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81.
Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11 总被引:56,自引:0,他引:56
Vogt PH; Edelmann A; Kirsch S; Henegariu O; Hirschmann P; Kiesewetter F; Kohn FM; Schill WB; Farah S; Ramos C; Hartmann M; Hartschuh W; Meschede D; Behre HM; Castel A; Nieschlag E; Weidner W; Grone HJ; Jung A; Engel W; Haidl G 《Human molecular genetics》1996,5(7):933-943
In a large collaborative screening project, 370 men with idiopathic
azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA
loci in Yq11. In 12 individuals, we observed de novo microdeletions
involving several DNA loci, while an additional patient had an inherited
deletion. They were mapped to three different subregions in Yq11. One
subregion coincides to the AZF region defined recently in distal Yq11. The
second and third subregion were mapped proximal to it, in proximal and
middle Yq11, respectively. The different deletions observed were not
overlapping but the extension of the deleted Y DNA in each subregion was
similar in each patient analysed. In testis tissue sections, disruption of
spermatogenesis was shown to be at the same phase when the microdeletion
occurred in the same Yq11 subregion but at a different phase when the
microdeletion occurred in a different Yq11 subregion. Therefore, we propose
the presence of not one but three spermatogenesis loci in Yq11 and that
each locus is active during a different phase of male germ cell
development. As the most severe phenotype after deletion of each locus is
azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable
phase of function in human spermatogenesis and candidate genes involved
will be discussed.
相似文献
82.
Barge-Schaapveld DQ Maas SM Polstra A Knegt LC Hennekam RC 《American journal of medical genetics. Part A》2011,155(5):1066-1072
One of the recently recognized microdeletion syndromes is the 16p11.2 deletion syndrome (593 kb; ~29.5 Mb to ~30.1 Mb), associated with developmental delay, autism spectrum disorder, epilepsy, and obesity. Less frequently reported is a smaller 220 kb deletion, adjacent and distal to this 16p11.2 deletion, which has been referred to as the atypical 16p11.2 deletion (220 kb; ~28.74 Mb to ~28.95 Mb). We describe three patients with this deletion and update the manifestations in two sibs who have been described as possibly new entity in this Journal in 1997 [Bakker and Hennekam (1997); Am J Med Genet 70:312–314] and were recently found to have the “atypical 16p11.2 deletion” as well. Patients show a developmental delay, behavioral problems, and unusual facial morphology (prominent forehead, downslanted, and narrow palpebral fissures), and some are obese. We suggest that this “atypical” deletion may turn out to become a microdeletion syndrome that will be recognizable in the future, or at least to show a phenotype that is recognizable in retrospect. As it may no longer be so “atypical,” we suggest renaming the entity “distal 16p11.2 deletion,” to distinguish it from the common proximal 16p11.2 deletion. © 2011 Wiley‐Liss, Inc. 相似文献
83.
M.A.C. Broeren Y. Maas E. Retera N.L.A. Arents 《Clinical microbiology and infection》2013,19(3):286-291
The rise in antimicrobial resistance has become a serious global health problem. Restrictive use of antibiotics seems the only option to temper this accession since research in new antibiotics has halted. Antimicrobial stewardship programmes rely on quick access to susceptibility data. This study evaluated the concept of bacterial cell count monitoring as a fast method to determine susceptibility. Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus strains were tested for amoxicillin/piperacillin and gentamicin by three conventional methods (VITEK2®, Etest® and broth-macrodilution). Bacterial cell count monitoring reliably predicted susceptibility after 90 min for Escherichia coli and after 120 min for Pseudomonas aeruginosa and Staphylococcus aureus without any minor, major or very major discrepancies. Time-to-result was reduced by 74%, 83% and 76%, respectively. Bacterial cell count monitoring shows great potential for rapid susceptibility testing. 相似文献
84.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献85.
S. van Drongelen J. C. Maas A. Scheel-Sailer L. H. V. Van Der Woude 《Journal of medical engineering & technology》2013,37(2):151-157
Purpose: To evaluate the effect of the spatial orientation of the crank axis on mechanical efficiency, physiological strain and perceived discomfort in submaximal synchronous arm crank ergometry.Methods: Twelve able-bodied individuals performed 12 submaximal exercise bouts of 3 minutes (women: 20 W/25 W; men: 25 W/35 W). The crank axis position was defined by elbow and shoulder angle.Results: The results showed that a crank set-up with an elbow angle of 30° was more efficient than 15°; oxygen consumption and minute ventilation were significantly lower. No significant effects were seen for shoulder angle. Power output and gender showed obvious effects.Discussion and conclusion: The magnitude of this effect and the absence of any significant shoulder angle effects may be due to the relative low exertion levels that were evaluated. An elbow angle of 30° flexion in arm crank exercise is favourable compared to an elbow angle of 15° in able-bodied untrained subjects. 相似文献
86.
Matthew B. Maas Neil F. Rosenberg Adam R. Kosteva Shyam Prabhakaran Andrew M. Naidech 《Neurocritical care》2013,18(2):166-169
Background
Anticoagulation increases the risk of intracerebral hemorrhage (ICH), yet whether different underlying disease processes are equally affected is unknown. We tested the hypothesis that coagulopathy, measured by admission international normalized ratio (INR), disproportionately increases the risk for lobar hemorrhages.Methods
Patients with primary ICH were enrolled into a registry between December 2006 and February 2012 with prospective data acquisition and systematic follow up. Logistic regression was used to test whether lobar versus deep ICH location was independently associated with INR, and then whether INR had an influence on mortality. Spearman’s correlation coefficient was used to test for an association between INR and hematoma volume separately in the lobar and deep ICH groups.Results
221 patients were studied. Patients with lobar ICH were older (71 vs. 62 years old, p < 0.001) and more likely to have prior ICH (10 vs. 0 %, p < 0.001). INR >1.4 was observed on admission more frequently in lobar versus deep ICH (19 vs. 8 %, p = 0.02). Lobar ICH location was independently associated with INR >1.4 (OR: 2.51, 95 % CI: 1.03–6.14, p = 0.043). ICH volume correlated with INR in lobar ICH (p = 0.009), but not deep ICH (p = 0.8). Death at 1 month was independently associated with INR >1.4 (OR: 7.6, 95 % CI: 2.4–24.1, p = 0.001) after correction for the ICH Score.Conclusions
Abnormal coagulation occurs disproportionally in lobar versus deep ICH, and is associated with larger ICH volumes and higher mortality. These findings suggest a unique risk interaction between coagulopathy and underlying brain pathology due to cerebral amyloid angiopathy. 相似文献87.
88.
LJ Gould J Mushkudiani H Hou OY Grinberg S Grinberg HM Swartz 《Wound repair and regeneration》2004,12(2):A29-A29
Methods to reliably measure tissue oxygenation in situ are currently lacking. We have developed a vertically oriented, dorsal, bipedicle flap model that is easy to perform, reliably reproduces tissue ischemia, eliminates craniocaudal variation, and is amenable to studying therapeutic modalities. The effect of narrowing this flap on tissue oxygenation measured with Licox electrodes has previously been presented. In this study we utilize in situ EPR spectroscopy to demonstrate the oxygen gradient in the flap as a function of flap width and placement of a silicone sheet directly under the flap. The effect of wound healing over a 2 week period is demonstrated. Twenty four, 300 gm male Sprague‐Dawley rats underwent creation of the bipedicle flap according to the following groups: 2.5 cm flap with silicone, 2.0 cm flap without silicone, 2.0 cm flap with silicone. Each group of 6 animals was injected with EMS char at 2 cm intervals along the flap and one injection in the control, non‐ischemic tissue. A 4th group underwent 2.0 cm flaps with silicone and use of lithium phthalocyanin as the paramagnetic material. Wound measurements and EPR spectroscopy were performed on days 3, 7, 10 and 14. On day 14, after EPR measurements, the animals were sacrificed and their wounds excised. One flap and one control wound were preserved for histologic analysis, the other flap and control wounds were prepared for lactate measurements. EPR spectroscopy demonstrated a gradient of oxygen that was lowest in the center of the flap and greatest at either end. Changes in the oxygen gradient correlated with narrowing and placement of the intervening silicone sheet. This new technology has never been utilized in an animal model of impaired wound healing. Comparison of recently developed paramagnetic materials for optimal tissue oxygen and free radical measurements will be presented. 相似文献
89.
Over the last several years, Botox has become an integral treatment modality in the management of facial aging. Through selective chemical denervation, rhytids that are associated with hyperfunctioning muscles can be considerably softened or eliminated. Most practitioners rely on surface anatomy and landmarks to guide accurate needle insertion and Botox therapy. Therefore, a detailed appreciation of the underlying muscular anatomy is paramount in improving the practitioner's cosmetic results and the patients' overall satisfaction. 相似文献
90.
Videolaryngoscopy vs. direct laryngoscopy use by experienced anaesthetists in patients with known difficult airways: a systematic review and meta‐analysis 下载免费PDF全文
B. M. A. Pieters E. H. A. Maas J. T. A. Knape A. A. J. van Zundert 《Anaesthesia》2017,72(12):1532-1541
Experienced anaesthetists can be confronted with difficult or failed tracheal intubations. We performed a systematic review and meta‐analysis to ascertain if the literature indicated if videolaryngoscopy conferred an advantage when used by experienced anaesthetists managing patients with a known difficult airway. We searched PubMed, MEDLINE, Embase and the Cochrane central register of controlled trials up to 1 January 2017. Outcome parameters extracted from studies were: first‐attempt success of tracheal intubation; time to successful intubation; number of intubation attempts; Cormack and Lehane grade; use of airway adjuncts (e.g. stylet, gum elastic bougie); and complications (e.g. mucosal and dental trauma). Nine studies, including 1329 patients, fulfilled the inclusion criteria. First‐attempt success was greater for all videolaryngoscopes (OR 0.34 (95%CI 0.18–0.66); p = 0.001). Use of videolaryngoscopy was associated with a significantly better view of the glottis (Cormack and Lehane grades 1 and 2 vs. 3–4, OR 0.04 (95%CI 0.01–0.15); p < 0.00001). Mucosal trauma occurred less with the use of videolaryngoscopy (OR 0.16 (95%CI 0.04–0.75); p = 0.02). Videolaryngoscopy has added value for the experienced anaesthetist, improving first‐time success, the view of the glottis and reducing mucosal trauma. 相似文献