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71.
Storey PA Anemana S van Oostayen JA Polderman AM Magnussen P 《The British journal of radiology》2000,73(867):328-332
Human infection with Oesophagostomum bifurcum, a parasitic intestinal helminth, is endemic in parts of West Africa. Oesophagostomum bifurcum juveniles develop in the colonic wall, causing pus-filled granulomas. The pathology has two distinct forms. Multinodular oesophagostomiasis comprises hundreds of small nodules within a thickened, oedematous wall of the large intestine. Uninodular oesophagostomiasis, called the Dapaong tumour, presents as a painful 30-60 mm granulomatous mass in the abdominal wall or within the abdominal cavity. Diagnosis of oesophagostomiasis on clinical grounds alone is difficult. We describe cases illustrating the ultrasound appearance of these two presentations. Multinodular disease shows nodular "target" and "pseudokidney" colonic lesions. The Dapaong tumour is an echo-free ovoid lumen enveloped within a well defined poorly reflective wall. 相似文献
72.
E Storey R J Gardner M A Knight M L Kennerson R R Tuck S M Forrest G A Nicholson 《Neurology》2001,57(10):1913-1915
A kindred is described with a dominantly inherited "pure" cerebellar ataxia in which the currently known spinocerebellar ataxias have been excluded. In the eight subjects studied, a notable clinical feature is slow progression, with the three least affected having only a mild degree of gait ataxia after three or more decades of disease duration. Pending an actual chromosomal locus discovery, the name spinocerebellar ataxia (SCA)15 is expectantly applied. 相似文献
73.
GA McCarthy B Kampmann V Novelli RF Miller DE Mercey D Gibb 《Archives of disease in childhood》1996,74(5):455-457
AIDS related Kaposi's sarcoma is commonly seen in homosexual men, only occasionally in men and women with heterosexually acquired HIV, and extremely rarely in children. The case of an HIV infected mother and her vertically infected child who both developed visceral Kaposi's sarcoma is reported. It is proposed that the putative Kaposi's sarcoma agent may also be transmitted vertically. 相似文献
74.
Complications from radiotherapy dose escalation in prostate cancer: preliminary results of a randomized trial 总被引:4,自引:0,他引:4
Storey MR Pollack A Zagars G Smith L Antolak J Rosen I 《International journal of radiation oncology, biology, physics》2000,48(3):635-642
OBJECTIVE: To compare early and late side effects in prostate cancer patients with Stage T1b-T3 disease randomized to receive 70 Gy or 78 Gy. METHODS: There were 189 patients randomized with a minimum follow-up of 2 years, that were available for this analysis. All patients were initially treated with a 4-field box to an isocenter dose of 46 Gy at 2 Gy per fraction. In the 70-Gy arm, treatment was continued to a reduced volume using a 4-field box technique. In the 78-Gy arm, treatment was continued to a reduced volume using a conformal 6-field arrangement. Side effects were graded on a 1-4 scale, adapted from Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. RESULTS: No significant differences in acute rectal or bladder toxicity were seen between the two treatment techniques (p > 0.6 for all comparisons). The 5-year Kaplan-Meier risks of Grade 2 or higher late bladder toxicity were 20% and 9% for 70-Gy and 78-Gy groups, respectively (log rank, p = 0.8). The 5-year risks of Grade 2 or higher late rectal toxicity were 14% and 21% for 70 Gy and 78 Gy, respectively (p = 0.4). Dose-volume histogram analysis of the 78-Gy patients showed a significant correlation between the percentage of rectum irradiated to 70 Gy or greater and the likelihood of developing late rectal complications. Patients with more than 25% of the rectum receiving 70 Gy or greater had a 5-year risk of Grade 2 or higher complications of 37% compared to 13% for patients with 25% or less (p = 0.05). All three Grade 3 complications occurred when greater than 30% of the rectum received 70 Gy or more. CONCLUSION: The overall rate of complications was similar in both treatment arms. However, there is evidence for a significant increase in late rectal complications when more than 25% of the rectum received 70 Gy or greater. This parameter may serve as a benchmark for the design of future three-dimensional conformal trials. 相似文献
75.
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77.
The disadvantages to single-dose treatment of malaria are: 1) the drugs used are subject to local availability, 2) the dosages used differ from country to country, and 3) seldom have preliminary trials been carried out under local conditions to evaluate the drugs. The trial described in this paper was undertaken in a savanna area of northern Nigeria where malaria was hyperendemic, from March-May 1969. 522 subjects having plasmodium falciparum trophozoites in their blood were selected and divided into 4 groups, from a total of 3 villages, Tama, Koda, and Fakuwa. In groups 1, 2, and 3 the dosages of chloroquine base administered alone were adjusted to body weight, surface area of subject, and age; in group 4 a combination of chloroquine diphosphate and pyrimethamine was given at a standard dosage related to age. Blood films were taken daily from all subjects on days 1-5, every 5 days from day 5-30, and every 10 days until day 60. 425 subjects were retained throughout the trial. Findings were: 1) in all 4 groups the parasite rates declined to levels of 3.3-7% on day 3 and to only 1.3-3.4% of the original level by day 5, 2) the percentage of recrudescence among subjects with diarrhea (10.8%) at the time of medication is slightly higher than that among those without diarrhea (7.1%) and in the 14 and over age group recrudescence was less in group 1 (4.1%) than group 4 (9.7%), in which the adult dosage was limited to a standard 450 mg of chloroquine base, 3) of the 32 detected cases that became positive again between day 10-60, malaria parasites were found on only 1 occasion in 21 and twice in 2 of them, 4) the gametocyte rates increased in all groups but the rise in the 14 and over age group was less pronounced, 5) no side effects other than vomiting were reported (rate of between 2.5-8%), 6) a single-dose treatment with chloroquine in dosages of 10 mg of base/kg body weight or higher failed to prevent the reappearance of parasites within 2 months of treatment in 6.5-11% of children in the 1-9 year age group, 7) the 4 types of treatment with chloroquine proved to be equally effective in all age groups, and 8) dosages of chloroquine adjusted to body weight range would appear preferable and could be used by health professionals in mass drug administration studies. 相似文献
78.
Previous work suggests that bone mineral in rats discriminatesin vivo for Ca against Sr by a factor of about 1.61. Modification of this has been observed in biological and synthetic apatites containing Sr prepared under the following conditionsin vivo andin vitro: rats fed 2.5% SrCO3 for 3–4 months; incorporation of Sr into pre-formed bone powder, or hydroxyapatite by equilibrationin vitro and by heating Sr minerals to 350–500°. Discrimination in mineral formedin vitro is at first similar to thatin vivo, but as the amorphous precipitate crystallizes it becomes much greater. Sequential dissolution of mineral specimens in 0.1–0.01 N acid-ethanol solutions indicates that Sr incorporation is a surface phenomena in preformed minerals, but is more homogeneously distributed in mineral heated, or grownin vivo orin vitro. During equilibration in tris buffer, discrimination ranged from over 50 to 2.4. This decreased with (1) decrease in pH, (2) decrease in solid/solution ratio, and (3) increased homogeneity of Sr in mineral. Discrimination in serum was negligible. It is postulated that equilibrium in buffer solutions involves a reprecipitated surface phase of different Ca/Sr ratio from the body of the crystal, which could account for the apparent discrimination against Srin vitro.
Zusammenfassung Frühere Untersuchungen führen zur Annahme, daß das Verhältnis der Aufnahme von Calcium zu jenem von Strontium im Knochenmineral von Rattenin vivo ungefähr 1,61 ist. Diese Resultate veränderten sich, wenn biologische und synthetische, Sr enthaltende Apatite unter folgendenin vivo undin vitro Bedingungen hergestellt wurden: 1. Ratten, die während 3–4 Monaten mit 2,5% SrCO3 gefüttert wurden; 2. Einbau von Sr durch Equilibrationin vitro in vorgebildetes Knochenpulver oder Hydroxyapatit; 3. durch Erhitzen von Sr-Mineralien auf 350–500°C. Die Diskriminierung imin vitro gebildeten Mineral ist zuerst derjenigenin vivo ähnlich, aber sobald sich der amorphe Niederschlag kristallisiert, wird sie viel größer. Die stufenweise Auflösung der Mineralproben in 0,1–0,01 N Säure-Alkohollösungen deutet darauf hin, daß der Sr-Einbau ein Oberflächenphänomen vorgeformter Mineralien ist, daß er jedoch in erhitztem oderon vivo, oderin vitro gewachsenem Mineral homogener verteilt ist. Während der Equilibration mit Tris-puffer variierte die Diskriminierung von über 50 bis 2,4. Sie nahm ab durch 1. Abnahme des pH, 2. Abnahme des Verhältnisses feste Masse/Lösung, 3. Zunahme der Homogenität von Sr im Mineral. Die Diskriminierung im Serum war belanglos. Es wird postuliert, daß das Gleichgewicht in Pufferlösungen eine Oberflächenphase mit erneutem Niederschlag bewirkt, bei welcher das Ca/Sr-Verhältnis anders ist als im Inneren des Kristalls; dies könnte die scheinbare Diskriminierung gegen Srin vitro erklären.
Résumé D'après des travaux antérieurs, il semble que le minéral osseux, chez le Rat, effectue une discriminationin vivo du Sr de l'ordre de 1.61. Des modifications de ce fait ont pu être observées dans des apatites biologiques et synthétiques, contenant du Sr, préparées dans les conditionsin vivo etin vitro suivantes: chez des rats soumis à 2,5% de SrCO3, pendant 3–4 mois: incorporation de Sr dans de la poudre d'os ou de l'hydroxyapatite, par équilibre in vitro; par chauffage des minéraux contenant du Sr à 350–500°. La discrimination, en minéral, forméin vitro, est initialement identique à celle forméein vivo, mais, à fur et à mesure de la cristallisation du précipité amorphe, elle augmente nettement. Une dissolution progressive de specimens dans des solutions à 0.1–0.01 N acide-alcool, montre que l'incorporation du Sr est un phénomène de surface au niveau de minéraux préformés. Le Sr est réparti de façon plus homogène dans les minéraux chaffés, ou obtenus par croissancein vivo ouin vitro. Pendant la mise en équilibre dans un tampon «tris», la discrimination varie de 50 à 2,4. Elle décroit avec 1. la chute du pH, 2. la décroissance du rapport solide/solution et 3. l'augmentation de l'homogénéité du Sr dans le minéral. La discrimination dans le sérum est négligeable. Il semble que l'équilibre dans des solutions tampons fait intervenir une phase de surface reprécipitée, dont le rapport Ca/Sr est différent de celui du corps cristallin, et qui pourrait rendre compte de la discrimination apparente envers le Srin vitro.相似文献
79.
80.
Murray-Johnson L Witte K Boulay M Figueroa ME Storey D Tweedie I 《International quarterly of community health education》2005,25(1-2):185-207
Scholars within the fields of public health, health education, health promotion, and health communication look to specific theories to explain health behavior change. The purpose of this article is to critically compare four health theories and key variables within them with regard to behavior change in the area of reproductive health. Using cross-country analyses of Ghana, Nepal, and Nicaragua (data sets provided by the Center for Communication Programs, Johns Hopkins University), the authors looked at the Health Belief Model, Theory of Reasoned Action, Extended Parallel Process Model, and Social Cognitive Theory for these two defined objectives. Results show that all four theories provide an excellent fit to the data, but that certain variables within them may have particular value for understanding specific aspects of behavior change. Recommendations for the selection of theories to use as guidelines in the design and evaluation of reproductive health programs are provided. 相似文献