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21.
目的:为阐明大山区(云南和四川省)有钉螺而无日本血吸虫病流行地区(简称:有螺无病地区)钉螺在流行病学中的意义及为制定防治方案提供依据。方法:选择大山区4个有代表性有螺无病村的钉螺,以所在省的日本血吸虫毛蚴在实验室进行群体感染,钉螺与毛蚴比例分别为1∶40和1∶90。结果:4个有螺无病村的钉螺均能为日本血吸虫毛蚴感染,其中,四川省两个有螺无病村钉螺体内的日本血吸虫毛蚴可发育至尾蚴阶段。结论:云南、四川省有螺无病地区钉螺在适宜的环境和一定数量的传染源的条件下可以为所在省的血吸虫毛蚴感染,大山区有螺无病地区为潜在的日本血吸虫病流行区,应加强对这类地区日本血吸虫传染源输入的监测工作。  相似文献   
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目的 查明全民食盐加碘后贵州省儿童甲状腺肿大 (甲肿 )率消长反常现象的原因。方法 采用点面结合的“典型调查”方法 ,即先用触诊法初筛贵州省 19所小学校的适龄儿童 ,然后从中遴选出 度甲肿率较高的并有层次代表性的 3所学校纳入全面调研的视野。结果 儿童甲肿率消长反常现象在贵州省较为普遍 ,甲肿病情严重程度的排序是村屯级 >乡镇级 >县城级 >省城级。结论 高甲肿率与当地多种因素密切相关 ,水硬度大、辣椒氟严重超标以及贫困等因素在致病过程中发挥着修饰性放大作用。这一结论有待进一步通过病例对照研究和前瞻性队列研究证实。  相似文献   
24.
Combining high biodiversity with high yields in tropical agroforests   总被引:4,自引:0,他引:4  
Local and landscape-scale agricultural intensification is a major driver of global biodiversity loss. Controversially discussed solutions include wildlife-friendly farming or combining high-intensity farming with land-sparing for nature. Here, we integrate biodiversity and crop productivity data for smallholder cacao in Indonesia to exemplify for tropical agroforests that there is little relationship between yield and biodiversity under current management, opening substantial opportunities for wildlife-friendly management. Species richness of trees, fungi, invertebrates, and vertebrates did not decrease with yield. Moderate shade, adequate labor, and input level can be combined with a complex habitat structure to provide high biodiversity as well as high yields. Although livelihood impacts are held up as a major obstacle for wildlife-friendly farming in the tropics, our results suggest that in some situations, agroforests can be designed to optimize both biodiversity and crop production benefits without adding pressure to convert natural habitat to farmland.  相似文献   
25.
Human filariasis due to Loa loa differs from other filariasis in that the majority of infected subjects are without circulating microfilariae (occult loiasis). In search for alternative diagnostic methods, which do not depend on circulating microfilariae or the (rather infrequent) eye-passage of adult worms, it was shown earlier that IgG4 antibodies directed against Loa loa adult worm antigen are apparently a good marker of occult loiasis and specific with regard to the sympatrically occurring Mansonella perstans . In this study we evaluated an IgG4 antibody-based ELISA using crude extract of Loa loa microfilariae (which is easier to obtain than adult worm) to estimate the prevalence of loiasis in 3 villages in South-East Gabon. Of 222 examined individuals (80 children < 16 years, 142 adults) 44 (20%) carried Loa loa microfilariae and 170 (77%) M. perstans . Using the mean OD-value + 1 standard deviation of 9 sera from patients solely infected with M. perstans (from the Gambia, where Loa loa is not endemic) as a cut-off, 35 of the 44 microfilaraemic Loa loa patients and 2 of the 9 Gambian controls were positive. This shows that our method had a sensitivity of 80% and a specificity of 78%. Among the remaining 178 subjects who had no microfilariae of Loa loa , as many as 97 (55%) had significant levels of specific IgG4 antibodies against Loa loa , suggesting that they carried occult loiasis. The mean IgG4 level in these putatively occult loiasis patients was slightly but significantly lower than in microfilaraemic subjects ( P < 0.03). In conclusion, despite the limited sensitivity and specificity of our method, IgG4- ELISA at present is a very useful tool in estimating the real prevalence of loiasis in epidemiological surveys and at the individual level can confirm the diagnosis of L. loa amicrofilaraemic subjects with clinical signs suggesting loiasis.  相似文献   
26.
梁敏  刘丽萍  胡伟  史秋晨  魏彩 《安徽医药》2011,15(7):915-916
目的探讨按病区排药和按药品排药两种方法对静脉用药调配中心工作效率的影响。方法总共20个工作日,两种排药方法各排药10 d,统计配置时排药、核对、配液、复核和分筐的时间,计算其平均值,进行两组间比较。结果按病区顺序排药时平均每袋静脉输液的配置时间为137.0 s,而按药品顺序排药时则为121.9 s,两组间差异显著。按病区顺序排药时平均每袋静脉输液排药、配液和复核环节的时间分别为36.3、54.1和10.1 s,而按药品顺序排药时则分别为30.9、44.5和9.3 s,两组间差异显著;核对和分筐时间在两组间无显著性差异。结论按药品顺序排药可缩短静脉用药调配中心静脉输液配置时间,应作为首选排药方法。  相似文献   
27.
分析了2001~2005年南昌市急性血吸虫感染(简称急感)疫情资料,共发生急感156例,其中男性119例(76.3%),女性37例(23.7%),16~55岁的青壮年发病率最高(70.5%),农民和学生为急感发病的主要人群,感染方式以戏水、游泳和捕鱼捞虾为主,5~12月均有发病,其中7~9月为高峰季节,出现突发疫情1起。  相似文献   
28.
To date, there is a dearth of information on canine parvovirus-2 (CPV-2) from the Caribbean region. During August–October 2020, the veterinary clinic on the Caribbean island of Nevis reported 64 household dogs with CPV-2-like clinical signs (hemorrhagic/non-hemorrhagic diarrhea and vomiting), of which 27 animals died. Rectal swabs/fecal samples were obtained from 43 dogs. A total of 39 of the 43 dogs tested positive for CPV-2 antigen and/or DNA, while 4 samples, negative for CPV-2 antigen, were not available for PCR. Among the 21 untested dogs, 15 had CPV-2 positive littermates. Analysis of the complete VP2 sequences of 32 strains identified new CPV-2a (CPV-2a with Ser297Ala in VP2) as the predominant CPV-2 on Nevis Island. Two nonsynonymous mutations, one rare (Asp373Asn) and the other uncommon (Ala262Thr), were observed in a few VP2 sequences. It was intriguing that new CPV-2a was associated with an outbreak of gastroenteritis on Nevis while found at low frequencies in sporadic cases of diarrhea on the neighboring island of St. Kitts. The nearly complete CPV-2 genomes (4 CPV-2 strains from St. Kitts and Nevis (SKN)) were reported for the first time from the Caribbean region. Eleven substitutions were found among the SKN genomes, which included nine synonymous substitutions, five of which have been rarely reported, and the two nonsynonymous substitutions. Phylogenetically, the SKN CPV-2 sequences formed a distinct cluster, with CPV-2b/USA/1998 strains constituting the nearest cluster. Our findings suggested that new CPV-2a is endemic in the region, with the potential to cause severe outbreaks, warranting further studies across the Caribbean Islands. Analysis of the SKN CPV-2 genomes corroborated the hypothesis that recurrent parallel evolution and reversion might play important roles in the evolution of CPV-2.  相似文献   
29.
目的 掌握甘肃省碘缺乏病高危地区碘缺乏病防治现状,为制订碘缺乏病的防治策略提供依据.方法 2007 - 2009年选择12个碘缺乏病高危县,在全县范围内搜索所有1997年1月1日以后出生的疑似克汀病患者.在每个县抽取3个乡,在每个乡抽取2个村,在每个村小学,选择40名8~ 10岁儿童进行甲状腺检查、尿碘测定、智商测查;每个村选择30名育龄妇女进行尿碘测定,并对其家中食盐进行半定量检测,同时对当地碘盐相关情况进行调查.结果 12个县中,共搜索到120例疑似克汀病患者,确诊7例.儿童甲状腺B超肿大率为6.8%(290/4281),夏河县、临潭县、卓尼县、舟曲县和东乡县的肿大率均>5.0%,其中夏河县、临潭县和东乡县均>10.0%.儿童平均智商为82.38.儿童尿碘中位数为180.34 μg/L,尿碘<50.00 μg/L的比例为11.0%(482/4383).育龄妇女尿碘中位数为175.91 μg/L,尿碘<50μg/L的比例为16.5%(126/762).其中夏河县、东乡县育龄妇女尿碘中位数分别为95.24 μg/L和66.30 μg/L.12个县中有8个县的碘盐覆盖率在95.0%以上,其余4个县的碘盐碘盐覆盖率均<85%,其中广河县和东乡县的碘盐覆盖率仅为39.2%(47/120)和66.7%(120/180).14.9%(206/1380)的群众认为购买碘盐不方便;87.7%(1210/1380)认为目前的碘盐价格超出可接受的范围;29.9%(413/1380)的家庭主妇知道预防缺碘的方法.结论 影响碘缺乏病高危地区防治的因素广泛存在,应加强碘缺乏病高危地区监测,适时采取有效措施,确保重点人群充足的碘营养.同时还应加强以碘盐为主的综合防治措施的落实,建立碘缺乏病防治长效机制.  相似文献   
30.
The incidence of severe burn is extremely high in the Low and Middle Income Countries with an estimated 90% of the world incidence of which 50% is in South East Asia. Through an earlier analysis of 11,196 burn admission over 8 years (1993–2000—Phase I) to our burn unit we established the endemic nature of the injury [Ahuja RB, Bhattacharya S. An analysis of 11,196 burn admissions and evaluation of conservative management techniques. Burns 2002;28:555–61]. A continued analysis of 5566 burn admissions over the next 7 years (2001–2007—Phase II) and its comparison with the Phase I reveals a significant change in the epidemiological profile. The average yearly admissions have fallen by 43.14%, from 1399.5 patients in Phase I to 795.14 patients in Phase II. This fall in average yearly admissions is predominant in the age group 16–35 years (52.61% decline) and 36–55 years (46.51% decline). The overall female to male ratio has also changed from 1.26:1 to 0.91:1. However, the overall mean %TBSA burn has reduced only mildly from 49.12% TBSA in Phase I to 44.39% in Phase II. During Phase II there was also a significant decline of 46.93% and 56.25% in the yearly admission of flame and scald burn respectively. Non-intentional incidents still remain the main mode of injury accounting for 87.12% in Phase I and 89.89% in Phase II. But, the yearly admissions of non-intentional burns fell from 1219.25 in Phase I to 714.71 in Phase II, which is a significant drop of 41.38%. Kitchen continues to dominate as the main location for flame incidents, but the yearly admission rate from kitchen accidents dropped from 897.5 patients in Phase I to 368.43 patients in Phase II. At the same time, liquefied petroleum gas (LPG) leaks which accounted for only 0.72% of all kitchen accidents in Phase I rose to 10.74% in Phase II. Another redeeming feature is the reduction in overall mortality from 51.8% in Phase I to 40.20% in Phase II. Interestingly, a very significant negative correlation exists (being significant at 0.01 level—2 tailed) between burn admissions and the yearly per-capita income of Delhi, from 1993 to 2005, to prove that the incidence and profile of burns directly reflects the economic development of the society. We see this as the first long term study from a burn unit of a developing country to directly reflect this association of burn incidence and its changing profile with economic prosperity.  相似文献   
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