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961.
Growth hormone receptor structure, dimerization and function 总被引:1,自引:0,他引:1
PA Kelly MC Postel-Vinay J Finidori M Edery A Sotiropoulos L Goujon N Esposito 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S399):107-111
962.
A spin-echo sequence with 24 echoes (Carr-Purcell-Meiboom-Gill sequence) was evaluated to determine the usefulness of magnetic resonance (MR) in detecting and typing brain tumors. The TEs in these examinations were between 28 and 346 msec, and the TR was 860, 1260, or 1660 msec. The results of the MR examination of 32 histopathologically proved tumors are presented. All but one tumor could be detected by MR. Tumors generally were obvious on MR due to the higher contrast enhancement of these lesions, especially with a TE longer than 100 msec. T2 values calculated from an eight-point fit, however, did not allow discrimination of different tumors, nor did they allow differentiation between tumor, inflammatory tissue, and demyelination. 相似文献
963.
Beris P; Miescher PA; Diaz-Chico JC; Han IS; Kutlar A; Hu H; Wilson JB; Huisman TH 《Blood》1988,72(2):801-805
We have analyzed the sequence of the beta globin gene of a chromosome that is linked to the occurrence of an inclusion body beta-thalassemia characterized in the heterozygote by moderate anemia, severe red cell abnormalities, splenomegaly, inclusion body formation, elevated Hb A2 levels, and an increased in vitro alpha/beta chain synthetic ratio. The data indicate a change in codon 114 from CTG (Leu) to -GG that resulted in a frameshift and the presumed synthesis of an abnormal beta chain that is 156 residues long with a completely different C-terminal amino acid sequence. The change in codon 114 gives a -GGGCCC- sequence that creates a new ApaI site; the resulting 2.6-kilobase fragment has been observed in all subjects with this thalassemia condition. Protein structural analyses failed to demonstrate any trace of the abnormal beta chain, even in reticulocytes and nucleated red cells that were isolated by density gradient centrifugation. The inclusion bodies appear to contain mainly normal alpha chains. It is assumed that the structure of the beta-Geneva chain prevents it from combining with normal alpha chains; this results in a rapid breakdown of the abnormal protein during the early stages of red cell maturation and an accumulation of free alpha chains. 相似文献
964.
Invasive pulmonary aspergillosis and acute leukemia. Limitations in the diagnostic utility of the air crescent sign 总被引:3,自引:0,他引:3
The air crescent sign is regarded as an important diagnostic finding in invasive pulmonary aspergillosis (IPA). This study examined the incidence, clinical importance, and natural history of air crescents in 25 patients with acute leukemia and IPA. Twelve (50%) of the patients had cavities (ten with an air crescent) that appeared an average of 15 days after the initial infiltrate. The diagnostic utility of the air crescent sign was relatively minor; cavities developed after the diagnosis was established in 50% of cases and after therapy was started in 75% of cases. In each case, the pneumonia improved at the time of cavitation. In six patients (50%), the cavities resolved over 2-8 months. Three patients (25%), however, experienced massive hemoptysis. Air crescent formation, previously shown to be dependent on granulocyte recovery, was associated with improved survival (67%) compared with the group without cavitation (8%). In the latter group, the pneumonia in ten (77%) of 13 patients progressed to diffuse disease. In patients with leukemia, the diagnostic value of the air crescent sign is limited by cavities that develop relatively late, as the infection improves after white blood cell recovery; cavities that do not occur in patients who remain neutropenic; and associated hemorrhage, at times life-threatening, that obscures the air crescent. The diagnosis of IPA should not await observation of air crescents in these patients. 相似文献
965.
Ian S. Fraser Gay McCarron 《The Australian & New Zealand journal of obstetrics & gynaecology》1987,27(3):244-247
A double-blind crossover placebo-controlled trial over 6 cycles in 38 Australian women has confirmed that ibuprofen is a valuable drug for the treatment of primary spasmodic dysmenorrhoea. This drug was highly effective when given in a dosage of one 400mg tablet at the first sign of pain or bleeding followed by further 400mg tablets every 4 to 6 hours for the duration of expected symptoms. Side-effects were mild and noted with equal low frequency during placebo treatment. 相似文献
966.
Vertebral hydatid disease: radiological assessment 总被引:4,自引:0,他引:4
967.
Percutaneous retrieval of Kimray-Greenfield vena caval filter 总被引:1,自引:0,他引:1
968.
Inferior joint space arthrograms of the temporomandibular joints of 31 healthy volunteers (62 joints) were obtained to determine normal arthrographic findings. The superior margin of the anterior recess was smooth and flat in 68% of the joints and concave in 32% with the subjects' mouths closed. The concavity was the result of the anterior ridge of the meniscus impinging on the contrast material. The concave impression could be distinguished easily from an anteriorly displaced meniscus on videotaped studies, which demonstrated a smooth transition of contrast material from the anterior to the posterior recess during opening of a subject's mouth. With the mouth open, the anterior recess decreased in size, appearing as a small, crescent-shaped collection of contrast material anterior to the head of the condyle in 52 joints (84%); it remained large in ten joints (16%) at maximal mouth opening. The configuration of the posterior recess was identical to that described previously; however, with the subjects' mouths closed, it was larger than the anterior recess, contrary to most previously reported results. 相似文献
969.
McCarron P Davey Smith G Hattersley AT 《Journal of epidemiology and community health》2004,58(6):517-522
OBJECTIVE: To examine the association between a history of type 2 diabetes and birth weight of offspring and grandchildren. DESIGN: Prospective observational study. Diabetic status, as reported by mothers (F1 generation) was collected on grandparents (F0) of babies (F2) born to mothers (F1) who participated in a study of maternal and child health. Associations between risk of grandparental diabetes and birth weight in mothers (F1) and grandchildren (F2) were analysed using linear and logistic regression. SETTING: Avon: comprising of the city of Bristol and surrounding areas. PARTICIPANTS: 12 076 singleton babies (F2), their parents (F1) and maternal and paternal grandparents (F0). RESULTS: Women (F1) who had no parents with type 2 diabetes had lower birth weights than women with one or two diabetic parents, after controlling for the age of both parents. There was a U shaped association between maternal birth weight and grandmaternal diabetes, but no evidence of an association with grandpaternal diabetes. The grandchildren of maternal grandparents with type 2 diabetes were more likely to be in the top tertile of birth weight than grandchildren of non-diabetics. There was evidence for an inverted U shaped association between birth weight of grandchildren and diabetes in paternal grandmothers. CONCLUSIONS: This is the first study to show intergenerational associations between type 2 diabetes in one generation and birth weight in the subsequent two generations. While the study has limitations mainly because of missing data, the findings nevertheless provide some support for the role of developmental intrauterine effects and genetically determined insulin resistance in impaired insulin mediated growth in the fetus. 相似文献
970.
The authors hypothesized that divergent influences of the APOE epsilon4 allele on ischemic and hemorrhagic stroke survival might result from differences in coagulation profiles. In 49 hemorrhagic stroke patients, epsilon4 carriers had higher partial thromboplastin time ratios (p < 0.01) than non-epsilon4 carriers. Among 529 ischemic stroke patients, increasing epsilon4 allele dose was associated with improved survival (p = 0.03) after adjusting for baseline NIH stroke scale (p = 0.00001) and partial thromboplastin time ratio (p = 0.01). Relative anticoagulation does not fully explain the survival advantage in epsilon4-carrying ischemic stroke patients. 相似文献