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21.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
22.
OBJECTIVE: Many phase II trials have shown that preoperative chemotherapy for lung cancer is feasible but associated with postoperative morbidity and mortality. However, little is known about the effect of preoperative chemotherapy on surgical stress and postoperative complications associated with surgical intervention. We evaluated the effect of preoperative chemotherapy on perioperative inflammatory cytokine production as a surgical stress marker. METHODS: The study group comprised 38 patients undergoing anatomical lung resection and mediastinal nodal dissection for clinical stage IB/II non-small cell lung cancer during the period October 2001-December 2003. Nineteen patients received a single cycle of cisplatin (80 mg/m(2)) and docetaxel (60 mg/m(2)) chemotherapy prior to surgery (neoadjuvant group), and 19 patients underwent surgery without any previous chemotherapy (control group). White blood cell and neutrophil counts and serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), and granulocyte colony-stimulating factor (GCSF) were determined before surgery and on postoperative days 1 and 3. Postoperative complications were reviewed. Differences were assessed by repeated analysis of variance. RESULTS: Serum concentrations of IL-6 and GCSF rose significantly on postoperative days 1 and 3 in the neoadjuvant group in comparison to concentrations in the control group, but white blood cell count, neutrophil count, and CRP did not differ between the groups. No major complication occurred in either group. CONCLUSIONS: A single cycle of cisplatin and docetaxel chemotherapy followed by surgery can exacerbate overproduction of inflammatory cytokines during the perioperative period in lung cancer patients.  相似文献   
23.
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
24.
To examine the role of the apoptosis of macrophages and smooth muscle cells in the development of atherosclerosis, human aortic tissues with intimal lesions were immunostained with antibodies against terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL), single-stranded DNA (clone F7-26), and active caspase-3. Apoptotic cells were detected in the intima using both TUNEL and single-stranded DNA, however, the latter method was the more sensitive one for detecting apoptotic cells in the early stages of atherosclerosis. The number of apoptotic cells increased as the disease progressed. It implies that the apoptosis of intimal cells is involved in the formation of atherosclerotic lesions. In addition, quantitative analyses of the cell types undergoing apoptosis using double-immunostaining revealed that the susceptibility of macrophages and smooth muscle cells to apoptosis was greater specifically in atheroma than in the other atherosclerotic lesions, and macrophages were more susceptible to apoptosis than smooth muscle cells. The frequency and spatial distribution of oxidized low-density lipoprotein (oxLDL) (FOH1a/DLH3)-positive cells were examined by immunohistochemistry, and the results resembled those of apoptotic cells. The number of oxLDL-positive cells in the intima significantly correlated with the susceptibility of smooth muscle cells, but not with that of macrophages, to apoptosis. These results suggest that oxLDL affects the apoptosis of smooth muscle cells during the atherosclerotic development.  相似文献   
25.
The concentration of ceftazidime was determined in the aqueous humor and the vitreous body of normal, vitrectomized and aphakic/vitrectomized eyes and in the serum of albino rabbits 1 h after intravenous injection of 100 mg/kg ceftazidime. The intravitreal ceftazidime concentration was low (0.1-0.2 microgram/ml) in normal eyes 1 h after intravenous injection, and high (8.7 +/- 8.5 micrograms/ml) in vitrectomized and aphakic/vitrectomized eyes when injected immediately after surgery. The ceftazidime concentration was also determined in the aqueous humor and the vitreous body of normal eyes and in the serum of albino rabbits 3, 6, 12, 24 and 48 h after intravitreal injection of 200 micrograms. The intravitreal ceftazidime concentration after intravitreal injection decreased exponentially for 12 h (half-life about 7.4 h). It decreased more slowly thereafter and remained at 13.0 micrograms/ml (mean) even 48 h after injection. This concentration exceeded the minimum inhibitory concentrations against common gram-positive and gram-negative organisms causing endophthalmitis.  相似文献   
26.
We report an unusual case of a large inferior mesenteric-caval shunt in a 25-year-old man without cirrhosis with hypoproteinemia and hypochromic anemia. In this large shunt the direct communication was between the inferior mesenteric vein and the internal iliac vein. Hemodynamic change as a result of the shunt was thought to cause his present clinical problems and future portosystemic encephalopathy. Percutaneous transcatheter embolization of the shunt with fibrin glue was performed through the internal iliac vein, and this offered amelioration of hypoproteinemia and reduction of serum ammonia levels without any complications. An interventional radiologic approach instead of surgical ligation should be attempted for portosystemic shunts, and fibrin glue, as well as coils or a detachable balloon, is also valuable as an embolizing material.  相似文献   
27.
Liver transplantation, which serves as treatment of familial amyloidotic polyneuropathy (FAP), and domino liver transplantation, which utilizes resected livers from patients with FAP for treatment of liver diseases, may induce changes in transthyretin (TTR), a pathogenic FAP-related protein. To evaluate this possibility, we performed a 70% hepatectomy or administered tacrolimus to Dark Agouti (DA) rats for 7 days and then measured changes in liver TTR mRNA levels and changes in serum TTR concentrations. After hepatectomy, TTR mRNA levels decreased by 77%; at day 3, they returned to preoperative levels. Except for slightly elevated serum TTR concentrations 12 h after operation, serum TTR levels remained unchanged. Thus, partial hepatectomy did not influence serum TTR concentrations. After tacrolimus administration, TTR mRNA declined by 56% 12 h after the experiment started; however, after day 3, a rebound phenomenon occurred until day 7. Tacrolimus may facilitate serum TTR degradation, although production of TTR in the liver also increased. This finding -- that TTR, the source of FAP-inducing amyloid, did not increase after transplantation -- may help post-transplantation treatment of patients who have FAP and other liver diseases.  相似文献   
28.
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo.  相似文献   
29.
OBJECTIVE: NKH477 was recently identified as a water-soluble forskolin derivative and was reported to prolong survival of murine cardiac allografts. However, the mechanism of the efficacy is not clear in vivo. The aim of this study was to investigate the immunosuppressive effects of NKH477 on acute lung allograft rejection in the rat model and its mechanism of action in vivo. METHODS: Left lungs were transplanted orthotopically from Brown-Norway donors to Lewis recipients. Recipient rats were untreated or treated daily with different doses of NKH477. Grafts were excised on Day 3 or Day 5 to determine histopathological rejection and expressions of interleukin (IL)-2, IL-4, IL-10, and interferon (IFN)-gamma by enzyme-linked immunosorbent assay. The cytokine expression at Day 3 or Day 5 was also evaluated in recipient spleens by immunohistochemistry. Furthermore, mesenteric lymph node cells from recipients at Day 5 were cultured alone or stimulated with donor antigens for 72 hours to determine cell proliferation by means of thymidine incorporation. RESULTS: NKH477 significantly extended allograft survival time in a dose-dependent manner and reduced histopathological rejection. Treatment with NKH477 inhibited IFN-gamma and IL-10 expression, whereas expression of these cytokines were markedly upregulated in the untreated allografts. Expression of IL-2 and IL-10 also increased in the spleen of untreated allorecipients. NKH477 suppressed expression of both cytokines in the spleen. In addition, lymphocyte proliferation was inhibited in NKH477-treated recipients as compared with untreated recipients. CONCLUSION: These results suggest that NKH477 exerts an antiproliferative effect on lymphocytes in vivo with an altered cytokine profile in rat recipients of lung allografts.  相似文献   
30.
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion.  相似文献   
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