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271.
主要介绍了江苏濒危植物珊瑚菜的特征特性、生存现状.江苏沿海野生珊瑚菜种群被证实已灭绝,并探析了其灭绝的原因,为内在因素和外在因素的结合,但人为的外在因素对其生存的影响是致命性的.呼吁保护环境以拯救其它濒临灭绝的物种. 相似文献
272.
273.
Cong-hui Han Qing Liang Bing-zheng Dong Lin Hao Tao Fan Jun-jie Zhang Wen-da Zhang Bo Chen Xiang-zheng Qiu Xiang-ju Zhou Chang-song Pei 《Cell biochemistry and biophysics》2013,66(3):851-853
To develop a transurethral endoscopy technique of the transurethral seminal vesiculoscopy to examine and treat seminal vesicle disease. A total of 61 patients with seminal vesicle disease were diagnosed and treated with the transurethral seminal vesiculoscopy through the distal seminal tracts and vesicles. 58 cases were successfully treated using transurethral seminal vesiculoscopy via the seminal vesicles. The operation took 25 ~ 85 min, with an average of (35.6) mins. In this group, seven cases were diagnosed as ejaculatory orifice cyst, 14 cases had blood clots in the seminal vesicles, and nine patients had stones in the seminal vesicles. All patients were treated properly. Follow-up occurred at 3 months, with two cases showing post-operative discomfort in perineal region. One patient had recurrence with seminal vesiculitis, which improved with treatment. Four infertile patients had a significant increase in sperm count and ejaculation volume and two of these patients were able to naturally inseminate within seven to 18 months post-surgery. This approach enables a new endoscopic technique with the transurethral seminal vesiculoscopy to diagnose and treat seminal vesicle disease through the normal anatomic pathway which can be easily performed with few post-operative complications. 相似文献
274.
Flood control engineering system risk assessment entails fuzziness. An assessment model is developed, based on the improved fuzzy comprehensive assessment method that developed a new index (Sfin ) to judge the assessment class. The model is used to assess the flood control engineering risk of a case in China. The results show that the proposed model in the present article can rationally determine the risk status of a flood control engineering system, and has higher resolution compared to the two conventional methods, fuzzy comprehensive assessment and matter-element model method. The proposed model is flexible and adaptable for determining flood control engineering system risk status. 相似文献
275.
276.
Chen Yao Jian-jun Wei Zu-yu Wang Hui-min ding Dong Li Shi-chang Yan Yong-jiang Yang Zhang-ping Gu 《Cell biochemistry and biophysics》2013,65(2):217-227
Despite the advances of adjuvant chemotherapy and significant improvement of survival, the prognosis for patients with osteosarcoma is generally poor. The search for more effective anti-osteosarcoma agents is necessary and urgent. Here we report that perifosine induces cell apoptosis and growth inhibition in cultured human osteosarcoma cells. Perifosine blocks Akt/mTOR complex 1 (mTORC1) signaling, while promoting caspase-3, c-Jun N-terminal kinases (JNK), and p53 activation. Further, perifosine inhibits survivin expression probably by disrupting its association with heat shock protein-90 (HSP-90). These signaling changes together were responsible for a marked increase of osteosarcoma cell apoptosis and growth inhibition. Finally, we found that a low dose of perifosine enhanced etoposide- or doxorubicin-induced anti-OS cells activity. The results together suggest that perifosine might be used as a novel and effective anti-osteosarcoma agent. 相似文献
277.
278.
Granulation of activated sludge in a continuous flow airlift reactor by strong drag force 总被引:1,自引:0,他引:1
Dandan Zhou Mengyuan Liu Jun Wang Shuangshi Dong Ning Cui Linlin Gao 《Biotechnology and Bioprocess Engineering》2013,18(2):289-299
Most aerobic granule cultivation has been based on the sequencing batch reactor (SBR) and then the factors that affect aerobic granulations were developed in the SBR. However, little work has been done to cultivate aerobic granules in a continuous-flow bioreactor with simple structure that is realistic for engineering. This work is the first to cultivate aerobic granules in a continuous flow airlift fluidized bed reactor (CAFB) possesses a very simple structure and without settling time and starvation time controlling. The configuration of CAFB was the simplest continuous-flow aerobic granular bioreactor reported by now. The majority of granules could be formatted in the CAFB after 12 days cultivation. The effluent COD concentration maintained at 50 ± 10 mg/L for the variable COD loading rate of 3.5 g COD/L/d and 4.8 g COD/L/d, which confirmed that the CAFB performed good anti-shock abilities. CAFB performed good nitrification ability, however, little denitrification was found under the operating conditions of this study. The shear stress acting on the solid phase were hundreds of times stronger in the CAFB than in the SBR at the same aeration strength. It seems CAFB is very efficient for granulation due to the strong shear-force exertion, which is promising for continuous-flow aerobic granular bioreactor. Protein, positive to the hydrophobicity, was predominant in extracellular polymeric substances in the granules, and favored the granules formation in the CAFB combined with the polysaccharides. However, filamentous bulking always happened in 35 days operation of the CAFB, thus further study on the stability of this bioreactor is urgently necessary. 相似文献
279.
Byoung-Shik Shim Jung-ah Choi Ho-Hyun Song Sung-Moo Park In Su Cheon Ji-Eun Jang Sun Je Woo Chung Hwan Cho Min-Suk Song Hyemi Kim Kyung Joo Song Jae Myun Lee Suhng Wook Kim Dae Sub Song Young Ki Choi Jae-Ouk Kim Huan Huu Nguyen Dong Wook Kim Young Yil Bahk Cheol-Heui Yun Man Ki Song 《Journal of microbiology (Seoul, Korea)》2013,51(1):130-135
Influenza viruses are respiratory pathogens that continue to pose a significantly high risk of morbidity and mortality of humans worldwide. Vaccination is one of the most effective strategies for minimizing damages by influenza outbreaks. In addition, rapid development and production of efficient vaccine with convenient administration is required in case of influenza pandemic. In this study, we generated recombinant influenza virus hemagglutinin protein 1 (sHA1) of 2009 pandemic influenza virus as a vaccine candidate using a well-established bacterial expression system and administered it into mice via sublingual (s.l.) route. We found that s.l. immunization with the recombinant sHA1 plus cholera toxin (CT) induced mucosal antibodies as well as systemic antibodies including neutralizing Abs and provided complete protection against infection with pandemic influenza virus A/CA/04/09 (H1N1) in mice. Indeed, the protection efficacy was comparable with that induced by intramuscular (i.m.) immunization route utilized as general administration route of influenza vaccine. These results suggest that s.l. vaccination with the recombinant non-glycosylated HA1 protein offers an alternative strategy to control influenza outbreaks including pandemics. 相似文献
280.