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991.
Extremely sensitive, background-free gene detection using binary probes and beta replicase. 总被引:2,自引:0,他引:2 下载免费PDF全文
S Tyagi U Landegren M Tazi P M Lizardi F R Kramer 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(11):5395-5400
We have developed a specific and sensitive nucleic acid amplification assay that is suitable for routine gene detection. The assay is based on a novel molecular genetic strategy in which two different RNA probes are hybridized to adjacent positions on a target nucleic acid and then ligated to form an amplifiable reporter RNA. The reporter RNA is then replicated up to a hundred billion-fold in a 30-min isothermal reaction that signals the presence of the target. The assay can detect fewer than 100 nucleic acid molecules; it provides quantitative results over a wide range of target concentrations and it employs a universal format that can detect any infectious agent. 相似文献
992.
Molecular and clinical analysis of ALPL in a cohort of patients with suspicion of Hypophosphatasia 下载免费PDF全文
Jair Tenorio Ignacio Álvarez Leyre Riancho‐Zarrabeitia Gabriel Á. Martos‐Moreno Giorgia Mandrile Monserrat de la Flor Crespo Mikhail Sukchev Mostafa Sherif Iza Kramer María T. Darnaude‐Ortiz Pedro Arias Gema Gordo Irene Dapía Julián Martinez‐Villanueva Rubén Gómez José Manuel Iturzaeta Ghada Otaify Mayte García‐Unzueta Alessandro Rubinacci José A. Riancho Mona Aglan Samia Temtamy Mohamed Abdel Hamid Jesús Argente Víctor L. Ruiz‐Pérez Karen E. Heath Pablo Lapunzina 《American journal of medical genetics. Part A》2017,173(3):601-610
993.
994.
Danielle M. F. Antunes Keri H. Kalmbach Fang Wang Roberta C. Dracxler Michelle L. Seth-Smith Yael Kramer Julia Buldo-Licciardi Fabiana B. Kohlrausch David L. Keefe 《Journal of assisted reproduction and genetics》2015,32(11):1685-1690
Purpose
The effect of age on telomere length heterogeneity in men has not been studied previously. Our aims were to determine the relationship between variation in sperm telomere length (STL), men’s age, and semen parameters in spermatozoa from men undergoing in vitro fertilization (IVF) treatment.Methods
To perform this prospective cross-sectional pilot study, telomere length was estimated in 200 individual spermatozoa from men undergoing IVF treatment at the NYU Fertility Center. A novel single-cell telomere content assay (SCT-pqPCR) measured telomere length in individual spermatozoa.Results
Telomere length among individual spermatozoa within an ejaculate varies markedly and increases with age. Older men not only have longer STL but also have more variable STL compared to younger men. STL from samples with normal semen parameters was significantly longer than that from samples with abnormal parameters, but STL did not differ between spermatozoa with normal versus abnormal morphology.Conclusion
The marked increase in STL heterogeneity as men age is consistent with a role for ALT during spermatogenesis. No data have yet reported the effect of age on STL heterogeneity. Based on these results, future studies should expand this modest sample size to search for molecular evidence of ALT in human testes during spermatogenesis. 相似文献995.
Marek B Kajdaniuk D Janczewska-Kazek E Beniowski M Swietochowska E Kos-Kudła B Ostrowska Z Mazurek U Wilczok T Nowak M Siemińska L Borgiel-Marek H Strzyzewski A Januła A Sierek K Niedzielski Z 《Polskie Archiwum Medycyny Wewn?trznej》2003,109(6):603-608
Fibrosis is the process accompanying majority of chronic diseases of liver, independent of etiological factor and leading to cirrhosis and hepatic failure. Monitoring fibrosis process by liver's biopsy is limited, so many attempts are undertaken to assess concentrations of definite proteins in blood, which could be easily accessible marker of intrahepatic process. It seems, that among others, determinations of blood concentration of aminoterminal propeptide of procollagen III--index of collagen's III synthesis and TGF-beta 1--cytokine of antiproliferative action and inhibiting hepatocytes' growth, yet inducing fibroblasts' growth and stimulating fibrosis process brings out such a possibility. The aim of the study was simultaneous determination of TGF-beta 1 and PIIINP concentration in blood of patients with chronic hepatitis B and C before interferone's therapy in comparison to healthy controls, assessment of the parameters in dependence on stage of liver fibrosis and determination of correlation between TGF-beta 1 and PIIINP. Studies were performed in 40 patients with chronic hepatitis B (CAH B) and 35 patients with chronic hepatitis C (CAH C). Significantly increased serum concentrations of TGF-beta 1 as PIIINP in both groups of patients (CAH B and CAH C; grading 2-3, staging 1-2) in comparison with control group was noted. Significant positive correlation of TGF-beta 1 and PIIINP serum concentrations in both groups of patients was observed. There was not significant changes in PIIINP serum levels in patients with hepatitis B and C in dependence on stage of liver fibrosis (staging 1 vs staging 2) but TGF-beta 1 serum levels was significantly increased in CAH B and C patients with higher stage of liver fibrosis process. On the base of obtained results, it seems that changes in TGF-beta 1 concentrations in blood reflect "grading" and "staging" and can be a marker of intensification of intrahepatic fibrosis process whereas PIIINP levels in blood have rather the relation with "grading". 相似文献
996.
K. Kramer S. Wolf B. Mayer S.A. Schmidt A. Agaimy D. Henne-Bruns U. Knippschild M. Schwab M. Schmieder 《Neoplasia (New York, N.Y.)》2015,17(1):134-140
Currently available data on prognostic implication of additional neoplasms in GIST miss comprehensive information on patient outcome with regard to overall or disease specific and disease free survival. Registry data of GIST patients with and without additional neoplasm were compared in retrospective case series. We investigated a total of 836 patients from the multi-center Ulmer GIST registry. Additionally, a second cohort encompassing 143 consecutively recruited patients of a single oncology center were analyzed. The frequency of additional malignant neoplasms in GIST patients was 31.9% and 42.0% in both cohorts with a mean follow-up time of 54 and 65 months (median 48 and 60 months), respectively. The spectrum of additional neoplasms in both cohorts encompasses gastrointestinal tumors (43.5%), uro-genital and breast cancers (34.1%), hematological malignancies (7.3%), skin cancer (7.3%) and others. Additional neoplasms have had a significant impact on patient outcome. The five year overall survival in GIST with additional malignant neoplasms (n = 267) was 62.8% compared to 83.4% in patients without other tumors (n = 569) (P < .001, HR=0.397, 95% CI: 0.298-0.530). Five-year disease specific survival was not different between both groups (90.8% versus 90.9%). 34.2% of all deaths (n = 66 of n = 193) were GIST-related. The presented data suggest a close association between the duration of follow-up and the rate of additional malignancies in GIST patients. Moreover the data indicate a strong impact of additional malignant neoplasms in GIST on patient outcome. A comprehensive follow-up strategy of GIST patients appears to be warranted. 相似文献
997.
998.
Matthew S. Shupler John K. Kramer Jacquelyn J. Cragg Catherine R. Jutzeler David G.T. Whitehurst 《The journal of pain》2019,20(5):557-565
Recent temporal trends in the population prevalence of chronic pain in Canada on a national and provincial level are unknown. Five cycles of the Canadian Community Health Survey (2000/2001, 2007/2008, 2009/2010, 2011/2012, and 2013/2014) were used to derive population-based estimates of the self-reported prevalence of chronic pain. Sensitivity analyses examined chronic pain prevalence among those reporting no other chronic health conditions. The prevalence of chronic pain among the general Canadian population increased by almost 4.0% (to 21.0%) in 2011/2012, after being in the range of 15.7 to 17.2% from 2000 to 2009/2010. The sudden increase in prevalence was observed 1) across all provinces in Canada, 2) in all age categories, and 3) among Canadians with no other chronic health conditions. Increasing chronic pain prevalence in Canada, most significantly occurring between 2010 and 2012, and including among healthy and young individuals, emphasizes the need for targeted research and resources to help alleviate chronic pain.PerspectiveThis study uncovers a significant increase in chronic pain prevalence in Canada between 2009/2010 and 2011/2012, driven by younger Canadians that are free of the most common chronic health conditions. This discovery emphasizes the importance of further directed research and resources to help mitigate the trend of increasing chronic pain. 相似文献
999.
Pulmonary sequestration is a relatively rare entity comprising a small portion of all congenital pulmonary malformations. Varying clinical techniques have been utilized to manage this disease process including abstaining from surgical intervention, endovascular procedures and operative approaches. We reviewed three case reports with varying presentations, each of which had a favorable outcome with definitive surgical treatment. In conclusion, we recommend that resection should continue to be the standard of care in both adolescent and adult patients with this disease process.KEY WORDS : Pulmonary sequestration, intralobar, case report 相似文献
1000.
ABSTRACT: BACKGROUND: Coronary heart disease (CHD) is a common medical problem in general practice. Due to its chronic character, shared care of the patient between general practitioner (GP) and cardiologist (C) is required. In order to improve the cooperation between both medical specialists for patients with CHD, a local treatment pathway was developed. The objective of this study was first to evaluate GPs' opinions regarding the pathway and its practical implications, and secondly to suggest a theoretical framework of the findings by feeding the identified key factors influencing the pathway implementation into a multi-dimensional model. METHODS: The evaluation of the pathway was conducted in a qualitative design on a sample of 12 pathway developers (8 GPs and 4 cardiologists) and 4 pathway users (GPs). Face-to face interviews, which were aligned with previously conducted studies of the department and assumptions of the theory of planned behaviour (TPB), were performed following a semi-structured interview guideline. These were audio-taped, transcribed verbatim, coded, and analyzed according to the standards of qualitative content analysis. RESULTS: We identified 10 frequently mentioned key factors having an impact on the implementation success of the CHD treatment pathway. We thereby differentiated between pathway related (pathway content, effort, individual flexibility, ownership), behaviour related (previous behaviour, support), interaction related (patient, shared care/colleagues), and system related factors (context, health care system). The overall evaluation of the CHD pathway was positive, but did not automatically lead to a change of clinical behaviour as some GPs felt to have already acted as the pathway recommends. CONCLUSIONS: By providing an account of our experience creating and implementing an intersectoral care pathway for CHD, this study contributes to our knowledge of factors that may influence physicians' decisions regarding the use of a local treatment pathway. An improved adaptation of the pathway in daily practice might be best achieved by a combined implementation strategy addressing internal and external factors. A simple, direct adaptation regards the design of the pathway material (e.g. layout, PC version), or the embedding of the pathway in another programme, like a Disease Management Programme (DMP). In addition to these practical implications, we propose a theoretical framework to understand the key factors' influence on the pathway implementation, with the identified factors along the microlevel (pathway related factors), the mesolevel (interaction related factors), and system- related factors along the macrolevel. 相似文献