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961.
A total of 224 patients living in Lusaka, the capital city of Zambia, were treated for malaria in the University Teaching Hospital (UTH) and surveyed to determine the relationship between parasitaemia, malaria antibodies and travel outside Lusaka. Comparisons of those with parasitaemia or antibodies with those without suggested an increased risk among those who travelled out of Lusaka to high transmission areas and also among those who live in areas of Lusaka where transmission is considered to be high. This study shows that even if there is transmission of malaria in Lusaka, much of the malaria is contracted outside the city. Specificity and positive predictive values for the variables considered showed that these variables may be useful in a clinical situation in determining whether the patient has malaria or not. It is also suggested that these variables should be taken into consideration in assessing possibilities of malaria transmission in towns where control measures were once applied. 相似文献
962.
963.
964.
G F Watts W Ahmed J Quiney R Houlston P Jackson C Iles B Lewis 《British medical journal (Clinical research ed.)》1988,296(6617):235-237
The plasma lipid and lipoprotein responses to two modified isoenergetic diets including meat were studied in 15 free living men with hyperlipidaemia (mean plasma cholesterol and triglyceride concentrations 8.1 and 3.4 mmol/l). A reference diet (diet A, 42% energy from fat, ratio of polyunsaturated to saturated fatty acids (P:S ratio) 0.2) was compared with a fat reduced diet (diet B, 35% energy from fat, P:S ratio 0.5) and with a further fat modified diet supplemented with fibre (diet C, 27% energy from fat, P:S ratio 1.0). Daily intake of meat and meat products (180 g/day) was the same in each dietary period; that in diet A had a fat content typical of the average British diet, whereas that in diets B and C was based on very lean meat and meat products. During consumption of diet B the plasma cholesterol concentration fell by 8.6% and low density lipoprotein cholesterol by 11%. During consumption of diet C plasma cholesterol fell by 18.5% and low density lipoprotein cholesterol by 23.8%. Triglyceride and high density lipoprotein cholesterol concentrations and body weight did not change appreciably during the study. A modified diet including a moderate amount of lean meat and meat products is compatible with a reduced lipoprotein mediated risk of atherosclerotic heart disease. 相似文献
965.
Extensor tendon injuries of the hand are often inadequately managed. Poor outcomes include extensor lag, reduced range of flexion and weakened grip strength. Poor outcomes are particularly associated with injuries in zones 2–4, with severe crush and tissue damage, and in the presence of associated injuries. Dynamic splintage and controlled active mobilisation have some benefits over static splinting for zone 5–8 injuries but require closer supervision. 相似文献
966.
A visible light-cured composite resin (Brilliant DI) has been studied over a wide range of temperature and frequency by a dynamic mechanical flexural method. The derived data of logarithmic modulus and loss tangent (tan delta) show considerable changes following a secondary-cure process applied to the material. This involved the application of heat and intense light with temperatures rising to 120 degrees C in 7 min. Following this oven-cure the resin phase exhibited enhanced stiffness with the activation-energy barrier for molecular motion at the glass-transition rising from 220 to 291 kJ/mol. This study clarifies the nature and extent of the internal molecular changes which may be produced in the fabrication of a composite inlay. 相似文献
967.
Denis Lambrigts Pascale Van Calster Yuanxin Xu Michel Awwad Francisca A. Neethling Tomasz Kozlowski Alicia Foley Alan Watts Sanders J. Chae Jay Fishman Aron D. Thall Mary E. White-Scharf David H. Sachs David K.C. Cooper 《Xenotransplantation》1998,5(4):274-283
Abstract: The aim of this study was to deplete baboons of anti-αgalactosyl (αGal] antibody and attempt to maintain depletion by pharmacologic immunosuppressive therapy (PI). In 12 experiments, involving nine baboons, repeated extracorporeal immunoadsorption (EIA) was carried out by plasma perfusion through immunoaffinity columns of synthetic αGal trisaccharide type 6. Five of the baboons were immunologically naive and four had undergone various procedures at least 6 months previously. All, however, had recovered lymphohematopoietic function and (with one exception) had levels of anti-αGal antibody within the normal range. Eleven protocols included continuous i.v. cyclosporine (to maintain whole blood levels of approximately 1,600 ng/ml). In addition, in ten protocols, the baboon received one or more of the following drugs: cyclophosphamide (1–20 mg/kg/day), mycophenolate mofetil (70–700 mg/kg/day), brequinar sodium (1–12 mg/kg/day), prednisolone (1 mg/kg/day), melphalan (0.15–0.6 mg/kg/day), methylprednisolone (125 mg/day ×3), and antilymphocyte globulin (ATG) (50 mg/kg/day ×3). EIA was carried out on 1–9 occasions in each study and was temporarily successful in removing all antibody. When no PI was administered, antibody returned close to pre-EIA levels within 48 hr. Cyclosporine alone delayed the rate of antibody return only slightly. While EIA was continuing on a daily or alternate day schedule, antibody levels (both IgM and IgG) were maintained at 20–45% of pre-EIA levels. Once EIA was discontinued but PI maintained, IgM rose to 40–90% and IgG to 30–60% of pre-EIA levels. In vitro testing demonstrated significant cytotoxicity to pig cells at these antibody levels. We conclude that i) EIA utilizing columns of αGal trisaccharide is successful in temporarily depleting baboons of anti-αGal antibody, but ii) none of the PI regimens tested suppressed antibody production to levels which would be expected to prevent antibody-mediated rejection of pig xenografts. Additional strategies will therefore be required if xenotransplantation is to become a clinical reality. 相似文献
968.
M E Watts M F Dennis M R Stratford P Wardman 《International journal of radiation oncology, biology, physics》1986,12(7):1135-1138
The "extra" radiosensitization seen with GSH-reactive nitro compounds is too large to be accounted for by GSH-depletion acting independently--there must be competition. The GS-conjugate leaks out of cells slowly and is trapped at high concentrations. Its properties, such as concentration trapped and reduction potential, must be considered. Limited therapeutic exploitation of the glutathione conjugate trapping and concomitant GSH depletion may be possible if intratumor injection is permitted. 相似文献
969.
Elastic properties of muscles measured at the elbow in man: I. Normal controls. 总被引:1,自引:1,他引:0
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Passive elastic stiffness of muscle acting at the elbow was assessed in 19 normal subjects by measuring displacements produced by a torque motor acting at the joint. Stiffness ranged from 0.40 to 1.8 Nm/radian and was strongly correlated (r = 0.85) with upper arm volume, allowing us to define a "normal" range for stiffness when corrected for arm volume. In addition, the angle of the elbow with the arm fully relaxed and no external torque applied ("neutral" angle) was found to be 107 degrees +/- 10 degrees. Thus, we have quantified resting stiffness or "tone" in the arm and provided normal data for comparison with patients with pathophysiological conditions such as rigidity or spasticity. 相似文献
970.
Hunter R Watts JM Dunstan R Elmslie R O' Brien P Slavotinek A Walsh J 《Obesity surgery》1992,2(3):245-252
As part of the Adelaide Obesity Surgery Study, we have reviewed all patients who have undergone revisional surgery. Of the
310 trial patients, 63 (20%) had revisions 1-69 (median 32) months following their original surgery--30% of all 105 gastrogastrostomy
(GG) operations, 22% of 106 gastroplasty (GP) procedures, and 9% of 99 gastric bypasses (GB). Failure was due to stomal dilatation,
11% of all trial patients (71% of GG revisions), stomal stenosis, 6% (52% of GP revisions) and staple dehiscence, 4%. There
was no mortality and a low hospital morbidity. Long-term success was only 23% (follow-up at least 3 years) and was achieved
at considerable expense (3 reversals, 10 further revisions, 44 endoscopic procedures). Revisional surgery was successful in
45% of patients with stomal dilatation or dehiscence but in only 17% with stenosis. Overall, the most successful operation
was revision of, or conversion to, gastric bypass (58% success rate), compared with gastroplasty (24%) and gastrogastrostomy
(25%). Our long-term results following revisional surgery were disappointing, particularly for stenosis, and most failures
followed revision to GG or GP. Roux-en-Y gastric bypass is the procedure of choice when considering revision. 相似文献