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51.
We investigated the capacity of human interleukin (IL) 7 to induce proliferation of B cells. Purified tonsillar B cells were cultured in the presence of IL7 with Staphylococcus aureus Cowan I (SAC) or anti-μ beads as co-mitogens. IL 7 supported a dose-dependent proliferation of anti-μ-activated B cells but did not significantly support proliferation of SAC-activated B cells. When B cells were separated on Percoll gradient into small (60%-80%) and large (50%–60%) B cells and then cultured with anti-μ beads, IL7 acted on both cell populations equally well. IL7 and BCGF (low molecular weight) were synergistic in their proliferative action on anti-μ-activated B cells in a 5-day culture. On the other hand, synergistic effect of IL 7 on activated B cells was not evident in the presence of any other factor recombinant [(r)IL 1β, rIL2, rIL3, rIL4, rIL5, rIL6, recombinant tumor necrosis factor-α, recombinant lymphotoxin, recombinant granulocyte-monocyte colony-stimulating factor and recombinant interferon-γ] we tested. IL7 did not induce IgG secretion by activated B cells.  相似文献   
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Serum Adenosine Deaminase (ADA) enzyme levels were estimated in 61 patients with symptoms and signs suggestive of Pulmonary Tuberculosis and correlated with "Gold standards" such as smear positivity of sputum for Acid Fast bacilli, Tuberculin skin testing and Radiological evidence. The mean ADA levels in smear and Tuberculin negative patients was 13.13 +/- 5.97 u/L, while in those with smear and/or strongly positive Tuberculin reaction, the mean levels of ADA were 33.52 +/- 15.22 u/L. The mean serum ADA levels in 25 healthy voluntary donors with no evidence of active or old Tuberculous lesion, were found to be 16.5 +/- 3.18 u/L. The specificity, sensitivity, positive predictive value and negative predictive value of the test was found to be 87%, 71%, 90% and 66.5% respectively. The results conclude that the serum ADA value is sufficiently useful in identifying those patients in whom the diagnosis of Pulmonary Tuberculosis should be actively considered.  相似文献   
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The Journal of Behavioral Health Services & Research - Statistical reliability of the Treatment Perceptions Survey (TPS) questionnaire was examined using data from 19 California counties. The...  相似文献   
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There is a deficit of literature regarding the association between nickel allergy–induced symptoms and implanted devices. This report describes a case of nickel allergy causing debilitating migraine-like symptoms, failing to resolve with medical therapy, requiring surgical removal of the device and repair of the defect.  相似文献   
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Bulletin of Environmental Contamination and Toxicology - Halogenated compounds are one of the largest groups of environmental-hazardous chemicals. The removal of the halogen atom from the substrate...  相似文献   
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Tuberculosis of the middle ear it a rare disease. Due to change in the typical clinical pattern and decrease in incidence, there is a delayed or missed diagnosis and can lead to increased morbidity. We pretent 5 cases of Tuberculous Otitis Media treated over a period of 2 years, highlighting the fact that it must be considered as a differential diagnosis of persistent suppurative otitis media.  相似文献   
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Conventional cancer therapies such as surgery, chemotherapy and/or radiotherapy, are not always successful in providing long-term survival for cancer patients. One of the major problems with conventional cancer therapies is their inability to eradicate residual/metastatic tumor cells that are resistant to therapy. Therefore, it is necessary to develop new methods for treating such cancer cells in order to improve the clinical outcome of these patients. Despite antitumor effector mechanisms working against cancer cells in the host's body, tumor-cell-induced immunosuppression and or antigenic modulation by the tumor cells often help tumor cells escape host defense mechanisms. Therefore, one approach for treating residual cancer would be to enhance the host's own immunological/antitumor defense mechanisms. Immune cells that have a significant role in mediating antitumor responses include: T lymphocytes; natural killer (NK) cells; macrophages; and B lymphocytes. The ability of these immune cells to effectively destroy malignant cells is carefully governed by chemical mediators in the form of proteins otherwise known as cytokines. Many cytokines (interleukins, interferons, and tumor necrosis factor) have been shown to enhance in vitro and in vivo effector cell antitumor cytotoxic activities. Utilization of cytokines in conjunction with effector cells can also mediate significant antitumor responses in both animal models and cancer patients. One of the major problems associated with systemic treatment with cytokines is the development of dose limiting toxicities. Currently, attempts to reduce this problem include developing techniques to allow for the preferential release of cytokines in proximity to the tumor cell. In this regard, effector cells or tumor cells that have been genetically engineered to secrete cytokine(s) may be useful in localizing an immune response, preferably at the tumor site. Clinical trial using cytokine gene transfected cells for treating cancer are currently under investigation. With the availability of recombinant lymphokines and with our ability to genetically modify effector cells and tumor cells this hopefully will allow us to improve current therapeutic modalities for treating cancer.  相似文献   
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