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41.
Total radical trapping antioxidant potential (TRAP) and exercise   总被引:1,自引:0,他引:1  
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   
42.
43.
Transmission of human herpesvirus 8 (HHV-8) may occur through various routes including breastfeeding and sexual intercourse. We attempted to detect HHV-8 infection in nine HIV-positive couples discordant for Kaposi's sarcoma who maintained a monogamous sexual relationship for at least one year. By quantitative real-time polymerase chain reaction and HHV-8 genotyping we provide strong evidence for the sexual transmission of HHV-8 in this unique cohort.  相似文献   
44.
The oxidative response of rat polymorphonuclear leukocytes stimulated by phorbol myristate acetate and N-formyl-methionyl-leucyl-phenylalanine was studied. Ferricytochrome reduction and peroxidase-catalyzed decrease of scopoletin fluorescence were used to monitor O-2 and H2O2 release in the extracellular medium. Oxygen consumption was also measured in some experiments. Decrease of chlortetracyclin fluorescence after stimulation of dye-loaded cells was used to study an early step of cell stimulation. Finally, a possible relationship between cell responses and the medium redox potential was explored. Three major conclusions were obtained: Ferricytochrome reduction is dependent on the total cytochrome concentration, and a simple mathematical model allows a tentative estimate of total superoxide anion production by stimulated cells. Increasing cell concentration results in a decrease of individual cell response, and this may be accounted for by a direct inhibition of cell-released hydrogen peroxide on the reactivity of leukocytes. Further, H2O2 may be shown to inhibit an early step of cell response. The solution redox potential does not influence cell reactivity, since it may be dramatically decreased without inhibiting cell response.  相似文献   
45.
Alkaline battery foreign bodies of the ear and nose   总被引:1,自引:0,他引:1  
Button batteries as foreign bodies are dangerous because of their ability to cause liquefaction necrosis on contact with moist tissue. We treated two patients with disk batteries in the ear and nose. Both patients had severe local reactions, necessitating prolonged treatment. Prompt identification and rapid removal of these foreign bodies is recommended.  相似文献   
46.
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   
47.
H Capo  M J Kupersmith  A Berenstein  I S Choi  G A Diamond 《Neurosurgery》1991,28(5):733-7; discussion 737-8
The inferolateral trunk (ILT) of the internal carotid artery (ICA) is a branch that arises inferiorly from the C4 segment of the cavernous ICA. It provides blood supply to the 3rd, 4th, and 6th cranial nerves, as well as to the gasserian ganglion. The ILT anastomoses to branches of the internal maxillary artery, providing collateral circulation between the external carotid artery and the ICA systems. Retinal and cerebral emboli can arise from the external carotid artery system and travel via the ILT to the ICA. Cranial nerve palsies may result after occlusion of the ILT. We present the cases of four patients who had iatrogenic neurological dysfunction subsequent to intravascular procedures that involved the ILT. These cases provide further clinical confirmation of the importance of this blood vessel. A 5th case involving iatrogenic occlusion of the ILT and no neurological deficit is also presented, demonstrating that the ILT is not the sole blood supply of the cranial nerves in the cavernous sinus.  相似文献   
48.
白花前胡中前胡香豆素D和前胡香豆素E的分离和鉴定   总被引:7,自引:0,他引:7  
从中药白花前胡(Peucedanum Praeruptorum Dunn)根中分到5个化合物,经理化常数、波谱数据及化学反应分别鉴定为前胡香豆素D(I),Pd-Ib(II),前胡香豆素E(III),nodakenetin(IV)和scopoletin(V)。其中化合物I和III为两个新化合物,与巳知化合物凯林内酯的化学沟通确定了其绝对构型,其化学结构分别为3'(S),4'(S)-二乙酰氧基-3',4'-二氢邪蒿内酯(I)和3'(R)-惕各酰氧基-4'-酮基-3',4'-二氢邪蒿内酯(III)。化合物IV和V为首次从该植物中分离得到。通过DEPT,1H-1HCOSY和13C-1HCOSY等实验归属了II的碳氢信号。  相似文献   
49.
Neuronal cells from cerebral hemispheres of 14-day-old rats were grown for 6 days in a serum-free, chemically defined medium. About 95-98 and 3% of these cells were neurofilament and acetylcholinesterase (AChE)-positive, respectively. The addition of basic fibroblast growth factor (bFGF) at three developmental stages, i.e. at 4 h, 2 and 4 days resulted in an increase (about 2-fold) of the number of AChE-positive neurons. The enzyme reaction was present in the cell body as well as in the fibers, which often ramified extensively under the influence of bFGF. Treatment with bFGF after the 2nd day of culture had no or only a low stimulatory effect. Our findings indicate that bFGF affects the development of AChE-containing neurons, i.e. cholinoceptive neurons from rat cerebrum.  相似文献   
50.

Background

Phaconit or ultra micro incision phacoemulsification cataract surgery involves phacoemulsification through a 0.9 millimetre sleeveless phaco tip and irrigating chopper followed by implantation of a rollable intraocular lens. The procedure leads to negligible astigmatism and faster visual recovery as compared to phacoemulsification with a foldable intraocular lens.

Methods

This prospective study analysed 80 cases of sub millimetre phaconit surgery with implantation of rollable intraocular lenses(IOL) in 40 cases and acrylic foldable IOL in the remaining 40 cases. Evaluation of efficacy and adaptability of procedure, equipment settings, operative constraints, postoperative complications, keratometric and topographic evaluation of induced astigmatism with visual outcome and patient''s rehabilitation were studied.

Results

The intraoperative complications were surge/ chamber collapse in 16 (20%), iris chaffing in one and corneal burns in two cases. All cases had an induced astigmatism of less than or equal to ± 0.25 D in four to six weeks after rollable IOL and ± 0.5 D to ± 0.75 D after acrylic IOL implantation. All patients had best-corrected visual acuity of 6/6 by third post operative day.

Conclusion

Phaconit with rollable IOL is a perfect blend of surgical skill, application of technology and ultra thin IOL.Key Words: Phaconit, Ultra micro phaco, Submillimetre incision, Rollable IOL implantation  相似文献   
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