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991.
不同检测方法对粪类圆线虫钩虫检出率的比较 总被引:1,自引:0,他引:1
杜尊伟 姜进勇 Peter Steinmann 王剑 周卉 吕山 王学忠 刀天有 刀宏祥 朱建平 张老三 陈绍秋 倪坎 陈然 苏梅惠 李鸿兵 车英 周晓农 《中国血吸虫病防治杂志》2009,21(1):64-66
目的用不同方法检查粪便中的粪类圆线虫和钩虫,掌握检测粪类圆线虫的方法。方法在云南省勐海县选择土源性线虫感染率相对高的自然村1个,以户为单位随机抽样,采用改良加藤法(Kato-Katz法)、Koga法和Baerm ann法3种粪便检查方法对粪样进行检查,每人送检粪样3次。结果粪类圆线虫阳性率Kato-Katz法为0,Koga法为11.72%,Baerm ann法为12.55%。钩虫阳性率Kato-Katz法为64.44%,Koga法为57.74%,Baerm ann法为4.60%。结论Baer-m ann法仅适用于粪类圆线虫检测,Koga法可用作钩虫和粪类圆线虫检测,而Kato-Katz法仅适用于钩虫检测。 相似文献
992.
We recently developed a quantitative peptidomics method using stable isotopic labels and mass spectrometry to both quantify
and identify a large number of peptides. To test this approach and screen for peptides regulated by cocaine administration,
32 Cpe
fat/fat mice and 16 wild-type mice were treated twice daily for 5 d either with saline or 10 mg/kg cocaine. Peptides were extracted
from striatum, hypothalamus, hippocampus, and trimethylammonium butyrate containing either nine deuterium or nine hydrogen
atoms. Pools of heavy- and light-labeled peptides were combined, purified on an anhydrotrypsin affinity column, and analyzed
on a reverse-phase column coupled to an electrospray ionization quadrapole time-of-flight mass spectrometer. Changes in peptide
levels upon cocaine treatment were determined from the relative peak intensities of the cocaine versus saline peaks, and peptides
were identified from collision-induced dissociation spectra. Ten peptides were found to increase or decrease in each of two
separate analyses from distinct groups of mice. Peptides found to increase corresponded to fragments of proenkephalin, prothyrotropin-releasing
hormone, provasopressin, proSAAS, secretogranin II, chromogranin B, and peptidyl-glycine-α-amidating mono-oxygenase in the
hypothalamus. The same peptidyl-glycine-α-amidating mono-oxygenase peptide decreased in the prefrontal cortex, along with
striatal neurokinin B and two unidentified peptides. Thirty other peptides were not substantially affected by cocaine treatment
in both replicates. Taken together, the quantitative peptidomics approach provides an efficient method to screen for changes
in a large number of peptides. 相似文献
993.
994.
Kuo‐Yang Tsai Che‐Chun Su Yo‐Yu Lin Jian‐An Chung Ie‐Bin Lian 《Community dentistry and oral epidemiology》2009,37(6):555-561
Background: Betel quid chewing and cigarette smoking are two of the risk factors for some dental diseases as well as oral cavity cancer in Taiwan. The aim of the study was to quantify these factors in oral cavity cancer patients and compare the prevalence of these factors in patients and the general population. Methods: A questionnaire was designed to evaluate betel quid chewing, cigarette smoking and alcohol drinking in 254 patients, who had squamous cell carcinoma of the oral cavity, and had received surgical excision at the Changhua Christian Hospital in Taiwan between 2005 and 2008. The results were compared with those of population of Taiwan, based on a nation‐wide survey with sample of 26 744 people. Results: We found that more than 80% of the male patients were both betel quid chewers and smokers. Few women in the survey practiced betel quid chewing, cigarette smoking or alcohol drinking. Chewers and smokers usually started the habits in their 20s. On average, a chewer patient consumed 12 508 betel quid pieces per year, for 23.3 years before the diagnosis of oral cavity cancer, making the total amount of betel quid consumed nearly 310 000 pieces; and a smoker patient consumed 469 packs per year, for 28.5 years before diagnosis, making the total number of about 14 000 packs. Patients with both habits had the age at diagnosis 4 years earlier than the smoker‐only patients, 5 years earlier than the chewer‐only patients, and 6 years earlier than those with neither. Conclusions: On average, it took two decades of betel quid chewing and cigarette smoking before oral cavity cancer diagnosis, making the life‐time consumption of these substances an astonishing amount. Betel quid chewing and cigarette smoking patients are more likely to be diagnosed with oral cavity cancer at a younger age than those who have just one habit or none. Patients that smoke more are not only more likely to be diagnosed at a younger age, but also at an advanced stage. 相似文献
995.
Chen‐Yi WU Hsiao‐Yun HU Nicole HUANG Cheng‐Yun PU Hsi‐Che SHEN Yiing‐Jeng CHOU 《The Journal of dermatology》2010,37(5):463-470
Varicella zoster virus (VZV) causes varicella, and may reactivate to cause herpes zoster later in the life of the host. It has been previously observed that exposure to VZV may boost the host’s latent immunity. Health‐care workers who are frequently exposed to ill patients ought to receive a protective effect. We investigated the incidence of herpes zoster among health‐care workers and the general population in Taiwan to see whether such a protective effect exists among health‐care workers against herpes zoster. This nationwide population‐based retrospective cohort study was based on data obtained from the Taiwan National Health Insurance Database. In total, 7744 health‐care workers, including 168 dermatologists and pediatricians, and 695 188 general adults were recruited for the study. Health‐care workers in the age groups 20–29, 30–39 and 40–49 years were found to have a significant higher herpes zoster incidence compared to the general adults (P < 0.001, 0.011 and <0.001, respectively). Both logistic regression and Cox regression showed that dermatologists, pediatricians, and other medical professionals have a higher herpes zoster incidence than the general population (odds ratio [OR] = 1.36, 95% confidence interval [95% CI] = 0.63–2.90, hazards ratio [HR] = 1.35, 95% CI = 0.64–2.82 in dermatologist and pediatrician groups, and OR = 1.39, 95% CI = 1.23–1.58, HR = 1.38, 95% CI = 1.22–1.56 in other medical professionals). The incidence of herpes zoster is higher among health‐care workers and it can be clearly concluded that no protective effect against herpes zoster exists for health‐care workers in Taiwan. 相似文献
996.
Jing Che Wei-Wei Zhou Jian-Sheng Hu Fang Yan Theodore J. Papenfuss David B. Wake Ya-Ping Zhang 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(31):13765-13770
Asian frogs of the tribe Paini (Anura: Dicroglossidae) range across several first-order tectono-morphological domains of the Cenozoic Indo-Asian collision that include the Tibetan Plateau, the Himalayas, and Indochina. We show how the tectonic events induced by the Indo-Asian collision affected the regional biota and, in turn, how the geological history of the earth can be viewed from a biological perspective. Our analysis of a concatenated dataset comprising four nuclear gene sequences of Paini revealed two main radiations, corresponding to the genera Nanorana (I) and Quasipaa (II). Five distinct clades are recognized: Tibetan plateau clade (I-1), Himalaya clade (I-2), environs of Himalaya–Tibetan plateau clade (I-3), South China clade (II-1), and Indochina clade (II-2). This pattern of relationships highlights the significance of geography in shaping evolutionary history. Building on our molecular dating, ancestral region reconstruction, and distributional patterns, we hypothesize a distinct geographic and climatic transition in Asia beginning in the Oligocene and intensifying in the Miocene; this stimulated rapid diversification of Paini. Vicariance explains species formation among major lineages within Nanorana. Dispersal, in contrast, plays an important role among Quasipaa, with the southern Chinese taxa originating from Indochina. Our results support the tectonic hypothesis that an uplift in the Himalaya–Tibetan plateau region resulting from crustal thickening and lateral extrusion of Indochina occurred synchronously during the transition between Oligocene and Miocene in reaction to the Indo-Asian collision. The phylogenetic history of Paini illuminates critical aspects of the timing of geological events responsible for the current geography of Southeast Asia. 相似文献
997.
998.
目的通过检测铅中毒大鼠肝、肾功能及部分血液学指标,阐明铅暴露对发育期大鼠肝、肾功能及血液学指标的损伤作用,为铅中毒的毒性效应研究以及防治提供实验依据。方法大鼠醋酸铅饮水染毒建立模型,通过模型肝、肾功能及血液学指标的改变,探讨铅暴露对大鼠肝、肾功能的损伤作用。结果染铅大鼠血清天门冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)水平较对照组显著增高,差异有统计学意义(P<0.05);血清胆碱酯酶(CHE)水平较对照组显著降低,差异有统计学意义(P<0.05),提示肝细胞损伤;染铅大鼠血清尿素氮(BUN)、胱抑素C(CYS-C)水平较对照组显著增高,差异有统计学意义(P<0.05),提示肾小球率过滤及肾功能损伤;铅暴露大鼠红细胞、血红蛋白、血小板数量下降显著,差异有统计学意义(P<0.05),提示贫血及凝血机制障碍。结论慢性铅暴露可以引起生长发育期大鼠的肝、肾功能损伤及贫血的发生。 相似文献
999.
Raymond M. Welsh Jenny W. Che Michael A. Brehm Liisa K. Selin 《Immunological reviews》2010,235(1):244-266
Summary: Immune memory responses to previously encountered pathogens can sometimes alter the immune response to and the course of infection of an unrelated pathogen by a process known as heterologous immunity. This response can lead to enhanced or diminished protective immunity and altered immunopathology. Here, we discuss the nature of T-cell cross-reactivity and describe matrices of epitopes from different viruses eliciting cross-reactive CD8+ T-cell responses. We examine the parameters of heterologous immunity mediated by these cross-reactive T cells during viral infections in mice and humans. We show that heterologous immunity can disrupt T-cell memory pools, alter the complexity of the T-cell repertoire, change patterns of T-cell immunodominance, lead to the selection of viral epitope-escape variants, alter the pathogenesis of viral infections, and, by virtue of the private specificity of T-cell repertoires within individuals, contribute to dramatic variations in viral disease. We propose that heterologous immunity is an important factor in resistance to and variations of human viral infections and that issues of heterologous immunity should be considered in the design of vaccines. 相似文献
1000.
Trigeminal neurinomas are the second most common intracranial neurinomas next to the vestibular neurinomas. Eighty-four patients
with trigeminal neurinomas were treated between 2003 and 2007. There were 40 women and 44 men (mean age 43 years). The most
frequent symptoms were headache or numbness of the ipsilateral hemiface. There were 24 type A, nine type B, 45 type C, and
six type D tumors. Dextroscope virtual reality technology was used for preoperative planning in recent eight cases. Gross
total resection was achieved in 63 patients. We found that the major impediments to complete removal were adherent to the
brainstem and skull base vascular structure, the frontotemporal approach with zygomatic or orbitozygomatic osteotomy or subtemporal
approach could offer excellent exposure of the middle fossa and access to the posterior fossa, and Dextroscope virtual reality
technology was a very useful tool to identify surgical and anatomic nuances and enhance preoperative planning in trigeminal
neurinomas resection. 相似文献