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排序方式: 共有575条查询结果,搜索用时 9 毫秒
1.
Myosin VIIA gene: heterogeneity of the mutations responsible for Usher syndrome type IB 总被引:8,自引:1,他引:8
Levy G; Levi-Acobas F; Blanchard S; Gerber S; Larget-Piet D; Chenal V; Liu XZ; Newton V; Steel KP; Brown SD; Munnich A; Kaplan J; Petit C; Weil D 《Human molecular genetics》1997,6(1):111-116
Usher syndrome is recognized as the most frequent cause of hereditary
deaf-blindness. Usher syndrome type I (USH1), the most severe form of the
disease, is characterized by profound congenital sensorineural deafness,
constant vestibular dysfunction, and retinitis pigmentosa of prepubertal
onset. This form is genetically heterogeneous and five loci (USH1A-E) have
been mapped thusfar. However, only the gene responsible for USH1 B (which
accounts for approximately 75% of USH1 cases) has been characterized. It
encodes a long-tailed unconventional myosin, myosin VIIA, with a predicted
2215 amino acid sequence. Primers covering the complete myosin VIIA coding
sequence as well as the 3' non coding sequence were designed, allowing
direct sequence analysis of each of the 48 coding exons and flanking splice
sites in seven patients affected by USH1. Four novel mutations were thereby
identified. The possibility should now be considered of a sequence-based
prenatal diagnosis in some of the families affected by this very severe
form of Usher syndrome.
相似文献
2.
Evolutionary silencing of the human elastase I gene (ELA1) 总被引:6,自引:0,他引:6
3.
Aravind Krishnan Joshua Hsu Jinny S. Ha Stephen R. Broderick Pali D. Shah Robert SD. Higgins Christian A. Merlo Errol L. Bush 《American journal of surgery》2021,221(4):731-736
PurposeWe aimed to assess the prognostic value of Neutrophil to Lymphocyte Ratio (NLR) on long-term outcomes and graft dysfunction after lung transplantation.MethodsWe retrospectively reviewed all patients receiving a lung transplant at our institution from 2011 to 2014. The primary exposure was elevated NLR at the time of transplant, defined by NLR>4. The primary outcomes were graft failure and three-year all-cause mortality. Multivariate logistic regression and Kaplan-Meier survival analysis were used to analyze outcomes.Results95 patients were included. 40 patients (42%) had an elevated NLR. Elevated NLR was associated with graft failure (OR: 4.7 [1.2–18.8], p = 0.02), and three-year mortality (OR: 5.4 [1.3–23.2], p = 0.03) on multivariate logistic regression. Patients with elevated NLR demonstrated significantly lower survival on Kaplan-Meier analysis (50% versus 74%, p = 0.02). The c-statistic for our multivariate model was 0.91.ConclusionElevated neutrophil to lymphocyte ratio is associated with poor long-term survival and graft failure after lung transplantation. 相似文献
4.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
5.
The extreme variability of human immunodeficiency virus type 1 (HIV-1) makes it possible to conduct transmission studies on the basis of genetic analysis and to trace global and local patterns in the spread of the virus. Two such patterns are discussed in this paper. First, in many European countries (e.g., Scotland and Germany), homosexual men tend to be infected with a subtly different variant of HIV-1 than intravenous drug users. In other European countries (e.g., Norway and Sweden), a distinction is also found between the two risk groups; but based on available data, the distinction is a different one. The second pattern is a worldwide tendency for homosexual men in many different geographic regions around the world to carry HIV-1 subtype B, the variant that is most prevalent in the Americas, Europe, and Australia. In contrast, people infected via other routes (mostly heterosexual contact) in those same countries carry a mixture of other subtypes. Biologic differences between the viruses infecting different risk groups have not been found; the most likely explanation for the findings is different epidemiologic patterns. Although data are still scarce, the authors attempt to use these patterns in the reconstruction of the worldwide spread of the HIV epidemic. 相似文献
6.
Non-typhoid Salmonella gastroenteritis 总被引:2,自引:0,他引:2
7.
Jolianne M. Rijks Mardik F. Leopold Susanne Kühn Ronald in t Veld Fred Schenk Allix Brenninkmeijer Sander J. Lilipaly Mnika Z. Ballmann Leon Kelder Job W. de Jong Wouter Courtens Roy Slaterus Erik Kleyheeg Sandra Vreman Marja J.L. Kik Andrea Grne Ron A.M. Fouchier Marc Engelsma Mart C.M. de Jong Thijs Kuiken Nancy Beerens 《Emerging infectious diseases》2022,28(12):2538
We collected data on mass mortality in Sandwich terns (Thalasseus sandvicensis) during the 2022 breeding season in the Netherlands. Mortality was associated with at least 2 variants of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b. We report on carcass removal efforts relative to survival in colonies. Mitigation strategies urgently require structured research. 相似文献
8.
Increasing antigenic and genetic diversity of the V3 variable domain of the human immunodeficiency virus envelope protein in the course of the AIDS epidemic. 总被引:15,自引:1,他引:15 下载免费PDF全文
C L Kuiken G Zwart E Baan R A Coutinho J A van den Hoek J Goudsmit 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(19):9061-9065
Population-wide variation in genomic RNA of human immunodeficiency virus type 1 (HIV-1) encompassing the V3 loop of the envelope protein was studied in serum samples of 74 newly infected individuals from three Dutch cohorts: 30 homosexual men, 32 drug users, and 12 hemophiliacs. During acute infection, HIV-1 RNA sequences present in serum are relatively homogeneous, which makes direct sequencing feasible. This offered an opportunity to study the infecting virus variants before mutations had accumulated in the new host. The sampling dates ranged from 1980 to 1991, thus spanning the entire AIDS epidemic in The Netherlands. The diversity in the sequenced region increased over time in both the homosexual and the drug-user risk groups. Furthermore, this increase was associated with an increase in antigenic variation, as witnessed by serum reactivity to a V3 peptide panel. Despite this diversification, some 1990 sequences still closely resembled the earliest 1980 sequence, making ancestral inferences problematic. No evidence was found of a change in the master sequence of the virus quasi-species over time. At the amino acid level, no risk-group-associated variation was found, but at the nucleotide level, the drug-user and homosexual/hemophiliac sequences could be distinguished on the basis of a single silent nucleotide change in the sequence encoding the tip of the V3 loop. Hemophiliac sequences could not be distinguished from those of homosexuals. In spite of the large and increasing genetic variability, all sequences were more similar to the European/American HIV consensus sequence than to that of non-Western strains. 相似文献
9.
Use of a radioimmunoassay to quantify thrombospondin 总被引:8,自引:0,他引:8
Results of radioimmunoassay procedures applied to samples containing thrombospondin indicated that reliable values are obtained either in saline or in plasma. Plasma levels in apparently normal individuals ranged from approximately 20 to 300 ng/ml. The mean for 20 individuals was 175 ng/ml. Plasma specimens stored either refrigerated at 4 degrees C or frozen at -80 degrees C showed significantly diminished thrombospondin levels over a period of 90 days. Serum levels of thrombospondin were found to range from 10,000 to 30,000 ng/ml. 相似文献
10.