首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   92篇
  免费   8篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   1篇
基础医学   18篇
临床医学   3篇
内科学   14篇
神经病学   5篇
特种医学   6篇
外科学   5篇
综合类   5篇
预防医学   20篇
眼科学   1篇
药学   6篇
中国医学   14篇
肿瘤学   3篇
  2024年   1篇
  2023年   2篇
  2022年   3篇
  2021年   4篇
  2020年   4篇
  2019年   4篇
  2018年   5篇
  2017年   4篇
  2016年   2篇
  2015年   8篇
  2014年   9篇
  2013年   5篇
  2012年   15篇
  2011年   4篇
  2010年   3篇
  2009年   4篇
  2008年   3篇
  2007年   4篇
  2006年   4篇
  2005年   2篇
  2004年   1篇
  2003年   5篇
  2001年   2篇
  2000年   1篇
  1991年   1篇
  1978年   2篇
排序方式: 共有102条查询结果,搜索用时 31 毫秒
1.
西北地区汉族人群HLA-A、-B、-DRB1基因座单倍型分析   总被引:3,自引:0,他引:3  
目的 分析西北地区汉族群体HLA-A、-B和-DRB1基因座等位基因频率和HIA-A-B、B-DRB1和A-B-DRB1单倍型,获得单倍型频率数据。方法 采用序列特异性寡核苷酸探针反向斑点杂交技术对西北地区62个家系和101个无关个体HLA-A、-B和-DRB1基因座进行基因分型,分析HLA单倍型。结果 在西北地区汉族人群中检出15个HLA-A等位基因,28个HLA-B等位基因,13个HLA-DRB1等位基因,A02、A11、A24、B13、B15、1340、DRB1*04、DRB1*07、DRB1*09和DRB1*15基因频率较高(〉10%),A02(0.3244)、B13(0.1200)和DRB1*15(0.1400)等位基因频率最高。分析得出HLA-A-B、B-DRB1、A-B-DRB1单倍型分别有122、147和278种,83种A-B-DRB1单倍型有至少两条以上相同的单倍型,占总单倍型数的18.44%(83/450)。A30-B13-DRB1*07、A02-B46-DRB1*09、A01-B37-DRB1*10、A24-B15-DRB*15、A02-B46-DRB1*08、A33-B58-DRB1*03是最常见的单倍型。结论 西北地区汉族群体HLA单倍型多态性较为丰富,等位基因频率和单倍型频率数据可用于骨髓移植供者的选择、法医学亲权鉴定以及人类学研究。  相似文献   
2.
We report an active surveillance study of the occurrence of specific antibodies to European Bat Lyssavirus Type 1 (EBLV-1) in bat species, scarcely studied hitherto, that share the same refuge. From 2004 to 2012, 406 sera were obtained from nine bat species. Blood samples were subjected to a modified fluorescent antibody virus neutralization test to determine the antibody titer. EBLV-1-neutralizing antibodies were detected in six of the nine species analyzed (Pipistrellus pipistrellus, P. kuhlii, Hypsugo savii, Plecotus austriacus, Eptesicus serotinus and Tadarida teniotis). Among all bats sampled, female seroprevalence (20.21%, 95% CI: 14.78%–26.57%) was not significantly higher than the seroprevalence in males (15.02%, 95% CI: 10.51%–20.54%). The results showed that the inter-annual variation in the number of seropositive bats in T. teniotis and P. austriacus showed a peak in 2007 (>70% of EBLV-1 prevalence). However, significant differences were observed in the temporal patterns of the seroprevalence modeling of T. teniotis and P. austriacus. The behavioral ecology of these species involved could explain the different annual fluctuations in EBLV-1 seroprevalence.  相似文献   
3.
We studied the role of European rabbits (Oryctolagus cuniculus) as a reservoir for Coxiella burnetii in the Iberian region. High individual and population seroprevalences observed in wild and farmed rabbits, evidence of systemic infections, and vaginal shedding support the reservoir role of the European rabbit for C. burnetii.  相似文献   
4.
In deer, most of the earlier investigations on pineal function examined the effects of artificial photoperiods or the administration of melatonin to manipulate reproduction. However, endogenous melatonin rhythms have not been studied in red deer. Thus, we monitored seasonal changes in plasma melatonin concentrations in 16 adult female Iberian red deer living in outdoor enclosures. Blood was sampled on the day of each seasonal change every 3-4 hr overnight and 1 hr before and after sunset and sunrise. In addition, in six of the previous hinds, blood sampling during the hour prior and after sunset and sunrise was collected every 20 min. Significant differences were found both in amplitude and duration of the nocturnal plasma melatonin profiles in the four seasonal changes (P < 0.01). The nocturnal mean level of melatonin, the duration of nocturnal secretion levels and maximal concentrations were significantly higher at the winter solstice than in summer solstice or equinoxes (P < 0.05). Moreover, the mean overnight concentrations were significantly higher at the spring equinox and winter solstice than during the summer solstice and autumn equinox (P < 0.05). A pronounced elevation from low levels was recorded 1 hr after sunset, remained elevated during the hours of darkness and declined to low levels 1 hr after dawn. Concentrations close to sunrise were higher than those near sunset at all changes of season (P < 0.05). These results show for the first time in red deer that the pineal gland of the adult female is highly responsive to both daily and seasonal changes in natural environmental illumination, although overnight levels lasted longer than the photoperiodic night is all cases, particularly at the winter solstice.  相似文献   
5.
A paralytic shellfish poisoning (PSP) episode developed in summer 2018 in the Rías Baixas (Galicia, NW Spain). The outbreak was associated with an unprecedentedly intense and long-lasting harmful algal bloom (HAB) (~one month) caused by the dinoflagellate Alexandrium minutum. Paralytic shellfish toxins (PSTs) were analyzed in extracts of 45 A. minutum strains isolated from the bloom by high-performance liquid chromatography with post-column oxidation and fluorescence detection (HPLC-PCOX-FLD). PSTs were also evaluated in tissues from marine fauna (invertebrates and fish) collected during the episode and in dolphin samples. The analysis of 45 A. minutum strains revealed a toxic profile including GTX1, GTX2, GTX3 and GTX4 toxins. With regard to the marine fauna samples, the highest PSTs levels were quantified in bivalve mollusks, but the toxins were also found in mullets, mackerels, starfish, squids and ascidians. This study reveals the potential accumulation of PSTs in marine invertebrates other than shellfish that could act as vectors in the trophic chain or pose a risk for human consumption. To our knowledge, this is the first time that PSTs are reported in ascidians and starfish from Spain. Moreover, it is the first time that evidence of PSTs in squids is described in Europe.  相似文献   
6.
The impact of carnivore parvovirus infection on wild populations is not yet understood; disease signs are mainly developed in pups and assessing the health of litters in wild carnivores has big limitations. This study aims to shed light on the virus dynamics among wild carnivores thanks to the analysis of 213 samples collected between 1994 and 2013 in wild ecosystems from Spain. We determined the presence of carnivore parvovirus DNA by real‐time PCR and sequenced the vp2 gen from 22 positive samples to characterize the strains and to perform phylogenetic analysis. The presence of carnivore parvovirus DNA was confirmed in 18% of the samples, with a higher prevalence detected in wolves (Canis lupus signatus, 70%). Fourteen sequences belonging to nine wolves, three Eurasian badgers (Meles meles), a common genet (Genetta genetta) and a European wildcat (Felis silvestris) were classified as canine parvovirus 2c (CPV‐2c); five sequences from three wolves, a red fox (Vulpes vulpes) and a stone marten (Martes foina) as CPV‐2b; and three sequences from a badger, a genet and a stone marten as feline parvovirus (FPV). This was the first report of a wildcat infected with a canine strain. Sequences described in this study were identical or very close related to others previously found in domestic carnivores from distant countries, suggesting that cross‐species transmission takes place and that the parvovirus epidemiology in Spain, as elsewhere, could be influenced by global factors.  相似文献   
7.
The COVID-19 pandemic, which began in Wuhan (Hubei, China), has been ongoing for about a year and a half. An unprecedented number of people around the world have been infected with SARS-CoV-2, the etiological agent of COVID-19. Despite the fact that the mortality rate for COVID-19 is relatively low, the total number of deaths has currently already reached more than three million and continues to increase due to high incidence. Since the beginning of the pandemic, a large number of sequences have been obtained and many genetic variants have been identified. Some of them bear significant mutations that affect biological properties of the virus. These genetic variants, currently Variants of Concern (VoC), include the so-called United Kingdom variant (20I/501Y), the Brazilian variant (20J/501Y.V3), and the South African variant (20H/501Y.V2). We describe here a novel SARS-CoV-2 variant with distinct spike protein mutations, first obtained at the end of January 2021 in northwest Russia. Therefore, it is necessary to pay attention to the dynamics of its spread among patients with COVID-19, as well as to study in detail its biological properties.  相似文献   
8.
目的 探讨半岛黄金微针射频联合欧美娜红光治疗腋臭的效果。方法 选取2021年4月-2023年3月 江门市新会区皮肤医院接受治疗的60例腋臭患者作为研究对象,随机将患者分为对照组与观察组,每组 30例。对照组采用小切口大汗腺腺体剥离术治疗,观察组采用半岛黄金微针射频联合欧美娜红光治疗,比 较两组腋部气味、腋下汗液分泌范围、临床疗效及并发症发生情况。结果 观察组治疗后腋部气味VAS评 分、腋下汗液分泌范围、治疗总有效率与对照组比较,差异无统计学意义(P>0.05);观察组并发症发生 率为3.33%,低于对照组的20.00%(P<0.05)。结论 针对腋臭患者,采用半岛黄金微针射频联合欧美娜红 光治疗可取得与手术相似的效果,可去除腋部气味,缩小腋下汗液分泌范围,降低并发症发生几率。  相似文献   
9.
目的:探讨新疆和田地区维吾尔族及汉族城乡居民西北燥证罹患情况及症状特点,为西北燥证防治研究提供可靠依据。方法:根据中医理论和现代流行病学方法设计调查量表,对和田地区农村和城市的维吾尔族和汉族居民实施抽样问卷调查,然后进行西北燥证计量辨证和统计学分析。结果:共完成1403例问卷调查,得出和田地区各调查点不同民族、不同性别、不同年龄和不同居住环境(城乡)居民的西北燥证罹患率分布、燥证症状原始积分及主要症状得分数据,和田维吾尔族居民燥证症状积分明显低于汉族(P〈O.05),维吾尔族居民燥证罹患者的症状较汉族罹患者为轻。其中,巴格其镇维吾尔族居民燥证罹患率最低,燥证症状积分最低,症状亦最轻。男性燥证罹患率低于女性,尤以农村维吾尔族居民最明显(P〈0.01)。城市居民燥证罹患率(37.96%)高于农村(31.12%)(P〈0.05)。结论:和田为西北燥证罹患率最高地区,同是和田地区居民,其燥证罹患情况又因民族、性别和居住环境不同而存在差别,其中巴格其镇居民燥证罹患情况最具特殊性,这将成为今后开展西北燥证防治研究的重要依据。  相似文献   
10.
An active biomonitoring experiment was performed using mussels collected at a clean site, Fier d'Ars, and transplanted to two locations, outside the harbor of La Rochelle and in the Baie de L'Aiguillon along the coast of Charentes (French Atlantic coast) beginning in April for several months. Mussels were collected in June and October. The cadmium, copper, and zinc concentrations of all resident and transplanted mussel samples and the polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations in some mussel samples and in the sediment samples were determined. Mussel response was evaluated for several biochemical biomarkers: concentrations of metallothionein, activities of glutathione S-transferase and acetylcholinesterase (AChE) and levels of thiobarbituric reactive substance (TBARS). The physiological status of the animals was assessed using the condition index. A principal component analysis performed with the chemical and biochemical results of the evaluations of the resident and transplanted mussels collected in June allowed them to be separated into three groups: resident mussels from la Rochelle with high metal and TBARS levels, resident mussels from Baie de L'Aiguillon with a very high condition index, and resident mussels from Fier d'Ars and transplanted mussels at La Rochelle and Baie de L'Aiguillon with low TBARS and AChE activities. Strong seasonal variation from June to October of all parameters was noted. Mussels transplanted to La Rochelle appeared to be the most "polluted" in their pollutant concentrations and biochemical responses; moreover, the La Rochelle site had the highest concentration of organics in sediments of all the sites. The choice of Fier d'Ars as a reference site may be questionable because some of the biomarker responses of the mussels were higher than expected there, although these pollutants in mussels and sediment were present at the lowest concentrations measured.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号