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951.
W R Lange J C Ball W H Adler E Brown R Pyle W Hoffman E M Dax 《Public health reports (Washington, D.C. : 1974)》1991,106(4):451-455
Serum specimens obtained from a nationwide sample of parenteral drug abusers (PDAs) during the period 1971-72 had previously been screened for human immunodeficiency virus (HIV) antibodies. Some specimens were considered to be positive to both ELISA and Western blot (WB) analysis. These findings have been a topic of controversy, since HIV was not thought to have penetrated at-risk populations at such an early date. This study was a followup of those PDAs with apparent seropositivity to WB analysis. Of 10 persons followed, only one death (in 1985) was documented, and postmortem findings were inconsistent with HIV infection. Eight of the remaining PDAs were traced and found to be alive and well in 1989. Fresh specimens were obtained from the two persons with the strongest 1971-72 WB staining and were found to be both ELISA and WB negative on retesting. Their T-cell parameters were within normal limits. We concluded that the earlier WB results were most likely false positives and that definitive evidence of HIV infection in the U.S. addict population as early as 1971-72 is still lacking. 相似文献
952.
953.
6-[18F]Fluoro-L-DOPA (FDOPA) is an L-DOPA analog that is used to assess the functional integrity of central dopaminergic systems in vivo with positron emission tomography (PET). FDOPA metabolites from putamen of normal and MPTP-treated monkeys were characterized to correlate FDOPA metabolism changes with those of the endogenous dopamine system. In MPTP-lesioned putamen, 6-[18F]fluorodopamine and dopamine levels were less than 2% those of controls. Increases in endogenous dopamine metabolism were reflected by similar increases in 6-[18F]fluorodopamine metabolites. These results suggest that changes in the central dopamine system biochemistry can be monitored in vivo with FDOPA and PET. 相似文献
954.
D C Hoffman L Berliner J Manzione R Saccaro B E McGivern 《Journal of the American Dental Association (1939)》1986,113(3):407-411
Direct sagittal CT imaging of the TMJ provides several distinct advantages. Most significant is that direct imaging allows noninvasive evaluation of the disk. Direct sagittal CT scanning can confirm a clinical diagnosis of internal derangements as well as monitor splints intended for recapturing of the disk. Furthermore, the CT direct imaging allows excellent views of the bony architecture similar to those obtained with tomography. Used with clinical history and physical examination, CT can provide an excellent diagnostic modality to help provide better care for patients with internal derangement of the TMJ. 相似文献
955.
956.
Splenic salvage following blunt injury can fail when parenchymal bleeding is uncontrollable. To define the usefulness of an argon beam coagulator for hemostasis, we used the instrument in a laboratory trial of partial splenic resection. New Zealand white rabbits, weighing 4 to 5 kg, had sharp excision of the lower half of the spleen. No sutures were used to control hemorrhage from the cut splenic surface or the hilar vessels. Hemostasis was achieved with 2 to 4 seconds of electrocoagulation delivered by a beam of argon gas. All animals survived the procedure and were in good health when killed between the fourth and sixth week following the procedure. At necropsy, the spleen was viable in all animals with no abscess or hematoma. Minimal adhesions from the treated splenic surface to the omentum were found. The scar at the cut surface was 1 mm in depth, and the histology of the remainder of the spleen was normal. In this simulated splenic injury model, argon beam coagulation was uniformly successful in achieving hemostasis. Minimal tissue destruction and lack of infection were noted. The argon beam coagulator may be useful in patients with severe splenic injuries and other situations requiring partial splenectomy. 相似文献
957.
E E Vokes S Vijayakumar P C Hoffman M K Ferguson J D Bitran S Krishnasamy R Jacobs H M Golomb 《Cancer》1990,66(3):437-442
Twenty-three patients with regionally advanced non-small cell lung cancer (NSCLC) (Stage III) were treated with continuous infusion 5-fluorouracil (5-FU) augmented by high-dose oral leucovorin and hydroxyurea and concomitant radiotherapy. This chemoradiotherapy regimen was administered during 5 days of every other week for six cycles (total radiation dose, 6000 cGy). Three patients (13%) had stable disease, 13 patients (57%) had a partial response (PR), and 1 patient (4%) had a complete response (CR). The overall response rate was 61% (95% confidence interval, 41% to 81%). At a median follow-up time of 19 months, the median survival time for all 23 patients was 12 months. The median time to disease progression was 6 months. Twelve patients have had disease progression outside of the chest, and only 3 patients have had intrathoracic disease progression as the site of first failure. The toxicities of this regimen consisted of mild to moderate myelosuppression and moderate degree dermatitis and mucositis. It was concluded that concomitant chemoradiotherapy with this regimen results in high local activity at acceptable toxicity. However, the systemic activity of this regimen was low, resulting in a high distant recurrence rate and a median survival time that was not different from that achieved with standard therapy. Therefore, its use, as defined in this study, cannot be recommended. 相似文献
958.
A 15-year-old white woman, karyotype 46,XX, had an absent vagina and uterus (Rokitansky-Kuster-Hauser syndrome) as well as an atrial septal defect and transphalangeal thumb (Holt-Oram syndrome). The concurrence of the above two syndromes has not been reported on before. 相似文献
959.
The relationship of nasopharyngeal carcinomas and second independent malignancies based on the Radiation Therapy Oncology Group experience 总被引:2,自引:0,他引:2
The authors sought to learn if the incidence of second independent malignancies after the irradiation of carcinomas of the nasopharynx is similar to that observed after treatment of tumors arising in other head and neck sites. One hundred twenty-one patients who had primary carcinomas of the nasopharynx who were treated solely by ionizing radiation (according to the specifications of a Radiation Therapy Oncology Group protocol) were identified and their subsequent well-being was reviewed. Overall there was a 4.1% incidence of second malignancies (2% after 3 years, 5% after 5 years, and 8% after 8 years) with most arising in the upper aerodigestive tract. This rate is significantly less than the rate associated with other head and neck sites. It is not significantly different from the rate of first malignancies observed in an age-matched and sex-matched population. When only those patients who were free of all evidence of neoplastic disease 6 months after the completion of radiotherapy are considered, similar analysis leads to similar outcomes. The authors conclude that the risk of second malignancies after the successful irradiation of carcinomas of the nasopharynx is substantially less than after treatment of tumors at other head and neck sites. 相似文献
960.
Human gingival Langerhans cells stimulate allogeneic lymphocytes: requirement for MHC class II antigens 总被引:1,自引:0,他引:1
Langerhans cells (LC) are antigen-presenting cells which express high levels of Class II MHC antigens on their plasma membranes. While the expression of these antigens on gingival LC has been documented, their functional significance is unclear. In this study, the mixed epithelial cell-lymphocyte culture reaction (MECLR) between stimulator cells (LC) and allogenic lymphocytes was used as an in vitro model for investigating the role of the MHC Class II antigens HLA-DR, -DQ, and -DP in alloantigen presentation by gingival LC. In epithelial cell suspensions prepared from human gingiva, MHC Class II antigen expression (HLA-DR, -DP, -DQ) was confined to CD1a-positive LC. Depletion of Class II antigen-bearing LC from epithelial cells using monoclonal antibodies (L243, B7/21, and SK10) and complement inhibited the ability of epithelial cells to stimulate proliferation in the MECLR. Pre-treatment of epithelial cell suspensions with the same monoclonal antibodies suppressed proliferation in the MECLR, as did direct addition of these antibodies to co-cultures of epithelial cells and lymphocytes. These results indicate that HLA-DQ and -DP, together with DR antigens on gingival LC, are involved in LC-lymphocyte interactions. Since LC are potent antigen presenting cells, alterations in the expression of MHC Class II antigens on the surface of these cells will influence their ability to stimulate lymphocytes during the initiation of the cellular immune response to the accumulation of dental plaque. 相似文献