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71.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
72.
Patrícia De Souza Rossignoli Oduvaldo CM Pereira Agnaldo B Chies 《Clinical and experimental pharmacology & physiology》2010,37(3):368-374
1. Orchidectomy results in long‐term testosterone deprivation similar to that observed in male clinical pathologies, such as hypogonadism and age‐related reductions in plasma testosterone concentrations. Although the vascular effects of these sorts of hormone deprivations are known in arteries, they have not been studied to the same extent in veins. 2. The aim of the present study was to determine the effect of orchidectomy, with or without subsequent testosterone replacement (started 23 days after orchidectomy; 10 mg/kg, i.m., testosterone propionate once every 5 days for 3 weeks), on responses of rat isolated portal veins and vena cavae to exogenous phenylephrine (PE). Isolated vessels were mounted in an organ bath and concentration–response curves constructed to PE (10?10–10?4 mol/L), endothelin (ET; 10?10–10?5 mol/L) and KCl (10?2–1.2 × 10?1 mol/L; as a control). 3. Orchidectomy had no effect on contractile responses of either the portal vein or vena cava to KCl. However, orchidectomy enhanced the maximum response (Rmax) of the portal vein, but not the vena cava, to PE. Testosterone replacement had no effect on these responses. The effects of orchidectomy on the Rmax to PE in portal veins were not altered by the nitric oxide synthase inhibitor NG‐nitro‐l‐ arginine methyl ester (10?4 mol/L) alone or combined with 10?5 mol/L indomethacin (a non‐selective cyclo‐oxygenase inhibitor), but they were abolished following treatment of isolated vessels with the ETA and ETB receptor antagonists BQ‐123 and BQ‐788 (both at 10?6 mol/L). Orchidectomy did not alter portal vein responses to the application of exogenous ET. 4. The results of the present study indicate that orchidectomy‐induced decreases in plasma testosterone can increase the venoconstrictor effects of PE on the portal vein and that this effect involves activation of both ETA and ETB receptors by locally produced ET. 相似文献
73.
Stephen M. Ansell Anne J. Novak Steven Ziesmer Tammy Price‐Troska Betsy LaPlant Stacey R. Dillon Thomas E. Witzig 《American journal of hematology》2009,84(2):71-73
Serum B‐lymphocyte stimulator (BLyS) levels are elevated in a subset of non‐Hodgkin lymphoma (NHL) patients, particularly those with a family history of B‐cell malignancies or a polymorphism in the BLyS gene. BLyS promotes growth of malignant B‐cells and increased serum BLyS levels are associated with a poor clinical outcome. In this study, BLyS levels were measured before and after 4 weekly doses of rituximab in 30 patients with previously untreated follicular Grade 1 NHL. A significant increase was seen in the serum levels of BLyS (P = 0.0001) after rituximab therapy. The increase was independent of genetic variability in the BLyS gene. Am. J. Hematol., 2009. © 2008 Wiley‐Liss, Inc. 相似文献
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77.
Cleusa P Ferri Sandro S Mitsuhiro Marina CM Barros Elisa Chalem Ruth Guinsburg Vikram Patel Martin Prince Ronaldo Laranjeira 《BMC public health》2007,7(1):209
Background
Both violence and depression during pregnancy have been linked to adverse neonatal outcomes, particularly low birth weight. The aim of this study was to investigate the independent and interactive effects of these maternal exposures upon neonatal outcomes among pregnant adolescents in a disadvantaged population from Sao Paulo, Brazil. 相似文献78.
Savas M. Menticoglou MD CM Frank A. Manning MD Ian Morrison MB Chris R. Harman MD 《The Australian & New Zealand journal of obstetrics & gynaecology》1992,32(2):100-103
Because difficult vaginal delivery is more frequent with macrosomic fetuses, some writers recommend routine Caesarean section for the delivery of fetuses greater than or equal to 4,500 g. The purpose of this study was to evaluate the appropriateness of this recommendation. A retrospective review was undertaken to determine how many fetuses born in our hospital weighing greater than or equal to 4,500 g died or were permanently damaged as a consequence of mechanical difficulties at delivery. During a 10-year period, 590 (75%) of 786 cephalic babies weighing greater than or equal to 4,500 g and alive at the start of labour were born vaginally. No baby died or was permanently damaged as a consequence of mechanical difficulties at delivery. Routine Caesarean section for macrosomic fetuses to prevent death or damage from difficult delivery is not warranted by our results. 相似文献
79.
In a double blind study, 40 infants with cows' milk intolerance of various causes were randomised to receive a nutritionally complete formula in which nitrogen was supplied either as whey hydrolysate or amino acids. The median age of infants was 10 weeks (range 36 weeks' gestation to 108 weeks' postnatal age). After a median follow up period of 25 weeks there was no significant difference in dietary intake between the formulas. Twenty four weeks after entry, weight and weight for length improved equally on both formulas. Plasma albumin improved significantly on the hydrolysed whey formula but not in the amino acid group. Both milks were palatable and normal intakes of formula were maintained. Biochemical and haematological indices remained within normal limits. There was no difference in stool frequency and vomiting between the two formulas. Two infants developed a probable allergic colitis while receiving hydrolysed whey. Amino acid formula may have a role in the management of atopic infants with severe cows' milk intolerance who have already reacted to whey or casein hydrolysate formula. 相似文献
80.
The Significance of Mild Squamous Atypia on Cytology 总被引:2,自引:0,他引:2
J. E. Dew FRACOG P. Athanasatos B AppSc CT CM N. F. Hacker MD FRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1995,35(4):443-445
Summary: Between January, 1991 and February, 1993 inclusive, 396 Papanicolaou smears were reported to show Mild Squamous Atypia with or without Human Papilloma Virus (MSA ± HPV). All women with MSA ± HPV smears were routinely recalled for colposcopy. To determine the significance of MSA ± HPV on routine smear screening, the records of all patients were reviewed.
Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion.
It is concluded that all asymptomatic women with MSA ± HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months. 相似文献
Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion.
It is concluded that all asymptomatic women with MSA ± HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months. 相似文献