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881.
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We use levels-of-processing theory and social facilitation theory to explain the effect of training format and group size on distance and correlation accuracy, leniency-severity, halo, retention of training and pretraining information, and subject arousal. The training factor included frame-of-reference (FOR) training, information only (INFO) training, and no training (NOT). Group size was n?=?1, n?=?6, and n?=?12, respectively. A total of 108 subjects, randomly assigned to one of nine Training?×?Group Size conditions, viewed and rated videotaped lectures. Results indicated that FOR training effected improved retention of training information, improved distance accuracy, and less halo over INFO training or NOT (p  相似文献   
884.
885.
Second malignancies following treatment for osteosarcoma are unusual. Breast cancer occurring in patients with osteosarcoma has been reported following therapeutic chest irradiation. We now report three cases of breast cancer occurring in young women who were successfully treated for osteosarcoma. These women had not received therapeutic chest irradiation and in two of the three women there was no family history of breast cancer. Peripheral blood was available for study from one case. Of import, this case demonstrated a germline mutation in exon 7 of the tumor suppressor gene, p53. The mutation was detected by constant denaturing gradient gel electrophoresis and confirmed by DNA sequencing. In this particular patient, inactivation of the p53 gene may be involved in the development of both the first and second malignancy.  相似文献   
886.
Fifty consecutive adult patients with acute lymphoblastic leukemia (ALL) were treated with an intensive cyclical chemotherapy and the mean received dose of individual cytotoxic drug was retrospectively studied. The median age was 28 years. Twenty-one (43%) had white blood cell (WBC) count over 30 x 10(9)/l. Of the 26 patients with successful cytogenetic studies, ten (28%) had unfavorable clonal chromosomal abnormalities (four Philadelphia chromosome, six others). A high complete remission (CR) rate (86%) was achieved. This was associated with delivery of 100% of the planned dosage of vincristine, prednisone, and daunorubicin at induction. Dose reduction of asparaginase, the fourth drug in the induction protocol, was recorded in 20 (40%) patients. The CR rate of these patients was not adversely affected. Dose reduction was recorded during consolidation (38 of 43 remitters) and maintenance (18 of 20 remitters) as a result of treatment toxicity. The mean received dose of teniposide, Ara-C, asparaginase, mercaptopurine, and methotrexate was 73% (SD 7%), 73% (SD 7%), 62% (SD 41%), 65% (SD 15%) and 73% (SD 17%) of the planned dosage, respectively. The 5-year overall survival and leukemia-free survival (LFS) were 11% (95% CI: 0-27%) and 13% (95% CI: 0-26%), respectively. Even standard-risk patients had 4-year LFS of only 26% (95% CI: 0-57%). Among 36 remitters not withdrawn from consolidation, there were 29 treatment failures after a median follow-up of 42 months; 25 (86%) of these were leukemia relapse, three (10%) were toxic death during consolidation, and one patient (4%) died from therapy-related myelodysplastic syndrome. We postulate inadequate drug delivery during postremission therapy contributed to the high relapse rate in the whole group as well as the standard-risk patients.  相似文献   
887.
The single gene reassortant virus that derives its PB2 gene from the avian influenza A/Mallard/NY/78 virus and remaining genes from the human influenza A/Los Angeles/2/87 virus exhibits a host range restriction (hr) phenotype characterized by efficient replication in avian tissue and failure to produce plaques in mammalian Madin-Darby canine kidney cells. The hr phenotype is associated with restriction of viral replication in the respiratory tract of squirrel monkeys and humans. To identify the genetic basis of the hr phenotype, we isolated four phenotypic hr mutant viruses that acquired the ability to replicate efficiently in mammalian tissue. Segregational analysis indicated that the loss of the hr phenotype was due to a mutation in the PB2 gene itself. The nucleotide sequences of the PB2 gene of each of the four hr mutants revealed that a single amino acid substitution at position 627 (Glu-->Lys) was responsible for the restoration of the ability of the PB2 single gene reassortant to replicate in Madin-Darby canine kidney cells. Interestingly, the amino acid at position 627 in every avian influenza A virus PB2 protein analyzed to date is glutamic acid, and in every human influenza A virus PB2 protein, it is lysine. Thus, the amino acid at residue 627 of PB2 is an important determinant of host range of influenza A viruses.  相似文献   
888.
Using immunocytochemical and Western blotting techniques we have demonstrated the presence of abnormally high levels of p53 protein in 8/24 (33%) of human squamous cell carcinomas (SCC) and 9/18 (50%) of SCC cell lines. There was a correlation between the immunocytochemical results obtained with eight SCC samples and their corresponding cell lines. Direct sequencing of PCR-amplified, reverse transcribed, p53 mRNA confirmed the expression of point mutations in six of the positive cell lines and detected in-frame deletions in two others. We also detected two stop mutations and three out-of-frame deletions in five lines which did not express elevated levels of p53 protein. Several of the mutations found in SCC of the tongue (3/7) were in a region (codons 144-166) previously identified as being a p53 mutational hot spot in non-small cell lung tumours (Mitsudomi et al., 1992). In 11/13 cases only the mutant alleles were expressed suggesting loss or reduced expression of the wild type alleles in these cases. Six of the mutations were also detected in the SCCs from which the lines were derived, strongly suggesting that the mutations occurred, and were selected, in vivo. The 12th mutation GTG-->GGG (valine-->glycine) at codon 216 was expressed in line SCC-12 clone B along with an apparently normal p53 allele and is to our knowledge a novel mutation. Line BICR-19 also expressed a normal p53 allele in addition to one where exon 10 was deleted. Additionally 15 of the SCC lines (including all of those which did not show elevated p53 protein levels) were screened for the presence of human papillomavirus types 16 and 18 and were found to be negative. These results are discussed in relation to the pathogenesis of SCC and the immortalisation of human keratinocytes in vitro.  相似文献   
889.
Twenty-five patients with liver cirrhosis and portal hypertension were admitted for creation of a transjugular intrahepatic portosystemic shunt (TIPS). The procedure was successful in 22 patients (technical success 88%). The mean portal pressure gradient was lowered from 24.5 mmHg before to 11.4 mmHg after TIPS. Two early and three late occlusions were observed (primary patency rate 78%). The rate of secondary interventions was 41%. Five times a hepatic vein stenosis was dilated and stented, two times an occluded shunt was recanalized, two times a new shunt was created parallel to an occluded (secondary patency rate within a maximum of 16 months 95%). In two patients sepsis occurred which was effectively treated with antibiotics, two patients died shortly after TIPS due to hepatorenal syndrome and hepatic failure, respectively. There was no recurrent bleeding. Two patients developed hepatic encephalopathy; both improved after protein restriction. The authors conclude that TIPS is an alternative procedure to shunt surgery, especially for patients who cannot benefit from sclerotherapy.  相似文献   
890.
A concordance analysis between the Center for Epidemiologic Studies Depression Scale (CES-D) and the National Institute of Mental Health (NIMH) Diagnostic Interview Schedule (DIS) for current major depression was conducted using data from Cuban Americans and Puerto Rican respondents to the Hispanic Health and Nutrition Examination Survey (HHANES). Overall agreement between the two depression measures was relatively high, which suggested that the CES-D might be appropriate as a first-stage screening instrument for community-based surveys of clinical depression. Female gender and indicators of social class (education, income, poverty index, and employment) were related to low specificity and low agreement. The estimated cutoff points of the CES-D that best predicted DIS current major depression were different between the two ethnic groups; 17 for Cuban Americans, and 20 for Puerto Ricans. A receiver operating characteristics (ROC) curve analysis revealed that the traditional method of defining CES-D cases by summing the scores for each item was superior to counting only the persistent symptoms, that is, those present nearly everyday.  相似文献   
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