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21.
We present a case in which multiple pancreatic tumours were diagnosed as metastatic clear cell renal carcinomas with chemical shift MRI (CSI) before surgery. Radiologists may be unable to recognize the loss of intensity on CSI macroscopically. We believe that it is useful to make subtraction images and calculate signal intensity on CSI, even if the lesions are multiple metastatic tumours.  相似文献   
22.
We examined the activity of spermidine/spermine N 1-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.  相似文献   
23.
The lectin-binding properties of 44 cases of serous and mucinous ovarian cystadenoma, tumor of low malignant potential (LMP), and invasive carcinoma were examined histochemically. Wheat germ agglutinin (WGA), concanavalin A (con A), Ulex europaeus agglutinin I (UEA-I), peanut agglutinin (PNA), Ricinus communis agglutinin I (RCA-I), soybean agglutinin (SBA), and Robina pseudoaccacia (RPA) were employed. All the lectins examined were bound to neoplastic epithelial cells of benign and malignant tumors, but none bound exclusively to ovarian tumor cells. Different lectin-binding patterns between serous and mucinous neoplasms were observed, with the exception of RPA. UEA-I, con A, RPA, and PNA in serous neoplasms and UEA-I, RPA, and WGA in mucinous neoplasms demonstrated lectin-binding properties of LMP tumors intermediate between those of cystadenoma and invasive carcinoma. These findings indicate that serous and mucinous ovarian neoplasms contain different glycoconjugates, that malignant transformation of the neoplasms is associated with alteration of these glycoconjugates, and especially that LMP tumors have a different composition of cellular glycoconjugates from that of invasive ovarian carcinoma.  相似文献   
24.
Endosonography‐guided celiac plexus neurolysis (EUS‐CPN) safely and effectively relieves pain associated with intra‐abdominal malignancies when the neurolytic is accurately injected. We applied contrast medium to evaluate the ethanol injection sites in patients who received EUS‐CPN due to abdominal pain caused by malignancies. We injected, under the guidance of endoscopic ultrasonography (EUS), ethanol containing 10% contrast medium into the celiac plexus of patients with intra‐abdominal pain due to malignancies. Immediately after the endoscopic therapy, patients underwent computed tomography (CT) to confirm the injection site. Images of distribution of injected solutions were classified into three groups. Injected solution dispersed in unilateral and bilateral anterocrural space was defined as ‘unilateral injection’ or ‘bilateral injection’, respectively. Injected solution located out of the anterocrural space was defined as ‘inappropriate injection’. Pre‐ and postprocedure pain was assessed using a standard analog scale. Before and 2, 4, 8, 12, and 16 weeks after the procedure, pain scores were evaluated. From April 2003 to May 2005, 13 patients were enrolled in this study. Improvement of pain score in the ‘bilateral injection’ and ‘unilateral injection’ groups was significantly superior to the change in the ‘inappropriate injection’ group. Although EUS‐CPN was effective in eight of 13 patients (61.5%), additional EUS‐CPN to the ‘inappropriate injection group’ increased the response rate to 84.6%. Injection of ethanol to the anterocrural space by EUS‐CPN produced adequate pain relief. Immediate examination by CT for confirmation of injection sites after EUS‐CPN would increase the likelihood of induction of pain relief.  相似文献   
25.
AIM: The role of air plethysmography (APG) in the diagnosis of chronic venous insufficiency has not been well established. The purpose of this study was to elucidate the relationship between APG parameters and clinical severity in patients with chronic venous insufficiency. METHODS: Two hundred and ninety-four limbs in 154 patients with primary varicose veins were evaluated by APG. Limbs were categorized according to the clinical classification of chronic venous disease suggested by the Ad Hoc Committee on Reporting Standards in Venous Disease of the North American Chapter of the Society for Vascular Surgery and International Society for Cardiovascular Surgery (SVS/ ISCVS). RESULTS: The venous filling index (VFI) was significantly higher in classes 2, 3, 4, and 5+6 than in class 0 or 1, and did not differ among classes 2, 3, 4, 5+6. The ejection fraction did not differ significantly among the 6 classes, and the residual volume fraction was significantly higher in classes 2, 3, 5+6 than in class 0. CONCLUSIONS: APG is a reasonable method for distinguishing the presence or absence of chronic venous insufficiency, but it cannot discriminate the clinical severity. Among APG parameters, the VFI is the most useful diagnostic parameter in the evaluation of chronic venous insufficiency.  相似文献   
26.
The present study aimed to elucidate risk factors for nonimmunocompromised pulmonary Mycobacterium avium complex (MAC) infection. Epidemiological data and variations of candidate genes for mycobacterial diseases were analysed in 111 patients with pulmonary MAC infection. Four polymorphisms of the human natural resistance-associated macrophage protein (NRAMP)1 gene, the 5'(GT)n, 469+14 G/C, D543N and the 3'untranslated region (3'TGTG) insertion/deletion, were genotyped using PCR-based methods. Fok I and Taq I polymorphisms of the vitamin D receptor gene and -221 X/Y and codon 54 A/B polymorphisms of the mannose binding lectin gene were also evaluated. Females were more susceptible to MAC infection mainly affecting the right middle lobe or lingular segment of the lung. Patients' residence at the onset of the disease was distributed evenly irrespective of a waterfront or city water supply system. As compared with homozygotes for major alleles of the D543N and TGTG insertion/deletion polymorphism of the NRAMP1 gene, heterozygotes containing minor alleles were less often observed in MAC cases than in controls. This genetic effect was more significant in patients without comorbidity but not in patients with comorbidity. Other polymorphisms did not show any association with the MAC infection. The human natural resistance-associated macrophage protein 1 gene might be involved in susceptibility to pulmonary Mycobacterium avium complex infection.  相似文献   
27.
28.
Background: The aim of this study was to investigate the effects of two imidazoline-derived intravenous anesthetics, etomidate and midazolam, on vascular adenosine triphosphate-sensitive potassium (KATP) channel activity.

Methods: In isolated rat aorta, isometric tension was recorded to examine the anesthetic effects on vasodilator response to levcromakalim, a selective KATP channel opener. Using the patch clamp method, the anesthetic effects were also examined on the currents through (1) native vascular KATP channels, (2) recombinant KATP channels with different combinations of various types of inwardly rectifying potassium channel (Kir6.0 family: Kir6.1, 6.2) and sulfonylurea receptor (SUR1, 2A, 2B) subunits, (3) SUR-deficient channels derived from a truncated isoform of Kir6.2 subunit (Kir6.2[DELTA]C36 channels), and (4) mutant Kir6.2[DELTA]C36 channels with reduced sensitivity to adenosine triphosphate (Kir6.2[DELTA]C36-K185Q channels).

Results: Etomidate (>= 10-6 m), but not midazolam (up to 10-6 m), inhibited the levcromakalim-induced vasodilation, which was sensitive to glibenclamide (IC50: 7.21 x 10-8 m; maximum inhibitory concentration: 1.22 x 10-4 m). Etomidate (>= 3 x 10-6 m), but not midazolam (up to 10-4 m), inhibited the native KATP channel activity in both cell-attached and inside-out configurations with IC50 values of 1.68 x 10-5 m and 1.52 x 10-5 m, respectively. Etomidate (10-5 m) also inhibited the activity of various types of recombinant SUR/Kir6.0KATP channels, Kir6.2[DELTA]C36 channels, and Kir6.2[DELTA]C36-K185Q channels with equivalent potency.  相似文献   

29.
30.
The immunohistochemical distribution of CA19-9 in normal and tumor tissue of the kidney was investigated. CA19-9 was detected in the cytoplasm and apical surface of renal proximal tubules, distal tubules and uroepithelium of the renal pelvis. Eight of 28 renal cell carcinomas (29%) expressed CA19-9. CA19-9 was also detected in 2 cases of transitional cell carcinoma and 1 of 4 cases of Wilm's tumor, but not in angiomyolipoma. As the measurement of CA19-9 is widely used to detect gastrointestinal carcinoma, the expression of CA19-9 in normal and neoplastic kidney tissue might have some clinical significance.  相似文献   
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