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91.
Summary Bone changes in sickle cell disease occur due to marrow hyperplasia, tissue ischaemia and infarction due to vaso-occlusion. Between 1982 and 1991 thirty four patients were treated in the Orthopaedic and Neurosurgery Departments of the Kind Fahd University Hospital, Al-Khobar, with spinal complications due to sickle cell disease. There were 21 males and 13 females aged between 4 and 28 years (mean 17.4 years). Structural changes in the vertebral bodies due to marrow hyperplasia occurred in 44% of the patients. Avascular necrosis leading to collapse of the vertebral bodies was seen in 9 (27%) patients. Infective spondylitis was the most serious complication seen in 8 (24%) patients; the majority needed anterolateral decompression and bone grafting. The spine is often affected in sickle cell disease and aggressive treatment with close follow-up is required to avoid disabling complications.
Résumé Les modifications osseuses survenant au cours de la drépanocytose sont la conséquence d'une hyperplasie médullaire, d'une ischémie tissulaire et d'un infarcissement liés à l'occlusion vasculaire. Cette étude rétrospective analyse les complications rachidiennes de la drépanocytose observées de 1982 à 1991. Trente-quatre patients ont été traités dans les services d'orthopédie et de neuro-chirurgie de l'Hôpital universitaire King Fahd à Al Khobar. Il s'agissait de 21 hommes et de 13 femmes, âes en moyenne de 17.4 ans, avec des extrêmes de 4 à 28 ans. Des modifications structurales du corps vertébral liées à l'hyperplasie médullaire sont survenues chez 44% des patients. Des nécroses avasculaires responsables d'un effondrement du corps vertébral ont été observéees chez 9 patients (26.5%). La spondylite infectieuse, qui constitue la complication la plus grave, a concerné 8 patients (23.5%), dont la plupart ont bénéficié d'une décompression antérolatérale et de greffes osseuses. Nous pensons que le rachis est souvent atteint au cours de la drépanocytose et qu'un traitement agressif et une étroite surveillance sont nécessaires pour éviter des séquelles majeures.相似文献
92.
Dynamic assessment of the electrocardiographic QT interval during citrate infusion in healthy volunteers. 总被引:1,自引:0,他引:1 下载免费PDF全文
T. M. Davis B. Singh K. E. Choo J. Ibrahim J. L. Spencer A. St John 《Heart (British Cardiac Society)》1995,73(6):523-526
OBJECTIVE--To investigate changes in the electrocardiographic QT interval during rapidly induced, sustained hypocalcaemia in healthy volunteers. DESIGN--Serial rate corrected QT measurements were made during and after a variable rate trisodium citrate infusion designed to "clamp" the whole blood ionised calcium concentration 0.20 mmol/l below baseline for 120 min. SUBJECTS--12 healthy teetotallers aged 19- 36 years who were not receiving medication known to influence calcium homoeostasis. MAIN OUTCOME MEASURES--Whole blood ionised calcium concentration and QaTc intervals (onset of the Q wave to T wave apex divided by the square root of the RR interval). RESULTS--Mean (SD) ionised calcium concentration decreased from 1.18 (0.03) mmol/l preinfusion to values close to target (0.98 mmol/l) between 10 and 120 min. The QaTc interval lengthened from a baseline of 0.309 (0.021) to a maximum 0.343 (0.024) s0.5 at 10 min before returning to a stable level from 15 to 120 min (0.334 (0.023) and 0.330 (0.023) s0.5 respectively). The change from baseline of both variables expressed as a ratio (delta QaTc/ delta [Ca2+]) was greater during rapid induction of hypocalcaemia (at 5 and 10 min) than at other times during and after the infusion (P < 0.02). CONCLUSIONS--The disproportionate prolongation of QaTc interval during prompt induction of hypocalcaemia suggests rate dependency which can be represented by a hysteresis relation between (ionised calcium, QaTc) coordinates. This finding may have clinical implications. 相似文献
93.
Impact of diets with corn oil or olive/sunflower oils on DNA damage in healthy young men 总被引:2,自引:0,他引:2
BACKGROUND: Plant fats and oils are major sources of mono- and polyunsaturated fatty acids as well as vitamin E, the major fat-soluble antioxidants in human nutrition. Dietary antioxidants are expected to reduce cancer risk by minimizing DNA damage. AIM OF THE STUDY: To compare the effects of gamma-tocopherol rich corn oil and the mixture of the alpha-tocopherol rich olive/sunflower oil on plasma concentration of tocopherols and on the frequency of sister chromatid exchange (SCE), an indicator of DNA damage. METHODS: This study had a double-blind, cross-over design and was conducted in 20 normal healthy non-smoking males aged 19-31 years. Design included a 2-week adjustment period and two 2-week test periods in which diets containing 30% energy as fat including either 80 g of corn oil (CO) (20 mg alpha-tocopherol, 100 mg gamma-tocopherol) or 80 g of olive/ sunflower oil (OSO) (24 mg alpha-tocopherol, 2.4 mg gamma-tocopherol), as the main fat-source, were given. Blood samples for analysis of SCE rate and content of tocopherols were collected at the beginning (T0), after adjustment (T1) and after the test period (T2) in intervals of 2 weeks. RESULTS: After two weeks of the corn oil diet, the plasma concentration of gamma-tocopherol increased but alpha-tocopherol decreased significantly compared to the olive/sunflower oil diet. The concentration of alpha-tocopherol increased (CO: 22.99 +/- 1.11 vs. OSO: 24.40 +/- 1.49 micromol/l) and that of gamma-tocopherol decreased (CO: 4.19 +/- 0.29 vs. OSO: 2.99 +/- 0.25 micromol/l) after the olive/sunflower oil diet. Intake of the corn oil diet was associated with reduced SCE rate and intensity, whereas there was no change in SCE after the olive/sunflower oil diet (CO: 7.66 +/- 0.25 vs. OSO: 8.06 +/- 0.47 mean SCE/cell) CONCLUSIONS: The combination of gamma-tocopherol with alpha-tocopherol in corn oil diet despite the lower alpha-tocopherol equivalents/diene acid equivalents ratio achieved better protection against DNA damage than alpha-tocopherol alone in the olive/sunflower oil diet. 相似文献
94.
Imaging of septate gallbladder 总被引:1,自引:0,他引:1
95.
High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation
of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification
of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases
of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be
diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions
that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able
to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article
is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist.
Received: 10 September 1998 Accepted: 24 November 1998 相似文献
96.
RID=" ID=" <E5>Correspondence to:</E5> Y. Akgun, M.D. 相似文献
97.
Ibrahim IN Okabayashi T Ristiyanto Lestari EW Yanase T Muramatsu Y Ueno H Morita C 《European journal of epidemiology》1999,15(1):89-93
The prevalence of antibodies against spotted fever group rickettsia (SFGR), murine typhus and Q fever were investigated in wild rats captured in Indonesia. Sera of 327 rats were collected from Jakarta and Boyolali on Java Island. The prevalences of antibodies against SFGR and murine typhus were 128 (39.1%) and 48 (14.7%), respectively. Antibodies against Q fever were not detected in these serum samples. Antibodies against SFGR were found in all species of rats (20.8–51.9%). The antibody positive rate against murine typhus in Rattus norvegicus (38.0%) was significantly higher than that in other rat species (0–4.8%, p < 0.01). The antibody positive rates against SFGR and murine typhus in rats captured in Jakarta were significantly higher than those in rats captured in Boyolali (p < 0.01). In this survey, all species of rats had antibodies against SFGR, indicating that the 4 species of tested rats (R. norvegicus, R. rattus, R. exulans, R. tiomanicus) were infected with SFGR and that SFGR may infest the whole of Java Island. Most of the rats that were antibody-positive against murine typhus were captured in Jakarta. Therefore, R. norvegicus and R. rattus are likely to be important hosts of murine typhus in Jakarta. The antibody-positive rates against SFGR and murine typhus in rats captured in the dry season were significantly higher than those in rats captured in the rainy season. This may coincide with the active periods of ticks and fleas in Indonesia. 相似文献
98.
99.
M Mazzei E Sottofattori R Dondero M Ibrahim E Melloni M Michetti 《Il Farmaco; edizione pratica》1999,54(7):452-460
The ability of some N,N-dialkylaminosubstituted chromones and isoxazoles to inhibit the protein kinase C (PKC) dependent signal transduction pathway was tested. As a cellular model, human neutrophils stimulated with either phorbol myristate acetate (PMA) or formylmethionine-leucine-phenylalanine (f-MLF) were used. The efficiency of the compounds was established by their capacity to reduce the O2- production by activated human neutrophils. Compounds carrying a 3-bis(2-methoxyethyl)amino group, a substituent found active in previously tested tricyclic compounds, do not show significant anti-PKC activity in this study. On the other hand, substitution with a 1-piperidinyl group leads all tested compounds to a high biological activity against stimulated neutrophils. 相似文献
100.
Jack CI Cottier B Jackson MJ Cassapi L Fraser WD Hind CR 《International journal of radiation oncology, biology, physics》1996,34(1):149-154
PURPOSE: Radiation pneumonitis is thought to occur as the result of excess free radical generation following radiotherapy. Various in vitro studies have shown that large doses of irradiation can cause membrane lipid peroxidation and the oxidation of protein sulphuryl groups. We, therefore, studied two circulating markers of lipid peroxidation and an indicator of "catalytic iron" (potentially available iron to catalyze the generation of free radicals) in patients undergoing radiotherapy. METHODS AND MATERIALS: The 9,11 diene conjugate of 9,12 linoleic acid, expressed as their molar ratio (percentage molar ratio (MR)) and thiobarbituric acid reactive acid-substances (TBARS), as well as levels of circulating desferrioxamine-chelatable iron assay, were assayed. Serial blood samples were taken over a 3-month period in 25 patients with inoperable nonsmall cell lung cancer. RESULTS: Ten patients developed radiation pneumonitis. The patients who developed pneumonitis showed a tendency for the serum percentage molar ratio to increase after a week. The change in the percentage molar ratio between Time 0 and 1 week of radiotherapy was significantly higher in the group that subsequently developed pneumonitis compared to the group that did not (p = 0.002). The initial serum TBARS levels in patients were not significantly elevated compared to controls and there was no difference in the serum TBARS levels in the pneumonitis and nonpneumonitis groups throughout the study period. After 1 week of radiotherapy the group that subsequently developed pneumonitis had a significantly higher level of desferrioxamine-chelatable iron (DFx-iron) compared with the nonpneumonitis group (p = 0.05). CONCLUSION: These data suggest that both the percentage MR and DFx-iron appear to reflect an increased susceptibility to develop radiation pneumonitis and after 1 week of radiotherapy they indicate patients who are likely to subsequently develop pneumonitis. Hence, these indicators could indicate the group of patients that could benefit from intervention therapies with antioxidants. 相似文献