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The development of control strategies for loiasis is of crucial importance in endemic areas and depends heavily on the accurate identification of occult-infected individuals. A polymerase chain reaction (PCR) and nested polymerase chain reaction (nested PCR) were developed and based on sequences of the repeat 3 region (15r3) of the gene encoding a Loa loa 15-kD protein. The assays was performed on 20 blood samples from occult-infected subjects and 30 from field-collected amicrofilaremic individuals. The size of the initial PCR product was 396 basepairs (bp). When this initial amplification using primers 15r3(1) and 15r3(2) was carried out for 30 cycles, the PCR products from three of the 20 occult-infected and five of the 30 amicrofilaremic individuals were visualized after electrophoresis by staining the gel with ethidium bromide. Subsequent Southern blotting and hybridization with the specific probe revealed hybridization in 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples but only after two days of exposure of the blot to the x-ray film. When the nested PCR was carried out (product size = 366 bp, primers 15r3(3) and 15r3(4)), 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples that were positive by Southern hybridization of the initial PCR products were strongly positive by staining with ethidium bromide. Qualitative Southern blotting of the nested PCR products using the same probe previously described confirmed the ethidium bromide staining results after a very short exposure time of 4 hr. These results demonstrate that the nested PCR amplification product is specific and that its sensitivity in detecting occult loiasis is 95%. This approach has significant promise for the screening of large human populations for active loiasis without the requirement for blotting and hybridization of the PCR products.  相似文献   
13.
In cells in which the lipoprotein assembly process had been inactivated by brefeldin A (BFA), membrane-associated apoB-100 disappeared without forming lipoproteins or being secreted, indicating that it was degraded. Reactivation of the assembly process by chasing the cells in the absence of BFA, gave rise to a quantitative recovery of the membrane-associated apoB-100 in the very low density lipoprotein (VLDL) fraction in the medium. These results indicate that the membrane-associated apoB-100 can be converted to VLDL. A new method was developed by which the major amount (88%) of microsomal apoB-100 but not integral membrane proteins could be extracted. The major effect of this method was to increase the recovery of apoB-100 that banded in the LDL and HDL density regions, suggesting that the membrane-associated form of apoB-100 is partially lipidated. We also investigated the role of the microsomal triglyceride transfer protein (MTP) in the assembly of apoB-100 VLDL using a photoactivatable MTP inhibitor (BMS-192951). This compound strongly inhibited the assembly and secretion of apoB-100 VLDL when present during the translation of the protein. To investigate the importance of MTP during the later stages in the assembly process, the cells were preincubated with BFA (to reversibly inhibit the assembly of apoB-100 VLDL) and pulse-labeled (+BFA) and chased (+BFA) for 30 min to obtain full-length apoB-100 associated with the microsomal membrane. Inhibition of MTP after the 30-min chase blocked assembly of VLDL. This indicates that MTP is important for the conversion of full-length apoB-100 into VLDL. Results from experiments in which a second chase (-BFA) was introduced before the inactivation of MTP indicated that only early events in this conversion of full-length apoB-100 into VLDL were blocked by the MTP inhibitor. Together these results indicate that there is a MTP-dependent "window" in the VLDL assembly process that occurs after the completion of apoB-100 but before the major amount of lipids is added to the VLDL particle. Thus the assembly of apoB-100 VLDL from membrane-associated apoB-100 involves an early MTP-dependent phase and a late MTP-independent phase, during which the major amount of lipid is added.  相似文献   
14.
The objective of this study is to determine the effect of solution treatment temperature, quenching media, and various machining sequences on the warpage behavior of aluminum 7249 alloy aged to T6 and T7′ tempers. Large extrusions of 7249 aluminum alloy with fins were cut into 108 “T” sections. The samples were solution-treated, aged, and machined. Three solution temperatures (445, 474, and 505 °C), two quenching media (water and 20% polyalkylene glycol), two aging treatments (T6 and T7′), and three machine sequences were used. The flatness of the samples was measured on the surfaces orthogonal to the z-axis. Three points were on top of both shoulders (six total), six were at the bottom of the sample, and six were on the top of the fin, in the cases where the fin was not milled off. They were then averaged together by surface to represent the overall warpage of each sample.  相似文献   
15.
本文着重介绍了针对青藏线宿营车特殊的地理、使用环境设计开发的集中供暖系统技术,并对其运用成效问题进行探讨.  相似文献   
16.
介绍贵港航运枢纽船闸建筑群采用头部分裂均压式新型避雷针替代原有避雷针防雷,取得了较好的防雷效果。  相似文献   
17.
煤制脱硫剂的微孔结构及其对SO_2/N_2混合气的分离机理   总被引:3,自引:0,他引:3  
研究了以不同挥发份含量的煤为原料、在不同炭化及活化条件下制成的脱硫剂的微孔结构特征和对SO_2的吸附容量,对脱硫剂的形貌进行了扫描电镜观察,根据煤制脱硫剂的孔径分布特征和SO_2分子尺寸,确定出SO_2/N_2混合气的分离机理应属平衡分离。  相似文献   
18.
In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat lumbar (L) 5 dorsal root ganglion (DRG) and areas where afferents from the DRG terminate, the L5 spinal cord and gracile nuclei, following unilateral sciatic nerve transection or crush. From 3 days to 4 weeks following cut or crush injury, the percentage of medium and large BDNF-immunoreactive neurons in the ipsilateral DRG increased significantly compared with those on the contralateral side. Following cut injury, there was no significant change in the percentage of small BDNF-immunoreactive neurons in the ipsilateral DRG; however, the intensity of immunoreactivity of these cells decreased. Following crush injury, however, both the percentage and intensity of small BDNF-immunoreactive neurons in the ipsilateral DRG significantly increased. Following cut injury, the expression of BDNF-immunoreactive axonal fibers decreased markedly in the ipsilateral superficial laminae of the L5 spinal cord and increased significantly in the ipsilateral deeper laminae of the spinal cord and gracile nuclei. Crush injury induced a marked increase in the expression of BDNF-immunoreactive axonal fibers in the superficial laminae of the spinal cord and gracile nuclei. These differences in BDNF response in the DRG and spinal cord after cut or crush injuries may reflect differences in trophic support to the injured DRG neurons and altered neuronal activity in the spinal cord and gracile nuclei following different types of peripheral nerve injury.  相似文献   
19.
Twenty-six daytime NOAA-11 AVHRR images covering the Danish waters are analysed together with 99 cloud-free bulk temperature measurements. The images are cloud screened with a cloud-detection algorithm, which in excess of the usual threshold and variation tests consists of: a min_max-routine which among suspicious pixels points out the cloud contaminated pixels, and a separation of cloud pixels from cold water pixels by means of the correlation coefficient between the channel 4 brightness temperature and the channel 4-channel 5 brightness temperature. In the cloud screened images, the channel 4-channel 5 brightness temperatures do not increase with the satellite zenith angle and do not seem to carry any significant information about the true sea surface temperature (SST). Local meteorological and oceanographic effects are believed to be more important than the channel 4-channel 5 brightness temperatures.  相似文献   
20.
Intensive case management for severely psychiatrically ill patients is a relatively new phenomenon in the private sector. The authors describe a comprehensive case management program designed at Blue Cross Blue Shield of Massachusetts to meet the needs of the most severely ill psychiatric patients in a private managed care environment. The case management program emphasizes involvement of patients in creating comprehensive treatment plans; development of a relationship between case managers, patients and their families, and providers; and clinical coordination between the public and private sectors to create individualized treatment plans. The program's case managers are able to flex the benefit limitations of a managed care or indemnity plan to integrate public and private services and can enlist providers outside a managed care network. The paper describes service utilization by the first 33 patients who participated in the program for one year.  相似文献   
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