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11.
The long term performance of various pacing leads in use for at least one year is reported from one centre. Between January 1975 and December 1990, 1056 cardiac pacing leads were implanted in 881 patients (mean age 57 +/- 13 years). Eight hundred and three leads were silicone insulated (SI) and 253 leads were polyurethane insulated (PUI). Leads from different manufacturers were used (Medtronic, CPI, Telectronics). The average duration of follow up was 56.6 +/- 77 months (range 12-221 months) for SI and 47.1 +/- 24 months (range 12-99 months) for PUI leads. Overall lead failure occurred more often in the PUI group (n = 46, 18.2%) compared to SI group (n = 93, 11.3%, p < 0.025). Majority of lead failures occurred in the first 36 months after implantation. In particular, Medtronic models 6971, 6972 (urethane) and 6901 (silicone) showed higher rate of complications (25.5%, 26.3% and 44.5% respectively).  相似文献   
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Totally extra-peritoneal (TEP) laparoscopic repair of an inguinalhernia involves the creation of an extra-peritoneal space by blunt dissection or the use of commercial balloons. This new technique demonstrates the use of a device to create this extra-peritoneal space, without the need for any commercial balloons. The extra-peritoneal space was created using a glove-balloon. A total of 107 consecutive TEP repairs were carried out using the glove-balloon technique, these included ten bilateral and 17 recurrent inguinal hernias. This method is simple, cost-effective and easy to teach.  相似文献   
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Malignancies of the middle ear and mastoid are rare and secondaries in the ear are extremely rare. A rare case of metastic adenocarcinoma from the breast is presented herewith.  相似文献   
16.
The effect of melanotropin release inhibiting factor (Pro-Leu-Gly-NH2, MIF) was determined on changes induced by two neuroleptics, haloperidol and centbutindole, in cerebral cortical 5-hydroxytryptamine (5-HT) receptors. Male Sprague-Dawley rats were injected daily i.p. with vehicle, haloperidol (1.0 mg/kg) or centbutindole (0.5 mg/kg), respectively, for 21 days. On day 22, these 3 groups were further divided into 2 subgroups and injected with either vehicle or MIF (2.0 mg/kg, i.p.) daily for 3 days. 3H-5-HT was used to study 5-HT1 receptors, and 3H-spiroperidol to label 5-HT2 receptors in the cerebral cortex. Chronic administration of haloperidol significantly increased (39.7%) the maximal binding capacity (Bmax) of 3H-5-HT binding to 5-HT1 receptors. Dissociation constant (Kd) values did not change. Centbutindole had no effect on 5-HT1 receptors. MIF had no effect on 5-HT1 receptors, nor did it alter haloperidol-induced increases in the Bmax of 3H-5-HT binding to 5-HT1 receptors. Chronic administration of centbutindole significantly increased (61.1%) the Bmax of 3H-spiroperidol binding to 5-HT2 receptors. No change occurred in the Kd values. Chronic treatment with haloperidol had no effect on 5-HT2 receptor characteristics. MIF had no effect on 5-HT2 receptors or on the increase in 5-HT2 receptor density induced by centbutindole. The behavioral syndrome induced by 5-hydroxytryptophan (5-HTP) (50, 100 and 200 mg/kg, i.p.) was also measured in rats treated chronically with haloperidol or centbutindole. Haloperidol had no effect on the 5-HTP syndrome, whereas centbutindole stimulated by 24-45% the intensity of the syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
17.
Spondyloenchondrodysplasia comprises generalized enchondromatosis with platyspondyly and is thought to be inherited as an autosomal recessive condition. A mother and son are reported with typical features of spondyloenchondrodysplasia. Their similar radiographic and MRI findings are presented. The radiologic appearance of the spine changed over time, illustrating the evolving phenotype of this condition. Transmission from mother to son suggests that dominant pattern of inheritance is possible. A classification of the enchondromatoses is discussed.  相似文献   
18.
To determine whether liver repopulation with cell transplantation could be of therapeutic value in acute hepatic failure, it is necessary to establish the fate of transplanted hepatocytes. This study used dipeptidyl peptidase IV-deficient F344 rats as recipients to analyse the engraftment and proliferation of transplanted hepatocytes. Syngeneic hepatocytes were transplanted intrasplenically 24-30 h after induction of liver injury by D-galactosamine (GalN). Portosystemic shunting was analysed with 99m-Tc-labelled albumin microspheres. GalN-treated rats showed characteristic hepatic necrosis, inflammation, gamma-glutamyl transpeptidase activation, and regenerative activity, without increased portosystemic shunting (>99% 99m-Tc activity was in the liver in normal and GalN-treated rats). Transplanted cells entered hepatic sinusoids promptly and were observed in liver plates at 48 h. The number of transplanted cells increased in GalN-treated rats by approximately seven-fold (range two- to 12-fold), along with evidence for DNA synthesis between 3 and 14 days after cell transplantation and greater prevalence of larger transplanted cell clusters. These findings indicate that the liver can be safely repopulated in animals with acute liver failure, although the time required for regenesis of plasma membrane structures and proliferation in transplanted hepatocytes will need to be considered in developing therapeutic strategies.  相似文献   
19.
Although there are ever increasing reports of extraintestinal human infections caused by Aeromonads, in both immunocompromised and immunocompetent patients, respiratory tract infections remain uncommon. We describe a case of aspiration pneumonia in an immunocompetent patient with multiple sclerosis, caused by a community acquired, multidrug resistant strain of Aeromonas hydrophila sensitive only to meropenem. The case highlights the clinical significance of Aeromonas hydrophila as a respiratory pathogen, as well as the community origin of multidrug resistance and the utility of newer carbapenems in such cases.  相似文献   
20.
The human epidermal growth factor receptor (HER) family of receptor tyrosine kinase has been extensively studied in breast cancer; however, systematic studies of EGFR gene amplification and protein overexpression in breast carcinoma are lacking. We studied EGFR gene amplification by chromogenic in situ hybridization (CISH) and protein expression by immunohistochemistry in 175 breast carcinomas, using tissue microarrays. Tumors with >5 EGFR gene copies per nucleus were interpreted as positive for gene amplification. Protein overexpression was scored according to standardized criteria originally developed for HER-2. EGFR mRNA levels, as measured by Affymetrix U133 Gene Chip microarray hybridization, were available in 63 of these tumors. HER-2 gene amplification by fluorescence in situ hybridization (FISH) and protein overexpression by immunohistochemistry were also studied. EGFR gene amplification (copy number range: 7-18; median: 12) was detected in 11/175 (6%) tumors, and protein overexpression was found in 13/175 (7%) tumors. Of the 11 tumors, 10 (91%) with gene amplification also showed EGFR protein overexpression (2+ or 3+ by immunohistochemistry). The EGFR mRNA level, based on Affymetrix U133 chip hybridization data, was increased relative to other breast cancer samples in three of the five tumors showing gene amplification. Exons 19 and 21 of EGFR, the sites of hotspot mutations in lung adenocarcinomas, were screened in the 11 EGFR-amplified tumors but no mutations were found. Three of these 11 tumors also showed HER-2 overexpression and gene amplification. Approximately 6% of breast carcinomas show EGFR amplification with EGFR protein overexpression and may be candidates for trials of EGFR-targeted antibodies or small inhibitory molecules.  相似文献   
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