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941.
Indigenous Indian groups comprise approximately 20% of Ecuador's population, the third largest percentage in all of Central or South America, yet immunogenetic data on these groups are lacking in the literature. In the course of population migration studies, sera collected from 65 Ecuadorians living in the northern province of Esmeraldas were typed for six GM and two KM markers. The study population consisted of 47 Cayapa Indians and 18 blacks of African origin, descendants of slaves imported into the area during the seventeenth century. The Cayapa demonstrated three GM phenotypes, two of which are common to other South American Indian tribes. The frequency of KM1 positive Cayapa Indians (63%) is similar to other South American Indian tribes, but is significantly greater than the Huaorani of eastern Ecuador (2%), the only other Ecuadorian Indian group for whom limited immunoglobulin allotype data are available (chi 2 = 35.8, P < 0.0001). 相似文献
942.
943.
PURPOSE: To determine the potential economic and policy implications that result from incorporating paclitaxel into first-line therapy for stage 3 and 4 ovarian cancer patients in the province of Ontario, Canada. METHODS: A cost-effectiveness analysis was conducted to compare cisplatin/cyclophosphamide (CC), a standard therapy, with cisplatin/paclitaxel (CT). Based on survival curves from a clinical trial, mean costs and survival were calculated. Sensitivity analyses were conducted based on altering the duration of paclitaxel infusion, discount rates, and efficacy of paclitaxel. RESULTS: The mean survival duration is prolonged from 2.06 years with the standard therapy to 2.44 years with the paclitaxel combination. The paclitaxel therapy is more expensive, with a mean cost of $17,469 (Canadian) per patient treated with CT compared with $5,228 per patient with CC. The incremental cost-effectiveness ratio is $32,213 per year gained. Sensitivity analyses show that the conclusions remain unchanged. The use of CT as first-line treatment for advanced ovarian cancer patients in Ontario requires an additional $9 million per year over and above the present costs to treat this patient population. CONCLUSION: Although paclitaxel-based therapy prolongs survival, it comes at an increased cost. It may not be possible to fund paclitaxel treatment using resources presently allocated to first-line chemotherapy for advanced ovarian cancer. The policy implications for absorbing the cost of paclitaxel in the context of a publicly funded health care system are discussed. 相似文献
944.
945.
HR Berthoud LM Patterson AE Willing K Mueller WL Neuhuber 《Canadian Metallurgical Quarterly》1997,746(1-2):195-206
The presence and distribution of vagal fibers and terminals throughout esophagus and gastrointestinal tract that could be anterogradely labeled by nodose ganglion tracer injections was quantitatively assessed in capsaicin- and vehicle-pretreated adult rats, in order to identify the capsaicin-resistant population. Up to 90% of the intraganglionic laminar endings (IGLEs), in the myenteric plexus of the esophagus, and 70-90% in the stomach, as well as 57% of the intramuscular endings or arrays (IMAs) in the fundic stomach survived the capsaicin treatment, while in the upper small intestine only few and in the lower small intestine, the cecum and colon, virtually no IGLEs survived capsaicin treatment. Intramucosal terminals were not assessed. Furthermore, gastric balloon distension-induced c-Fos expression in the dorsal vagal complex was not significantly decreased in capsaicin-treated rats. It is concluded that among primary vagal afferents there is a capsaicin-resistant population that primarily innervates the esophagus and upper gastrointestinal tract, and a capsaicin-sensitive population that innervates mainly the lower tract. At least vagal gastric tension-sensitive afferents also seems to be functionally intact in that they may be capable of synaptically activating second-order neurons in the brainstem. 相似文献
946.
A Carbone G Gaidano A Gloghini LM Larocca D Capello V Canzonieri A Antinori U Tirelli B Falini R Dalla-Favera 《Canadian Metallurgical Quarterly》1998,91(3):747-755
This study was aimed at defining the histogenesis of the pathologic spectrum of acquired immunodeficiency syndrome-related non-Hodgkin's lymphomas (AIDS-NHL), including AIDS-related small noncleaved cell lymphoma (AIDS-SNCCL), AIDS-related large noncleaved cell lymphoma (AIDS-LNCCL), AIDS-related large cell immunoblastic lymphoma plasmacytoid (AIDS-IBLP), and AIDS-related primary effusion lymphoma (AIDS-PEL). Forty-six cases of AIDS-NHL were investigated for the expression pattern of BCL-6, a protein specifically expressed by germinal center (GC) B-cells, and CD138/syndecan-1 (syn-1), a marker of post-GC B-cell differentiation. Expression of BCL-6 and syn-1 segregated two major phenotypic patterns among AIDS-NHL: (1) the BCL-6+/syn-1- pattern associated with AIDS-SNCCL and AIDS-LNCCL; (2) the BCL-6-/syn-1+ pattern associated with AIDS-IBLP and AIDS-PEL. Among systemic AIDS-NHL infected by Epstein-Barr virus (EBV), expression of the EBV-encoded latent membrane protein-1 (LMP-1) preferentially associated with the BCL-6-/syn-1+ profile. Analysis of nonneoplastic lymph nodes showed that the two phenotypic patterns detected in AIDS-NHL correspond to physiologic stages of B-cell development, i.e., GC B-cells (BCL-6+/syn-1-) and preterminally differentiated post-GC B-cells (BCL-6-/syn-1+). Thus, BCL-6+/syn-1- AIDS-NHL reflects a GC stage of differentiation, whereas AIDS-NHL which are BCL-6-/syn-1+, and LMP-1+ when infected by EBV, derive from B cells that have entered post-GC plasmacell differentiation. These findings are relevant for the pathogenesis and differential diagnosis of AIDS-NHL. 相似文献
947.
948.
RT Lie S Rasmussen H Brunborg HK Gjessing E Lie-Nielsen LM Irgens 《Canadian Metallurgical Quarterly》1998,316(7141):1343-1347
OBJECTIVE: To use familial patterns of recurrence of pre-eclampsia to investigate whether paternal genes expressed in the fetus contribute to the mother's risk of pre-eclampsia and whether mother's susceptibility to pre-eclampsia is related to maternal inheritance by mitochondrial DNA. DESIGN: Linked data on pregnancies of different women who had children with the same father, and subsequently linked data on pregnancies of half sisters who either had same mother and different fathers or had same father and different mothers. SETTING: Population based data from the Medical Birth Registry of Norway covering all births since 1967 (about 1.7 million) and the Norwegian Central Population Register. MAIN OUTCOME MEASURES: Relative risk of pre-eclampsia after a previous pre-eclamptic pregnancy in the family. Relative risks approximated by odds ratios. RESULTS: If a woman becomes pregnant by a man who has already fathered a pre-eclamptic pregnancy in a different woman her risk of developing pre-eclampsia is 1.8 (95% confidence interval 1.2 to 2.6). If the woman has a half sister who had pre-eclampsia and with whom she shares the same mother but different fathers the risk of pre-eclampsia is 1.6 (0.9 to 2.6). If the two sisters have the same father but different mothers the risk is 1.8 (1.01 to 2.9). CONCLUSIONS: Both the mother and the fetus contribute to the risk of pre-eclampsia, the contribution of the fetus being affected by paternal genes. Mitochondrial genes, which are transmitted by mothers, do not seem to contribute to the risk. 相似文献
949.
PS Eastman DE Shapiro RW Coombs LM Frenkel GD McSherry P Britto SA Herman RS Sperling 《Canadian Metallurgical Quarterly》1998,177(3):557-564
Maternal samples were assessed from 96 women enrolled in Pediatric AIDS Clinical Trials Group protocol 076 to determine the prevalence of human immunodeficiency virus type 1 (HIV-1) genotypic zidovudine resistance at entry, if zidovudine resistance developed on study, and the role of zidovudine resistance in vertical transmission of HIV-1 despite zidovudine therapy. Low and high levels of genotypic resistance were assessed by differential hybridization, oligoligation, or direct sequencing of plasma HIV-1 RNA for codons K70R and T215Y/F. None of the women had high-level genotypic resistance to zidovudine at study entry or delivery. For low-level zidovudine resistance, the 95% confidence intervals were 0.3%-6.8% for baseline prevalence and 0.3%-14% for delivery incidence. Low-level zidovudine resistance, adjusted for plasma viral RNA level at delivery, was not strongly associated with an increase in vertical transmission risk (odds ratio, 4.8; 95% confidence interval, 0.2-131; P = .35). 相似文献
950.
Twelve cases of ovarian metastases from cervical carcinomas, most with clinical manifestations of ovarian involvement, are reported. The patients were 23-73 years of age (average, 43 years). The ovarian and cervical tumors were synchronous in eight patients; in three, ovarian tumors were discovered 10 months, 2.5, and 3 years after the detection of a cervical neoplasm. In one patient, the cervical tumor was not discovered until autopsy 7 months after presentation. Four patients had abdominal swelling or distention, three had vaginal bleeding, three had an abnormal Papanicolaou smear, and two had masses discovered during pelvic examination. The ovarian tumors, six of which were bilateral, ranged from 5-17 cm (average, 9.5 cm) in maximal dimension in 11 patients; in the 12th patient, the involved ovary was not enlarged. The cervical tumors were grossly evident in 10 patients. They were usually deeply invasive, often with extracervical extension. Four were squamous cell carcinomas; two, small cell carcinomas; one, a mixed small cell carcinoma and adenocarcinoma; one, a mixed poorly differentiated carcinoid and adenocarcinoma; two, adenosquamous carcinomas; one, a transitional cell carcinoma; and one, an undifferentiated carcinoma. Various features, including bilaterality of the ovarian tumors, the finding that the histologic features of the ovarian tumors typically were unusual for a primary ovarian neoplasm, and the presence of extensive extracervical disease, led to the conclusion that the ovarian tumors were metastatic from the cervix. Although ovarian metastases of cervical carcinoma are uncommon, this series illustrates that, occasionally striking examples with clinical manifestations of ovarian involvement occur. 相似文献