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951.
EC Svensson HB Black DL Dugger SK Tripathy E Goldwasser Z Hao L Chu JM Leiden 《Canadian Metallurgical Quarterly》1997,8(15):1797-1806
Erythropoietin (Epo)-responsive anemia is a debilitating complication of chronic renal failure and human immunodeficiency virus (HIV) infection that effects more than 150,000 Americans. Patients with Epo-responsive anemias are currently treated with repeated injections of recombinant human Epo. In the studies described in this report, we have examined the safety and efficacy of using a single intramuscular (i.m.) injection of replication-defective adenoviral vectors (RDAd) encoding Epo for the treatment of Epo-responsive anemias in both mice and non-human primates. Our results demonstrate that there is a threshold dose of virus (2.5-8 x 10(7) pfu/gram of body weight) which is required to obtain long-term Epo expression and polycythemia in both species. A single i.m. injection of mice with 10(9) pfu of an RDAd encoding murine Epo (AdmEpo) resulted in elevations in hematocrits from control values of 49 +/- 0.9% to treated values of 81 +/- 3%, which were stable for more than 1 year. Similarly, a single i.m. injection of a monkey with 4 x 10(11) pfu of an RDAd-encoding simian Epo (AdsEpo) resulted in elevations of hematocrits from control levels of 40% to treated levels of > or =70%, which were stable for 84 days. Intramuscular injection of monkeys with AdsEpo appeared to be safe in that we did not detect abnormalities in chest X-rays, serum chemistries, hematologic, or clotting profiles (apart from elevated hematocrits) or organ histologies during the 84-day time course of the experiment. Taken together, these results suggest the feasibility of using i.m. injection of RDAd for the treatment of Epo-responsive anemias in humans. 相似文献
952.
T lymphocytes bearing the gamma/delta T-cell receptor are a rare component of normal human GI epithelium and skin. Recently, however, an unusually high percentage of T lymphocytes with gamma/delta receptors has been described in gastrointestinal biopsies from patients with dermatitis herpetiformis, implicating the gamma/delta T cell subset in the pathogenesis of this disease. We investigated a possible role for this subset of lymphocytes in the pathogenesis of the cutaneous lesions of dermatitis herpetiformis. Using a standard immunoperoxidase technique, we labelled perilesional skin biopsies from patients with dermatitis herpetiformis and other inflammatory dermatoses with monoclonal antibodies to CD3, CD4, CD8, alpha/beta T cell receptor, gamma/delta T cell receptor, and IL-2 receptor. We found no differences in the percentage of gamma/delta positive T lymphocytes in skin lesions of dermatitis herpetiformis as compared to other selected inflammatory conditions. These findings suggest that the pathogenesis of the cutaneous lesions of dermatitis herpetiformis is not mediated through gamma/delta T cells, and that the cutaneous lesions may develop through mechanisms different from those operative in the gastrointestinal tract. 相似文献
953.
954.
BACKGROUND: Certain situations dictate conservative management of grade 4 uterine or vaginal vault prolapse in women. The reduction of a prolapse may not be possible if the vagina cannot retain a single pessary. We have used double pessaries in the management of this condition. TECHNIQUE: With the patient in the dorsal lithotomy position, either a Donut or Inflatoball (Milex Products Inc., Chicago, IL) pessary is inserted and pushed into the vagina as far as is comfortable. A second pessary, either a flexible Gellhorn or Shaatz (Milex Products Inc.), then is placed caudad to the first. EXPERIENCE: We have used this approach in five women who have been followed for 7-15 months. There have been no erosions or vaginitis and all the women experienced symptomatic relief. CONCLUSION: In women who want or require conservative management of grade 4 prolapse and are unable to retain a single pessary, the placement of two pessaries often will be successful. 相似文献
955.
Analysis of responses by 151 people to five questions about meat and, in particular, lamb, showed that consumption of lamb on a weekly basis varied widely between consumers. There was some evidence that people who produce their own meat have a higher consumption of lamb than those who do not. A clear preference for either traditional or alternative lamb cuts according to the sex of the respondent was not found. Overall 60% of respondents preferred bone-in as opposed to bone-out leg, 72% preferred midloin to valentine chops and 73% preferred bone-out as opposed to bone-in forequarters. 相似文献
956.
Origins of scaling in natural images 总被引:2,自引:0,他引:2
DL Ruderman 《Canadian Metallurgical Quarterly》1997,37(23):3385-3398
One of the most robust qualities of our visual world is the scale invariance of natural images. Not only has scaling been found in different visual environments, but the phenomenon also appears to be calibration-independent. This paper proposes a simple property of natural images which explains this robustness: they are collages of regions corresponding to statistically independent "objects". Evidence is provided for these objects having a power-law distribution of sizes within images, from which follows scaling in natural images. It is commonly suggested that scaling instead results from edges, each with power spectrum 1/k2. This hypothesis is refuted by example. 相似文献
957.
RA Saunders ML Donahue LM Christmann AV Pakalnis B Tung RJ Hardy DL Phelps 《Canadian Metallurgical Quarterly》1997,115(5):604-608
OBJECTIVES: To determine and compare the incidence of severe, vision-threatening retinopathy of prematurity (ROP) in black and white low-birth-weight infants. DESIGN: Prospective cohort study. SETTING: Seventy neonatal intensive care units in 23 US participating centers in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity. PATIENTS: A total of 4099 premature infants weighing less than 1251 g at birth were enrolled to evaluate the natural history of ROP. This 'Natural History' cohort included 2158 white infants and 1584 black infants who were followed up prospectively according to a Natural History protocol. MAIN OUTCOME MEASURES: Incidence and severity of acute ROP. RESULTS: While ROP occurred with similar frequency in all racial subgroups, severe ROP was less common in black infants. One hundred sixty (7.4%) of 2158 white infants reached threshold ROP (defined as at least 5 contiguous or 8 cumulative clock-hours of stage 3 retinopathy in zone 1 or zone 2 in the presence of "plus disease" [dilation and tortuosity of the posterior pole blood vessels]), but only 51 (3.2%) of 1584 black infants progressed to threshold ROP. Using multiple logistic regression analysis, race emerged as a highly significant factor (P < .001) in the development of threshold disease, even when birth weight, gestational age status at delivery, sex, multiple births, and transport status were considered. CONCLUSIONS: Severe, vision-threatening ROP occurs with greater frequency in low-birth-weight white infants than in low-birth-weight black infants who are seemingly at equivalent risk. The reason for this disparity is unknown. We speculate that differences in retinal pigmentation may confer relative protection against free radical-mediated phototoxic injury in black infants. 相似文献
958.
S Sussman VC Parker C Lopes DL Crippens P Elder D Scholl 《Canadian Metallurgical Quarterly》1995,30(9):1141-1164
Two studies are described which provide evaluations for two brief videotapes developed as supplemental materials in the prevention of tobacco use among African-American adolescents. One videotape (the "soap opera") provides a more general audience-oriented presentation of prevention material and it was filmed primarily at a shopping mall, whereas the other videotape (the "rap") provides a "hip-hop generation" presentation, and it was filmed primarily at an outdoor hangout. The first study compared the two videotapes against each other. The second study compared the two videotapes combined in the same presentation, controlling for order of presentation, against a discussion group control. The results of the two studies indicated few differences in receptivity to the two videotapes among primarily African-American and Latino young adolescents. The rap videotape was rated as more accurate in its depiction of the African-American lifestyle, although both videotapes were equally liked. When shown together, the videotapes were not found to be superior in decreasing behavioral intention to smoke compared to a discussion group control. No change in trial of smoking was observed within or across conditions measured over a pre-post summer interval. These data suggest that "culturally sensitive" videotapes have no more of a short-term effect on youth than do other types of brief interventions which involve minority implementers. 相似文献
959.
960.