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1.
 Three further cases of mature benign cystic teratomas of the ovary associated with virilization are added to the three previously reported in the literature. They were found in postmenopausal, obese, diabetic women aged 52, 61, and 67 years. The patients presented with hirsutism and voice changes and clitoromegaly was present in one. Testosterone and androstenedione levels were elevated but promptly regressed after removal of the tumours. Histologically, sheets of stromal luteinized cells were found peripherally at the interface between the neoplasm and ovarian tissue. Luteinization of ovarian stroma induced by an unknown factor related to diabetes mellitus is the origin of the virilization. Received: 8 January 1997 / Accepted: 28 February 1997  相似文献   
2.
P-glycoprotein (P-gp) expels hydrophobic substances from the cell, including chemotherapeutic agents and immunosuppressants such as cyclosporin A (CsA) and FK506. Exposure of cultured renal tubular cells to CsA induces P-gp overexpression in cell membranes. Angiotensin II has recently been implicated as the principal factor responsible for progression of interstitial fibrosis induced by CsA. To investigate the in vivo relationships between histological lesions, P-gp overexpression, and intrarenal angiotensin II deposits, we developed a model of chronic CsA toxicity in Sprague-Dawley rats treated with 25 mg/kg/day CsA for 28 and 56 days and fed either a standard maintenance diet or a low-salt diet. Immunohistochemical methods were used to study the expression of P-gp in renal tubular cells and the appearance of intrarenal angiotensin II deposits. Rats treated with CsA developed chronic nephrotoxicity lesions that were more evident in the group fed the low-salt diet. Treatment with CsA induced overexpression of P-gp in tubular cells of the kidney that increased with time. We found that immunohistochemical expression of P-gp was slightly more severe in rats fed a low-salt diet. Intrarenal deposits of angiotensin II were more evident in rats treated with CsA; these deposits also increased with time. This finding was also more relevant in rats given the low-salt diet. The up-regulation of P-gp was inversely related to the incidence of hyaline arteriopathy (r = -0.65; P < 0.05), periglomerular (r = -0.58; P < 0.05) and peritubular fibrosis (r = -0.63; P < 0.05), and intrarenal angiotensin H deposits in animals with severe signs of nephrotoxicity (r = -0.65; P < 0.05). These results support the hypothesis that the role of P-gp as a detoxicant in renal cells may be related to mechanisms that control the cytoplasmic removal of both toxic metabolites from CsA and those originating from the catabolism of signal transduction proteins (methylcysteine esters), which are produced as a result of ras activation in presence of angiotensin II.  相似文献   
3.
Myxoid leiomyosarcoma of the ovary: Analysis of three cases   总被引:2,自引:0,他引:2  
The first three cases of myxoid leiomyosarcoma occurring in the ovary are reported. Two cases in stage III were found in postmenopausal patients and a further case was found in stage I in a 32-year-old. All masses were large and gelatinous with cystic change, necrosis, and hemorrhage, but both uteri and ligaments and contralateral adnexa appeared normal. Microscopically, the tumors showed a predominantly reticular meshwork of elongated cells surrounded by abundant basophilic material. While electron microscopy proved inconclusive due to nondifferentiation, the use of monoclonal antibodies against smooth muscle actin demonstrated a smooth muscle type of differentiation. The differential diagnosis of this rare ovarian condition includes other myxoid ovarian lesions, such as ovarian edema, myxoma, endodermal sinus tumors, and the sarcomatous component of malignant mixed müllerian tumor and carcinosarcoma, as well as lymphovascular tumors. Since mitotic count due to decreased cellular density is unusually low in myxoid leiomyosarcoma, capsular rupture and clinical stage seem to be more reliable prognostic markers. The highly aggressive behavior of myxoid leiomyosarcoma parallels that of typical ovarian leiomyosarcoma. Two of the three patients in this series died of tumor at 13 and 24 months after diagnosis; the other patient is free of disease at 3 years after diagnosis.  相似文献   
4.
Four cases of polyvesicular vitelline tumor are presented; two were of a previously unreported pure type, and the other two were mixed with endodermal sinus tumor.The morphologic features of the vesicles favor an endodermal origin, as originally proposed by Teilum. Marked specialization of the vesicular lining cells, seen ultrastructurally, suggests a differentiation toward gut structures and mature yolk sac. One case of pure polyvesicular vitelline tumor showed massive erythropoiesis. We propose that the pure tumor reflects an intermediate degree of differentiation within the selectively endodermal yolk sac tumor group, that is, a further stage of organization than the endodermal sinus tumor.In our cases of pure polyvesicular vitelline tumor, the marked degree of differentiation was correlated with an improved prognosis, as in the case of the possible homologue of this tumor, the yolk sac tumor of the infant testis. In contrast, the two cases of the tumor admixed with endodermal sinus tumor illustrated the low survival rate expected in the pure endodermal sinus tumor; in these cases the metastases had no polyvesicular component. Because of the significance of such a difference in prognosis we emphasize the importance of an accurate diagnosis, suggesting that a large number of sections be taken in order to demonstrate any endodermal sinus tumor component that may be present, and that the possibility of pure polyvesicular vitelline tumor always be considered in the differential diagnosis of multicystic ovarian tumors.  相似文献   
5.
Enhanced Recovery After Surgery (ERAS) constitutes the application of a series of perioperative measures based on the evidence, in order to achieve a better recovery of the patient and a decrease of the complications and the mortality. These ERAS programs initially proved their advantages in the field of colorectal surgery being progressively adopted by other surgical areas within the general surgery and other surgical specialties. The main excluding factor for the application of such programs has been the urgent clinical presentation, which has caused that despite the large volume of existing literature on ERAS in elective surgery, there are few studies that have investigated the effectiveness of these programs in surgical patients in emergencies. The aim of this article is to show ERAS measures currently available according to the existing evidence for emergency surgery.  相似文献   
6.
Predator activity around the nests induces stress in breeding birds, which may have weaker immunity and are therefore more susceptible to parasite infections. The influence of predators on parasites has only been observed in land birds, and most studies are experimental. As seabird colonies offer excellent conditions for parasites, here we assess the influence of mouse, rat, and cat activity on parasites in Cory's shearwater (Calonectris diomedea borealis). Adults were examined for blood parasites and one adult and the juvenile from 53 nests were inspected for ectoparasites over two consecutive years (2010 and 2011). Nests differed in their physical characteristics and indices of mammal predator activity and were checked weekly to assess breeding success. Our results showed absence of blood parasites. Among the environmental factors, predator pressure received the most support (89 %) from the data as influencing nest ectoparasite intensity. Birds most infected had worse body condition, and breeding success was negatively influenced by predator activity and ectoparasite intensity. To our knowledge, this is the first analysis of the interaction between mammal predators and ectoparasites in seabird species and supports greater protection through eradication efforts. In addition, we provide the first data on the endoparasite fauna of Cory's shearwater.  相似文献   
7.
8.
The presence of acute fluid collections is an habitual event in an acute pancreatitis, generally followed by a favourable outcome. We present a case about an ancient woman suffering from an acute necrotizing pancreatitis with tense fluid collections that produced espontaneously several cutaneous fistula. We find no report on literature about this uncommon complication. We revised clinical management of acute fluid collections and pancreatic fistulas.  相似文献   
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10.
Background: We assessed the still unclear effect of the overall alcohol-drinking pattern, beyond the amount of alcohol consumed, on the incidence of cardiovascular clinical disease (CVD). Methods: We followed 14,651 participants during up to 14 years. We built a score assessing simultaneously seven dimensions of alcohol consumption to capture the conformity to a traditional Mediterranean alcohol-drinking pattern (MADP). It positively scored moderate alcohol intake, alcohol intake spread out over the week, low spirit consumption, preference for wine, red wine consumption, wine consumed during meals and avoidance of binge drinking. Results: During 142,177 person-years of follow-up, 127 incident cases of CVD (myocardial infarction, stroke or cardiovascular mortality) were identified. Compared with the category of better conformity with the MADP, the low-adherence group exhibited a non-significantly higher risk (HR) of total CVD ((95% CI) = 1.55 (0.58–4.16)). This direct association with a departure from the traditional MADP was even stronger for cardiovascular mortality (HR (95% CI) = 3.35 (0.77–14.5)). Nevertheless, all these associations were statistically non-significant. Conclusion: Better conformity with the MADP seemed to be associated with lower cardiovascular risk in most point estimates; however, no significant results were found and more powered studies are needed to clarify the role of the MADP on CVD.  相似文献   
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