Publications by authors named "Knipper A"

Methods sections are often missing essential details. Methodological shortcut citations, in which authors cite previous papers instead of describing the method in detail, may contribute to this problem. This meta-research study used 3 approaches to examine shortcut citation use in neuroscience, biology, and psychiatry.

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This randomized prospective clinical study aims to analyze the differences between the computer-assisted planned implant position and the clinically realized implant position using dynamic navigation. In the randomized prospective clinical study, 30 patients were recruited, of whom 27 could receive an implant (BLT, Straumann Institut AG, Basel, Switzerland) using a dynamic computer-assisted approach. Patients with at least six teeth in their jaws to be implanted were included in the study.

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Campylobacteriosis outbreaks have repeatedly been associated with the consumption of raw milk. This study aimed to explore the variation in the prevalence and concentration of spp. in cows' milk and feces, the farm environment and on the teat skin over an entire year at a small German dairy farm.

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The consumption of raw milk from dairy cows has caused multiple food-borne outbreaks of campylobacteriosis in the European Union (EU) since 2011. Cross-contamination of raw milk through faeces is an important vehicle for transmission of Campylobacter to consumers. This systematic review and meta-analysis, aimed to summarize data on the prevalence and concentration of Campylobacter in faeces of dairy cows.

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Aim: One-piece ceramic implants (O-PCIs) have proven to be clinically useful, with high survival rates. The biocompatibility and bio-inert characteristics of ceramics in addition to the fact that minimal plaque deposits occur on these materials provide esthetic advantages and justification for their use in the anterior maxilla. The objective of the present study was to investigate the suitability of O-PCI use in the anterior maxilla.

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Background: This prospective clinical study aimed to investigate a possible deviation between the digitally planned implant position and the position achieved using dynamic navigation. The aim of the study was to establish clinical effectiveness and precision of implantation using dynamic navigation.

Methods: Twenty consecutive patients received an implant (iSy-Implantat, Camlog, Wimsheim, Germany).

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The aim of this in vitro study was to determine whether the process chain influences the accuracy of a computer-assisted dynamic navigation procedure. Four different data integration workflows using cone-beam computed tomography (CBCT), conventional impressions, and intraoral digitization with and without reference markers were analyzed. Digital implant planning was conducted using data from the CBCT scans and 3D data of the oral models.

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The aim of this systematic review and meta-analysis is to analyze the accuracy of implant placement using computer-assisted dynamic navigation procedures. An electronic literature search was carried out, supplemented by a manual search. The literature search was completed in June 2020.

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Background: Misclassification rates defined as upgrading, upstaging, and upgrading and/or upstaging have not been tested in contemporary Black patients relative to White patients who fulfilled criteria for very-low-risk, low-risk, or favorable intermediate-risk prostate cancer. This study aimed to address this void.

Methods: Within the SEER database (2010-2015), we focused on patients with very low, low, and favorable intermediate risk for prostate cancer who underwent radical prostatectomy and had available stage and grade information.

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Introduction: In this prespecified BRAVE 4 substudy we examined the antiplatelet and anticoagulant efficacy of clopidogrel plus heparin vs. prasugrel plus bivalirudin in patients with ST-segment elevation myocardial infarction.

Methods: 26 patients received clopidogrel/heparin, 25 patients received prasugrel/bivalirudin and 20 additional untreated patients served as controls.

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Introduction: To evaluate trends in efficacy and safety of flexible ureteroscopy (fURS) for the treatment of lower pole stones (LPS) over a 6-year period and to compare the annual outcomes after one fURS procedure retrospectively.

Patients And Methods: Four hundred nine patients were treated for pure LPS. An analysis of the annual outcomes regarding patient characteristics, operative parameters, stone-free rates (SFRs), and complication rates (CRs) was performed.

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Introduction: To evaluate the impact of surgical experience on ureteroscopic stone-free rates (SFR) and complication rates (CR) for the treatment of urinary calculi of the upper urinary tract.

Methods: We evaluated retrospectively, patients (n=300) having undergone ureteroscopy (URS) for single urinary calculi treated by residents (n=12) at our department over a 6-year period. These patients were matched according to age, gender, body-mass index, and stone side/size/site with patients (n=300) treated by consultants (n=5) of our department during the same period.

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Amniotic membrane transplantation has been used very successfully in ophthalmology since the 1940s for treatment of surface disorders. Over the course of the years the indications for use have been continuously extended. In contrast the operative technique is predominantly invasive, i.

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Purpose: Epidemic keratoconjunctivitis (EKC) is a severe ocular infection caused by a few types (8, 19a [relabeled as 64 recently], 37, 53, and 54) of human adenoviruses (HAdVs). HAdVs are known for their strong host species specificity that limits studying HAdV virulence and pathophysiology in animal models.

Methods: A HAdV infection model of primary porcine corneal epithelial cells (PPCE) and primary porcine corneal keratocytes (PPCK) was established and compared to primary human corneal epithelial cells (PHCE) and primary human corneal keratocytes (PHCK).

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In contrast to ureterosigmoidostomy no reliable clinical data exist for tumor risk in different forms of urinary diversion using isolated intestinal segments.In 44 German urological departments, operation frequencies, indications, patient age, and operation dates of the different forms of urinary diversion, operated between 1970 and 2007, could be registered. The secondary tumors up to 2009 were registered as well and related to the numbers of the different forms of urinary diversions resulting in tumor prevalences.

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Objectives: Cell-based tissue engineering concepts are becoming an important therapeutic alternative in the treatment of traumatic or chronic skeletal diseases. Here, we have evaluated cord blood-derived unrestricted somatic stem cells (USSCs) for use in bone and cartilage repair strategies.

Methods And Results: This type of somatic stem cell can be generated from cord blood with a current rate of 29% and we have documented excellent proliferation potential to high passage numbers.

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Unlabelled: Stem cell and tissue engineering-based therapies have become a promising option to heal bony defects in the future. Human cord blood-derived mesenchymal stem cells were seeded onto a collagen/tricalcium phosphate scaffold and xenotransplanted into critical size femoral defects of 46 nude rats. We found a survival of human cells within the scaffold and surrounding bone/bone marrow up to 4 wk after transplantation and an increased bone healing rate compared with controls without stem cells.

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Collagen-induced arthritis (CIA), an approved animal model for rheumatoid arthritis, is thought to be a T cell-dependent disease. There is evidence that CD8+ T cells are a major subset controlling the pathogenesis of CIA. They probably contribute to certain features of disease, namely tissue destruction and synovial hyperplasia.

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Background: Mesenchymal stem cells with an osteoblastic differentiating potency are investigated in regard of probable tissue engineering for further clinical application. The following report describes the use of cord blood derived stem cells as an alternative to other stem cell populations for bone regenerating tissue engineering.

Methods: To demonstrate the multipotency of cord blood derived mesenchymal stem cells, unrestringated somatic stem cells (USSC) were isolated from cord blood and underwent an osteo-, chondro- and adipoblastic in vitro stimulation.

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Over a period of more than four years of treatment, 177 Nevirapine plasma levels were taken from 27 patients. The values showed a high inter-patient variability and a lower intra-patient variability. Differences in body weight turned out to be the main reason for inter-patient variability.

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Here a new, intrinsically pluripotent, CD45-negative population from human cord blood, termed unrestricted somatic stem cells (USSCs) is described. This rare population grows adherently and can be expanded to 10(15) cells without losing pluripotency. In vitro USSCs showed homogeneous differentiation into osteoblasts, chondroblasts, adipocytes, and hematopoietic and neural cells including astrocytes and neurons that express neurofilament, sodium channel protein, and various neurotransmitter phenotypes.

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The present paper summarizes the results of the second German consensus meeting on immunogenetic donor search for allotransplantation of hematopoietic stem cells held in Essen in November 1999 under the auspices of the German Society for Immunogenetics (DGI) and the German Working Party for Blood and Marrow Transplantation (DAG-KBT). Immunogeneticists and transplant physicians from all over the country agreed to update the national standards for: (1) search strategy including the role of unrelated and extended family donor search after unsuccessful core family donor search, (2) histocompatibility loci to be typed, (3) histocompatibility typing techniques to be used (HLA serology vs DNA-based HLA typing, cellular tests, serum cross-match), and (4) acceptable HLA mismatches in the context of a defined underlying disease, donor type, and conditioning regimen.

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Allelic matching within the HLA-DRB1 and -DQB1 loci significantly improves the clinical outcome of hematopoietic stem cell transplantation. Consequently, allelic typing of these loci is strongly recommended for the unrelated stem cell donor selection. In this study, the HLA-DRB1,3,4,5 and -DQB1 alleles of 231 patients and their corresponding 821 nonrandom potential stem cell donors were determined to define compatible donor/recipient pairs.

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To date, human umbilical cord blood (CB) has been employed successfully in well over 1000 allogeneic (unrelated and sibling) stem cell transplantations. Because of primary limitations in volume and cell numbers, over 90% of these transplantations were performed in children. Therefore requests for well standardised cord blood units of high quality are now increasing constantly.

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