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991.
Natalibeth Barrera Rosina Ordoqui José M. Montes Mariel Canepa Carla Bonelli Carolina Surka Andrea Torrens Lidia Cantú Stefan S. Du Plessis 《Andrologia》2020,52(2):e13502
Several studies have reported a global decline in seminal quality over the years. The objective of this study was to describe the semen donor population of Uruguay through comparing data of successive samples banked by the same donors and the analysis of their semen and physical characteristics, ancestry origin and educational level. A total of 3,449 ejaculated samples collected from 71 donors, cryobanked between 1989 and March 2017 at Fertilab, were analysed. Results revealed a mean age of 23.90 ± 3.98 years, an average weight of 74.95 ± 1.09 kg and a mean height of 1.78 ± 0.06 m. The majority of the donors trace their origin to Europe (74.65%, 53/71) and 66.19% (47/71) have a level of education higher than secondary school. We observed longitudinal differences in two parameters, that is sperm concentration and semen volume. Sperm concentration declined, while semen volume increased significantly over the 28-year period. The results of the present study are in accordance with that of previous articles that also reported a decline in sperm concentration over time. However, no differences were observed in total sperm number per ejaculate due to the increase in semen volume values, thus reflecting no real changes in sperm production over time. 相似文献
992.
993.
Matthias Mehdorn Stefan Niebisch Uwe Scheuermann Ines Gockel 《Acta chirurgica Belgica》2020,120(4):250-256
AbstractPurpose: There is evidence from various surgical specialties that incisional negative pressure wound therapy (iNPWT) might reduce postoperative surgical site infections (SSIs). In visceral and general surgery, there is varying evidence of its efficacy in reducing surgical site infections.Methods: A prospectively registered patient cohort of 43 patients with abdominal wall and visceral surgery received treatment with iNPWT and was compared to a matched retrospective cohort to analyze its effects on SSI occurrence and respective risk factors. Groups were matched by procedure, sex, body mass index and age. We used two different systems of iNPWT: (i) PREVENATM or (ii) self-made epicutaneous iNPWT from common VAC material.Results: We could not find a total reduction in postoperative SSIs by application of iNPWT. But within the iNPWT cohort, patients with self-made iNPWT suffered more often from SSIs compared to the commercial iNPWT subgroup. No patient specific risk factors could be identified to advocate the use of iNPWT.Conclusion: Our data do not support the use of an incisional negative pressure wound therapy on closed wounds in midline laparotomy incisions. Although, differences exist between the commmercial and self-made systems. 相似文献
994.
Huub Schellekens Sven Stegemann Vera Weinstein Jon S. B. de Vlieger Beat Flühmann Stefan Mühlebach Rogério Gaspar Vinod P. Shah Daan J. A. Crommelin 《The AAPS journal》2014,16(1):15-21
The aim of this critical review is to reach a global consensus regarding the introduction of follow-on versions of nonbiological complex drugs (NBCD). A nonbiological complex drug is a medicinal product, not being a biological medicine, where the active substance is not a homo-molecular structure, but consists of different (closely related and often nanoparticulate) structures that cannot be isolated and fully quantitated, characterized and/or described by state of the art physicochemical analytical means and where the clinical meaning of the differences is not known. The composition, quality and in vivo performance of NBCD are highly dependent on manufacturing processes of both the active ingredient as well as in most cases the formulation. The challenges posed by the development of follow-on versions of NBCD are illustrated in this paper by discussing the ‘families’ of liposomes, iron–carbohydrate (‘iron–sugar’) drugs and glatiramoids. It is proposed that the same principles for the marketing authorization of copies of NBCD as for biosimilars be used: the need for animal and/or clinical data and the need to show similarity in quality, safety and efficacy. The regulatory approach of NBCD will have to take into consideration the specific characteristics of the drugs, their formulation and manufacturing process and the resulting critical attributes to achieve their desired quality, safety and efficacy. As with the biosimilars, for the NBCD product, family-specific methods should be evaluated and applied where scientifically proven, including sophisticated quality methods, pharmacodynamic markers and animal models. Concerning substitution and interchangeability of NBCD, it is also advisable to take biosimilars as an example, i.e. (1) substitution without the involvement of a healthcare professional should be discouraged to ensure traceability of the treatment of individual patients, (2) keep an individual patient on a specific treatment if the patient is doing well and only switch if unavoidable and (3) monitor the safety and efficacy of the new product if switching occurs. 相似文献
995.
Stefan Bittner Tobias Ruck Juncal Fernández-Orth Sven G. Meuth 《Journal of neuroimmune pharmacology》2014,9(3):293-301
TWIK-related potassium channel-1 (TREK1, KCNK2) is the most extensively studied member of the two-pore domain potassium (K2P) channel family. Recent studies have already demonstrated a key role in the pathophysiology of depression, pain and neurodegenerative damage pointing towards an important role in a broad spectrum of CNS disorders. The mammalian blood–brain barrier (BBB) is a highly specialized structure and an integral part of the neurovascular unit, which controls the transition of cells and molecules into the CNS. While BBB dysregulation is common in neurologic diseases, the molecular mechanisms involved in this process remain largely unknown. Recently, we were able to describe a role of TREK1 in this context. TREK1 was downregulated in murine and human BBB upon inflammation. Blocking of TREK1 increased lymphocyte migration, while activation had the opposite effect. In TREK1-deficient (Trek1 ?/? ) mice, brain endothelial cells displayed an inflammatory phenotype and leukocyte trafficking was facilitated, as demonstrated in experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis. Here we summarize these findings and discuss the implications in diseases related to BBB dysfunction. 相似文献
996.
Matthias Braito Dietmar Dammerer Gerhard Kaufmann Stefan Fischler James Carollo Andrea Reinthaler Dennis Huber Rainer Biedermann 《International orthopaedics》2014,38(8):1647-1653
Purpose
Prior studies have reported improved gait performance and kinematics after total ankle arthroplasty (TAR) compared to ankle arthrodesis (AAD). Given these findings, AAD has been primarily considered as a salvage procedure that may lead to adjacent joint degeneration.Methods
A total of 101 TAR and 40 screw arthrodeses were enrolled in a retrospective study with a prospectively designed follow-up examination that included gait analysis and outcome assessment with the AOFAS hindfoot score and FAOS questionnaire.Results
Significant asymmetry in gait and reduced range of motion compared to normal remained after both procedures. Subjective outcome improved after both procedures, and pain was significantly better after TAR. Limited functional gains after TAR and joint degeneration to the same degree after both procedures was seen in the mid-term. Hindfoot fusion seemed to have a greater impact on postoperative function than ankle arthrodesis.Conclusion
Considering only minor functional gains of TAR compared to AAD the implantation of current TAR designs in large patient series may be questioned. 相似文献997.
998.
999.
Tim Wehner Katharina Gruchenberg Ronny Bindl Stefan Recknagel Malte Steiner Anita Ignatius Lutz Claes 《Journal of orthopaedic research》2014,32(12):1589-1595
The healing process consists of at least three phases: inflammatory, repair, and remodeling phase. Because callus stiffness correlates with the healing phases, it is suitable for evaluating the fracture healing process. Our aim was to develop a method which allows determination of callus stiffness in vivo, the healing time and the duration of the repair phase. The right femurs of 16 Wistar rats were osteotomized and stabilized with either more rigid or more flexible external fixation. Fixator deformation was measured using strain gauges during gait analysis. The strains were recalculated as the callus stiffness over the time course of healing, and the healing phases were identified based on stiffness thresholds. Our hypothesis was that stabilization with more flexible external fixation prolongs the repair phase, therefore resulting in an extended healing time. Confirming our hypothesis, the duration of the repair phase (rigid: approximately 15 days, flexible: approximately 41 days) and the healing time (rigid: approximately 27 days, flexible: approximately 62 days) were significantly longer for more flexible external fixation. Our method allows the quantitative detection of differences in the healing time and duration of the repair phase without multiple time‐point sacrifices, which reduces the number of animals in experimental studies. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1589–1595, 2014. 相似文献
1000.
Angelo M. Dell'Aquila Stefan R.B. Schneider Jörg Stypmann Björn Ellger Bassam Redwan Dominik Schlarb Sven Martens Jürgen R. Sindermann 《Artificial organs》2014,38(5):383-390
Reports on third‐generation centrifugal intrapericardial pumps (HeartWare International, Inc., Framingham, MA, USA) have shown better survival results than the previous‐generation devices. However, outcomes depending on the preoperative level of stability can substantially differ, resulting in a limited analysis of potentialities and drawbacks of a given device. In the present study we sought to compare in our single‐center experience the survival results of this third‐generation device with previous left ventricular systems taking into account the different preoperative Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels. Between February 1993 and March 2012, 287 patients underwent assist device implantation in our university hospital (INTERMACS Level 1‐2 = 158 patients; INTERMACS Level 3‐4‐5 = 129 patients). Assist devices implanted were: Group A (HVAD HeartWare, n = 52), group B (previous continuous‐flow ventricular assist device [VAD], InCor [Berlin Heart, Berlin, Germany], n = 37; VentrAssist [VentraCor, Inc., Chatswood, NSW, Australia], n = 7; DeBakey [MicroMed Cardiovascular, Inc., Houston, TX, USA], n = 32), and group C (pulsatile systems, n = 159). After cumulative support duration of 54 436 days and a mean follow‐up of 6.21 ± 7.46 months (range 0–45.21 months), log‐rank analysis revealed a survival for group A of 82.0%, 70.4%, and 70.4%; for group B of 84.0%, 48.2%, 33.7%; and for group C of 71.6%, 46.1%, 33.8%, at 1, 12, and 24 months respectively, with a significantly (P = 0.013) better outcome for group A. When stratifying the survival on the basis of INTERMACS level, no significant survival improvement was observed among all patients who underwent VAD implantation in INTERMACS 1‐2 (P = 0.47). However, among patients who underwent elective VAD implantation (INTERMACS 3‐4‐5), group A had a significantly better outcome (P = 0.005) compared with the other INTERMACS‐matched groups (B,C) with a survival rate of 88.8% in group A versus 34.2% in group B and 45.6% in group C at 24 months, respectively. Elective HVAD system implantation shows improved survival benefit over the other INTERMACS‐matched devices. Moreover, preoperative unstable hemodynamics resulted in a poor prognosis independently from the pump generation. 相似文献