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121.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse.  相似文献   
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123.
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type.  相似文献   
124.
采用三种设计方案考察了白色念珠菌URM3622胞外分泌生产胶原酶的培养条件。首先进行26—2部分因子试验,结果表明转速和底物浓度对胶原酶的产量影响显著。根据以上结果,又设计了两次连续的23全因子分析,结果表明,在pH7.0、转速160r/min、底物浓度2%条件下培养白色念珠菌,发酵所得胶原酶活性最高。在pH8.2、45℃的环境中,胶原酶活性最大。所获胶原酶在pH7.2~8.2及28~45℃范围内稳定。  相似文献   
125.
Mohebbi N, Vargas‐Poussou R, Hegemann SCA, Schuknecht B, Kistler AD, Wüthrich RP, Wagner CA. Homozygous and compound heterozygous mutations in the ATP6V1B1 gene in patients with renal tubular acidosis and sensorineural hearing loss. Distal renal tubular acidosis (dRTA) is characterized by the inability to excrete acid in the renal collecting ducts resulting in inappropriately alkaline urine and hyperchloremic (normal anion gap) metabolic acidosis in the context of a normal (or near‐normal) glomerular filtration rate. Inborn dRTA can be due to autosomal dominant or recessive gene defects. Clinical symptoms vary from mild acidosis, incidental detection of kidney stones or renal tract calcification to severe findings such as failure to thrive, severe metabolic acidosis, and nephrocalcinosis. The majority of patients with recessive dRTA present with sensorineural hearing loss (SNHL). Few cases with abnormal widening of the vestibular aqueduct have been described with dRTA. Mutations in three different genes have been identified, namely SLC4A1, ATP6V1B1, and ATP6V0A4. Patients with mutations in the ATP6V1B1 proton pump subunit develop dRTA and in most of the cases sensorineural hearing loss early in childhood. We present two patients from two different and non‐consanguineous families with dRTA and SNHL. Direct sequencing of the ATP6V1B1 gene revealed that one patient harbors two homozygous mutations and the other one is a compound heterozygous. To our knowledge, this is the first case in the literature describing homozygosity in the same dRTA gene on both alleles.  相似文献   
126.
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
127.
肝癌介入诊疗中DSA血流动力学参数分析初步探讨   总被引:1,自引:0,他引:1  
目的探讨肝癌TACE介入栓塞前肝动脉造影图像上癌灶、癌旁肝组织、背景肝组织之间血流动力学相关参数的差异性。方法本组共34例,男28例,女6例,均为经临床诊断原发性肝癌后第一次行介入诊疗。介入栓塞治疗前均先行肝固有动脉插管造影,采用高压注射器团注对比剂(370mgl/m1)15ml,流率5ml/s,注射后延时0.5s曝光,以4帧/s(fps)帧率持续采集图像15s,获取60(4x15)幅图像。图像处理采用自主开发的图像处理软件DSAanalysis1.0。分别在癌灶的肿瘤染色区、癌旁肝组织及背景肝组织等区域各选定兴趣区(ROI),并生成各区域ROI的时间一密度曲线(TDC),对各TDC进行定量分析,获得与血流动力学相关的参数并对比,相关的参数包括:视频密度增量峰值(AXPV)、达峰时间(TP)、显影持续时间(TD)、TDC升支及降支最大斜率(KmaxU及KmaxD)。结果癌灶、癌旁肝组织、背景肝组织的TD分别为12.97s±0.89、7.75s±0.89、4.99s±0.37;KmaxD分别为36.0s^-1±8.2、90.8s^-1±24.3和142.6S^-1±26.4s。癌灶、癌旁肝组织、背景肝组织的TD及KmaxD两两对比均具有显著性的差异(P〈0.01)。而其他参数三者之间差异无统计学意义(P〉0.05)。结论通过对DSAanalysis1.0软件获得的TDC进行分析,可获得与血流动力学相关参数值,其中TD、KmaxD可在一定程度上反映癌灶、癌旁肝组织及背景肝组织的血流动力学差异。  相似文献   
128.
129.
IL Ackerman  CA Karn  SC Denne  GJ Ensing  CA Leitch 《Pediatrics》1998,102(5):1172-1177
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation.  相似文献   
130.
中西医结合治疗老年高脂血症   总被引:2,自引:1,他引:2  
目的:探讨中西医结合治疗高脂血症的临床疗效。方法:符合高脂血症标准的老年患者120例,随机分为A、B2组各60例,A组采用益肾化淤、利湿化浊为主的中药及西药辛伐他汀片治疗;B组则单纯用辛伐他汀片治疗。治疗前及治疗4周后2组均行全套血脂水平测定。结果:与B组比较,A组血清总胆固醇(TC)及甘油三酯(TG)均明显下降,HDL明显上升(均P〈0.05);A组临床控制率明显高于B组(P〈0.05);治疗后A组患者未见肝功能损害,B组转氨酶及转肽酶轻度异常,2例。停药3个月后,A组复发率低于B组(2.2%、8.8%,P〈0.05)。结论:中西医结合治疗老年高脂血症的临床效果明显优于单一的一种治疗方法,值得临床进一步推广应用。  相似文献   
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