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81.
Richards AJ; Yates JR; Williams R; Payne SJ; Pope FM; Scott JD; Snead MP 《Human molecular genetics》1996,5(9):1339-1343
Stickler syndrome (hereditary arthro-ophthalmopathy) is the commonest
inherited cause of retinal detachment and one of the commonest autosomal
dominant connective tissue dysplasias. There is clinical and locus
heterogeneity with about two thirds of families linked to the gene encoding
type II procollagen (COL2A1). Families with Sticklers syndrome type 1 have
a characteristic congenital vitreous anomaly and are linked without
recombination to markers at the COL2A1 locus. In contrast families with the
type 2 variety have a different vitreo- retinal phenotype and are not
linked to the COL2A1 gene. Type XI collagen is a quantitatively minor
fibrillar collagen related to type V collagen and associated with the more
abundant type II collagen fibrils. A mutation in COL11A2, the gene for
alpha 2 (XI) procollagen, has recently been found in a family described as
having Stickler syndrome, although there was no ocular involvement. Here we
show for the first time that a family with the full Type 2 Stickler
syndrome including vitreous and retinal abnormalities is linked to the
COL11A1 gene and characterise the mutation as a Glycine to Valine
substitution at position 97 of the triple helical domain caused by a single
base G-- >T mutation. These results are the first to provide
confirmation that type XI collagen is an important structural component of
human vitreous. They also support previous work suggesting that mutations
in the genes encoding collagen XI can give rise to some manifestations of
Stickler syndrome, but of these, only mutations in COL11A1 will give the
full syndrome including the vitreo-retinal features.
相似文献
82.
Background
Interventions aimed at behavior change are increasingly being delivered over the Internet. Although research on intervention effectiveness has been widely conducted, their true public health impact as indicated by reach, effectiveness, and use is unclear.Objective
The aim of this paper is to (1) review the current literature on online prevention aimed at lifestyle behaviors, and (2) identify research gaps regarding reach, effectiveness, and use.Methods
A systematic search in PubMed revealed relevant literature published between 2005 and 2012 on Internet-delivered behavior change interventions aimed at dietary behaviors, physical activity, alcohol use, smoking, and condom use. Our search yielded 41 eligible reviews, which were analyzed in terms of reach, effectiveness, and use according to the RE-AIM framework.Results
According to health priorities, interventions are largely targeted at weight-related behaviors, such as physical activity and dietary behavior. Evaluations are predominantly effect-focused and overall effects are small, variable, and not sustainable. Determinants of effectiveness are unclear; effectiveness cannot yet be unambiguously attributed to isolated elements. Actual reach of interventions is undiversified, mostly reaching participants who are female, highly educated, white, and living in high-income countries. One of the most substantial problems in online prevention is the low use of the interventions, a phenomenon seen across all behavior domains.Conclusions
More research is needed on effective elements instead of effective interventions, with special attention to long-term effectiveness. The reach and use of interventions need more scientific input to increase the public health impact of Internet-delivered interventions. 相似文献83.
We report the sequential computed tomography (CT) findings in two fire-eaters after accidental inhalation of pyrofluid. The initial chest radiographic findings were ambiguous and the interpretation of the radiographs was biased by clinical history unrelated to fire eating. On CT, pneumatoceles were the major findings in both patients. The pneumatoceles resolved rapidly, leaving only minimal scarring. Our cases illustrate the sequential evolution of pneumatoceles in fire-eaters after the inhalation of pyrofluid and documents the rapidity with which the lesions regress. The rare accidental inhalation of pyrofluid in fire-eaters may produce a puzzling clinical and radiographic picture and can be confused with other lung disorders. 相似文献
84.
G Cheng ; DS Chiu ; AS Chung ; HF Wong ; MW Chan ; YK Lui ; FM Choy ; JC Chan ; AH Chan ; ST Lam ; TC Fan 《Transfusion》1996,36(4):347-350
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up. 相似文献
85.
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88.
Humphrey RW; O'Brien TR; Newcomb FM; Nishihara H; Wyvill KM; Ramos GA; Saville MW; Goedert JJ; Straus SE; Yarchoan R 《Blood》1996,88(1):297-301
Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed. 相似文献
89.
Characterization of a new non-Hodgkin's lymphoma cell line (NCEB-1) with a chromosomal (11:14) translocation [t(11:14)(q13;q32)] 总被引:2,自引:2,他引:2
Saltman DL; Cachia PG; Dewar AE; Ross FM; Krajewski AS; Ludlam C; Steel CM 《Blood》1988,72(6):2026-2030
A new cell line, NCEB-1, was established by Epstein-Barr virus (EBV) transformation of peripheral blood mononuclear cells from a patient with centroblastic-centrocytic diffuse lymphoma expressing IgM lambda. The transformed cells were lymphoblastoid, with many cells showing a plasmacytoid morphology. The NCEB-1 cells had cytoplasmic Ig (CyIg), with loss of the surface Ig (SIg) expression. Cytogenetic analysis of the cell line demonstrated two clones with variations: a hypodiploid clone, with a complex karyotype including a t(11;14)(q13;q32) similar to the original tumor cells, and a near tetraploid clone with the same markers. Southern blot analysis of DNA from the patient's neoplastic cells and NCEB-1 demonstrated identical Ig heavy chain gene rearrangement, confirming the origin of the cell line. The cell line was not tumorigenic when tested in an in vitro assay using immunosuppressed mice. NCEB-1 has been in continuous culture for 9 months and will be valuable for the in vivo study of non-Hodgkin's lymphoma and EBV transformation. 相似文献
90.
Transformation-associated alterations in interactions between pre-B cells and fibronectin 总被引:5,自引:1,他引:5
Marrow stromal elements produce as yet uncharacterized soluble growth factors that can stimulate the proliferation of murine pre-B cells, although close contact between these two cell types appears to ensure a better pre-B cell response. We have now shown that freshly isolated normal pre-B cells (ie, the B220+, surface mu- fraction of adult mouse bone marrow) adhere to fibronectin (FN) via an RGD cell-attachment site, as shown in a serum-free adherence assay, and they lose this functional ability on differentiation in vivo into B cells (ie, the B220+, surface mu+ fraction). Similarly, cells from an immortalized but stromal cell-dependent and nontumorigenic murine pre-B cell line originally derived from a Whitlock-Witte culture were also found to adhere to fibronectin (FN) via an RGD cell-attachment site. Moreover, in the presence of anti-FN receptor antibodies, the ability of this immortalized pre-B cell line to proliferate when co-cultured with a supportive stromal cell line (M2-10B4 cells) was markedly reduced (down to 30% of control). This suggests that pre-B cell attachment to FN on stromal cells may be an important component of the mechanism by which stromal cells stimulate normal pre-B cell proliferation and one that is no longer operative to control their more differentiated progeny. Two differently transformed pre-B cell lines, both of which are autocrine, stromal-independent, tumorigenic in vivo, and partially or completely differentiation-arrested at a very early stage of pre-B cell development, did not bind to FN. In addition, anti-FN receptor antibodies were much less effective in diminishing the ability of these tumorigenic pre-B cells to respond to M2-10B4 cell stimulation, which could still be demonstrated when the tumorigenic pre-B cells were co- cultured with M2-10B4 cells at a sufficiently low cell density. Analysis of cell surface molecules immunoprecipitated from both the nontumorigenic and tumorigenic pre-B cell lines by an anti-FN receptor antibody showed an increase in very late antigen (VLA) alpha chain(s) in both tumorigenic pre-B cell lines and a decrease in the beta 1 chain in one. Interestingly, all of the pre-B cell lines expressed similar amounts of messenger RNA for the beta 1 chain of the FN receptor. These results suggest that alteration of FN receptor expression on pre-B cells may represent a mechanism contributing to the outgrowth of leukemic pre-B cells with an autocrine phenotype and capable of stromal cell-independent, autonomous growth. 相似文献