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A competitive enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody (M898) was developed for detection of bovine antibodies to Leptospira interrogans serovar pomona. This assay was evaluated using field sera (n = 190) with serovar pomona microscopic agglutination test (MAT) titers of > or =100 as the positive population (group A); field sera (n = 1,445) which were negative in the MAT (1:100 dilution) for serovar pomona (group B); and sera (from a specific-pathogen-free cattle herd [n = 210]) which were negative in the MAT (1:100 dilution) for serovars canicola, copenhageni, grippotyphosa, hardjo, pomona, and sejroe (group C). At the cutoff point recommended by receiver operating characteristic (ROC) curve analysis of the combined ELISA results of serum groups A, B, and C, the sensitivity and specificity values were 93.7 and 96.3%, respectively. The value for the area under this ROC curve was 0.977, indicating a high level of accuracy for the ELISA. Similar results were obtained from the analysis of the combined results of serum groups A and B and from the analysis of the combined results of serum groups A and C.  相似文献   
87.
The current study presents findings from the New York Chaplaincy Study about chaplain visits with patients and their families in 13 healthcare institutions in the Greater New York City area during 1994–1996. It documents the distribution of 34,279 clinical visits by religious affiliation, population served (patients, family and friends), and type of healthcare setting (acute care and non-acute care), and analyzes the number and duration of visits with patients by their medical status. Chaplains in acute settings tended to make less frequent but longer visits with patients than chaplains in non-acute settings. On average, chaplains spent less time with patients who were alone than they did during visits with patients whose family was present during the visit or visits with only family members. Average visit duration was positively related to the percentage of visits in each of the 13 facilities that were made in response to referrals (r = .65, p < .05), and the average duration of referred visits was significantly longer (p < .001) than that of non-referred visits (p < .001). The findings are intended to provide a general picture of what these particular chaplains did in these particular institutions over this particular time-period and are not intended to represent a standard of what chaplains should be doing.  相似文献   
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Bone marrow cells (BMC) are involved in the pathogenesis of human cytomegalovirus++ (HCMV) infections, and the hematopoietic cells are probable sites of HCMV latency in healthy donors. In vitro studies have indicated both a direct inhibitory effect of HCMV on proliferation and differentiation of myeloid bone marrow progenitors and an impairment of bone marrow stroma cell function by HCMV. The purpose of the present study was to establish whether the suppressing effect could be limited to subsets of immature CD34+ BMC and to investigate the role of immature cell populations as possible sites of HCMV latency. CD34+ cells from healthy HCMV-seropositive and -seronegative donors were sorted according to the expression of HLA-DR (CD34+ HLA-DR+ and CD34+ HLA-DR- cells). The progenitor growth of hematopoietic progenitor cells from seronegative donors was examined by colony and single-cell assays after in vitro infection with HCMV. To determine the susceptibility of the CD34+ cells to HCMV infection in vitro and in vivo, cells of both subsets from seronegative and seropositive donors were analyzed for the presence of HCMV DNA by polymerase chain reaction. HCMV infection in vitro inhibited the interleukin-1alpha (IL-1alpha)-, IL-3-, granulocyte colony-stimulating factor-, granulocyte-macrophage colony-stimulating factor-, and stem cell factor-induced proliferation in single-cell assays of CD34+ HLA-DR- cells by 34%. In contrast, the colony growth of the CD34+ HLA-DR+ subset was suppressed in cells from only 3 of the 8 donors. However, in vitro HCMV infection of the CD34+ HLA-DR+ progenitor cells inhibited the proliferation of all donors tested when hematopoietic growth factors were used individually to promote progenitor growth. In addition, the formation of burst-forming units- erythroid and colony-forming units-granulocyte, erythrocyte, monocyte, megakaryocyte was reduced 40% to 60% by HCMV in vitro. In contrast, the growth of high proliferative potential colony-forming cells was not inhibited after in vitro HCMV infection. Furthermore, HCMV DNA was detected in both CD34+ HLA-DR- and CD34+ HLA-DR+ progenitors from in vitro-infected HCMV-seronegative donors and cells from HCMV- seropositive donors. Taken together, the early progenitors defined as CD34+ HLA-DR- and CD34+ HLA-DR+ are directly suppressed in their proliferation by HCMV in vitro, and hematopoietic stem cells are also sites of HCMV latency in healthy HCMV-seropositive donors.  相似文献   
89.
Tumor necrosis factor-alpha (TNF-alpha) is a bifunctional regulator of hematopoiesis, and its cellular responses are mediated by two distinct cell surface receptors. TNF-alpha generally inhibits the growth of primitive murine hematopoietic progenitor cells (Lin-Scal+) in response to multiple cytokine combinations, and the p75 TNF receptor is essential in signaling such inhibition. In the present study we show the reverse phenomenon in that TNF-alpha on the same progenitor cell population in combination with stem cell factor (SCF) and interleukin-7 (IL-7) through the p55 TNF receptor can recruit additional progenitors to proliferate. In contrast, TGF-beta 1, another bifunctional regulator of hematopoietic progenitor cell growth, completely blocked SCF plus IL- 7-induced proliferation. TNF-alpha increased the number of responding progenitors, as well as the size of the colonies formed. The synergistic effects of TNF-alpha were seen at the single cell level, suggesting that its effects are directly mediated. Finally, whereas SCF plus IL-7 promoted primarily granulopoiesis, the addition of TNF-alpha switched the differentiation toward the production of almost exclusively macrophages.  相似文献   
90.
Chikungunya virus (CHIKV) was first isolated in humans in 1952, following an epidemic in Tanzania. The origin of the name means “to bend forward or become contorted,” in reference to the posture adopted by patients due to the joint pain that occurs during the infection. Epidemiology data suggest that by the end of 2015, about 1.6 million people had been infected with CHIKV. The acute period of the disease is characterized by high fever, myalgia, joint pain, and severe and disabling polyarthritis, sometimes accompanied by headache, backache, and maculopapular rash, predominantly on the thorax. Around half of the patients will progress to the subacute and chronic phases, that is manifested by persistent polyarthritis/polyarthralgia, accompanied by morning stiffness and fatigue, which could remain for years. Oral features may include gingivitis possibly as a consequence of arthralgia of the hands leading to limited oral health measures as well as burning sensation and oral mucosal ulceration. Treatment in the acute phase includes acetaminophen, and weak opioids (tramadol or codeine) should be used in cases of severe or refractory pain. For patients who have progressed to the subacute stage and who have not had notable benefit from common analgesics or opioids, NSAIDs, or adjunctive pain medications (anticonvulsants or antidepressants) may be of benefit. In patients with moderate‐to‐severe musculoskeletal pain or in those who cannot be given or tolerate NSIADs or opiates, prednisolone should be prescribed.  相似文献   
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