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Background: The Lichtenstein technique for inguinal hernia repair is easy to learn and associated with few complications. However, recent studies have suggested that this technique is inferior to some ‘sutureless’ repair systems in terms of perceived difficulty, operating time, surgeon satisfaction, etc. Methods: We employed a sutureless Lichtenstein technique in 80 consecutive patients with primary unilateral inguinal hernia, to assess patient and trainee surgeon outcomes. Human fibrin glue was used in place of conventional sutures. Results: The mean operating time was 36 min and all patients were discharged 5–6 h after the operation. On a 100-point visual analogue scale, the surgeons rated the difficulty of the operation as low (mean score, 31), and perceived satisfaction as high (mean score, 84). No complications were observed at 12-month follow-up. Conclusion: This study confirms the efficacy of mesh fixation with human fibrin glue, and supports the viability of a sutureless Lichtenstein procedure.  相似文献   
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We have used quantitative light microscopic autoradiographic techniques to analyze changes in muscarinic cholinergic receptors in the hippocampus in Alzheimer type dementia (ATD). The density and distribution of muscarinic cholinergic receptors has been correlated with the density of neurons, neuritic plaques and neurofibrillary tangles in the CA1 subfield of the hippocampus of control and ATD patients. The number of pyramidal cells per mm2 in the CA1 sector was significantly decreased in ATD cases as compared to controls, although there were large variations among cases. The most marked reductions in cell counts were observed in patients with a history of profound dementia. The densities of muscarinic receptors, as well as the proportions of M1 and M2 subtypes, in the CA1 sector and dentate gyrus were not significantly different between ATD and old non-demented patients. Neuritic plaques, even in high numbers, did not affect the density of muscarinic receptors; moreover, the densities of receptors over the neuritic plaques did not differ from the surrounding neuropil. However, in some ATD cases there was a marked decrease in the concentration of these receptors in the CA1 sector and subiculum, with no change in the proportions of muscarinic receptor subtypes. These patients exhibited frequent extracellular remnants of neurofibrillary tangles (ghost tangles), but scarce neuritic plaques, and were those showing severe losses of pyramidal cells. There was a significant positive correlation between the total concentration of muscarinic receptors in the CA1 and the density of pyramidal cells, suggesting that decreases in receptor concentration result from a severe neuronal loss. We observed that the ratio of muscarinic receptors per pyramidal cell was significantly increased in ATD patients. This might indicate a possible upregulatory mechanism for muscarinic receptors in the population of remaining neurons in ATD. However, decreases of receptor numbers following severe neuronal fall out suggest that compensatory mechanisms are no longer possible in such cases. The question is raised whether these differences between cases reflect different diseases or different stages of the same disease.  相似文献   
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Seasonal effects on hormonal and seminal parameters in subfertile stallions have not been well documented and could provide information that is needed to understand the underlying endocrine mechanisms associated with testicular dysfunction. Such information may be useful in developing diagnostic tools to identify those stallions who are candidates for treatment. This investigation characterizes and compares the effects of season on endocrine function and seminal quality in fertile and subfertile stallions. Eight fertile and six subfertile stallions between the ages of 5 and 18 years were injected intravenously once every hour for 3 hours with either 1 mL saline on the first experimental day or 5 micrograms gonadotropin-releasing hormone in 1 mL saline on the second experimental day during the nonbreeding and breeding season. Heparinized blood samples were collected periodically through a jugular catheter before and after treatment for analysis of luteinizing hormone, follicle-stimulating hormone, testosterone, and estrogen conjugates by radioimmunoassay. Semen samples were collected twice, 1 hour apart, from all stallions in both seasons for analysis of volume, concentration, motility, pH, and morphology. A series of low intravenous doses (5 micrograms) of gonadotropin-releasing hormone induced a significant luteinizing hormone response (P less than 0.05) compared with saline treatment in both fertile and subfertile stallions. Fertile stallions had a twofold higher (P less than 0.05) net increase in plasma luteinizing hormone levels (peak levels minus baseline levels) in the breeding seasons than in the nonbreeding season. The magnitude of the luteinizing hormone response relative to baseline levels in fertile stallions, however, was one-and-one-half times greater (P less than 0.05) in the nonbreeding season than in the breeding season. In contrast, season did not have an effect on the net increase in plasma luteinizing hormone or the magnitude of the luteinizing hormone response relative to baseline levels in subfertile stallions. The net increase in plasma luteinizing hormone was similar between the two groups of stallions in both seasons. The magnitude of luteinizing hormone response relative to baseline levels, however, was lower (P less than 0.05) in subfertile stallions (141 +/- 14%) than in fertile stallions (235 +/- 46%) in the nonbreeding season; the two groups exhibited similar responses in the breeding season. Compared with fertile stallions, subfertile stallions had twofold to fourfold higher (P less than 0.05) plasma levels of gonadotropins and similar testosterone levels. The number of total progressively motile sperm was lower (P less than 0.05) in subfertile stallions in both seasons.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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OBJECTIVE: To evaluate the mid-term results of endovascular stent-grafting for type B aortic dissection, in comparison with those of standard medical therapy in uncomplicated cases. METHODS: Between January 1999 and 2004, among 56 patients (mean age 59.5+/-11.5 years) with type B aortic dissection, hypotensive medical therapy was the only treatment in 28 uncomplicated cases, (group A), while stent-graft implantation was performed in 28 patients with uncontrolled hypertension, persistent pain or evidence of dissection progression or complication (group B). In 14 cases (50%) the procedure was performed in an acute setting. Stent-grafting procedures were monitored with intraoperative trans-esophageal echocardiography and cine-angiography. CT scan and trans-esophageal echocardiography were performed before hospital discharge, at 6 and 12 months and then yearly. RESULTS: Follow-up (range 1-61 months, average 18.1+/-16.9 months) was 100% complete. In-hospital mortality was 10.7% (three patients, all belonging to Group B; P=0.24). No spinal cord injuries were observed. Early endoleak occurred in one patient (3.5%). Mid-term mortality was lower in Group B, although the difference was not significant (10.7 versus 14.3% in Group A, P=0.71). Follow-up CT scans evidenced complete thrombosis of the false lumen in 75% cases in Group B, 10.7% in Group A (P=0.0001), and an aneurismal dilatation of the descending aorta in 3.5% cases in Group B, 28.5% in Group A (P=0.02). CONCLUSIONS: Although with still considerable early mortality, endovascular stent-graft implantation is an effective option for the treatment of complicated type B aortic dissection. Endovascular treatment achieved a better mid-term fate of the descending thoracic aorta than medical therapy alone, even in patients with worse preoperative conditions.  相似文献   
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OBJECTIVE   Genetic analysis is now essential for the accurate screening of families with multiple endocrine neoplasia type 2 (MEN2). We present the genetic analyses by both haplotype and direct RET proto-oncogene mutation analysis in seven Mediterranean MEN 2A families and have compared these results with biochemical screening tests and pathological examinations.
DESIGN  Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT   Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS   Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION   Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A.  相似文献   
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Peripheral blood lymphocytes from 17 patients with common variable hypogammaglobulinaemia (CVH) were tested for reactivity with the 5/9 monoclonal antibody which reacts with about 15% of normal T-PBL in which all helper activity is found. In PBL from CVH patients, the proportions of OKT4 and OKT8 positive cells were also determined. Five patients had normal percentages of 5/9 cells and a normal OKT4/OKT8 ratio. Twelve patients had significantly decreased (or absent) 5/9 lymphocytes. Among these, five had decreased 5/9 cells and a normal OKT4/OKT8 ratio and seven had decreased 5/9 cells and an inversion of the OKT4/OKT8 ratio. The deficiency of the helper phenotype T cell subpopulation identified by the 5/9 monoclonal antibody in many patients with CVH may be relevant in the pathogenesis of this disease.  相似文献   
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The Cellular Basis of Transplantation Tolerance in the Rat   总被引:3,自引:0,他引:3  
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