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21.
22.
The case of a retarded child with trisomy of the short arm of chromosome 8 associated with translocation between the short arm of chromosome 8 and the long arm of chromosome 22 is reported. Balanced translocation involving the same chromosomes was present in the mother and brother of the propositus. The specific chromosomes involved in the abnormality in this family were identified by use of fluorescence microscopy with quinacrine mustard staining, autoradiography and Giemsa banding. This appears to be the first case report of this anomaly, although trisomy of the short arm of chromosome 9 has been reported previously. 相似文献
23.
The purpose is to incorporate clinically relevant factors such as patient-specific and dosimetric information as well as data from clinical trials in the decision-making process for the selection of prostate intensity-modulated radiation therapy (IMRT) plans. The approach is to incorporate the decision theoretic concept of an influence diagram into the solution of the multiobjective optimization inverse planning problem. A set of candidate IMRT plans was obtained by varying the importance factors for the planning target volume (PTV) and the organ-at-risk (OAR) in combination with simulated annealing to explore a large part of the solution space. The Pareto set for the PTV and OAR was analysed to demonstrate how the selection of the weighting factors influenced which part of the solution space was explored. An influence diagram based on a Bayesian network with 18 nodes was designed to model the decision process for plan selection. The model possessed nodes for clinical laboratory results, tumour grading, staging information, patient-specific information, dosimetric information, complications and survival statistics from clinical studies. A utility node was utilized for the decision-making process. The influence diagram successfully ranked the plans based on the available information. Sensitivity analyses were used to judge the reasonableness of the diagram and the results. In conclusion, influence diagrams lend themselves well to modelling the decision processes for IMRT plan selection. They provide an excellent means to incorporate the probabilistic nature of data and beliefs into one model. They also provide a means for introducing evidence-based medicine, in the form of results of clinical trials, into the decision-making process. 相似文献
24.
Alexander Pushkin Natalia Abuladze Eitan Gross Debra Newman Sergei Tatishchev Ivan Lee Olga Fedotoff Galyna Bondar Rustam Azimov Matt Ngyuen Ira Kurtz 《The Journal of physiology》2004,559(1):55-65
We have recently shown that carbonic anhydrase II (CAII) binds in vitro to the C-terminus of the electrogenic sodium bicarbonate cotransporter kNBC1 (kNBC1-ct). In the present study we determined the molecular mechanisms for the interaction between the two proteins and whether kNBC1 and CAII form a transport metabolon in vivo wherein bicarbonate is transferred from CAII directly to the cotransporter. Various residues in the C-terminus of kNBC1 were mutated and the effect of these mutations on both the magnitude of CAII binding and the function of kNBC1 expressed in mPCT cells was determined. Two clusters of acidic amino acids, L958 DDV and D986 NDD in the wild-type kNBC1-ct involved in CAII binding were identified. In both acidic clusters, the first aspartate residue played a more important role in CAII binding than others. A significant correlation between the magnitude of CAII binding and kNBC1-mediated flux was shown. The results indicated that CAII activity enhances flux through the cotransporter when the enzyme is bound to kNBC1. These data are the first direct evidence that a complex of an electrogenic sodium bicarbonate cotransporter with CAII functions as a transport metabolon. 相似文献
25.
Natural killer (NK)-cell leukemia/lymphoma is a rare entity that has been defined only in recent years. In the Revised European-American Lymphoma and World Health Organization classifications, only the mature NK-cell malignancies are included. However, at least 3 types of precursor NK-cell neoplasms have been reported in the literature. These include myeloid/NK-cell acute leukemia, myeloid/NK-cell precursor acute leukemia, and blastic NK-cell lymphoma/leukemia. These leukemias are characterized by the presence of blasts, which express CD56, in the peripheral blood, bone marrow, lymph nodes, and/or extranodal tissues. We report a case that is morphologically consistent with myeloid/NK-cell acute leukemia but immunologically is myeloid/NK-cell precursor acute leukemia. This case is unique in its cutaneous presentation without involvement of the peripheral blood. Extensive flow cytometric studies were performed on the skin biopsy and bone marrow aspirate specimens, which included many markers that had not been tested before in these entities. The clinical implications of these findings are discussed. 相似文献
26.
John H. Hunts Nobuyoshi Shimizu Tadashi Yamamoto Kumao Toyoshima Glenn T. Merlino Young-hua Xu Ira Pastan 《Somatic Cell and Molecular Genetics》1985,11(5):477-484
The epidermal growth factor (EGF) receptor, along with several oncogene protein products, possesses tyrosine-specific protein kinase activity. Furthermore, the EGF receptor has structural similarity to the putitive v-erb-B transforming protein. Because of these closely shared characteristics, it is important to elucidate the possible involvement of the EGF receptor in malignant transformation. The epidermal carcinoma cell line A431 exhibits an abnormally high number of EGF receptors, which is associated with the presence of translocation chromosome M4. Recently, A431 cells have been shown to contain amplified sequences for the EGF receptor gene(s) and also to produce a variant mRNA which diverges from the normal EGF receptor mRNA at the 3 end. Here we report, using the human EGF receptor cDNA probe pE7, that the chromosome M4 has a six-to sevenfold amplification of the EGF receptor gene. Furthermore, the presence of M4 in somatic cell hybrids correlates with the production of the variant 2.9-kb mRNA. This aberrant mRNA is apparently generated by an intrachromosomal rearrangement which was detected using as a probe a fragment of the pE15cDNA encoding the variant mRNA. 相似文献
27.
Isolation and genetic characterization of human KB cell lines resistant to multiple drugs 总被引:32,自引:0,他引:32
Shin-ichi Akiyama Antonio Fojo John A. Hanover Ira Pastan Michael M. Gottesman 《Somatic Cell and Molecular Genetics》1985,11(2):117-126
Human KB cell lines resistant to high levels of colchicine were isolated by several successive single-step selections. Most of these selection steps resulted in cross-resistance to vincristine, vinblastine, adriamycin, actinomycin D, and puromycin; however, at the highest levels of colchicine resistance, increased cross-resistance to other drugs was not observed. There was no major change in protein synthesis or alteration in protein phosphorylation or [14C]glucosamine labeling patterns accompanying the development of multiple drug resistance as measured by analysis of metabolically labeled proteins on SDS gels. Cell-cell hybridization experiments showed that the colchicine-resistant and multiple drug-resistant phenotypes were incompletely dominant. In addition, colchicine resistance was found to segregate independently from resistance to other drugs in one somatic cell hybrid, suggesting that complex genetic loci are involved in the development of the multiple drug-resistant phenotype. These mutants should be useful for the study of the clinically important problem of multiple drug resistance in human cancer. 相似文献
28.
Brenes Monge Alexander Fernández Elorriaga María Poblano Verástegui Ofelia Valdez Santiago Rosario Martínez Nolasco Manuel A. Yáñez Álvarez Iraís Saturno Hernández Pedro J. 《Maternal and child health journal》2021,25(4):565-573
Maternal and Child Health Journal - To identify and describe the frequency and characteristics of disrespect and abuse practices towards women during facility-based delivery in four hospitals in... 相似文献
29.
Luigi Camera Seigo Kinuya Kayhan Garmestani Martin W. Brechbiel Chuanchu Wu Lee H. Pai Thomas J. McMurry Otto A. Gansow Ira Pastan Chang H. Paik Jorge A. Carrasquillo 《European journal of nuclear medicine and molecular imaging》1994,21(7):640-646
The biodistribution of indium-111/yttrium-88-labeled B3 monoclonal antibody, a murine IgG1k, was evaluated in non-tumor-bearing mice. B3 was conjugated to either 2-(p-SCN-Bz)-6-methyl-DTPA (1B4M) or 2-(p-SCN-Bz)-1,4,7,10 tetraazacyclododecane tetra-acetic acid (2B-DOTA) and labeled with 111In at 1.4–2.4 mCi/mg and 88Y at 0.1–0.3 mCi/mg. Non-tumor-bearing nude mice were co-injected i.v. with 5–10 Ci/4–10 g of 111In/88Y-labeled B3 conjugates and sacrificed at 6 h and daily up to 168 h post-injection. Mice injected with 111In/88Y (IB4M)-B3 showed a similar biodistribution of the two radiolabels in all tissues except the bones, where significantly higher accretion of 88Y than 111In was observed, with 2.8% ± 0.2% vs 1.3% ± 0.16% ID/g in the femur at 168 h, respectively (P<0.0001). In contrast, mice receiving the 111In/88Y-(DOTA)-B3 conjugate showed significantly higher accumulation of 111In than 88Y in most tissues, including the bones, with 2.0% ± 0.1% vs 1.2% ± 0.09% ID/g in the femur at 168 h, respectively (P<0.0001). Whereas the ratios of the areas underneath the curve (%ID × h/g) in the blood, liver, kidney and bone were 0.96, 1.12, 1.13, and 0.74 for 111In/88Y-(IB4M)-B3 and 0.84, 1.23, 1.56, and 1.31 for 111In/88Y (DOTA)-B3, respectively, ratios 1 were observed between 111In-(IB4M)-B3 and 88Y-(DOTA)-B3. In summary, while neither IB4M nor DOTA was equally stable for 111In and 88Y, the fate of 88Y- (DOTA)-B3 could be closely traced by that of 111 In-(IB4M)-B3. 相似文献
30.
Eliasoph I 《Documenta ophthalmologica. Advances in ophthalmology》1999,98(1):87-94
Emil Gruening was the first chief of ophthalmology at the Mount Sinai Hospital, in New York City. The hospital started in
a couple of brownstone tenement buildings in lower Manhattan. Some eye patients were cared for there and many more after moving
to much larger buildings at 66th Street and Lexington Avenue. Gruening came to the United States from Posen in Prussia and
soon afterwards joined the Union army. From Appomattox he returned to New York for completion of his medical studies. He went
to Europe and studied with such notables as von Graefe and Helmholtz. He did cataract surgery with a Graefe knife, with a
nurse at times holding his beard out of the way. He also did ear, nose, and throat surgery. There is a drawing of him doing
a mastoid operation on a child with Abraham Jacobi, the father of American pediatrics, watching him. While at Mt. Sinai, William
Wilmer participated in the transplant of a rabbit eye into a patient, but went on to achieve greater things in the field.
When Gruening died, Wilmer wrote that next to his own father he respected Gruening more than any man he knew. Emil's son Ernest
became Governor of Alaska and Senator from Alaska. When Gruening retired the Eye service was jointly run by Charles H. May
and Carl Koller, but those are other tales to tell.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献