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991.
992.
We performed a randomised comparison of the i‐gel? and the Laryngeal Mask Airway (LMA) Classic? in children aged less than a year who were undergoing general anaesthesia for elective surgery. Fifty‐four infants were randomly allocated to either the i‐gel or the LMA Classic. We measured performance characteristics, fibreoptic views through the device and complications. Success rate at first insertion attempt was 100% (27/27) in the i‐gel group compared with 88% (23/26) in the LMA Classic group. Insertion of the device was considered easy in 26/27 (96%) patients in the i‐gel group compared with 18/26 (69%) patients in the LMA Classic group (p = 0.009). There were no differences between the groups in insertion times, fibreoptic views through the device, airway leak pressures or complications. We conclude that the i‐gel was considered easier to insert than the LMA Classic in infants.  相似文献   
993.
The influence of overweight and obesity on sperm quality and reproductive hormone levels is under discussion. The aim of the present retrospective study was to evaluate the influence of body mass index (BMI) on sperm quality and reproductive hormones. We analysed semen samples and serum levels of FSH, LH, T and PRL of a total of 2110 men attending our andrology unit from 1994 to 2010 due to infertility work‐up. Patients were stratified according to their BMI in four groups. Main outcome measures were sperm motility, morphology and concentration. Serum levels of FSH, LH, T and PRL were evaluated as well. No statistically significant difference was found for sperm quality and BMI between patients categorised according to the four BMI levels. T (P < 0.001) and LH (P = 0.006) significantly differed between the four groups. In multivariable analysis, BMI did not have significantly independent influence on all assessed sperm quality parameters, whereas BMI significantly influenced hormone values for LH (P = 0.001), T (P = <0.001) and PRL (P = 0.044). We therefore conclude that BMI has no significant impact on sperm quality parameters. However, serum levels of LH, T and PRL were significantly influenced by BMI.  相似文献   
994.
Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20–29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30–39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer‐assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (< 0.001) between CFTR expression and sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age.  相似文献   
995.
Sperm or testicular tissue cryopreservation is performed in cases of male infertility as a treatment for the preservation of fertility. When these sperm cells are used in assisted reproductive techniques, fertilisation rates, developmental and implantation potential of embryos decrease and the abortion rates increase. In the present work, differences of both phosphorylation and expression levels of p53 and Mitogen‐activated protein kinases (MAPK) proteins were analysed in 61 individual sperm samples before and after cryopreservation. We observed that p53 protein residue at Ser 15 was phosphorylated after cryopreservation. Because MAPK pathway activations may be involved in p53 phosphorylation, MAPK/ERK, Stress‐activated protein kinases (SAPK)/JNK and p38MAPK proteins were also investigated. Analysis showed that p38MAPK phosphorylations increased significantly. However, ERK and JNK expressions and phosphorylations decreased, although the differences were not statistically significant. According to our results, it may be suggested that cryopreservation process activates p53 via p38 MAPK pathway that subsequently causes apoptosis, which may be related to sperm parameters.  相似文献   
996.
As commonly used self‐reported screening instruments for male hypogonadism demonstrated lack of specificity, a Hypogonadism Related Symptom Scale (HRS) was developed in 2009 as a novel self‐rating screening tool. As the questionnaire has not been validated, the purpose of our study was to perform a validation in patients presenting with different disorders (e.g. infertility, HIV infection or metabolic syndrome) and disease‐related risk to develop hypogonadism. Two hundred and eighteen patients aged 19–71 years (40.1 ± 9.5) who completed the HRS and other common questionnaires [International Index Of Erectile Function (IIEF), National Institutes of Health Chronic Prostatitis Symptom Index (NIH‐CPSI), Hospital Anxiety and Depression Scale (HADS), short form (SF)‐12] were included. In all patients, blood levels of total testosterone, luteinizing hormone, follicle‐stimulating hormone, oestradiol and sex hormone‐binding globulin were determined and free testosterone was calculated. Cronbach's α for the scale was 0.896, split‐half 0.871 for the 1st half and 0.807 for the 2nd half. Spearman–Brown coefficient was 0.767, and Guttman split‐half coefficient was 0.759. Consistent correlations were found between HRS and IIEF5 (ρ = 0.57, P < 0.001), and HADS (ρ = ?0.6, P < 0.001). In addition, HRS was significantly correlated with total testosterone (ρ = 0.135, P < 0.05), free testosterone (ρ = 0.148, P < 0.05) and oestradiol (ρ = ?0.134, P < 0.05). Our validation study confirms the data from the initial development of the HRS questionnaire. Clinicians might have an additional advantage from the HRS when investigating males with suspected hypogonadism.  相似文献   
997.
998.
There is no report on the effects of sustained low‐efficiency dialysis (SLED) plus hemoperfusion (HP) (SLED + HP) in patients with acute severe organophosphate (OP) poisoning (ASOPP). This study was designed to compare the therapeutic effectiveness between SLED + HP and continuous hemofiltration (CHF) plus HP (CHF + HP) in patients with ASOPP. In order to assess the two treatment methods, 56 patients with ASOPP were divided into CHF + HP group and SLED + HP group. The biochemical indicators, in‐hospital duration, hemodynamic parameters, Acute Physiology, and Chronic Health Evaluation (APACHE II) score, and survival and mortality rates were compared. In both groups after treatment, the levels of serum creatine kinase isozyme MB, creatine kinase, creatinine, glutamic‐oxalacetic transaminease, and glutamate‐pyruvate transaminase, and the APACHE II scores on the first, second, and seventh day decreased (P < 0.05), whereas the levels of serum acetylcholinesterase increased. The two groups showed no statistical differences in in‐hospital duration, biochemical indicators, APACHE II score, hemodynamic parameters, survival rate, or the mortality rate (P > 0.05). In conclusion, SLED has similar hemodynamic stability to CHF and the two treatment methods have similar effects on ASOPP patients. More importantly, SLED plus HP is relatively economical and convenient for patients with ASOPP in clinical practice.  相似文献   
999.
To date, ventricular assist devices (VADs) have become accepted as a therapeutic solution for end‐stage heart failure patients when a donor heart is not available. Newer generation VADs allow for a significant reduction in size and an improvement in reliability. However, the invasive implantation still limits this technology to critically ill patients. Recently, expandable/deployable devices have been investigated as a potential solution for minimally invasive insertion. Such a device can be inserted percutaneously via peripheral vessels in a collapsed form and operated in an expanded form at the desired location. A common structure of such foldable pumps comprises a memory alloy skeleton covered by flexible polyurethane material. The material properties allow elastic deformation to achieve the folded position and withstand the hydrodynamic forces during operation; however, determining the optimal geometry for such a structure is a complex challenge. The numerical finite element method (FEM) is widely used and provides accurate structural analysis, but computation time is considerably high during the initial design stage where various geometries need to be examined. This article details a simplified two‐dimensional analytical method to estimate the mechanical stress and deformation of memory alloy skeletons. The method was applied in design examples including two popular types of blade skeletons of a foldable VAD. Furthermore, three force distributions were simulated to evaluate the strength of the structures under different loading conditions experienced during pump operation. The results were verified with FEM simulations. The proposed two‐dimensional method gives a close stress and deformation estimation compared with three‐dimensional FEM simulations. The results confirm the feasibility of such a simplified analytical approach to reveal priorities for structural optimization before time‐consuming FEM simulations, providing an effective tool in the initial structural design stage of foldable minimally invasive VADs.  相似文献   
1000.
In order to improve the treatment of children born with long‐gap esophageal atresia, a porcine model was developed for studying esophageal regrowth using a bridging graft composed of a silicone stented Biodesign mesh. The aim of the study was to investigate how leakage and contact between the native muscle and Biodesign mesh affected the early healing response. Resection of 3 cm of intrathoracic esophagus was performed in 10 newly weaned piglets. They were fed through a gastrostomy 8–10 days prior to sacrifice. In order to achieve nonleaking anastomoses, the silicone stent and suturing technique had to be adjusted between the first four and second six piglets. The technical adjustment decreased leakage. A nonleaking anastomosis could not be achieved when the native muscle layers were sewn less central on the bridging graft compared with the mucosa. If there was leakage, the inflammatory response increased, with islets of perivascular T‐lymphocytes and infiltration of macrophages in the native muscle layers. In the bridging area, new vessels were seen in the submucosa in 9 of 10 piglets between 4 and 10 days after surgery. Smooth muscle cells also appeared to move from the cut muscle edges of both the muscularis mucosa and the lamina muscularis and were seen as a layer of several cells under newly formed mucosa. Double staining of the basal membrane of the ingrowing vessels and the pericytes showed that the basal membrane was thinner over some of the pericytes, but there was no accumulation of immature‐looking cells in the submucosa of the bridging area. In this porcine model, where esophageal regrowth was studied by using a bridging graft composed of a silicone stented Biodesign mesh, we can conclude that leakage increased the inflammatory response in early healing. Ingrowth of new vessels was seen in the bridging area and movement of smooth muscle cells was found under newly formed mucosa.  相似文献   
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