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101.
BACKGROUND: Sutureless re-anastomosis per laparoscopy is an alternative for microsurgical re-anastomosis by laparotomy in the treatment of sterilized women with renewed child wish. Our aim was to compare pregnancy rates after both surgical techniques. METHODS: We performed a retrospective cohort study in which consecutive women who underwent sutureless re-anastomosis per laparoscopy were compared to women who underwent microsurgical re-anastomosis by laparotomy. Both procedures were performed in neighbouring hospitals in Northern-Brabant, The Netherlands, and women were matched for age. The primary outcome was time to ongoing pregnancy. RESULTS: Overall, we included 41 women who had sutureless re-anastomosis by laparoscopy, and 41 age-matched women who underwent microsurgical re-anastomosis by laparotomy. The number of women who conceived was 20 (15 ongoing pregnancies) in the sutureless laparoscopic group versus 26 (24 ongoing pregnancies) in the laparotomic group, a difference due to a longer follow-up period in the laparotomic group. Time to ongoing pregnancy was comparable in both groups (P=0.46), with 3 year cumulative ongoing pregnancy rates of 45 and 52% respectively. After adjustment for other prognostic factors, the fecundity rate ratio was 0.97 (95% CI 0.26-3.6), indicating a similar performance of the two techniques. CONCLUSION: The simplified stitchless laparoscopic procedure for reversal of tubal sterilization with the use of a tubal splint, clip fixation of the muscularis and fibrin glue resulted in a promising pregnancy rate, which was similar to the pregnancy rate obtained with the microsurgical re-anastomosis per laparotomy.  相似文献   
102.
DRAK2 is a member of the death-associated protein (DAP)-like family of serine/threonine kinases. Members of this family induce apoptosis in various cell types. DRAK2, in particular, is specifically expressed in T cells and B cells, and it is differentially regulated during T cell development. To determine whether DRAK2 regulates lymphocyte apoptosis, we produced Drak2(-/-) mice. Contrary to our expectations, Drak2(-/-) T cells did not demonstrate any defects in apoptosis or negative selection; however, T cells from Drak2(-/-) mice exhibited enhanced sensitivity to T cell receptor-mediated stimulation with a reduced requirement for costimulation. These results provide evidence that DRAK2 raises the threshold for T cell activation by negatively regulating signals through the TCR. In contrast to other models of T cell hypersensitivity, Drak2(-/-) mice were remarkably resistant to experimental autoimmune encephalomyelitis (EAE). These results expose a new pathway regulating T cell activation and highlight the intricacies of induced autoimmune disease.  相似文献   
103.
Human eosinophils produce a large number of cytokines, including immunoregulatory cytokines. Given that eosinophils store and release interleukin (IL)-4, a key cytokine in the pathogenesis of allergic inflammation, and that IL-4 and IL-13 share common biological functions, we investigated the possibility that IL-13 may be synthesized by these cells. Using flow cytometry and immunocytochemistry, we show that eosinophils synthesize and store IL-13. Granule localization was demonstrated after subcellular fractionation, and IL-13 immunoreactivity was localized to crystalloid, granule-enriched fractions. Furthermore, electron microscopic analyses specifically localized IL-13 to the dense cores of bicompartmental secondary granules. Upon CD28 ligation, IL-13 was released by eosinophils, whereas a combination of CD28 and immunoglobulin A complexes resulted in decreased IL-13 secretion. Furthermore, eosinophil-derived IL-13 exerts a biological effect, inducing CD23 expression on B cells. By having the capacity to synthesize and release IL-13, eosinophils may participate in the development and maintenance of the T helper cell type 2 response, a prominent feature of allergic diseases.  相似文献   
104.
Maternal uniparental disomy for the entire chromosome 7 hasso far been reported in three patients with intrauterine andpostnatal growth retardation. Two were detected because theywere homozygous for a cystic fibrosis mutation for which onlythe mother was heterozygous, and one because he was homozygousfor a rare COL1A2 mutation. We investigated 35 patients witheither the Silver-Russell syndrome or primordial growth retardationand their parents with PCR markers to search for uniparentaldisomy 7. Four of 35 patients were found to have maternal disomy,including three with isodisomy and one with heterodisomy. Thedata confirm the hypothetical localization of a maternally imprintedgene (or more than one such gene) on chromosome 7. It is suggestedto search for UPD 7 in families with an offspring with sporadicSilver-Russell syndrome or primordial growth retardation.  相似文献   
105.
Summary Reticulocyte count comparisons were made on ten trained and ten sedentary college males before and immediately after heavy exercise and following 15 min of recovery. No significant differences occurred within or between groups; in fact, all means were within the normal range. Previous findings were discussed. It was concluded that a physiologically significant increase in reticulocytes does not occur as a result of exercise or training and therefore can not be a mechanism for increased maximal oxygen uptake.  相似文献   
106.
A frame-shift 9254del5 mutation was independently identified in 12 families, eleven of them with Spanish ancestors, in a BRCA2 screening performed in 841 breast and/or ovarian cancer families and in 339 women with breast cancer diagnosed before the age of 40 at different centers in France and Spain. We sought to analyze in detail the haplotype and founder effects of the 9254del5 and to estimate the time of origin of the mutation. Eight polymorphic microsatellite markers and two BRCA2 polymorphisms were used for the haplotype analyses. The markers were located flanking the BRCA2 gene spanning a region of 6.1 cM. Our results suggest that these families shared a common ancestry with BRCA2 9254del5, which is a founder mutation originating in the Northeast Spanish, with an estimated age of 92 (95% CI 56-141) generations.  相似文献   
107.
BACKGROUND AND PURPOSE: The optimal intensity fluence profile of a beam depends on the profiles of other beams but most optimizations assume fixed beam orientations, a priori. Breast cancer radiotherapy attempts to cover the target and to spare critical structures such as the heart and lungs. The study aims are (1) to determine and document the optimal two-beam orientation that best spares the heart for left-sided breast cancer patients and (2) to investigate the influence of the treatment technique (i.e., conformal versus intensity modulation) on the optimal objective cost function. MATERIAL AND METHODS: Ten left-sided breast cancer patients were planned using a conformal (3DCRT) and a simplified intensity modulated (sIMRT) technique using predefined segments and different two-beam orientations. Optimal segment weights were determined exhaustively for all axial two-beam combinations, in 5 degree increments, by minimizing a quadratic objective cost function. The resulting objective cost function was analyzed with respect to target geometry and treatment technique. RESULTS: The sIMRT plans are generally less sensitive to beam orientation compared to 3DCRT plans. Optimal two-beam orientations for 3DCRT and sIMRT plans exist and they correspond to a hinge angle of approximately 188 degrees and 160 degrees or 210 degrees (the latter is bimodal), respectively. CONCLUSIONS: The optimization software is a useful tool that can test many different beam combinations and estimate their associated objective cost values. Afterwards, the most promising beam orientations could be re-optimized under the TPS to fine-tune and verify the dose distributions. Optimal uniform two-beam orientations for the breast consist of opposing tangential medial and lateral beams. Optimal nonuniform two-beam orientations for left-sided breast cancers are bimodal, containing hinge angles around 160 degrees and 210 degrees. Nonuniform beam techniques are less sensitive to beam orientation compared to uniform beam techniques and result in significantly improved heart sparing but at a cost of slightly compromised planning target volume coverage.  相似文献   
108.
We report an inbred Tunisian family, in which the proband manifested signs of hypohidrotic ectodermal dysplasia, subtotal amelia, scoliosis and left renal agenesis. Two other family members had the full clinical criteria of hypohidrotic ectodermal dysplasia, characterized by deficient sweat glands, hypodontia, hypoplasia of the mucous glands, and fine hair. Nine family subjects had variable clinical expression of the disorder.  相似文献   
109.
Properties of a Hemolysin Produced by Group B Streptococci   总被引:7,自引:6,他引:7       下载免费PDF全文
A hemolysin that appears to be responsible for the zones of beta-hemolysis surrounding colonies of group B streptococci (Streptococcus agalactiae) on blood agar plates has been isolated and partially purified. No soluble hemolysin was detectable in the supernatants of streptococcal cultures grown in several types of media. However, hemolytic activity was detected when streptococci were incubated with erythrocytes, and soluble hemolysin was isolated when bacterial suspensions were incubated in the presence of a variety of agents, including calf serum, albumin, Tween 80, and starch. Glucose and other fermentable carbohydrates stimulated hemolysin production, and metabolic inhibitors greatly reduced the titer of hemolysin that could be recovered, suggesting that cellular metabolism is necessary for hemolysin production or release. The soluble hemolysin was concentrated by ammonium sulfate precipitation and partially purified by gel filtration. Agents known to inhibit other streptococcal hemolysins, including phospholipids, trypan blue, proteases, and cholesterol, were tested for their effect on the group B hemolysin. Only the phospholipids inhibited hemolysin activity. The group B streptococcal hemolysin appears to be similar to, but distinct from, streptolysin S produced by Streptococcus pyogenes.  相似文献   
110.
We report an African infant with Ellis‐van Creveld (EVC) syndrome. EVC syndrome is a chondral and ectodermal dysplasia with autosomal recessive transmission. The baby presented with polydactyly, short limbs and atrioventricular septal defect, but was withdrawn from clinical follow up for the first year of life. Initial hematological abnormalities could not be explained and normalized later. EVC syndrome was confirmed by genetic analysis that showed two pathogenic mutations in the EVC2 gene, c.653_654del, p.Val218Glyfs*12 in exon 5, and c.2710C>T, p.Gln904* in exon 16. The variant c.653_654del; p.Val218Glyfs*12 in exon 5 has not been described before. Our review of medical literature suggested this is the first molecularly confirmed case of EVC syndrome in sub‐Saharan Africa.  相似文献   
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