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71.
72.
Ohne Zusammenfassung 相似文献
73.
Previously we found human leukocyte antigen (HLA) associations with humoral immunity following a single dose of measles-containing vaccine. In this study, we sought to determine if HLA associations exist with humoral and cellular immunity following a second dose of measles-containing vaccine and if the associations we found with humoral immunity after the first dose persist following a second dose.We recruited a population-based sample of 346 schoolchildren, all who previously received two doses of a measles-containing vaccine. Molecular HLA classes I and II typing as well as humoral and cellular immune assays (measles-specific IgG antibody levels and lymphoproliferative response) were performed in these subjects.We found significant associations with class I HLA-B (p = 0.05) as well as class II HLA-DPB1 (p = 0.01) and -DPA1 (p = 0.03) genes for measles vaccine-induced antibody levels after the second dose. Similarly, we found significant associations with class II HLA-DQB1 (p = 0.05) and -DRB1 (p = 0.01) genes for measles-specific lymphoproliferation after the second dose.While we found HLA associations after the second dose that we previously found after the first dose of measles containing vaccine, fewer alleles had statistically significant associations, suggesting that the second dose had a dampening or extinguishing effect on the HLA associations. It appears that the second dose overcomes HLA restriction through an as yet unknown mechanism. Future studies of HLA associations should consider both the effect of dose and the role that subsequent doses might play on genetic associations found with the response to a first dose. 相似文献
74.
目的探讨肠缺血再灌流损伤时肠内营养与肠粘膜血流改变的关系.方法SD大鼠分为三组,先制作空肠袋,然后将激光多谱勒探头和肠粘膜张力计放置在空肠袋两端,分别向袋内注射丙氨酸、葡萄糖及甘露醇.用动脉夹阻断肠系膜上动脉血流60分后,再恢复灌流60分.分别测定肠粘膜血流量和局部PCO2张力(PrCO2).结果缺血再灌流过程中,与甘露醇组比较,葡萄糖组粘膜血流量显著增加,PrCO2降低.结论缺血再灌流过程中,肠内给予葡萄糖能增加肠粘膜血流量,对缺血再灌流损伤的肠道提供保护作用. 相似文献
75.
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
76.
Oral cyclophosphamide versus chlorambucil in the treatment of patients with membranous nephropathy and renal insufficiency 总被引:4,自引:1,他引:4
Branten AJ; Reichert LJ; Koene RA; Wetzels JF 《QJM : monthly journal of the Association of Physicians》1998,91(5):359-366
We treated patients with idiopathic membranous nephropathy (iMGN) and renal
insufficiency, using: (i) (n = 15) monthly cycles of steroids (1 g
methyl-prednisolone i.v. on three consecutive days, followed by oral
prednisone 0.5 mg/kg/day months 1, 3 and 5) and chlorambucil (0.15
mg/kg/day months 2, 4 and 6); or (ii) (n = 17) oral cyclophosphamide
(1.5-2.0 mg/kg/day for 1 year) and steroids in a comparable dose. The
groups were comparable in age, renal function and levels of proteinuria.
During the 6 months preceding treatment, serum creatinine levels increased
from 148 +/- 50 to 219 +/- 73 mumol/l in the chlorambucil group and from
164 +/- 86 to 274 +/- 126 mumol/l in the cyclophosphamide group. Median
(range) follow-ups were: chlorambucil 38 months (8-71); cyclophosphamide 26
months (5-68) (NS). Renal function improved in both groups, but the
improvement was short-lived in the chlorambucil group; 12 months after
starting treatment, mean serum creatinine was 6.3 mumol/l lower in the
chlorambucil group and 121 mumol/l lower in the cyclophosphamide group (p
< 0.01). Four chlorambucil-treated patients developed ESRD, and five
needed a second course of therapy, whereas only one
cyclophosphamide-treated patient developed ESRD (p < 0.05). Remissions
of proteinuria occurred more frequently after cyclophosphamide treatment
(15/17 vs. 5/15; p < 0.01). Side-effects necessitated interruption of
treatment in six patients on cyclophosphamide and in 11 on chlorambucil (p
< 0.05). In our patients, oral cyclophosphamide was better tolerated
than oral chlorambucil. The suggested greater efficacy of the oral
cyclophosphamide regimen needs to be ascertained by longer follow-up.
相似文献
77.
Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
78.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
79.
Familial hemiplegic migraine: a clinical comparison of families linked and unlinked to chromosome 19 总被引:5,自引:0,他引:5
GM Terwindt RA Ophoff J Haan RR Frants MD Ferrari for the DMGRG 《Cephalalgia : an international journal of headache》1996,16(3):153-155
We compared the clinical characteristics of 50 patients from three unrelated families with familial hemiplegic migraine (FHM) linked to chromosome 19, with those of 20 patients from two families with FHM not linked to chromosome 19. We found no significant differences for age at onset, frequency and duration of attacks, duration of the paresis, and occurrence of basilar migraine symptoms. In the linked families, significantly more patients reported unconsciousness during attacks (39%, vs 15%; p<0.05) and provocation of attacks by mild head trauma (70% vs 40%; p< 0.05). In one linked family patients also displayed chronic progressive cerebellar ataxia, whereas in one unlinked family benign infantile convulsions occurred in addition to FHM. Interestingly, so far an association with cerebellar ataxia was only described in chromosome 19-linked families. FHM linked to chromosome 19 and FHM unlinked to chromosome 19 do not differ with respect to clinical features. 相似文献
80.
Monitoring for undertransfusion 总被引:1,自引:0,他引:1
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components. 相似文献