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31.
32.
The human acute promyelocytic leukemia cell line HL-60 is induced by retinoic acid (RA) and N,N-dimethylformamide (DMF) to differentiate into cells having many of the functional and morphologic characteristics of mature granulocytes. With normal human phagocytic cells there is both superoxide anion (O2-) production and chemotaxis in response to chemoattractants such as N-formyl-methionyl-leucyl- phenylalanine (FMLP). We have now found that although HL-60 cells induced with RA alone produce O2- in response to 12-0-tetradecanoyl- phorbol-13-acetate (TPA) they are deficient in FMLP-stimulated O2- production and chemotaxis. In contrast, HL-60 induced either with DMF or with a combination of 10 nmol/L RA and a T cell-derived lymphokine, differentiation-inducing activity (DIA), produce O2- and exhibit chemotaxis in response to FMLP. The basis for these results appears to be the concentration of cell surface chemotactic peptide receptors. Thus, untreated HL-60 and HL-60 induced with either RA alone or DIA alone do not have measurable levels of FMLP receptors, whereas HL-60 induced with a combination of RA and DIA has 5,400 receptors per cell. HL-60 induced with RA and DIA plus 1 mumol/L dexamethasone have 25,000 receptors per cell and have greater chemotactic activity than HL-60 induced with the combination of RA and DIA. Thus, differentiation of HL- 60 to cells with many properties of normal phagocytes can be induced in vitro by physiologic substances. 相似文献
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Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
37.
Broca's area is a major neuroanatomical substrate for spoken language and various musically relevant abilities, including visuospatial and audiospatial localization. Sight reading is a musician-specific visuospatial analysis task, and spatial ability is known to be amenable to training effects. Musicians have been reported to perform significantly better than nonmusicians on spatial ability tests, which is supported by our findings with the Benton judgement of line orientation (JOL) test (P < 0.001). We hypothesised that use-dependent adaptation would lead to increased gray matter density in Broca's area in musicians. Voxel-based morphometry (VBM) and stereological analyses were applied to high-resolution 3D MR images in male orchestral musicians (n = 26) and sex, handedness, and IQ-matched nonmusicians (n = 26). The wide age range (26 to 66 years) of volunteers permitted a secondary analysis of age-related effects. VBM with small volume correction (SVC) revealed a significant (P = 0.002) region of increased gray matter in Broca's area in the left inferior frontal gyrus in musicians. We observed significant age-related volume reductions in cerebral hemispheres, dorsolateral prefrontal cortex subfields bilaterally and gray matter density in the left inferior frontal gyrus in controls but not musicians; a positive correlation between JOL test score and age in musicians but not controls; a positive correlation between years of playing and the volume of gray matter in a significant region identified by VBM in under-50-year-old musicians. We suggest that orchestral musical performance promotes use-dependent retention, and possibly expansion, of gray matter involving Broca's area and that this provides further support for shared neural substrates underpinning expressive output in music and language. 相似文献
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John D Murray Eric T Elwood Glyn E Jones Rebecca Barrick Jack Feng 《CANADIAN JOURNAL OF PLASTIC SURGERY》2009,17(1):17-21
BACKGROUND:
Risk factors for expander reconstruction infection are well known. However, drain use as a risk factor for the development of infection is unclear.OBJECTIVE:
To review a simple method for drain use to help reduce rates of infection in expander breast reconstruction.METHODS:
Two hundred consecutive single-surgeon (JDM) immediate first-stage expander breast reconstructions were retrospectively reviewed. The records were reviewed for history and physical examination, intra-operative technique, perioperative management, adjuvant therapy, and outcome with respect to expander infection necessitating premature explantation within the first eight weeks. Infection was defined on clinical basis, with or without culture positivity. All expanders (Mentor, USA) were the same model (textured, port-integrated and biodimensional). Two consecutive series of reconstructions were then created. The first series included 177 reconstructions while the second series included 23 reconstructions. Unlike the first series, the second series introduced a protocol in which all reconstructions received mupirocin 2% cream to the drain sites and all drains were removed at the end of the first week. Additionally, in the second series, all expanders were secluded from direct in vivo contact with the closed suction drain either by the use of an intervening Alloderm sling (LifeCell Corporation, USA, 15 of 23 breasts) or by subdermally tunnelling the drain superficial to an adequate fatty subcutaneous layer (eight of 23 breasts).RESULTS:
Patients who developed infection in the first series and all patients in the second series shared statistically the same level of aggregate risk factors (P=0.531). The infection rate (5.65%, 10 infections in 177 breasts) in the first series was statistically greater than in the second series (0%, 0 in 23 breasts, P=0.001).CONCLUSIONS:
The present study found that percutaneous closed suction drains do serve as an increased risk for expander infection. However, early results indicate that in vivo protection of the expander with Alloderm or subdermal tunnelling, topical antibiotic ointment use and early drain removal may significantly reduce expander infection. 相似文献40.
Granulocyte colony-stimulating factor crosses the placenta and stimulates fetal rat granulopoiesis 总被引:4,自引:0,他引:4
We studied the effect of recombinant human granulocyte colony- stimulating factor (rhG-CSF) administration to pregnant rats upon fetal and neonatal myelopoiesis. Pregnant rats were treated with rhG-CSF twice daily for 2, 4, and 6 days before parturition. rhG-CSF crossed the placenta and reached peak fetal serum concentrations 4 hours after administration. Peak fetal serum levels were 1,000-fold lower than levels detected in the dam. Hematopoietic effects of rhG-CSF were assessed by cytologic analysis of the newborn blood, spleen, bone marrow, thymus, and liver. White blood cell counts were increased twofold to fourfold in newborns. This increase was due to circulating numbers of polymorphonuclear cells (PMN). rhG-CSF induced a myeloid hyperplasia in the newborn marrow consisting of immature and mature myeloid cells in the day-2 and day-4 treated pups. Bone marrow of pups treated for 6 days contained mostly hyper-segmented PMN with little or no increase in myeloid precursors. An increase in the number of postmitotic (PMN, bands, and metamyelocytes) and mitotic (promyeloblasts, myeloblasts, and metamyeloblasts) myeloid cells in the spleen of neonates was observed. No change was detected in splenic lymphocytes or monocytes. No effect of rhG-CSF was noted in the newborn liver or thymus. These results demonstrate that maternally administered rhG-CSF crosses the placenta and specifically induces bone marrow and spleen myelopoiesis in the fetus and neonate. The significant myelopoietic effects of rhG-CSF at low concentrations in the fetus suggest an exquisite degree of developmental sensitivity to this cytokine and may provide enhanced defense mechanisms to the neonate. 相似文献