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21.
Suppression of acute lymphoblastic leukemia by the human wild-type p53 gene.   总被引:11,自引:0,他引:11  
Independent mutations in both alleles of the p53 tumor suppressor gene are a frequent finding in human T-cell acute lymphoblastic leukemia (T-ALL) cell lines and in the cells of some T-ALL patients in relapse. One major goal of studying the status of p53 (and other tumor suppressor genes) in human cancer is to facilitate the suppression of the tumorigenic phenotype through the restoration of the expression of the wild-type allele. While the efficient insertion of a suppressor into all cells of solid/metastatic human tumors may at present be impossible, insertion into leukemia cells may be feasible due to the accessibility of the leukemia cells in the body. To examine the feasibility of suppressing the tumorigenicity of human T-leukemia cells, the human T-ALL cell line Be-13, which lacks endogenous p53 protein, was infected with a recombinant retrovirus encoding the wild-type allele of human p53 (hwtp53). Expression of p53 reduced the growth rate of infected Be-13 cells in vitro, suppressed colony formation in methylcellulose cultures, and abrogated their tumorigenic phenotype in nude mice in vivo. These results suggest that suppression of the leukemic phenotype of relapse T-ALL-derived Be-13 cells is feasible. Acute leukemia cell suppression via high-efficiency infection with retroviruses encoding wtp53 may be feasible and beneficial in T-ALL cases as part of a bone marrow transplantation regimen in an effort to reduce the frequency of posttransplantation relapse.  相似文献   
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F Girardi  P Fuchs  J Haas 《Cancer》1992,69(10):2502-2504
Human papillomavirus (HPV) type 16 DNA is frequent in invasive cervical cancers. Among 43 patients with invasive cervical cancer, HPV-16-positive tumors spread to the parametrial and pelvic lymph nodes significantly more often than did HPV-16-negative tumors (P less than 0.05). Demonstration of HPV-16 DNA in invasive cervical cancers may be an additional prognostic factor for this disease.  相似文献   
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Abstract: For the women with early-stage breast cancer who are candidates for breast conservation therapy, re-excision of the primary tumor bed has commonly been used in patients for several indications. These indications include positive margin or uncertain margin status of the primary excision or residual microcalcifications on postbiopsy mammogram. If the pathology from the re-excision does not confirm negative margin status, mastectomy is generally recommended. This article examines patients who have undergone a second re-excision (i.e., a lumpectomy followed by two re-excisions) who have been treated with breast conservation therapy rather than a mastectomy.
From September 1977 to November 1995, 1,562 patients underwent breast conserving therapy at this institution. Seven hundred forty of these patients underwent a re-excisional biopsy because of positive or uncertain margin status or residual microcalcifications after the first excision. Four patients (0.5%) underwent a second re-excision because of positive or uncertain margin status or residual microcalcifications on mammogram after the first re-excision. The final margin status after the second re-excision of all four patients was negative. The radiation dose was 4,600–5,000 cGy to the whole breast followed by a conedown to bring the total dose to 6,400–6,800 cGy to the primary tumor bed.
Follow-up in the four patients was 13 years, 4 years, 14 months, and 8 months respectively. All four patients are clinically without disease and have not had a locoregional recurrence. Cosmesis was excellent in all four patients. One patient had an adriamycin-induced recall reaction causing a cellulitis, which resolved with antibiotics. There were no other complications.
Highly selected patients may undergo breast-conserving therapy after a second re-excision. Good outcome and cosmesis can be achieved for this small subset of patients with avoidance of a mastectomy.  相似文献   
25.
In a 5-years' study, we investigated the correlation between clinical and histological diagnoses of blue nevi. In 24.7% of the cases, the clinical diagnosis turned out to be false; blue nevus was mostly confused with nevomelanocytic nevus (11.2%). Malignant melanoma was the primary differential diagnosis in 13 out of 89 cases. Differentiation of the histological subtypes identified 76.4% of the tumors as common blue nevi and 15.7% as cellular blue nevi. The remaining 7.9% were combined nevi. The average age of the patients with blue nevi at the time of excision was lower than that of the patients suffering from malignant melanoma during the same observation period. Comparison of the distribution of 89 blue nevi with 196 malignant melanomas revealed the different preferred areas of these tumors. We briefly refer to related dermal melanocytoses, such as Mongolian spot and Ota's nevus.  相似文献   
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Coaching provides nurse administrators with a framework for developing their management team. Middle managers who have been coached can use coaching to provide performance feedback and encourage teamwork within their staff. Coaching as a management strategy should be valued and practiced from the nurse executive on down through the organization.  相似文献   
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Zusammenfassung Nach Verifikation der anatomischen Voraussetzungen wurde eine modifizierte Technik des erweiterten saphenofasziokutanen Suralislappen für große kombinierte Knochen-Weichteil-Infekt-Defekt-Situationen sogenannte Typ-C-Läsionen bei Risikopatienten mit ersatzschwachem bzw. ersatzunfähigem Lager (traumatische ipsilaterale arterielle Hauptgefäßläsion, tiefe ipsilaterale Venenthrombose, diabetische Polyneuropathie mit Mikroangiopathie bzw. PAVK Stadium 3) in einer prospektiven Studie angewendet. Zehn Weichteildefekte zwischen 80–180 cm2 im Mittel-Rückfuß- bzw. distalen Unterschenkelbereich wurden einzeitig komplett mit einem retrograd gestielten modifizierten saphenofasziokutanen Suralislappen aus dem proximalen Unterschenkel gedeckt. Alle Lappen heilten ohne Lappennekrosen ein. Die Entnahmestellen wurden siebenmal mittels primärer Naht und dreimal einzeitig mit Meshgraft verschlossen. Bei der Nachuntersuchung aller Patienten nach im Mittel 22 Monaten bestanden vitale Lappen, keine Hebedefektmorbidität, kein Suralisneurom und es war kein sekundäres Debulking oder andere lappeninduzierte Revisionen erforderlich.  相似文献   
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