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排序方式: 共有1310条查询结果,搜索用时 31 毫秒
1.
Symptomatic liver cyst: Special reference to surgical management   总被引:2,自引:0,他引:2  
We conducted a retrospective study of 14 patients with symptomatic liver cysts to evaluate current therapeutic interventions for this condition. Abdominal pain (n = 7) or abdominal mass (n = 5) were the most frequent presentations. Three patients also had renal cyst. Percutaneous aspiration with ethanol sclerotheraphy was carried out in 4 patients and all cysts so treated diminished in size, with relief of the symptoms. One patient was treated by aspiration only and re-retension occurred. Cystectomy was performed in 2 patients, unroofing in 5, and fenestration in 2 patients. All patients gained relief of symptoms, with no recurrence of symptoms. Computed tomography revealed that the cysts were diminished or were no longer observable after all the treatments. Our experience indicates that unroofing, fenestration, and cystectomy are safe and suitable procedures for treatment of the condition. Ethanol sclerotherapy may be a feasible alternative to surgical intervention in selected patients. Received for publication on July 23, 1997; accepted on Dec. 25, 1997  相似文献   
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Rat mesangial cells were shown to be sensitive to recombinant interferon-gamma (IFN-gamma). IFN-gamma reduced thymidine uptake by these cells and inhibited cell proliferation. Incubation of the cells with 1000 U/ml IFN-gamma decreased thymidine uptake by up to 64% and cell numbers were decreased by 17%. The effects of IFN-gamma were dose and time dependent and were partially reversible by the anti-IFN-gamma monoclonal antibody DB-1. This lymphokine did not reduce incorporation of RNA and protein precursors however. Measurements of 3H-uridine and 3H-leucine incorporation indicated significant increases in RNA and protein synthesis (37% and 45%, respectively) on a per cell basis. The mitogenic effects of IL-1 and platelet-derived growth factor (PDGF) were also susceptible to IFN-gamma-mediated inhibition but the mitogenic response to epidermal growth factor (EGF) was much less sensitive. We conclude that while IFN-gamma may act to modulate the mitogenic signals provided by some factors such as IL-1 and PDGF, the response to EGF appears to be unaffected.  相似文献   
4.
IgA deposition in the glomerular mesangial matrix is a prerequisite for the diagnosis of IgA nephropathy, and circulating IgA-containing complex has been implicated in this process. Since fibronectin is known to be involved in the assembly of extracellular matrix, this study was conducted to investigate whether fibronectin and its fragments are present in sera of patients and are capable of binding IgA1. Sera from patients with IgA nephropathy were purified by heparin-affinity chromatography, and column eluate were analyzed for the presence of fibronectin using Western blot and a set of anti-fibronectin monoclonal antibodies. Native fibronectin was digested with cathepsin D to obtain fragments similar to those of serum fibronectin. The capacity of fibronectin to bind IgA was examined with a mixture of purified IgA1 and cathepsin D-digested fibronectin fragments. A 43-kD carboxy-terminal fragment of fibronectin was detected in samples derived from sera of patients with IgA nephropathy but not in healthy control subjects. A similar-sized fragment was generated by cathepsin D digestion of the native molecule and was shown to bind to IgA1 in vitro. Since the carboxy-terminal domain is known to be critical in assembling exogenous fibronectin into the extracellular matrix, the affinity to IgA1 to a fragment found in patients may have pathogenic potential to mediate extracellular IgA deposition in IgA nephropathy.  相似文献   
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We investigated the effects of four ginseng saponins, ginsenoside-Rb1, -Rg2, -Rg3 and -Ro, on the responses induced by receptor stimulation of various stimuli. Ginsenoside-Rg2 (1-100 microM) reduced the secretions of catecholamines from bovine adrenal chromaffin cells stimulated by acetylcholine and gamma-aminobutyric acid but not by angiotensin II, bradykinin, histamine and neurotensin. In guinea-pig, the ginsenoside also diminished the nicotine-induced secretion of catecholamines from the adrenal chromaffin cells, but it did not affect the muscarine- and the histamine-induced ileum contractions. On the other hand, ginsenoside-Rg3 (1-100 microM) reduced not only the acetylcholine-, the gamma-aminobutyric acid- and the neurotensin-induced secretions but also, at a higher concentration (100 microM), the angiotensin II-, the bradykinin- and the histamine-induced secretions from the bovine chromaffin cells. Furthermore, the saponin (3-100 microM) significantly inhibited the muscarine- and the histamine-induced ileum contractions of the guinea-pig. Ginsenoside-Rb1 and -Ro had no marked effect on their responses. These results strongly suggest that ginsenoside-Rg2 is a potent selective blocker of nicotinic acetylcholine and gamma-aminobutyric acid receptors (ionotropic receptors) and ginsenoside-Rg3 is not only a blocker of ionotropic receptors but also an antagonist of muscarinic or histamine receptors.  相似文献   
7.
The intravenous secretin injection test (secretin test) has been used for the differential diagnosis of gastrinoma. In this study we report that the intraoperative secretin test (IOS test) is also useful for determining the extent of curability in patients with Zollinger-Ellison syndrome (ZES). Twelve patients with ZES underwent surgical exploration and the IOS test. The results of the IOS test were obtained by rapid radioimmunoassay of the serum gastrin level (IRG) within 60 minutes. The test was diagnosed as negative when the maximum increase of serum IRG was less than 80 pg/ml and also less than 20% of the basal serum IRG level. Three of the twelve patients underwent pancreatoduodenectomy (PD), and two patients underwent distal pancreatectomy. Extirpation of duodenal tumors with dissection of regional lymph nodes was performed in seven patients. In two of the seven patients the IOS test remained positive after extirpation of the duodenal tumors and the dissection of regional lymph nodes. In one patient PD was performed on the basis of the positive results, and the IOS test became negative after PD. In the other patient, two tiny metastatic liver tumors were identified and were resected, but the IOS test did not become negative. We closed the abdomen in 11 patients when we obtained negative results from the IOS test. The results of the IOS test were almost identical to the data obtained by the standard assay postoperatively. The serum IRG levels of all but one patient fell to the normal level, and the secretin test became negative postoperatively. The IOS test is thus useful and indispensable for curative resection of microgastrinomas in patients with ZES.  相似文献   
8.
We present a case of undifferentiated pancreatic cancer associated with humoral hypercalcemia of malignancy (HHM) in which parathyroid hormone-related protein (PTH-rP) is identified as the causative factor of hypercalcemia. A 61-year-old man was hospitalized with right hypochondralgia. Ultrasound examination and computed tomography demonstrated a large mass in the pancreatic head with liver metastases. Biopsy of the pancreatic tumor demonstrated undifferentiated carcinoma. Serum calcium level and PTH-rP were elevated. Bone scan with technetium-99 demonstrated no accumulation in the bones. Immunohistochemical staining for PTH-rP was weakly positive in the tumor cells. We considered that PTH-rP was the causative factor of HHM in this case from laboratory data and immunohistochemical findings. This rare case was successfully treated with pamidronate disodium, which is a type of bisphosphonate derivative. We compared this case with previously reported cases.   相似文献   
9.

Background  

Hepatocyte growth factor (HGF) is a potent growth factor involved in liver regeneration that has various effects on epithelial and nonepithelial cells. Although it has been demonstrated that HGF can reduce liver inflammation or fibrosis caused by pharmaceutical or chemical insult, no examination of its effect on liver injury in nonalcoholic steatohepatitis (NASH) has been reported.  相似文献   
10.

In the course to find compounds that inhibit melanin biosynthesis (i.e., whitening agents), we evaluated the effects of the methanol-soluble fraction (i.e., the water-soluble portion of methanol extracts-CHP20P-MeOH eluted fraction) from young green barley leaves on melanin production in B16 melanoma cells. Activity-guided fractionation led to an isolate called tricin (compound 1) as an inhibitory compound of melanin production in B16 melanoma cells. Furthermore, tricin analogs such as tricetin, tricetin trimethyl ether, luteolin, and apigenin were used for analyzing the structure–activity relationships (SAR) of 5,7-dihydroxyflavones studies. Tricin demonstrated stronger inhibitory activity compared to three other compounds. The results suggest that a hydroxyl group at the C-4′ position and methoxy groups at the C-3′,5′ positions of the tricin skeleton may have important roles in this inhibitory activity in B16 melanoma cells. Our results suggest that tricin inhibits melanin biosynthesis with higher efficacy than arbutin, and it could be used as a whitening agent.

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