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991.
992.
J Ma MJ Stampfer E Giovannucci C Artigas DJ Hunter C Fuchs WC Willett J Selhub CH Hennekens R Rozen 《Canadian Metallurgical Quarterly》1997,57(6):1098-1102
Glomangiosarcoma is a rare malignant variant of the glomus tumor (GT). It has been reported in different anatomical locations, with only 1 report of its localization to the hand, despite the fact that its benign counterpart is most frequently found there. There is only 1 report of glomangiosarcoma that has metastasized. Special attention should be paid to GTs that are not well circumscribed, since the possibility of persistence and malignant transformation is increased in these lesions. The treatment of choice for glomangiosarcomas is wide local excision. 相似文献
993.
Kinetic studies of the inhibitory effects of propeptides subtilisin BPN' and Carlsberg to bacterial serine proteases 总被引:1,自引:0,他引:1
Huang HW; Chen WC; Wu CY; Yu HC; Lin WY; Chen ST; Wang KT 《Protein engineering, design & selection : PEDS》1997,10(10):1227-1233
The propeptides of bacterial subtilisin BPN' and Carlsberg were synthesized
to investigate their inhibitory function on the enzymes. Kinetically,
pro-BPN' inhibits the proteolytic activities of subtilisin BPN' and
Carlsberg separately in a slow binding mode. Pro-Carlsberg behaves as a
typical rapid equilibrium competitive inhibitor for these two proteases.
Functionally, pro-Carlsberg inhibits the subtilisins with moderate
selectivity. The inhibition constant Ki of pro-BPN' to subtilisin BPN' is
5.0 nM, and 6.1 nM to subtilisin Carlsberg. The on- rate of pro-BPN' to
subtilisin BPN' is 5.8 x 10(5) M(-1)s(-1), and the off-rate 2.9 x 10(-3)
s(-1). Similarly, the on-rate of pro-BPN' to subtilisin Carlsberg is 2.2 x
10(5) M(-1)s(-1), and the off-rate 1.3 x 10(-3) s(-1). On the other hand,
the Ki of pro-Carlsberg to subtilisin BPN' gives 1.3 x 10(2) nM, and 88 nM
to subtilisin Carlsberg. Based on the key features of the interactions
between pro-BPN' and subtilisin from X-ray crystallographic results
(Gallagher et al., 1995), the correlation between the sequence of
subtilisin propeptides and their inhibition abilities on the proteases are
compared and discussed.
相似文献
994.
WC Overweg-Plandsoen RG Weersink JH Sillevis Smitt P Fleury CJ van Asperen 《Canadian Metallurgical Quarterly》1997,141(13):624-629
OBJECTIVE: To analyse symptoms and complications in patients with neurofibromatosis type 1 (NF1). All patients were examined in a multidisciplinary outpatient neurofibromatosis clinic during a period of 10 years. DESIGN: Retrospective. SETTING: Academic Medical Center, University Hospital Amsterdam, the Netherlands. METHOD: All data on 450 persons visiting the neurofibromatosis clinic were stored in a database. Data were collected on the results of dermatological, neurological, ophthalmological and general examinations and on family history. For this study the follow-up data of 196 patients with a definite diagnosis of 'NF1' were analysed. RESULTS: In childhood diagnosis NF1 is predominantly based on specific dermatological symptoms such as > 6 café-au-lait (CAL) spots and freckling and on the presence of characteristic ophthalmological signs as two or more Lisch nodules. In this study the frequencies of these symptoms were 98% (CAL). 92% (freckles), and 93% (Lisch nodules) respectively. The frequencies of well-known complications of this disorder are comparable with the literature findings. In this study we found optic pathway glioma (OPG) in 10%, macrocephaly in 36%, hydrocephalus in 5%, retardation in 14%, brain tumours in 5%, kyphoscoliosis in 13%. renal artery stenosis in 0.5% and neurofibrosarcoma in 0.5% of NF1 patients. In children the degree of severity of this disorder is less than in adults, demonstrating the progressive character of the disease. CONCLUSION: The diagnosis of 'NF1' can usually be made by dermatological and ophthalmological examination. In case of a definite diagnosis in childhood regular follow-up is recommended since severe complications, such as OPG and kyphoscoliosis, may occur specifically in childhood and adolescence. For adult patients determination of the degree of severity is essential for the decision whether or not they need regular follow-up; they should have their blood pressure measured annually. 相似文献
995.
Insulin degradation: progress and potential 总被引:3,自引:0,他引:3
Insulin degradation is a regulated process that plays a role in controlling insulin action by removing and inactivating the hormone. Abnormalities in insulin clearance and degradation are present in various pathological conditions including type 2 diabetes and obesity and may be important in producing clinical problems. The uptake, processing, and degradation of insulin by cells is a complex process with multiple intracellular pathways. Most evidence supports IDE as the primary degradative mechanism, but other systems (PDI, lysosomes, and other enzymes) undoubtedly contribute to insulin metabolism. Recent studies support a multifunctional role for IDE, as an intracellular binding, regulatory, and degradative protein. IDE increases proteasome and steroid hormone receptor activity, and this activation is reversed by insulin. This raises the possibility of a direct intracellular interaction of insulin with IDE that could modulate protein and fat metabolism. The recent findings would place intracellular insulin-IDE interaction into the insulin signal transduction pathway for mediating the intermediate effects of insulin on fat and protein turnover. 相似文献
996.
997.
WC Petty 《Canadian Metallurgical Quarterly》1996,18(4):30-34
Operating tables evolved rapidly from 1860 through 1920. By 1920, the operating tables were well-designed for a wide variety of operations. Today, our operating tables resemble those developed in the early 20th century. 相似文献
998.
AM Kriska A Saremi RL Hanson PH Bennett S Kobes DE Williams WC Knowler 《Canadian Metallurgical Quarterly》2003,158(7):669-675
This study, examining the longitudinal relation among physical activity, body mass index, and development of type 2 diabetes in a high-risk population, is unique because diabetes was determined by oral glucose tolerance testing rather than by self-report. A physical activity questionnaire assessing past year leisure and occupational activity was administered to 1,728 nondiabetic Pima individuals aged 15-59 years as part of a series of clinic examinations in the Gila River Indian Community from 1987 to 2000. During an average follow-up period of 6 years, 346 subjects developed diabetes. Using time-dependent Cox proportional hazards modeling adjusting for age, the authors found that total activity was related to diabetes incidence in women and men (p < 0.05 in women only). After additional adjustment for body mass index, the relation between activity and diabetes incidence was weakened in both men and women. When the age-adjusted diabetes incidence rates were examined by levels of activity stratified by tertile of body mass index, the diabetes incidence rate remained lower in more active than in less active men and women from all body mass index groups, with the exception of the middle body mass index tertile in men (p < 0.05 in women only). These results suggest that the adoption and maintenance of a physically active lifestyle can play a significant role in preventing type 2 diabetes. 相似文献
999.
AL Cheng KH Yeh WC Uen RL Hung MY Liu CH Wang 《Canadian Metallurgical Quarterly》1998,82(10):1946-1951
BACKGROUND: Anecdotal reports have suggested that systemic chemotherapy with agents that better cross the blood-brain barrier may result in long term disease remission in some patients with central nervous system (CNS) lymphoma. This treatment strategy has the advantage of sparing patients the late neurologic complications from brain irradiation. METHODS: Eligible patients were required to 1) have tissue-proven and measurable non-acquired immunodeficiency syndrome (AIDS)- related primary or metastatic CNS lymphoma; 2) have normal hemogram, renal function, and hepatic function; 3) be age < or = 75 years; and 4) have provided informed consent. Patients with lymphoblastic lymphoma or patients who previously had been exposed to nitrosoureas, etoposide, or high dose methotrexate were not eligible. The systemic chemotherapy (BOMES regimen) included carmustine, 65 mg/m2/day, intravenously (i.v.) on Days 1-2; vincristine, 2 mg/day, i.v. on Days 1 and 8; methotrexate, 1.5 g/m2, i.v. on day 15 followed by leucovorin rescue; etoposide, 50 mg/m2/day, i.v. on Days 1-5; and methylprednisolone, 200 mg/day, i.v. on Days 1-7; repeated every 4 weeks (BOMES regimen). Four doses of intrathecal methotrexate were given to patients who had involvement in the cerebrospinal fluid. RESULTS: Between March 1991 and March 1997 a total of 19 patients were enrolled on the study. There were 13 men and 6 women, with a median age of 57 years. Fourteen patients had primary CNS lymphoma and 5 patients had concurrent extra-CNS lymphoma. Nine patients previously had been treated by radiotherapy (four patients), chemotherapy (three patients), or both (two patients). There were 11 complete remissions (CR) (57.9%) and 5 partial remissions (26.3%), with a total remission rate of 84.2%. One patient had had progressive brain lymphoma during systemic chemotherapy with the conventional cyclophosphamide, doxorubicin, vincristine, and prednisolone regimen, but achieved CR soon after the regimen was changed to BOMES. The median time to progression of the responders was 6 months. At last follow-up, 4 patients were alive without lymphoma at 10, 47, 64, and 66 months, respectively. There were two treatment-related deaths due to sepsis. Another two patients died of fulminant hepatitis that most likely was chemotherapy-related reactivation of chronic B viral hepatitis. CONCLUSIONS: The authors believe systemic chemotherapy alone may result in long term disease remission in some select patients with non-AIDS-related CNS lymphoma. Further investigation for better protocols is mandatory. 相似文献
1000.
WC Lee C Zhong S Qian Y Wan J Gauldie Z Mi PD Robbins AW Thomson L Lu 《Canadian Metallurgical Quarterly》1998,66(12):1810-1817
BACKGROUND: Administration of donor bone marrow (BM)-derived dendritic cell (DC) progenitors (DCp) that are major histocompatibility complex (MHC) class II+ but costimulatory molecule (CD40, CD80, CD86)-deficient can prolong mouse heart allograft survival This is associated with microchimerism and inhibition of antidonor cytotoxic T lymphocyte (CTL) activity. Genetic modification of these donor antigen-presenting cells to express an immunosuppressive molecule(s) may enhance their in vivo survival and potential tolerogenicity. METHODS: The surface phenotype of B10(H-2b) DCp before and after gene transfer using replication-deficient adenoviral (Ad) vectors was determined by monoclonal antibody (mAb) staining and flow cytometry. Transforming growth factor-beta (TGF-beta) production was quantitated by enzyme-linked immunosorbent assay. Allostimulatory activity of the gene-transduced DCp was ascertained by mixed leukocyte reaction (MLR) and CTL induction. To assess their in vivo migratory activity and survival, the transduced cells were injected subcutaneously into one hind footpad of C3H (H-2k) mice. Tissues (draining popliteal lymph nodes [LN], spleens, and thymi) were removed 1, 2, 7, and 14 days later and stained for donor MHC class II using anti-LA(b) mAb in an immunohistochemical procedure. The mean number of IAb+ cells per unit area was determined. RESULTS: Transduction with a control Ad vector (Ad-LacZ) at 50 multiplicity of infection slightly increased CD40 and CD86 expression and up-regulated the poor allostimulatory activity of the DCp assessed by MLR and CTL responses. These effects on function were negated in Ad-TGF-beta1-transduced cells. After their injection into mouse footpads, the gene-transduced IAb+ cells were observed in maximal numbers in the popliteal LN at day 1 and in marginal zones and T-dependent areas of spleens (peak at day 7) but were rare in thymi. Transduction with Ad-LacZ reduced the numbers of IAb+ cells identified in both LN and spleens at all time points postinjection, suggesting that the vector alone affected DC life span in allogeneic recipients. TGF-beta1 transgene expression not only fully prevented the reduction in DC induced by Ad transduction alone, but also increased numbers and prolonged the survival of donor cells in the spleen, as shown by a two-to fivefold increase in IAb+ cells at days 2-14 compared with control (Ad-LacZ-transduced) DC. CONCLUSION: BM-derived DCp can be transduced efficiently to express TGF-beta1 using an Ad vector. They exhibit very poor allostimulatory activity and similar migration characteristics in vivo to unmodified DCp. Survival of TGF-beta gene-transduced DC, however, is enhanced significantly compared with unmodified and (especially) control Ad-LacZ gene-transduced DC. Genetic engineering of donor DC to express the immunosuppressive molecule TGF-beta promotes their survival in allogeneic hosts and may potentiate their previously reported tolerogenicity. 相似文献