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111.
National guidelines are released regularly, and professionals are expected to adopt and implement them. However, studies dealing with mental health‐care professionals' views about guidelines are sparse. The aim of the present study was to highlight mental health‐care staff's views on the Swedish national guidelines for ‘psychosocial interventions for schizophrenia or schizophrenia‐type symptoms’ and their implementation. The study took place in the southeast parts of Sweden, and data were collected through five group interviews consisting of 16 professionals working either in the county council or in the municipalities. The transcribed text was analysed by content analysis, revealing two categories. The first category ‘a challenge to the practice of care as known’ reflected that the release of guidelines could be perceived as a challenge to prevailing care and culture. The second category ‘anticipating change to come from above’ mirrored views on how staff expected the implementation process to flow from top to bottom. To facilitate working in accordance with guidelines, we suggest that future guidelines should be accompanied by an implementation plan, where the educational needs of frontline staff are taken into account. There is also a need for policy makers and managers to assume responsibility in supporting the implementation of evidence‐based practice.  相似文献   
112.
Coronary artery aneurysm is an unusual finding at coronary arteriography. We present a case of acute myocardial infarction and a giant aneurysm of the left circumflex coronary artery (CX) in a 70-year-old male with hypertension. The culprit lesion was a thrombus occupying the aneurysm and the distal CX. By an unconventional manoeuvre the thrombus was aspirated via the 7 French guiding catheter. After stent implantation in the distal CX a thrombolysis in myocardial infarction 3 flow was achieved and still present at 2-month follow-up. The patient was prescribed aspirin and clopidogrel as a life-long therapy.  相似文献   
113.
The finding that human factor VIII (fVIII) inhibitor antibodies with C2 domain epitopes interfere with the binding of fVIII to phosphatidylserine (PS) suggested that this is the mechanism by which they inactivate fVIII. We constructed a recombinant C2 domain polypeptide and demonstrated that it bound to all six human inhibitors with fVIII light chain specificity. Thus, some antibodies within the polyclonal anti-light chain population require only amino acids within C2 for binding. Recombinant C2 also partially or completely neutralized the inhibitor titer of these plasmas, demonstrating that anti-C2 antibodies inhibit fVIII activity. Immunoblotting of a series of C2 deletion polypeptides, expressed in Escherichia coli, with inhibitor plasmas showed that the epitopes for human inhibitors consist of a common core of amino acid residues 2248 through 2312 with differing extensions for individual inhibitors. The epitope of inhibitory monoclonal antibody (MoAb) ESH8 was localized to residues 2248 through 2285. Three human antibodies and anti-C2 MoAb NMC-VIII/5 bound to a synthetic peptide consisting of amino acids 2303 through 2332, a PS- binding site, but MoAb ESH8 did not. These antibodies also inhibited the binding of fVIII to synthetic phospholipid membranes of PS and phosphatidylcholine, confirming that the blocked epitopes contribute to membrane binding as well as binding to PS. In contrast, MoAb ESH8 did not inhibit binding. As the maximal function of activated fVIII in the intrinsic factor Xase complex requires its binding to a phospholipid membrane, we propose that fVIII inhibition by anti-C2 antibodies is related to the overlap of their epitopes with the PS-binding site. MoAb ESH8 did not inhibit fVIII binding to PS-containing membranes, suggesting the existence of a second mechanism of fVIII inhibition by anti-C2 antibodies.  相似文献   
114.
Tachibana  N; Raimondi  SC; Lauer  SJ; Sartain  P; Dow  LW 《Blood》1987,70(5):1458-1461
Children with Philadelphia chromosome (Ph+) acute lymphoblastic leukemia (ALL) have a poorer prognosis than do most pediatric patients with ALL. Because of this poor prognosis and the presence of the Ph chromosome, we have asked whether or not Ph + ALL involves a multipotential stem cell. We cultured hematopoietic progenitors from two children with Ph+ ALL and examined individual BFU-E and CFU-GM colonies for the Ph chromosome. We studied cells from two patients after 18 to 34 months of first complete clinical remission; direct cytogenetic analyses showed 26% and 13% Ph+ metaphases in these patients' marrow cells. BFU-E colonies were obtained from light density marrow cells cultured in methylcellulose supplemented with erythropoietin and CFU-GM colonies from agar or methylcellulose cultures stimulated with leukocyte feeder layers. Fifty-seven G-banded metaphases were recovered from 33 colonies. Ten metaphases from seven colonies were Ph+. Ph+ metaphases were found in three of 12 and three of five BFU-E colonies from the two patients. One of 16 CFU-GM colonies from one patient had the Ph+ chromosome; analyzable metaphases were not obtained from CFU-GM of the other patient. No colonies contained both Ph+ and Ph- cells. These results indicate that Ph+ ALL with persistence of Ph+ cells in remission involves a multipotential stem cell for erythroid and granulocyte/macrophage as well as lymphoid lineages. Multipotential stem cell involvement in the pathogenesis of some childhood Ph+ ALL suggests similarities to Ph+ chronic myelocytic leukemia and may contribute to the poor prognosis of these patients.  相似文献   
115.
Dow  LW; Tachibana  N; Raimondi  SC; Lauer  SJ; Witte  ON; Clark  SS 《Blood》1989,73(5):1291-1297
We studied the relationship of direct karyotypes, determined at diagnosis and remission, to Abelson-related tyrosine kinase activity and the cytogenetic features of erythroid and myeloid colonies derived from remission marrow of six children with acute lymphoblastic leukemia (ALL). These patients had either the characteristic Philadelphia chromosome (Ph1) [t(9;22)(q34;q11)] or cytogenetically similar variants with a 22q11 breakpoint but no detectable cytogenetic involvement of 9q34. The findings suggested two distinct subtypes of ALL: one defined by t(9;22)(q34;q11) and expression of P185BCR-ABL tyrosine kinase and one with variant karyotypes and no P185BCR-ABL expression. The former comprises cases with Ph1 + marrow cells and Ph1 + erythroid and (or) myeloid colonies in remission marrow and others in which the t(9;22) is undetectable in remission marrow cells. In the latter subgroup, the disease may reflect more extreme mosaicism with a similar stem cell that is cytogenetically undetectable. Variant karyotypes included a del(22)(q11) in one patient and a t(6;22;15;9) (q21;q11;q?22;q21) in another; in both instances, the malignant blast cells lacked P185BCR- ABL expression. Thus ALL with t(9;22)(q34;q11) should be distinguished from ALL with other involvement of the 22q11 breakpoint by molecular studies including protein expression. The diversity of karyotypic findings in cases with involvement of 22q11 suggests at least two mechanisms of leukemogenesis in patients with ALL defined by this breakpoint.  相似文献   
116.
Effect of platelet-activating factor (PAF) on human platelets   总被引:7,自引:0,他引:7  
Chesney  CM; Pifer  DD; Byers  LW; Muirhead  EE 《Blood》1982,59(3):582-585
The effect of pure synthetic PAF (1-0-alkyl-2-acetyl-sn-glycero-3- phosphorylcholine) was studied in human platelets. PAF (0.2--2.0 micrograms/ml) produced a dose-dependent aggregation in human platelet- rich plasma (PRP) or platelet suspension obtained by gel-filtration (GFP). In addition, PAF (0.8 microgram/ml) induced secretion of 14C- serotonin (45% +/- 10%; mean +/- SD, n = 9) and platelet factor 4 (PF4) (12.89 +/- 3.81 micrograms/10(9) platelets; n = 9) in PRP. Similar results were obtained in GFP. Aggregation and release of 14C-serotonin and PF4 were inhibited by the metabolic inhibitors 2-deoxyglucose (16.7 mM) and antimycin-A (8.3 micrograms/ml), by the membrane-active drugs mepacrine (10 microM) and chlorpromazine (0.025 mM), by PGI2 (5.34 nM), which elevates intracellular c-AMP, by indomethacin (10 microM) or aspirin (100 microM). The ADP scavengers, creatine phosphate and creatine phosphokinase (CP/CPK), inhibited the second wave of aggregation but not secretion. These data suggest that the major effect of PAF on human platelets is mediated through the cyclo-oxygenase pathway and not through a third pathway.  相似文献   
117.
During a 4-year multicenter cooperative study of acquired factor VIII inhibitors in persons with hemophilia A, new inhibitors were detected in 31 of 1,306 patients who entered the study without an inhibitor or the history of an inhibitor. The incidence of new inhibitors was eight per 1,000 patient-years of observation. The factor VIII:C level before inhibitor development was less than or equal to 0.03 U/mL in 29 individuals and 0.06 U/mL and 0.07 U/mL in the remaining two. Factor VIII:Ag levels were measured in 27 individuals and were less than 0.03 U/mL in 23 and 0.05 to 0.11 U/mL in the remaining four. Maximum inhibitor levels ranged from 1.0 to 9,044 Bethesda U/mL. In seven patients under the age of 20, relatively weak inhibitors (none higher than 4.3 Bethesda U/mL) were detected on only a single occasion despite continued factor VIII challenge. In the other 24 patients with inhibitors detected on multiple occasions, 50% had appeared by age 20 and 71% by age 30. Seventeen of the 31 inhibitors, including 12 of 15 with maximum values greater than 10 Bethesda U/mL, developed within 75 exposure days to factor VIII.  相似文献   
118.
This extended review critically compares two edited texts which explore institutional and societal responses to the health risks posed by the presence of HIV infection in blood used for medical purposes. The review is used to raise more general issues about cross-national comparisons and regulatory responses to new risks. The texts reviewed are Bovens, 't Hart and Peters (2001 Bovens, M., 't Hart, P. and Peters, B. G., eds. 2001. Success and Failure in Public Governance. A Comparative Analysis, Cheltenham: Edward Elgar.  [Google Scholar]) Success and Failure in Public Governance. A Comparative Analysis and Feldman and Bayer (1999 Feldman, E. A. and Bayer, R., eds. 1999. Blood Feuds. AIDS, Blood and the Politics of Medical Disaster, New York and Oxford: Oxford University Press.  [Google Scholar]) Blood Feuds. AIDS, Blood and the Politics of Medical Disaster. The review draws a number of conclusions from analysis and comparison of these texts. First, ingrained assumptions (in this case, that transfused blood from unpaid donors is inherently safe) may impede responsiveness to new risks. Second, national political responses to adverse events (in this case HIV infection through medical use of blood products) are not directly related to the adequacy of the regulatory response. Third, the two texts come to somewhat different conclusions about the adequacy of the regulatory response to the contaminated blood crisis. This discrepancy is explained in terms of differences in approach to cross-national comparison.  相似文献   
119.
The factor VIII complex: structure and function   总被引:30,自引:1,他引:30  
Hoyer  LW 《Blood》1981,58(1):1-13
Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIII-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical and immunologic properties, and have unique and essential physiologic functions. While the nature of their interaction and the details of the biochemical structures remain to be determined, the information now available permits a preliminary understanding of the molecular defects in hemophilia and von Willebrand's diseases.  相似文献   
120.
Next-generation sequencing (NGS), an innovative sequencing technology that enables the successful analysis of numerous gene sequences in a massive parallel sequencing approach, has revolutionized the field of molecular biology. Although NGS was introduced in a rather recent past, the technology has already demonstrated its potential and effectiveness in many research projects, and is now on the verge of being introduced into the diagnostic setting of routine laboratories to delineate the molecular basis of genetic disease in undiagnosed patient samples. We tested a benchtop device on retrospective genomic DNA (gDNA) samples of controls and patients with a clinical suspicion of a mitochondrial DNA disorder. This Ion Torrent Personal Genome Machine platform is a high-throughput sequencer with a fast turnaround time and reasonable running costs. We challenged the chemistry and technology with the analysis and processing of a mutational spectrum composed of samples with single-nucleotide substitutions, indels (insertions and deletions) and large single or multiple deletions, occasionally in heteroplasmy. The output data were compared with previously obtained conventional dideoxy sequencing results and the mitochondrial revised Cambridge Reference Sequence (rCRS). We were able to identify the majority of all nucleotide alterations, but three false-negative results were also encountered in the data set. At the same time, the poor performance of the PGM instrument in regions associated with homopolymeric stretches generated many false-positive miscalls demanding additional manual curation of the data.  相似文献   
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