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The study was conducted to estimate the relation between lead exposure and the risk of various symptoms of osteoporosis in male and female battery manufacturing workers by using dual energy X-ray absorptiometry. A total of 18 female and 24 male workers were chosen with the same age range, duty hours per day, work history and weight. A total of 15 healthy controls were chosen with no previous history of bone illness and normal blood lead concentration. Blood lead concentration was measured in all workers and controls. Non-lead elevated subjects were excluded. Bone mineral density was measured by X-ray-based dual-energy X-ray absorptiometry scan machine. Spine, femur neck and radius sites were studied. Results showed that both male and female workers recorded significant elevated levels of lead concentration accompanied by osteoporosis when compared with control. Interestingly, the data revealed that fracture risk in female was significantly higher than male workers. It was concluded that lead poisoning may act as osteoporosis risk factor or co-factor in female workers by activating the conversion of osteopenia to osteoporosis.  相似文献   
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Given the protean manifestations of leptospirosis, adequate laboratory support for diagnosis is necessary. Traditionally, the gold standard is the microscopic agglutination test (MAT) using a panel of Leptospira isolates representing a broad range of serogroups and serovars. It has been proposed that screening with serovars circulating in a region would enhance test performance. We assessed the diagnostic usefulness of MAT using both regionally obtained clinical Leptospira isolates and the specific isolates recovered from the tested patients. Serum obtained from 41 acute febrile patients (obtained on average 7.2 days [SD ± 5.2] after onset of fever) was tested using a standard panel of 24 serovars along with regional isolates recovered from human and animal blood cultures from different regions in Egypt and a patient's own isolate, if available, to establish additional MAT panels. Serum samples tested by a standard 24 panel with a cut-off of >1:800 revealed five patients with positive serology. Only one patient had a positive result using a regional panel or patient's own culture developed MAT. However, the serovar with the highest titers did not match the cultured serovar. Region-specific MATs did not appear to be reliable in detection of infection or in identifying the infecting serovar.  相似文献   
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Procarbazine hydrochloride is an oral alkylating agent with activity against lymphoma. It is most commonly used in the treatment of Hodgkin's disease. The use of procarbazine-containing chemotherapeutic regimens in non-Hodgkin's lymphoma fell out of favor with the advent of CHOP. We report two patients with relapsed and/or refractory follicular lymphoma that achieved a complete and durable remission with a prolonged course of daily procarbazine.  相似文献   
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We aimed to determine an optimal protocol for inducing a focal inflammatory lesion within the rat brain that could be large enough for an easier MRI monitoring while still relevant as a multiple sclerosis (MS) like lesion. We adapted a two-hit model based on pre-sensitization of the Lewis rat with myelin oligodendrocyte protein (MOG) followed by stereotaxic injection of pro-inflammatory cytokines (TNFα + IFNγ) within the internal capsule. We compared the following two strategies to increase focal lesion development for an easier MR translation: (1) a higher sensitization step (MOG50) or (2) a higher cytokine step with lower sensitization (MOG25). Control animals were administered only cytokines without MOG pre-sensitization. Animals were followed with T2, diffusion and T1 post gadolinium weighted images at 1, 3 and 7 days following cytokine injection. Immunostaining was performed at the same time points for macrophages (ED1), myelin (MBP and Luxol Fast Blue) and blood brain barrier integrity (IgG). At day 1, the focal lesions depicted with T2-weighted images were very similar among groups and related to vasogenic edema (high apparent diffusion coefficient (ADC), gadolinium enhancement and IgG extravasation) induced by cytokines irrespective of the pre-sensitization step. Then, at day 3, MOG50 rats developed statistically larger T2 lesions than MOG25 and control rats that were correlated with inflammatory cell accumulation. At day 7, MOG50 rats also showed larger T2 lesions than MOG25 and control rats, together with loss of anisotropy that were correlated with demyelination. In contrast, MOG25 and control rats developed similar MR lesions decreasing over time and almost undetectable at day 7. We conclude that with a high pre-sensitization step, the focal lesion can be monitored by MRI whose signal reflects some features of a MS-like lesion, i.e. edema, inflammatory cell accumulation and later demyelination.  相似文献   
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