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The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
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We report two cases of a rare benign tumour of hair germ. Clinically, both were solitary, well-circumscribed, subcutaneous nodules located in the extremities. Histologically, the tumours were characterized by nests and thin cords of basaloid epithelial cells intimately associated with a cellular stroma. The basaloid cells exhibited peripheral palisading, keratinization in the form of keratotic cysts and squamoid transformation, and pilar differentiation. An unusual, but distinctive, cribriform pattern of growth was observed. There was no communication with the overlying epidermis. Abundant primitive hair germinal buds and rare more advanced abortive hair follicles were identified. These histological appearances encompass features of both trichoblastic fibroma and trichogenic trichoblastoma, thus distinguishing these neoplasms from other skin tumours and reinforcing the hypothesis that these tumours are closely related from a histogenetic point of view. The presence of overlapping histological features can be problematic for practising histopathologists who rarely encounter these conditions. With this in mind, the term benign trichogenic tumour may be more appropriate to encompass these two tumours and related neoplasms that appear to lie within the spectrum of hair follicle development.  相似文献   
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Expression of cadherins and CD44 isoforms in ovarian endometrial cysts   总被引:3,自引:0,他引:3  
We evaluated the immunohistochemical expression of cadherins and CD44 variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian tumours as well as 20 ovarian carcinomas, and the serological and cystic fluid concentrations of soluble E-cadherin and soluble CD44 standard (sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11 carcinomas of the ovary. In endometriomas, immunostaining of E- and N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6 immunostaining were detected in 63, 10 and 40% respectively. A difference in immunostaining for E-cadherin was found between endometriomas and cystadenomas (P < 0.001) and for N- cadherin between endometriomas and carcinomas (P < 0.001). A difference in CD44H immunostaining was observed between endometriomas and cystadenomas (P < 0.035) but not with borderline ovarian tumours and carcinomas. No difference in serum concentrations of soluble E- cadherins and CD44 standard was found between the four groups of tumours. Cystic fluid concentrations of E-cadherin were lower in endometriomas than in borderline tumours and ovarian carcinomas (P < 0.001). High concentrations of soluble CD44 standard cystic fluid were found in endometriomas than in other ovarian cysts. Endometriomas and borderline tumours share alterations of cadherins and CD44 isoforms which may help in the understanding of the aggressive and invasive potentials of endometriotic cells.   相似文献   
7.
Genital asymmetry in men   总被引:1,自引:0,他引:1  
This study examined genital asymmetry in a large sample of men. The probands were 6544 non-delinquent men who were interviewed by the Kinsey Institute for Research in Sex, Gender and Reproduction from 1938 to 1963. The measures were four indicators of penile and scrotal asymmetry, along with self-reported handedness, from Kinsey's interview protocol. Most men reported some degree of lateral asymmetry in their flaccid penis and in their testicles; less asymmetry was reported for their erect penis. The asymmetry typically occurred in the left direction, and this pattern occurred in both right- and nonright- handers. However, this 'leftward' pattern was significantly less pronounced in nonright-handers. The results are discussed in relation to previous findings of genital asymmetry in men, the possible relationship of genital asymmetry to functional cerebral asymmetry, and recent data suggesting genital asymmetry may predict patterns of cognitive performance and genital/sexual organ cancers.   相似文献   
8.
The main metabolic pathway for the interstitial matrix component hyaluronan seems to be via lymph. Present estimates of turnover of intestinal hyaluronan are based on isolated organs and/or experiments in anaesthesia over a few hours. In this study lymph was sampled from the main mesenteric lymphatic for 24 h in awake, restrained rats. The tissue content of hyaluronan averaged 28 /μ g-1 in the duodenum/jejunum and 124 μ g-1 in the colon. Based on tissue content and lymphatic output, the turnover rate of hyaluronan in the small intestine was estimated at approximately 50%. In another experimental group anaesthetized rats were fed either phosphate buffer or triolein in buffer via a gastric tube. Lymph flow increased with fluid absorption from the gut and hyaluronan output in lymph was elevated correspondingly. However, no effect of acute fat administration on hyaluronan concentration or lymph flow could be demonstrated.  相似文献   
9.
A symposium entitled Impact of Nutrients on Cellular Lipid Peroxidationand Antioxidant Defense System was held at the 33rd Annual Meetingof the Society of Toxicology (SOT) at the Loews Anatole Hotelin Dallas, Texas. The symposium was sponsored by the Food SafetySpecialty Section and focused on the role of particular nutrientsin cellular lipid peroxidation and antioxidant defense system.Emphasis was placed on defining underlying mechanisms for damageand protection, as well as potential ramification in human healthissues. The following are extractions of some of the highlightsfrom each presentation.  相似文献   
10.
Immune deficiencies in chronic intestinal pseudo-obstruction   总被引:1,自引:0,他引:1  
Aim: Chronic intestinal pseudo-obstruction has been associated with urinary disorders, myopathy, and ophthalmoplegia in adults and cholelithiasis in children. We observed a high percentage of total-parenteral-nutrition-dependent patients with pseudo-obstruction and recurrent infections requiring gammaglobulin infusions. Methods: AH records for 23 children with chronic intestinal pseudo-obstruction (10 females and 13 males, mean age 9.8 y ± 4.9 y, range 4–24 y) referred for a nutritional evaluation from 1992 to 1995 were reviewed. Chronic intestinal pseudo-obstruction was diagnosed by clinical, radiographic findings and antroduodenal manometry. Intestinal full-thickness biopsies were performed in seven children. Results: Hypogammaglobulinemia was diagnosed in 18 patients (78%): 16 patients had various immunoglobulin deficiencies and 2 had selective antibody deficiency. Intravenous gammaglobulin was administered in 14 patients. Other medical conditions affecting the children are summarized as follows: autonomic dysfunction in 10 patients (43%), recurrent hypoglycemia in 9 (39%), asthma in 9 (39%), cholecystitis in 7 (30%), low serum carnitine level in 6 (26%), urinary dysfunction in 6 (26%), pancreatitis in 5 (22%), behavioral problems in 5 (22%), myopathy in 2 (9%), idiopathic thrombocytopenia in 2 (8%), velopharyngeal insufficiency in 1 (4%), oculocutaneous albinism in 1 (4%), Pierre-Robin syndrome in 1 (4%), and protein C deficiency in 1 (4%). Munchausen syndrome was suspected in two patients. Conclusions: Chronic intestinal pseudo-obstruction appears to be associated with immune deficiencies. It is unclear if the immune deficiencies, intestinal pseudo-obstruction, and the other medical conditions have a common underlying etiology. Repeated infections may be due to impaired immune function in children with chronic intestinal pseudo-obstruction. We recommend screening for immune deficiencies in children with chronic intestinal pseudo-obstruction.  相似文献   
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