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排序方式: 共有1774条查询结果,搜索用时 15 毫秒
41.
Rea IM Mc Dowell I McMaster D Smye M Stout R Evans A;MONICA group 《Mechanisms of ageing and development》2001,122(13):1367-1372
The ApoE gene has three alleles coding for the proteins apoE2, apoE3 and apoE4. E4 has been reported to be associated with hypercholesteraemia, ischaemic heart disease, age-related cognitive decline and Alzheimer's disease. Conversely, the E2 allele has been associated with longevity in French centenarians and their siblings. In this study, we have assessed any shift in the ApoE genotypes in nonagenarian subjects from Belfast where there is a high intrinsic incidence of cardiovascular disease. ApoE phenotypes were determined by electrofocusing and immunoblotting in 114 Senieur-approximated subjects >90 years old and compared with 2071 subjects, 30--65 years of age, recruited from the same geographical area by the MONItoring of CArdiovascular trends study group in Belfast (MONICA). The E4 allele was reduced in the nonagenarian group (X(2)=11.1; P=0.0006), the E3 unchanged and E2 frequency was increased (X(2)=4.0; P=0.047). These results suggest that longevity is negatively associated with the E4 allele and may be associated with carriage of E2. 相似文献
42.
Friedmann PD Rose JS Swift R Stout RL Millman RP Stein MD 《Alcoholism, clinical and experimental research》2008,32(9):1652-1660
Background: Trazodone is a commonly prescribed off-label for sleep disturbance in alcohol-dependent patients, but its safety and efficacy for this indication is unknown.
Methods: We conducted a randomized, double-blind, placebo-control trial of low-dose trazodone (50 to 150 mg at bedtime) for 12 weeks among 173 alcohol detoxification patients who reported current sleep disturbance on a validated measure of sleep quality or during prior periods of abstinence. Primary outcomes were the proportion of days abstinent and drinks per drinking day over 6-months; sleep quality was also assessed.
Results: Urn randomization balanced baseline features among the 88 subjects who received trazodone and 85 who received placebo. The trazodone group experienced less improvement in the proportion of days abstinent during administration of study medication (mean change between baseline and 3 months: −0.12; 95% CI: −0.15 to −0.09), and an increase in the number of drinks per drinking day on cessation of the study medication (mean change between baseline and 6 months, 4.6; 95% CI: 2.1 to 7.1). Trazodone was associated with improved sleep quality during its administration (mean change on the Pittsburgh Sleep Quality Index between baseline and 3 months: −3.02; 95% CI: −3.38 to −2.67), but after it was stopped sleep quality equalized with placebo.
Conclusions: Trazodone, despite a short-term benefit on sleep quality, might impede improvements in alcohol consumption in the postdetoxification period and lead to increased drinking when stopped. Until further studies have established benefits and safety, routine initiation of trazodone for sleep disturbance cannot be recommended with confidence during the period after detoxification from alcoholism. 相似文献
Methods: We conducted a randomized, double-blind, placebo-control trial of low-dose trazodone (50 to 150 mg at bedtime) for 12 weeks among 173 alcohol detoxification patients who reported current sleep disturbance on a validated measure of sleep quality or during prior periods of abstinence. Primary outcomes were the proportion of days abstinent and drinks per drinking day over 6-months; sleep quality was also assessed.
Results: Urn randomization balanced baseline features among the 88 subjects who received trazodone and 85 who received placebo. The trazodone group experienced less improvement in the proportion of days abstinent during administration of study medication (mean change between baseline and 3 months: −0.12; 95% CI: −0.15 to −0.09), and an increase in the number of drinks per drinking day on cessation of the study medication (mean change between baseline and 6 months, 4.6; 95% CI: 2.1 to 7.1). Trazodone was associated with improved sleep quality during its administration (mean change on the Pittsburgh Sleep Quality Index between baseline and 3 months: −3.02; 95% CI: −3.38 to −2.67), but after it was stopped sleep quality equalized with placebo.
Conclusions: Trazodone, despite a short-term benefit on sleep quality, might impede improvements in alcohol consumption in the postdetoxification period and lead to increased drinking when stopped. Until further studies have established benefits and safety, routine initiation of trazodone for sleep disturbance cannot be recommended with confidence during the period after detoxification from alcoholism. 相似文献
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45.
Brunner G; Metz CN; Nguyen H; Gabrilove J; Patel SR; Davitz MA; Rifkin DB; Wilson EL 《Blood》1994,83(8):2115-2125
Basic fibroblast growth factor (bFGF) is a hematopoietic cytokine that stimulates stromal and stem cell growth. It binds to a glycosylphosphatidylinositol (GPI)-anchored heparan sulfate proteoglycan on human bone marrow (BM) stromal cells. The bFGF- proteoglycan complex is biologically active and is released by addition of exogenous phosphatidylinositol-specific phospholipase C. In this study, we show the presence of an endogenous GPI-specific phospholipase D (GPI-PLD) that releases the bFGF-binding heparan sulfate proteoglycan and the variant surface glycoprotein (a model GPI-anchored protein) from BM cultures. An involvement of proteases in this process is unlikely, because released proteoglycan contained the GPI anchor component, ethanol-amine, and protease inhibitors did not diminish the release. The mechanism of release is likely to involve a GPI-PLD and not a GPI-specific phospholipase C, because the release of variant surface glycoprotein did not reveal an epitope called the cross- reacting determinant that is exposed by phospholipase C-catalyzed GPI anchor cleavage. In addition, phosphatidic acid (which is specifically a product of GPI-PLD-catalyzed anchor cleavage) was generated during the spontaneous release of the GPI-anchored variant surface glycoprotein. We also detected GPI-PLD-specific enzyme activity and mRNA in BM cells. Therefore, we conclude that an endogenous GPI-PLD releases bFGF-heparan sulfate proteoglycan complexes from human BM cultures. This mechanism of GPI anchor cleavage could be relevant for mobilizing biologically active bFGF in BM. An endogenous GPI-PLD could also release other GPI-anchored proteins important for hematopoiesis and other physiologic processes. 相似文献
46.
For many patients with end-stage heart failure, heart transplantation is the only remaining option to prolong survival and provide symptom relief. Transthoracic echo is the modality of choice in assessing a patient for potential left ventricular assist device (LVAD) insertion. There are currently no guidelines available, and assessing this specific patient population can prove extremely challenging. As such, an understanding of LVAD mechanism, the important physiological consequences of device implantation together with the related echocardiographic examination is vital to accurately and effectively gauge correct patient selection and also improve implantation success. This review aims to highlight the common devices implanted, how these devices affect cardiac physiology and hemodynamics, and therefore discuss the major echocardiographic variables that should be assessed predevice implantation. (Echocardiography 2012;29:52-58). 相似文献
47.
Evidence-based guidelines and subsequent studies support the effectiveness of counselling and pharmacotherapy as first-line smoking cessation interventions. Gender is one of many factors that may have an impact on the efficacy of smoking cessation interventions. There is only very limited evidence, however, to answer the question of how gender influences the effectiveness of smoking cessation interventions. Research does suggest that concern about weight gain is related to women's confidence in their ability to stop smoking and this should be kept in mind when designing interventions. In the meantime, any client who indicates a desire to stop smoking should be offered one of the smoking cessation interventions that are already available. 相似文献
48.
A previous report described a prime-boost immunization strategy using plasmid and modified vaccinia virus Ankara (MVA) vectors expressing herpes simplex virus 2 glycoprotein D (gD). Enhanced humoral and cellular immune responses were elicited by the prime-boost combination compared to plasmid DNA immunization alone. Surprisingly, a more diverse antibody isotype response, and a greater antibody and cellular immune response, was obtained if the gD MVA vector was used as the priming immunization rather than the gD plasmid vector. The present report evaluates the use of a needle-free delivery platform (Biojector) for delivery of plasmid and MVA gD-expressing vectors in a prime-boost immunization strategy. Needle-free delivery of both plasmid and MVA gD expression vectors was efficient, reproducible, and elicited a strong immune response in immunized mice. Biojector delivery of plasmid DNA was able to evoke a broader isotype response and cellular immune response than that obtained by gene gun delivered plasmid DNA. Further, DNA priming by Biojector delivery as part of a prime-boost procedure with MVA-gD2 resulted in a diverse antibody isotype distribution and enhanced cellular immune responses, similar to the responses obtained when MVA-gD2 was used as the priming immunization. Thus, needle-free delivery of plasmid DNA may provide additional flexibility and options for effective prime-boost vaccination. 相似文献
49.
KJ Champion C Bunag AL Estep JR Jones CH Bolt RC Rogers KA Rauen DB Everman 《Clinical genetics》2011,79(5):468-474
Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation. 相似文献
50.
E Waanders H Venselaar RHM Te Morsche DB De Koning PS Kamath VE Torres S Somlo JPH Drenth 《Clinical genetics》2010,78(1):47-56
Waanders E, Venselaar H, te Morsche RHM, de Koning DB, Kamath PS, Torres VE, Somlo S, Drenth JPH. Secondary and tertiary structure modeling reveals effects of novel mutations in polycystic liver disease genes PRKCSH and SEC63. Polycystic liver disease (PCLD) is characterized by intralobular bile duct cysts in the liver. It is caused by mutations in PRKCSH, encoding hepatocystin, and SEC63, encoding Sec63p. The main goals of this study were to screen for novel mutations and to analyze mutations for effects on protein structure and function. We screened 464 subjects including 76 probands by direct sequencing or conformation‐sensitive capillary electrophoresis. We analyzed the effects of all known and novel mutations using a combination of splice site recognition, evolutionary conservation, secondary and tertiary structure predictions, Poly Phen , and p Mut and sift . We identified a total of 26 novel mutations in PRKCSH (n = 14) and SEC63 (n = 12), including four splice site mutations, eight insertions/ deletions, six non‐sense mutations, and eight missense mutations. Out of 48 PCLD mutations, 13 were predicted to affect splicing. Most mutations were located in highly conserved regions and homology modeling for two domains of Sec63p showed severe effects of the residue substitutions. In conclusion, we identified 26 novel mutations associated with PCLD and we provide in silico analysis in order to delineate the role of these mutations. 相似文献