phase and faster uptake in the second phase. During the first phase, tocopherol was consumed progressively, inhibiting lipid peroxidation by scavenging peroxy radicals. After the tocopherol concentration fell below a critical level, extensive propagation of chain oxidative reactions produced the rapid oxygen uptake in the second phase. In the first phase of neonatal lipoprotein oxidation, a faster oxygen uptake was observed and the length of this phase was shorter than in adults. The oxygen uptake rate in the second phase was smaller in the neonatal lipoproteins. In other words, neonatal lipoproteins were more susceptible to oxidative stress than were adult ones when tocopherol remained in lipoproteins, but after tocopherol depletion the reverse was true. These results were consistent with the finding that in neonatal lipoproteins the tocopherol/lipid ratio was significantly lower (length of the inhibitory phase was closely correlated to the lipoprotein tocopherol content). In addition, the average number of active bisallylic hydrogen atoms, which are considered to determine the relative susceptibility of polyunsaturated fatty acids to oxidation, was significantly smaller (oxygen uptake rate in the second phase was closely correlated to the active bisallylic hydrogen number) in neonatal lipoproteins, and the ratio of active bisallylic hydrogen to tocopherol content (which closely correlated to oxygen uptake rate in the first phase) was also significantly lower compared with the adult ratio. Under physiologic conditions, an intensive oxidation of lipoproteins sufficient to cause lipoprotein tocopherol to fall below critical levels is unlikely to occur.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
13.
We studied the long-term outcome of 268 patients suffering fromdiabetic end-stage renal disease (DM-ESRD) treated with long-termhaemodialysis between 1978 and 1991, with special emphasis onvisual acuity as well as the heterogeneity of DM-ESRD The 50%patient survival on haemodialysis was 60 months. Visual disturbanceswere found in 73.1% (392/536) of eyes at the start of haemodialysis.Chronological assess ment of visual acuity demonstrated thestabilization of visual acuity and 87.1% (364/418) of eyes werestable, 4.8% (20/418) were improved, and 8.1% (34/418) wereaggravated in the long term respectively. The change of visualacuity was frequently seen in the short term, and rapid shiftsof body fluid to correct overhydration induced abrupt changesof glycaemic control as well as retraction of macular oedema.Hence it might be one of the factors affecting rapid changeof visual acuity in the short term. Meanwhile, long-term deterioration of visual acuity resulted from either hyperten sionunresponsive to medical treatment or poor glycaemic control.Some DM-ESRD patients had only background retinopathy at thestart of haemodialysis and these were likely to have the nephroscleroticglomerular lesion. They were old, not nephrotic and had a milddegree of diabetes during the predialysis stage. Thus, DM-ESRDpatients seem to have some heterogeneity in their clinical characteristics,and old DM-ESRD patients with only background retinopathy havethe appearance of diabetic macroangiopathy rather than microangiopathy.  相似文献   
14.
Transient induction of single GST-P positive hepatocytes by DEN   总被引:12,自引:3,他引:9  
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible ‘initiated cells’,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 2–24 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules.  相似文献   
15.
16.
In order to study the relationship between personality and the development of diabetic retinopathy in patients with diabetes mellitus, diabetics with retinopathy (severe group) and sex-, age-, and duration-matched diabetics without complications were tested by psychological tests, and interviewed. The result of the Yatabe-Guilford personality test (Y-G) and Spielberger's State and Trait Anxiety Inventory revealed that subjects were emotionally and socially stable and well-adjusted types and less anxious in the severe group than in the mild group. The interview findings reveal that the severe group had neglected the medical treatment and the diet therapy for significantly longer periods of time and the incidence of a childhood parental separation was significantly higher in the severe group than in the mild group. Discussion focuses on the severe diabetics' coping behavior which is characterized by the neglect of medical treatment and diet therapy for extended periods of time, which in turn resulted in diabetic retinopathy and other complications. Such coping behavior is shown to be equivalent to that found in the alexithymic behavioral syndrome.  相似文献   
17.
Immunohistological study on malignant fibrous histiocytoma   总被引:2,自引:0,他引:2  
Malignant fibrous histiocytoma (MFH) shows a mixed proliferation of both fibroblastic and histiocytic cells. Because of their complex morphologic appearances, the nature of truly neoplastic cells in MFH has been controversial. In the present study, immunoperoxidase method (PAP method) was used to examine the intracytoplasmic lysozyme (LY), alpha-1-antitrypsin (A1AT), fibronectin (FN), and polyvalent immunoglobulin (PI) in the fibroblastic and histiocytic cells. Twenty-three cases with MFH were histologically divided into three groups; predominantly fibroblastic type (Group I; 5 cases), mixed fibroblastic and histiocytic type (Group II; 15 cases), and almost pure histiocytic type (Group III; 3 cases). Fibroblastic cells showed a strong positive reaction for LY and A1AT, suggesting the histiocytic nature, while the proliferating cells in Group II were more intensely stained by each of the antibodies than in Groups I and III. Enzyme histochemical examinations on fresh materials were available in 3 cases. These findings suggest that proliferating cells in MFH possess a histiocyte nature.  相似文献   
18.
A rare case of serous papillary cystadenocarcinoma of the ovary showing chondrosarcomatous differentiation in a metastatic deposit late in the clinical course is reported. A 49-year-old female underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy for bilateral ovarian tumors. Histological diagnosis was serous papillary cystadenocarcinoma of both ovaries with lymph node metastasis. After six courses of chemotherapy, she was confirmed to be in complete remission following a second laparotomy. Following additional chemotherapy, a third laparotomy disclosed swollen left inguinal lymph nodes. In one of these nodes, approximately 5.0 cm in greatest diameter, the predominant histological features were: chondrosarcoma of the bone and soft tissue, with small foci of serous papillary adenocarcinoma and squamous epithelium. A histological transition between mesenchymal and epithelial areas was identified. Immunohistochemical positivity for broad-spectrum cytokeratin (AE1/AE3), vimentin, epithelial membrane antigen, and S-100 protein was observed in both chondrosarcomatous and epithelial areas. The current evidence may suggest that the chondrosarcomatous differentiation was derived from the metastatic epithelial component.  相似文献   
19.
BACKGROUND: Terminal deoxynucleotidyltransferase (TdT) is a DNA polymerase that enhances the Ig and TcR gene diversity in the N region at the junctions of variable (V), diversity (D) and joining (J) segments in B- and T-cells. TdT synthesizes the N region in concert with many proteins including DNA-PKcs, Ku70 and Ku86. To elucidate the molecular mechanism of the N region synthesis, we first attempted to isolate the genes with products that directly interact with TdT. RESULTS: Using a yeast two-hybrid system, we isolated a cDNA clone encoding a novel nuclear protein that interacts with TdT. This protein was designated as TdT interacting factor 2 (TdIF2). The confined region of the C-terminal in TdIF2 is involved in specific interaction with the entire C-terminal in TdT. TdIF2 contains an acidic region comprised of 42 residues. TdIF2 was shown to bind specifically to a core histone by pull down assay using specific antibodies against TdIF2. When a TdT/TdIF2 complex was applied on to a DNA-cellulose column, only TdT bound to the column while TdIF2 passed through. TdIF2 reduces the TdT activity to 46% of its maximum value in vitro assay system using activated DNA as primer. CONCLUSIONS: TdIF2 binds directly to TdT and core histone. Furthermore, TdT, TdIF2 and core histone form a ternary complex. TdIF2 liberates H2A/H2B from a core histone in correlation with PCNA. The enzymatic consequence of the TdIF2/TdT complex is the reduction of TdT activity in vitro. TdIF2 would function as a chromatin remodeling protein at the N region synthesis.  相似文献   
20.
Gangliosides isolated from the brain of patients with Creutzfelt-Jakob (C-J) disease were analyzed. The ganglioside current was abnormally low, and the percentage distributions of individual gangliosides and the long-chain base compositions were abnormal. The C20-sphingosine contents of all the ganglioside fractions were low. Abnormalities in ganglioside long-chain bases in adult human brain have been reported previously only in patients with inherited metabolic disorders. These abnormalities in C-J disease seem to be closely related to the cause of the disease.  相似文献   
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