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排序方式: 共有583条查询结果,搜索用时 15 毫秒
1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
2.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
3.
H Boyd J Kaste E Hovi U M Ritanen-Mohammed H Kriinen A de la Chapelle A E Lehesjoki 《Journal of medical genetics》1994,31(3):201-205
We describe two families in whom a pericentric inversion, inv(8)(p23q11), is segregating. No examples of unbalanced karyotypes were encountered. The families originated from neighbouring parishes in western Finland. In one family a mild form of mental retardation segregated. However, this phenotype did not cosegregate with the inversion karyotype. There was no evidence of a higher than average abortion rate in the inversion carriers. Carrier matings produced 19 children with a balanced inversion and 14 children with a normal karyotype, concordant with a 1:1 segregation ratio. Of 13 karyotyped men at risk, 10 were inversion carriers. However, this difference was not statistically different from the expected 1:1 ratio. In females, the inversion carrier to normal ratio was 10:11. 相似文献
4.
5.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
6.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献
7.
8.
Hemophilia A: genetic prediction and linkage studies in all available families in Finland 总被引:1,自引:0,他引:1
Anna-Elina Lehesjoki Pertti Sistonen Vesa Rasi Albert de la Chapelle 《Clinical genetics》1991,39(3):199-209
RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account. 相似文献
9.
AE Boothroyd BVS Murthy A Darbyshire AJ Petros 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(12):1422-1425
Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2 O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced. 相似文献
10.
X linked neonatal myotubular myopathy: one recombination detected with four polymorphic DNA markers from Xq28. 总被引:4,自引:2,他引:4
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A E Lehesjoki E M Sankila J Miao M Somer R Salonen J Rapola A de la Chapelle 《Journal of medical genetics》1990,27(5):288-291
A three generation family with X linked myotubular myopathy (MTM1) was studied with several polymorphic markers from the distal long arm of the X chromosome. A recombination between the disease gene and four markers (loci DXS52, DXS134, DXS15, F8C) from the Xq28 cluster was detected. A new polymorphic marker (U6.2) defining the locus DXS304 in the Xq27-28 region proximal to the Xq28 cluster did not show any recombination with MTM1. These results suggest the following order of loci in distal Xq: cen-DXS42-DXS105-(DXS304, MTM1)-(DXS52, DXS134, DXS15, F8C)-tel. 相似文献