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991.
Sofikitis N; Miyagawa I; Yamamoto Y; Loutradis D; Mantzavinos T; Tarlatzis V 《Human reproduction update》1998,4(3):197-212
This review refers to the evolution of ooplasmic injectionsof round spermatid nuclei ROSNI) or intact round spermatidsROSI). Conclusions from their preliminary application in thehamster, rabbit, mouse and human are discussed. Criteria foridentification of round spermatids and guidelines/quality controlfor application of ROSNI/ROSI techniques are emphasized. Althoughall the animal offspring and the human newborns delivered afterROSNI/ROSI are healthy additional research efforts are necessaryto confirm the safety of these procedures and improve theiroutcome 相似文献
992.
Gil I Wolfe Dennis K Burns Daniel Krampitz Richard J Barohn 《Neuromuscular disorders : NMD》1997,7(8):536-538
We describe the presence of cylindrical spirals on muscle biopsy from a 31-year-old man who developed rhabodomyolysis following a long run. He had a prior history of exertional cramps and myoglobinuria. His maternal grandfather had similar symptoms. Transmission electron micrographs demonstrated continuity between the lamellae of the cylindrical spirals and native myofilaments. Whether these unusual structures confer a derangement in myofilament function is uncertain. 相似文献
993.
994.
Begoa Granadino Luiz O. F. Penalva Michael R. Green Jun Valcrcel Lucas Snchez 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(14):7343-7348
The protein Sex-lethal (SXL) controls pre-mRNA splicing of two genes involved in Drosophila sex determination: transformer (tra) and the Sxl gene itself. Previous in vitro results indicated that SXL antagonizes the general splicing factor U2AF65 to regulate splicing of tra. In this report, we have used transgenic flies expressing chimeric proteins between SXL and the effector domain of U2AF65 to study the mechanisms of splicing regulation by SXL in vivo. Conferring U2AF activity to SXL relieves its inhibitory activity on tra splicing but not on Sxl splicing. Therefore, antagonizing U2AF65 can explain tra splicing regulation both in vitro and in vivo, but this mechanism cannot explain splicing regulation of Sxl pre-mRNA. These results are a direct proof that Sxl, the master regulatory gene in sex determination, has multiple and separable activities in the regulation of pre-mRNA splicing. 相似文献
995.
STOWELL L. I.; FAWCETT J. P.; BROOKE M.; ROBINSON G. M.; STANTON W. R. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1997,32(4):507-516
Serum levels of carbohydrate-deficient transferrin (CDT) weremeasured in subjects of two independent studies using two differentcommercial kits. The kits measure CDT either as a percentageof total transferrin (AXIS %CDTTM, AXIS Biochemicals AS, Norway),or as the absolute amount (CDTectTM, Pharmacia, Sweden). Ina population of males (mean age 41 years) consisting of alcoholics,heavy, moderate and non-drinkers, a strong correlation was foundbetween AXIS %CDT and CDTect results (r=0.92, n=58, P<0.001).Sensitivity and specificity in detecting chronic alcoholic drinkingof over 60 g/day were 78 and 94% for the AXIS assay, and 83and 88% for the CDTect assay, respectively. In a populationfrom a birth cohort study, consisting of 21-year-old males andfemales with less excessive alcohol consumption, the correlationbetween AXIS %CDT and CDTect CDT was weaker but still statisticallysignificant (r=0.46. n=212, =<0.001). In this population,with specificities >83% in detecting alcohol consumptionlevels of 相似文献
996.
997.
W. Kreuz C. Escuriola-Ettingshausen I. Martinez-Saguer T. Güngr B. Kornhuber 《Vox sanguinis》1996,70(Z1):2-8
One of the most serious complications of the treatment of haemophilia A is the development of inhibitors. Former studies mostly considered the prevalence of inhibitor development, thus underestimating its true risk. Prevalences ranged widely (7–18%) probably due to the populations studied and the study design. Recent prospective previously untreated patients (PUP) studies were more comparable because of similar study designs. Eight PUP studies regarding the incidence of factor VIII inhibitors were analyzed: The inhibitor incidences (Independent of severity of haemophilia) ranged from 18.4 to 28%. Evaluating only severe haemophiliacs (factor VIII<2%) significantly higher incidences were found. After 9–36 exposure days (as medians inhibitor development occurred at 0.8-3.3 years of age (as medians). 相似文献
998.
999.
Prospective study of antigenemia,plasma viremia and lymphocytic viremia in HIV-infected hemophiliacs
S. Melón Garcia M. de Oña Navarro C. Rodriguez Pinto M. Fernández Urgellés A. Martinez Gutierrez P. de la Iglesia F. J. Mendez García 《European journal of clinical microbiology & infectious diseases》1995,14(5):400-405
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05). 相似文献
1000.