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21.
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
22.
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
23.
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
24.
25.
Sudeshna Paul Taylor Melanson Sumit Mohan Katherine Ross-Driscoll Laura McPherson Raymond Lynch Denise Lo Stephen O. Pastan Rachel E. Patzer 《American journal of transplantation》2021,21(1):314-321
Kidney transplant program performance in the United States is commonly measured by posttransplant outcomes. Inclusion of pretransplant measures could provide a more comprehensive assessment of transplant program performance and necessary information for patient decision-making. In this study, we propose a new metric, the waitlisting rate, defined as the ratio of patients who are waitlisted in a center relative to the person-years referred for evaluation to a program. Furthermore, we standardize the waitlisting rate relative to the state average in Georgia, North Carolina, and South Carolina. The new metric was used as a proof-of-concept to assess transplant-program access compared to the existing transplant rate metric. The study cohorts were defined by linking 2017 United States Renal Data System (USRDS) data with transplant-program referral data from the Southeastern United States between January 1, 2012 and December 31, 2016. Waitlisting rate varied across the 9 Southeastern transplant programs, ranging from 10 to 22 events per 100 patient-years, whereas the program-specific waitlisting rate ratio ranged between 0.76 and 1.33. Program-specific waitlisting rate ratio was uncorrelated with the transplant rate ratio (r = −.15, 95% CI, −0.83 to 0.57). Findings warrant collection of national data on early transplant steps, such as referral, for a more comprehensive assessment of transplant program performance and pretransplant access. 相似文献
26.
27.
Targeting growth factor receptors with fusion toxins. 总被引:1,自引:0,他引:1
Recombinant toxins which bind to growth factor receptors have been prepared and used to kill cells responsible for malignant or autoimmune disease. Our strategy has been to genetically fuse ligands to different forms of Pseudomonas exotoxin which due to mutations or deletions do not bind to normal cells. The resulting recombinant chimeric toxins, in concentrations often less than 1 ng/ml, selectively kill cells expressing the appropriate growth factor receptor. The ligand may be a growth factor, such as transforming growth factor alpha (TGF alpha), interleukin 6 (IL6) or interleukin 2 (IL2), or single chain antigen binding proteins, such as the variable heavy and light regions of the monoclonal antibody anti-Tac. These chimeric toxins kill not only established cell lines but also fresh tumor cells from patients and display anti-tumor activity toward human malignant tumors in nude mice. While clinical trials are beginning with some of these agents, work continues to improve the effectiveness of recombinant chimeric toxins, and to widen the scope of disorders which might be treated by this approach. 相似文献
28.
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
29.
Ira Pastan Lee H. Pai Ulrich Brinkmann David FitzGerald 《Breast cancer research and treatment》1996,38(1):3-9
Summary
Pseudomonas exotoxin has been genetically modified so that it targets cancer cells. This was accomplished by deleting its cell binding domain and replacing it with Fv fragments of antibodies that react with breast, colon, and other cancers. Several recombinant immunotoxins are now in clinical trials.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb. 相似文献
30.
Clinical Guidelines Panel on Erectile Dysfunction: Summary Report on the Treatment of Organic Erectile Dysfunction 总被引:4,自引:0,他引:4
Drogo K. Montague James H. Barada Arnold M. Belker Laurence A. Levine Perry W. Nadig Claus G. Roehrborn Ira D. Sharlip Alan H. Bennett 《The Journal of urology》1996,156(6):2007-2011