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931.
OBJECTIVE: The pituitary hormone, prolactin, accelerates systemic lupus erythematosus in NZB/NZW F1 (B/W) mice. Our study evaluated disease activity in B/W females experiencing the physiologic hyperprolactinemia of mating, pregnancy, suckling, and pseudopregnancy. METHODS: Nonsuckling postpartum, suckling and pseudopregnant mice were compared to virgin females. Serum prolactin, anti-DNA antibodies (anti-DNA), gp70-anti-gp70 immune complexes, IgM, IgG, albuminuria, and renal function were monitored serially. RESULTS: Females that whelped 2 litters had apparent stimulation of anti-DNA; those that suckled their young had similar premature appearance of anti-DNA as well as delayed, but marked, hypergammaglobulinemia. Pseudopregnant mice, which characteristically secrete repeated surges of prolactin, had significant acceleration of multiple variables of disease activity. CONCLUSIONS: Pregnancy, parturition and suckling did not immediately accelerate lupus in B/W dams, and longevity was not affected in females that had borne litters. Pseudopregnancy was the most effective stimulator of variables of autoimmunity. 相似文献
932.
Successful graft incorporation requires that an appropriate match be made among the biologic activity of a bone graft, the condition of the perigraft environment, and the mechanical environment. The authors have studied, in a wide variety of animal models, the factors that affect the main components of bone graft incorporation: revascularization, new bone formation, and host-graft union. The principal determinant of the rate, pattern, and amount of revascularization is the presence or absence of a vascular pedicle. The nonvascularized bone graft is entirely dependent on the surrounding tissue for its revascularization, which results in a noticeable delay in vessel ingrowth. The principal determinant of the rate and amount of new bone formation on, in, or about a bone graft is the presence or absence of living, histocompatible, committed bone-forming cells. When living cells are not part of the graft at the time of implantation, the cells that form new bone are derived from host tissues, and new bone formation is delayed. The principal determinants of host-graft union are stability of the construct and contact between host bone and the graft. Factors that slow or inhibit all of these processes are reduction of the biologic activity of the graft by freezing or some other treatment, histocompatibility antigen disparities between donor and recipient, mechanical instability between the graft and the perigraft environment, and local and systemic interference with the biologic activity of the graft and surrounding tissue, for example, by irradiation or the administration of cisplatin. The task of the clinician who does a bone grafting procedure is to choose the right graft or combination of grafts for the biologic and mechanical environment into which the graft will be placed. 相似文献
933.
PURPOSE: To transfect human corneal endothelial cells with a plasmid vector coding for the SV40 large T antigen to extend the life of the cells in culture. METHODS: Human corneal endothelial cells were transfected with the SV40 large T antigen-coding plasmid pSV3neo using the electroporation method. Transfected and control cells were propagated in culture until senescence. Polymerase chain reaction and immunofluorescence were used to demonstrate messenger RNA and protein, respectively, for the Simian virus 40 large T antigen in the transfected cells. Polymerase chain reaction and hot blotting were used to demonstrate messenger RNA coding for several growth factors and receptors in transfected and control cells. RESULTS: The transfected cells continued to proliferate to 38 passages (more than 120 population doublings) in culture (control cells, 8 population doublings). Transfected cells, but not control cells, expressed messenger RNA coding for the Simian virus 40 large T antigen. Similarly, immunofluorescent staining with monoclonal antibodies demonstrated that the Simian virus 40 large T antigen protein was present in the nucleus of the transfected cells. Transfected cells were shown to produce messenger RNA coding for epidermal growth factor, epidermal growth factor receptor, basic fibroblast growth factor, fibroblast growth factor receptor-1, interleukin-1 alpha, the interleukin-1 receptor, transforming growth factor beta-1, and the glucocorticoid receptor. Qualitative expression of the messenger RNA coding for each of these modulators was similar in proliferating primary corneal endothelial cells and proliferating or confluent transfected corneal endothelial cells. CONCLUSIONS: In culture, the life of human corneal endothelial cells transfected with a plasmid vector coding for the Simian virus 40 large T antigen is extended. This study suggests that human corneal endothelial cells have the capacity for extensive proliferation, but the proliferation of untransfected cells is regulated through mechanisms that have not yet been characterized. 相似文献
934.
Y Ziv JM Church JR Oakley E McGannon TK Schroeder VF Fazio 《Canadian Metallurgical Quarterly》1996,83(11):1578-1580
Although the operation of choice for patients with familial adenomatous polyposis (FAP) is restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA), its place in the management of patients with FAP and cancer has not been defined. The authors have reviewed their experience with these patients to determine the safety of IPAA and its efficacy as a cancer operation. The records of 55 patients with FAP who had undergone IPAA were examined. Follow-up studies included an annual questionnaire and physical examination. Eight patients had FAP with coexisting colorectal cancer. Median age at diagnosis was 25 (range 13-46) years, and at operation 33 (range 22-36) years. Of the eight patients (four men), four had colonic cancer and four had rectal cancer. Synchronous colorectal carcinoma was found in two patients. Staging according to the tumor node metastasis classification showed that five patients had stage 1 tumour, two had stage 2 and one had stage 3. Tumours were well, moderately or poorly differentiated in one, five and two patients respectively. During a median follow-up of 56 (range 14-98) months, metastasis developed in the liver of one patient 66 months after surgery. Two patients suffered complications: one had small bowel obstruction and the other mucosal prolapse. Tubular adenomas were found in the pouch of two patients and in the anal transitional zone of one. Pouch function is good to excellent in all surviving patients. Restorative proctocolectomy for patients with FAP and coexisting colorectal cancer can be undertaken with a favourable prognosis and function. It is compatible with curative intent. 相似文献
935.
936.
We have isolated and determined DNA sequence for the 5'-flanking regions of three Arabidopsis thaliana polyubiquitin genes, UBQ3, UBQ10, and UBQ11. Comparison to cDNA sequences revealed the presence of an intron in the 5'-untranslated region at the same position immediately upstream of the initiator methionine codon in each of the three genes. An intron at this position is also present in two sunflower and two maize polyubiquitin genes. An intron is also found in the 5'-untranslated regions of several animal polyubiquitin genes, although the exact intron position is not conserved among them, and none are in the same position as those in the higher plant polyubiquitin genes. Chimeric genes containing the 5'-flanking regions of UBQ3, UBQ10, and UBQ11 in front of the coding regions for the reporter enzyme Escherichia coli beta-glucuronidase (GUS) were constructed. When introduced transiently into Arabidopsis leaves via microprojectile bombardment, all resulted in readily detectable levels of GUS activity that were quantitatively similar. The introns of UBQ3 and UBQ10 in the corresponding promoter fragments were removed by replacement with flanking cDNA sequences and chimeric genes constructed. These constructs resulted in 2.5- to 3-fold lower levels of marker enzyme activity after transient introduction into Arabidopsis leaves. The UBQ10 promoter without the 5' intron placed upstream of firefly luciferase (LUX) resulted in an average of 3-fold lower LUX activity than from an equivalent construct with the UBQ10 intron. A UBQ3 promoter cassette was constructed for the constitutive expression of open reading frames in dicot plants and it produced readily detectable levels of GUS activity in transient assays. 相似文献
937.
RW Bringel CP Souza SE Araújo FP Lopasso J Gama-Rodrigues HW Pinotti AA Laudanna 《Canadian Metallurgical Quarterly》1996,51(5):195-197
The squamous cell carcinoma of the pancreas is an uncommon form of pancreatic cancer, with a frequency in the range of 0.5-3.5%. A rare case of a primary squamous cell pancreatic carcinoma, with gastric invasion and upper digestive bleeding, requiring surgical control is reported. The surgical technique to treat the bleeding is also detailed. 相似文献
938.
PE Bosted A Lung L Andivahis LM Stuart J Alster RG Arnold CC Chang FS Dietrich W Dodge R Gearhart J Gomez KA Griffioen RS Hicks CE Hyde-Wright C Keppel SE Kuhn J Lichtenstadt RA Miskimen GA Peterson GG Petratos SE Rock S Rokni WK Sakumoto M Spengos K Swartz Z Szalata LH Tao 《Canadian Metallurgical Quarterly》1992,46(6):2505-2515
939.
940.