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排序方式: 共有698条查询结果,搜索用时 21 毫秒
1.
2.
Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
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
3.
Darai E; Leblanc M; Walker-Combrouze F; Bringuier AF; Madelenat P; Scoazec JY 《Human reproduction (Oxford, England)》1998,13(5):1346-1352
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
4.
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
5.
6.
van Asperen J van Tellingen O Schinkel AH Beijnen JH 《The Journal of pharmacology and experimental therapeutics》1999,289(1):329-333
To determine the tissue-specific impact of P-glycoprotein on the accumulation of a substrate drug, we have studied the tissue distribution of vinblastine in mdr1a(-/-) and wild-type mice at approximately similar, relatively low plasma levels. Vinblastine was administered as a 96-h continuous infusion at dose rates of 1 to 10 microgram/h, which were delivered by a s.c.-implanted osmotic pump. Drug concentrations were determined in plasma and tissues by HPLC. In comparison to wild-type mice, 4.4- to 9.6-fold higher drug concentrations were observed in the brains of mdr1a(-/-) mice (p =. 014), whereas a 2-fold increase was found in the heart (p =.014) and the intestinal tissues (p =.028). No or only slight differences were observed in all other tissues. These results indicate that, except for the brain and, to a lesser extent, the heart and the intestinal tissues, P-glycoprotein does not protect individual organs against vinblastine. Given its polarized cell-specific and organ-specific distribution and its affinity for a broad range of compounds, it is suggested that P-glycoprotein has mainly evolved to provide a general protection of the complete organism against potentially toxic substrates by inhibiting their uptake and by mediating their transport from the internal to the external environment. For the clinical application of reversal agents, these data indicate that, in general, a blockade of endogenous P-glycoprotein will probably not result in an increased accumulation of the coadministered anticancer drug in complete organs, but, possibly, only in classes of cells making up a fraction of an organ. 相似文献
7.
J W Jonker E Wagenaar L van Deemter R Gottschlich H M Bender J Dasenbrock A H Schinkel 《British journal of pharmacology》1999,127(1):43-50
Studies with knockout mice lacking mdr1a P-glycoprotein (P-gp) have previously shown that blood-brain barrier P-gp is important in preventing the accumulation of several drugs in the brain. Asimadoline (EMD 61753) is a peripherally selective kappa-opioid receptor agonist which is under development as a therapeutic analgaesic. From the structural characteristics of this drug and its peripheral selectivity, we hypothesized that it is transported by P-gp. Using a pig-kidney polarized epithelial cell line transfected with mdr cDNAs, we demonstrate that asimadoline is transported by the mouse mdr1a P-gp and the human MDR1 P-gp. Furthermore, we show that in mdr1a/1b double knockout mice, the absence of P-gp leads to a 9 fold increased accumulation of asimadoline in the brain. In line with this accumulation difference, mdr1a/1b (-/-) mice are at least 8 fold more sensitive to the sedative effect of asimadoline than wild-type mice. Interestingly, the oral uptake of asimadoline was not substantially altered in mdr1a/1b (-/-) mice. Our results demonstrate that for some drugs, P-gp in the blood-brain barrier can have a therapeutically beneficial effect by limiting brain penetration, whereas at the same time intestinal P-gp is not a significant impediment to oral uptake of the drug. 相似文献
8.
Schinkel AH 《Advanced drug delivery reviews》1999,36(2-3):179-194
The blood-brain barrier is a major impediment to the entry of many therapeutic drugs into the brain. P-Glycoprotein is an ATP-dependent drug transport protein that is predominantly found in the apical membranes of a number of epithelial cell types in the body, including the blood luminal membrane of the brain capillary endothelial cells that make up the blood-brain barrier. Since P-glycoprotein can actively transport a huge variety of hydrophobic amphipathic drugs out of the cell, it was hypothesized that it might be responsible for the very poor penetration of many relatively large (>400 Da) hydrophobic drugs in the brain, by performing active back-transport of these drugs to the blood. Extensive experiments with in vitro models and with knockout mice lacking blood-brain barrier P-glycoprotein or other animal models treated with blockers of P-glycoprotein have fully confirmed this hypothesis. Absence of functional P-glycoprotein in the blood-brain barrier leads to highly increased brain penetration of a number of important drugs. Depending on the pharmacological target of these drugs in the central nervous system (CNS), this can result in dramatically increased neurotoxicity, or fundamentally altered pharmacological effects of the drug. Given the variety of drugs affected by P-glycoprotein transport, it may be of tremendous therapeutic value to apply these insights to the development of drugs that should have either very poor or very good brain penetration, whichever is preferred for pharmacotherapeutic purposes. The clinical application of P-glycoprotein blockers should also be considered in order to improve the blood-brain barrier permeability of certain drugs that currently display insufficient brain penetration for effective therapy. 相似文献
9.
Immune deficiencies in chronic intestinal pseudo-obstruction 总被引:1,自引:0,他引:1
ML Forchielli MC Young AF Flores D. Richardson CW Lo 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(10):1077-1081
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
10.
Complications from improperly placed biliary stents are not uncommon. Free loose wires from the ends of an uncovered stent can irritate and damage adjacent mucosal surfaces. Effective management can be achieved via percutaneous placement of a second stent to alter the orientation of the original stent. 相似文献