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991.
Several nonsteroidal estrogens, such as ORF 3858 and F6103, which inhibit pregnancy in experimental animals when given postcoitally, have been previously described. ORF 8511 (1-diphenylmethylenyl-2-methyl-3-ethyl-4-acetoxycyclohexane) which is structurally similar to these compounds was studied for its postcoital antifertility activity and estrogenicity in rats, hamsters, mice and rabbits. Results of these studies suggest a relationship between these two biological endpoints. ORF 8511 produced uterotropic stimulation in the rat at microgram doses and totally inhibited implantation at 250 μg/kg/day administered on days 1–6 of pregnancy. However, the other species were considerably less sensitive to the compound with respect to both parameters. The compound stimulated tubal transport in rats at its minimum effective dose for antifertility activity as did diethylstilbestrol, a known estrogen. In the hamster, a species relatively insensitive to the antifertility effect of ORF 8511, endogenous estrogen titres during early pregnancy were higher than those in the rat. These data suggest that ORF 8511 and similar nonsteroidal compounds may owe their postcoital antifertility activity to their estrogenicity and that estrogens may act as pharmacological agents only in species with low normal endogenous estrogen titres. 相似文献
992.
Posterior peritoneal recesses: assessment using CT 总被引:3,自引:0,他引:3
Intraperitoneal compartments may extend posteriorly to the level of known retroperitoneal structures at several locations within the abdomen. These locations include the posterior subhepatic or hepatorenal space, the splenorenal space, the retropancreatic recess, the paracolic gutters, and the pararectal fossae. Because of their posterior location, fluid collections within these compartments may be mistaken radiologically for retroperitoneal masses. The sectional anatomy of these spaces, and particularly their appearance on computed tomographic scans, are illustrated in this paper. 相似文献
993.
The urinary bladder, obliterated umbilical arteries, and inferior epigastric vessels located within the extraperitoneal space of the anterior abdominal wall indent the anterior parietal peritoneum, forming intraperitoneal paravesical fossae. These are the supravesical space and the medial and lateral inguinal fossae. More posteriorly, the peritoneum covering the bladder is reflected onto the rectum to form the rectovesical space, which is divided by the uterus into an anterior vesicouterine recess and a posterior rectouterine pouch, or cul-de-sac. The cul-de-sac is continuous with the pararectal and ovarian fossae and is bounded posterolaterally by the rectouterine (sacrogenital) folds. These peritoneal compartments form a large potential space for the accumulation of ascites and are separated from the equally large extraperitoneal paravesical spaces by only a thin layer of peritoneum or peritoneum and umbilicovesical fascia. The computed tomographic scans of 100 patients with ascites were reviewed, with particular attention to the differentiation between intraperitoneal and extraperitoneal paravesical collections. The scans of intraperitoneal collections were found to have certain characteristic appearances, including inferior displacement of the distended urinary bladder, visualization of the umbilical folds, and preservation of the preperitoneal fat. 相似文献
994.
995.
Percutaneous enterostomy with the Cope suture anchor 总被引:2,自引:0,他引:2
996.
997.
To determine the optimal site for antegrade puncture of the femoral artery, the authors evaluated three cadaver specimens and computed tomographic (CT) scans of 50 patients. The relationships among the common femoral artery, the femoral artery bifurcation, the center of the femoral head, and the inguinal ligament were evaluated. CT showed that the center of the femoral head was always located caudal to the level of the inguinal ligament but cranial to the bifurcation of the common femoral artery. Therefore, the femoral head seems to provide a reliable landmark for entering the common femoral artery. 相似文献
998.
Acute cholecystitis: diagnostic accuracy of percutaneous aspiration of the gallbladder 总被引:1,自引:0,他引:1
Results of gallbladder bile aspiration and culture were correlated with presence or absence of acute cholecystitis in 36 patients to test the role of these procedures in hospitalized patients with sepsis. Diagnostic aspiration of the gallbladder was performed in 11 patients, and in the remaining patients a combination of percutaneous aspiration, percutaneous cholecystostomy, or cholecystectomy was used. Bile culture was not helpful in the prediction of acute cholecystitis, since results were not available for a minimum of 24-48 hours after aspiration. In addition, gram-stained smears and bile cultures suffered from low sensitivity (48% and 38%, respectively); consequently, a negative test does not allow the diagnosis of acute cholecystitis to be excluded. Bile aspiration of the gallbladder thus has a limited role in the diagnosis of this condition. 相似文献
999.
Twenty percutaneous transluminal angioplasty (PTA) procedures and 13 percutaneous venous embolization (PVE) procedures were performed in 23 patients who either had or were at risk for the development of recurrent bleeding, hepatic encephalopathy, or both after surgical shunt placement for portal hypertension. PTA, performed in 12 patients with significant shunt stenoses, resulted in reduction or elimination of gradients in all patients; rebleeding has occurred in only one patient. Complications consisted of one fatal rupture of a mesocaval interposition vein graft and one balloon rupture requiring surgical removal. PVE, performed in 11 patients, resulted in measurable improvement in four of seven encephalopathic patients and temporary control in the two patients with intractable bleeding. Three patients underwent PVE prophylactically. PTA of graft strictures is a valuable treatment modality. Embolization may be helpful in selected cases of hepatic encephalopathy. 相似文献
1000.