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71.
Efficient gene delivery to multipotential hematopoietic stem cells would greatly facilitate the development of effective gene therapy for certain hematopoietic disorders. We have recently described a rapid multiparameter sorting procedure for significantly enriching stem cells with competitive long-term lymphomyeloid repopulating ability (CRU) from 5-fluorouracil (5-FU)-treated mouse bone marrow. The sorted cells have now been tested as targets for retrovirus-mediated delivery of a marker gene, NeoR. They were cocultured for 4 days with fibroblasts producing a high titer of retrovirus in medium containing combinations of the hematopoietic growth factors interleukin-3 (IL-3), IL-6, c-kit ligand (KL), and leukemia inhibitory factor (LIF) and then injected into lethally irradiated recipients, together with sufficient "compromised" bone marrow cells to provide short-term support. Over 80% of the transplanted mice displayed high levels (> or = 20%) of donor- derived leukocytes when analyzed 4 to 6 months later. Proviral DNA was detected in 87% of these animals and, in half of them, the majority of the hematopoietic cells were marked. Thus, infection of the stem cells was most effective. The tissue and cellular distribution of greater than 100 unique clones in 55 mice showed that most sorted stem cells had lymphoid as well as myeloid repopulating potential. Secondary transplantation provided strong evidence for infection of very primitive stem cells because, in several instances, different secondary recipients displayed in their marrow, spleen, thymus and day 14 spleen colony-forming cells the same proviral integration pattern as the primary recipient. Neither primary engraftment nor marking efficiency varied for stem cells cultured in IL-3 + IL-6, IL-3 + IL-6 + KL, IL-3 + IL-6 + LIF, or all four factors, but those cultured in IL-3 + IL-6 + LIF appeared to have lower secondary engraftment potential. Provirus expression was detected in 72% of the strongly marked mice, albeit often at low levels. Highly efficient retroviral marking of purified lymphomyeloid repopulating stem cells should enhance studies of stem cell biology and facilitate analysis of genes controlling hematopoietic differentiation and transformation. 相似文献
72.
Soubhagya R. Nayak Ashwin Krishnamurthy SJ Madhan Kumar Latha V. Prabhu Bhagath Kumar Potu Sujatha D’Costa Anu Vinod Ranade 《Hand (New York, N.Y.)》2010,5(1):31-36
The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA)
can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar
artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation
of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal
tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation
of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed
to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed
with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the
RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm.
The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered
as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found
in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will
add to the existing knowledge of the vascular anatomy of forearm and hand. 相似文献
73.
Summary The purpose of this study was to evaluate the occurrence of superficial flaws after machining and to identify fracture initiation and propagation in three‐unit heat‐treated machined fixed partial dentures (FPDs) substructures made of hot isostatic pressed (HIPed) yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) after loaded to fracture. Four three‐unit HIPed Y‐TZP‐based FPDs substructures were examined. To evaluate the occurrence of superficial flaws after machining, the surfaces were studied utilizing a fluorescent penetrant method. After static loading to fracture, characteristic fracture features on both mating halves of the fractured specimens were studied using a stereomicroscope and a scanning electron microscope. Grinding grooves were clearly visible on the surfaces of the machined FPDs substructures, but no other flaws could be seen with the fluorescent penetrant method. After loading to fracture, the characteristic fracture features of arrest lines, compression curl, fracture mirror, fracture origin, hackle and twist hackle were detected. These findings indicated that the decisive fracture was initiated at the gingival embrasure of the pontic in association with a grinding groove. Thus, in three‐unit heat‐treated machined HIPed Y‐TZP FPDs substructures, with the shape studied in this study, the gingival embrasure of the pontic seems to be a weak area providing a location for tensile stresses when they are occlusally loaded. In this area, fracture initiation may be located to a grinding groove. 相似文献
74.
K. Mejri O. Abida M. Kallel‐Sellami S. Haddouk L. Laadhar I.R. Zarraa M. Ben Ayed M. Zitouni M. Mokni H. Lahmar B. Fezaa H. Turki F. Tron H. Masmoudi S. Makni 《Journal of the European Academy of Dermatology and Venereology》2011,25(7):774-781
Background Pemphigus is a life‐threatening autoimmune blistering disease mediated by autoantibodies against adhesion molecule of the skin. Its concurrence with systemic and organ‐specific autoimmune disease was described in case reports. Objectives To evaluate the presence of a broad spectrum of organ‐specific and non‐organ‐specific autoantibodies other than anti‐desmoglein antibodies in pemphigus patients. Patients and methods Serum samples were obtained from 105 pemphigus foliaceus (PF) patients, 51 pemphigus vulgaris (PV) patients and 50 controls. Both indirect immunofluorescence assay and ELISA were used to assess the presence of autoantibodies related to connective tissue diseases, autoimmune hepatitis, vasculitis, rheumatoid arthritis, coeliac disease, diabetes and thyroiditis. Results Significant difference was observed between the three groups for anti‐thyroglobulin antibodies in the pemphigus foliaceus group (18% vs. 4%, P = 0.03). A significantly higher occurrence of IgM anti‐cardiolipin (P = 0.03), IgG anti‐reticulin (P = 0.01) and IgG anti‐gliadin antibodies (P = 0.008) were observed in the PV group. Cases with more than four autoantibodies were frequently positives for both anti‐desmoglein 1 and anti‐desmoglein 3. Conclusion Autoantibodies other than anti‐desmoglein antibodies are not rare in pemphigus patients. Clinical and serological follow‐up of pemphigus patients with positive autoantibodies are needed to clarify their impact in disease evolution. 相似文献
75.
R. Kallel S. Krichen Makni S. Ellouze S. Chaabouni I. Chtourou B. Ben Ayed A. Khanfir M. Guermazi T. Sallemi Boudawara 《Oncologie》2008,10(9):563-567
Juvenile granulosa cell tumor of the ovary is a rare neoplasm that makes up less than 5% of ovarian tumors in childhood and adolescence. The majority of they tumors are diagnosed in stage I (FIGO) with a favorable prognosis. The aim of this work was to describe the pathological, clinical and therapeutic features of this rare tumor of ovary. The authors describe a juvenile cell tumor expressed by an abdominal and genital syndrome occurring in 30 and 35-year-old two young females. The tumor was strictly localized in the ovary in one case; the second patient presented a bilateral ovarian tumor and peritoneal metastasis at the diagnosis. Clinical follow-up of the latter patient showed a recurrence with liver metastasis in spite of a radical surgical treatment followed by chemotherapy. The first patient has a favorable evolution with a follow-up of two years. Various prognostic factors of the juvenile granulosa cell tumor of the ovary are currently being evaluated. Surgery is the treatment for local disease. Patients with locally advanced, recurrent or metastatic tumors require chemotherapy, although the optimal regimen remains to be determined. 相似文献
76.
Obstructive uropathies are a frequent cause of child renal failure. The prenatal diagnosis of such abnomalities should lead to appropriate management. OBJECTIVE: To evaluate the interest of ultrasonographic prenatal diagnosis of urinary tract malformations. PATIENTS AND METHODS: Retrospective study of 10 cases of urinary tract malformations diagnosed in utero. The mean age of the patients was 34.9 years and the mean gestational age at the prenatal diagnosis was 28.2 weeks of amenorrhea. The abnormalities diagnosed were: 2 cases of ureteropelvic junction obstruction, 3 cases of posterior urethral valves and 5 cases of mild hydronephrosis. The fetal karyotype, realised in 8 cases, was normal. In one case the urinary abnormalities was part of a multiple malformation syndrome and led to the termination of the pregnancy. 7 cases had a post-natal follow-up: 5 had a surgical management and two new borns had transient pyelectasies. The prediction of postnatal renal function is made by ultrasonographic appearance of the kidney and the amniotic fluid. Although the analysis of fetal urine for the assessment of renal function leads to conflicting results, it seems that sodium and beta-2 microglobulin urinary rates provide useful informations. 相似文献
77.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
78.
Open-angle glaucoma is most frequent in diabetics. Its evolution seems to be most severe although an equilibrated tonometry under glaucoma treatment in literature. Aim of the study: comparison of evolution of glaucoma between diabetics and non diabetics. MATERIAL AND METHODS: A retrospective study of 72 glaucomatous patients diabetic and non diabetic was performed. A complete ophthalmologic examination with tonometry, funduscopy: sup disc measurement and automated perimetry was realised. Evolution was studied after chirurgical or medical treatment each four months with a mean follow up of 2 years. RESULTS: We observed that the evolution of Open-angle glaucoma in diabetics is significatively not different from non diabetics. CONCLUSION: Open-angle glaucoma evolution in diabetics is not more severe than general population. 相似文献
79.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics. 相似文献
80.