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1.
目的:对鲁西南地区男童包皮发育情况及父母对包皮环切接受情况进行调查研究。方法选取山东省枣庄、济宁以及菏泽等鲁西南地区的婴幼儿和中小学在校学生作为研究对象,将年龄介于0~3岁,4~6岁,7~10岁,11~14岁以及15~18岁研究对象分为5组,分别为第一到第五组,每组选取200名儿童调查其包皮发育情况,并分别对5组研究对象的家长做包皮环切术接受度的调查;其中包皮上翻程度分为Ⅰ度至Ⅶ度,家长接受情况分为接受、不接受和不清楚3种,并对结果进行分析。结果在5组研究对象中,随着年龄的增长其平均包皮长度逐渐增长( t=16.729,P=0.000<0.05)。在1000例研究对象中,有534例(53.4%)存在包茎,随着年龄的增长包茎发病逐渐减少(χ2=119.963,P=0.000<0.05);有182例(18.2%)存在包皮过长,随着年龄增长包皮过长发病也逐渐减少(χ2=44.054,P=0.000<0.05);有70例(7.0%)人存在包皮口狭窄,但发病与年龄无关(χ2=1.382,P=0.847>0.05)。家长对包皮环切接受率由低年龄儿童到高年龄逐渐增加(χ2=0.000,P=1.000>0.05),但接受率均少于30%。结论研究表明调查对象包皮过长以及包茎现象较为严重,但随着年龄的增长逐渐好转,包茎率逐渐降低,并且随着年龄的增长,家长对儿子进行包皮环切的接受度也逐渐增高,但总体而言对男童进行包皮环切术接受率较低。  相似文献   
2.
Tibet’s ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to ∼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This “Shangri-La”–like ecosystem experienced monsoon seasonality with a mean annual temperature of ∼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.

The Tibetan Plateau, once thought of as entirely the product of the India–Eurasia collision, is known to have had significant complex relief before the arrival of India early in the Paleogene (13). This large region, spanning ∼2.5 million km2, is an amalgam of tectonic terranes that impacted Asia long before India’s arrival (4, 5), with each accretion contributing orographic heterogeneity that likely impacted climate in complex ways. During the Paleogene, the Tibetan landscape comprised a high (>4 km) Gangdese mountain range along the southern margin of the Lhasa terrane (2), against which the Himalaya would later rise (6), and a Tanghula upland on the more northerly Qiangtang terrane (7). Separating the Lhasa and Qiangtang blocks is the east–west trending Banggong-Nujiang Suture (BNS), which today hosts several sedimentary basins (e.g., Bangor, Nyima, and Lunpola) where >4 km of Cenozoic sediments have accumulated (8). Although these sediments record the climatic and biotic evolution of central Tibet, their remoteness means fossil collections have been hitherto limited. Recently, we discovered a highly diverse fossil assemblage in the Bangor Basin. These fossils characterize a luxuriant seasonally wet and warm Shangri-La forest that once occupied a deep central Tibetan valley along the BNS, and provide a unique opportunity for understanding the evolutionary history of Asian biodiversity, as well as for quantifying the paleoenvironment of central Tibet.*Details of the topographic evolution of Tibet are still unclear despite decades of investigation (4, 5). Isotopic compositions of carbonates recovered from sediments in some parts of central Tibet have been interpreted in terms of high (>4 km) Paleogene elevations and aridity (9, 10), but those same successions have yielded isolated mammal (11), fish (12), plant (1318), and biomarker remains (19) more indicative of a low (≤3-km) humid environment, but how low is poorly quantified. Given the complex assembly of Tibet, it is difficult to explain how a plateau might have formed so early and then remained as a surface of low relief during subsequent compression from India (20). Recent evidence from a climate model-mediated interpretation of palm fossils constrains the BNS elevation to below 2.3 km in the Late Paleogene (16), but more precise paleoelevation estimates are required. Further fossil discoveries, especially from earlier in the BNS sedimentary records, would document better the evolution of the Tibetan biota, as well as informing our understanding of the elevation and climate in an area that now occupies the center of the Tibetan Plateau.Our work shows that the BNS hosted a diverse subtropical ecosystem at ∼47 Ma, and this means the area must have been both low and humid. The diversity of the fossil flora allows us to 1) document floristic links to other parts of the Northern Hemisphere, 2) characterize the prevailing paleoclimate, and 3) quantify the elevation at which the vegetation grew. We propose that the “high and dry” central Tibet inferred from some isotope paleoaltimetry (9, 10) reflects a “phantom” elevated paleosurface (20) because fractionation over the bounding mountains allowed only isotopically light moist air to enter the valley, giving a false indication of a high elevation (21).  相似文献   
3.
Enterovirus A71 (EV-A71) infection is known to cause hand, foot, and mouth disease (HFMD). Last year, an inactivated EV-A71 whole virus vaccine was used to prevent this disease in Yunnan, China. To obtain a viral genetic background for evaluating vaccine protection and monitor the adaptive evolution of the virus after the vaccination, a 5-year molecular epidemiology survey was performed before the vaccination. Twenty-six EV-A71 strains were separated from 561 stool specimens of patients with serious HFMD. The whole-genomic sequences of these strains were sequenced. Phylogenetic trees were constructed, and the mutation spectra were analyzed based on these viral sequences. There was no obvious mutation for the circular EV-A71 strains of the same year. Pathogenic EV-A71 strains may arise from a “subgroup” randomly each year. Whole-genomic analyses showed that a hotspot nonsynonymous substitution potentially affecting the immunogenicity of vaccines was found in the 2A gene, but not in genes of the viral capsid proteins, and the genetic diversity of whole viral genomes associated with the incidence of HFMD. Therefore, it will be valuable to monitor the genome-wide changes of EV-A71 to detect the adaptive mutations affecting immunogenicity or perform investigations using genetic diversity as a parameter.  相似文献   
4.
目的:研究中国汉族人与日本人的头面部形态学差异。方法:按照《人体测量方法》的规定,于2009年8月测量了山西汉族成人体质数据,于2010年10月测量了四川汉族成人体质数据。将汉族和日本人体质资料进行了比较。结果:与日本人相比,汉族人身高较低,体质量略重,头的长、宽、高和头围较小,口较小,面部和鼻较高。结论:主成分分析结果表明,中国华北华中、西南汉族人体质较为接近,与东亚类型的日本人体质差距明显,主要表现在汉族人头的宽度、围度、高度、长度及身高小于日本人。  相似文献   
5.
From the deglacial period to the mid-Holocene, North Africa was characterized by much wetter conditions than today. The broad timing of this period, termed the African Humid Period, is well known. However, the rapidity of the onset and termination of the African Humid Period are contested, with strong evidence for both abrupt and gradual change. We use optically stimulated luminescence dating of dunes, shorelines, and fluviolacustrine deposits to reconstruct the fluctuations of Lake Mega-Chad, which was the largest pluvial lake in Africa. Humid conditions first occur at ∼15 ka, and by 11.5 ka, Lake Mega-Chad had reached a highstand, which persisted until 5.0 ka. Lake levels fell rapidly at ∼5 ka, indicating abrupt aridification across the entire Lake Mega-Chad Basin. This record provides strong terrestrial evidence that the African Humid Period ended abruptly, supporting the hypothesis that the African monsoon responds to insolation forcing in a markedly nonlinear manner. In addition, Lake Mega-Chad exerts strong control on global biogeochemical cycles because the northern (Bodélé) basin is currently the world’s greatest single dust source and possibly an important source of limiting nutrients for both the Amazon Basin and equatorial Atlantic. However, we demonstrate that the final desiccation of the Bodélé Basin occurred around 1 ka. Consequently, the present-day mode and scale of dust production from the Bodélé Basin cannot have occurred before 1 ka, suggesting that its role in fertilizing marine and terrestrial ecosystems is either overstated or geologically recent.The West African monsoon (WAM) is key to our understanding of the African climate system and the impacts of future climate change upon its population. Climatically, the WAM is a major component of the global monsoon belt, which regulates moisture availability in the low latitudes and is sensitive to climate dynamics in both the high latitudes and the tropics. From a human perspective, the WAM represents the dominant control upon agricultural productivity in a densely populated region that is heavily reliant on subsistence agriculture (1). The broad pattern of WAM dynamics since the Last Glacial Maximum (LGM) is well known, with initially arid conditions being replaced by a more humid phase, sometimes termed the African Humid Period (AHP), which lasted from the deglacial period to the mid-Holocene. However, paleoclimate proxy data from North Africa and adjacent areas of the Atlantic provide contrasting evidence for the rate and timing of these changes, leading to uncertainty over the controls upon WAM dynamics.  相似文献   
6.
目的:探讨中国西南地区的牙源性肿瘤发病情况及临床病理特点,并与其它地区牙源性肿瘤流行特点进行对比分析,为牙源性肿瘤风险群体、临床诊断以及牙源性肿瘤相关研究提供依据。方法:回顾性分析2005年1月~2019年4月期间在昆明医科大学附属口腔医院和云南省第一人民医院就诊的494例牙源性肿瘤患者的临床病理资料,对比中国西南地区与其它地区流行病学状况的区别。结果:中国西南地区494例牙源性肿瘤患者中,男性271例(54.9%),女性223例(45.1%),男女性别比为1.22∶1。牙源性肿瘤平均年龄(32.99±15.96)岁。良性484例(98%),恶性10例(2%)。其中成釉细胞瘤多见,占403例(81.6%),其次是牙瘤34例(6.9%)。牙源性肿瘤发生于下颌骨与上颌骨之比为5.1∶1,413例(83.6%)发于下颌骨。结论:中国西南地区牙源性肿瘤以成釉细胞瘤最多见,多发于年轻男性下颌骨。中国西南地区牙源性肿瘤和成釉细胞瘤发生率大约分别为0.98和0.80人/100万人。  相似文献   
7.
Acute viral respiratory infections (AVRI) are a leading cause of morbidity and mortality among all age groups globally. Except for Influenza virus and Respiratory Syncytial virus, mostly viral aetiology of AVRI remains undiagnosed. Lately, human coronaviruses (HCoVs) have emerged as an important aetiology of AVRI. A laboratory based retrospective cross sectional study was conducted in which respiratory samples (throat swabs) of patients (n = 864), with Influenza negative SARI, of all age groups between Jan 2011–Dec 2012 were tested for HCoVs including MERS‐CoV using Conventional and real time PCR assays. The prevalence of HCoV among SARI cases was 1.04% (9/864) [95% CI: 0.36–1.72]. Of these four (44.44%) were identified as HCoV OC43, three (33.33%) as HCoV NL63 and two (22.22%) as HCoV 229E. No HCoV HKU1 was detected. The samples were also negative for SARS‐CoV and MERS‐CoV. The results of this study documents low prevalence of human coronaviruses in SARI cases in south western India and the absence of highly pathogenic human coronaviruses. As the study included only SARI cases the prevalence reported could be an under estimate when it is extrapolated to community. J. Med. Virol. 88:163–165, 2016. © 2015 Wiley Periodicals, Inc.
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8.
A high-resolution multiproxy record, including pollen, foraminifera, and alkenone paleothermometry, obtained from a single core (DG9603) from the Okinawa Trough, East China Sea (ECS), provided unambiguous evidence for asynchronous climate change between the land and ocean over the past 40 ka. On land, the deglacial stage was characterized by rapid warming, as reflected by paleovegetation, and it began ca. 15 kaBP, consistent with the timing of the last deglacial warming in Greenland. However, sea surface temperature estimates from foraminifera and alkenone paleothermometry increased around 20–19 kaBP, as in the Western Pacific Warm Pool (WPWP). Sea surface temperatures in the Okinawa Trough were influenced mainly by heat transport from the tropical western Pacific Ocean by the Kuroshio Current, but the epicontinental vegetation of the ECS was influenced by atmospheric circulation linked to the northern high-latitude climate. Asynchronous terrestrial and marine signals of the last deglacial warming in East Asia were thus clearly related to ocean currents and atmospheric circulation. We argue that (i) early warming seawater of the WPWP, driven by low-latitude insolation and trade winds, moved northward via the Kuroshio Current and triggered marine warming along the ECS around 20–19 kaBP similar to that in the WPWP, and (ii) an almost complete shutdown of the Atlantic Meridional Overturning Circulation ca. 18–15 kaBP was associated with cold Heinrich stadial-1 and delayed terrestrial warming during the last deglacial warming until ca. 15 kaBP at northern high latitudes, and hence in East Asia. Terrestrial deglacial warming therefore lagged behind marine changes by ca. 3–4 ka.  相似文献   
9.
10.
军队医院是我军卫勤保障的主体力量,直接影响我军战斗力保障力的生成提高和有效发挥,随着现代战争作战方式的转变,军队卫勤保障模式也必须顺势而变.本文从本院野战医疗所参加西南边境地区实兵实弹演习,实施精准卫勤保障经验出发,阐述实施精准卫勤保障的必要性、具体做法和建议.  相似文献   
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