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41.
目的:通过检测HBV感染父亲体外受精胚胎中的HBV mRNA以明确HBV父婴传播的意义。方法:以慢性HBV感染父亲体外受精后遗弃胚胎为研究对象,用单细胞RT-PCR检测胚胎中的HBV mRNA。结果:父亲HBV血清标志物阳性者而母亲为HBV血清标志物阴性的9例18个废弃胚胎,在1个胚胎中检测到HBVmRNA,阳性率为1/18(5.6%),84个阴性对照胚胎中未检出特异性HBV mRNA。随访发现实验组和阴性对照组之间临床妊娠率分别为33.3%和44.0%,两者之间差异无明显意义(P>0.05);早期流产率分别为33.3%和9.1%,两者之间无明显统计学意义(P>0.05);胚胎中HBV mRNA信号阳性父亲的体外受精胚胎成功种植,但发生了早期流产;两组均未发生子代HBV感染。结论:HBV mRNA的阳性结果证实了HBV可以通过精子进入早期卵裂胚胎并在其中复制,可能是父婴传播的主要途径;而且HBV可能会干扰胚胎的发育,进一步造成流产等不良结果。  相似文献   
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We present a case of adult umbilical hernia with vertical dislocation along the abdominal wall. The hernial sac arose from the internal ring and connected to the umbilicus 20?mm below the internal ring. The postoperative course was uneventful. Two years and four months after the operation there was no evidence of recurrent hernia even when abdominal pressure was increased, and the umbilicus looked acceptable. An umbilical hernia is usually within the umbilicus. The hernial sac arose from the internal ring so should be called an umbilical hernia not an epigastric hernia. It is unusual that the umbilical hernia dislocates vertically along the abdominal wall, while the umbilicus stays depressed. This atypical form of umbilical hernia has not been described previously as far as we know.  相似文献   
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The remarkable reduction in HIV-related morbidity and mortality as a consequence of the widespread use of highly active antiretroviral therapy (HAART) has led to a growing number of HIV-infected persons and their partners requesting counselling regarding the chances of reproduction. A thoughtful medical evaluation of the couple, which should entail HIV status, screening for genital infections and fertile potential, is needed before considering any reproductive attempt. Given that both sexual and perinatal transmission of HIV is directly correlated with the level of viral replication, being almost negligible in patients with undetectable viremia, HAART should be given to the infected partner to minimize the risk of transmission. Assisted reproduction after 'sperm washing' may further reduce the chances of infection, although this is not within reach or desire for a significant number of HIV-serodiscordant couples. From our perspective, natural conception could now be considered a possible alternative for HIV-serodiscordant couples, as long as complete suppression of viremia with HAART is achieved in the infected partner. The objective of this paper is to propose a protocol that may minimize risks in HIV-discordant couples that have opted for natural conception.  相似文献   
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This paper investigates the removal efficiency of organic matter, nitrogen, phosphorus, coliforms and pathogens from rural domestic wastewater in a two-stage vertical flow multi-soil-layering (MSL) system. The effects of wastewater quality, season and arid climate conditions on pollutants removal efficiency by the system were examined for one year. The experimental setup included two similar MSL systems composed of two layers: soil-mixture-layers (SML) and gravel permeable layers (PL) that are arranged in a brick like pattern. The applied hydraulic loading rate was 1000 L m?2 day?1. Results showed that most of the physicochemical contaminants elimination occurred while the wastewater percolated through the first MSL stage. The second stage demonstrated an improvement in the reduction of all pollutants, especially fecal bacteria indicators and pathogens. The mean overall removal rates performed by the two-stage MSL system were 97% for TSS, 96% for BOD5, 91% for COD, 96% for TN and 95% for TP. For bacterial indicators, the combination of two-stage MSL system achieved high log removals between 2.21 and 3.15 log units. Contaminants reduction processes in MSL technology are more dependent on internal than external environmental factors. The effectiveness of the two-stage MSL system to treat domestic wastewater was strongly influenced by wastewater quality. Significant relationships between influent contaminants level and their removal efficiency were found. The efficiency of MSL technology to reduce contaminants is not sensitive to season and air temperature fluctuations. This is due to the capacity of MSL system materials to withstand the air temperature variation, which highlights one of the advantages of MSL’s technology. Wastewater quality is the most important factor affecting the removal of contaminants in the MSL, which could be a critical parameter to considered when designing MSL system. Two-stage MSL system achieved a high treated wastewater quality amenable for treated wastewater reuse in agriculture recommended by Moroccan code of practice. Therefore, the combination of two-stage vertical flow MSL system could be considered an efficient and promising domestic wastewater treatment solution in arid countries to promote environmental protection and wastewater reuse.  相似文献   
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To meet the performance goals of fifth generation (5G) and future sixth generation (6G) optical wireless communication (OWC) and sensing systems, we seek to develop low-cost, reliable, compact lasers capable of sourcing 5–20 Gb/s (ideally up to 100 Gb/s by the 2030s) infrared beams across free-space line-of-sight distances of meters to kilometers. Toward this end, we develop small arrays of electrically parallel vertical cavity surface emitting lasers (VCSELs) for possible future use in short-distance (tens of meters) free-space optical communication and sensing applications in, for example, homes, data centers, manufacturing spaces, and backhaul (pole-to-pole or pole-to-building) optical links. As a starting point, we design, grow by metal–organic vapor phase epitaxy, fabricate, test, and analyze 980 nm top-emitting triple VCSEL arrays. Via on-wafer high-frequency probe testing, our arrays exhibit record bandwidths of 20–25 GHz, optical output powers of 20–50 mW, and error-free data transmission at up to 40 Gb/s—all extremely well suited for the intended 5G short-reach OWC and sensing applications. We employ novel p-metal and top mesa inter-VCSEL connectors to form electrically parallel but optically uncoupled (to reduce speckle) arrays with performance exceeding that of single VCSELs with equal total emitting areas.  相似文献   
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