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101.
李法军 《人类学学报》2016,35(2):283-299
一直以来,有关人类牙齿磨耗的研究主要集中在年龄判定和生业方式比较方面。然而,很多研究因样本人群来源复杂、忽视个体牙齿磨耗的特殊性及缺乏足够的个人信息,很难进一步解释其牙齿磨耗特点的成因。本文基于对当代水族男性牙齿磨耗的记录和相关信息,通过梳理该人群牙齿磨耗的一般特点和特殊磨耗形式,探讨了有关影响该人群牙齿磨耗的可能因素。笔者发现,总体来说,该人群的牙齿磨耗较轻,牙齿磨耗水平与其年龄分布呈正相关关系,符合人类牙齿面随年龄增长而发生退行性生理磨耗的规律。牙齿磨耗等级在不同年龄中呈镶嵌式分布,某些个体存在越位磨耗现象。从本文的结果看,这些现象的产生除了退行性生理磨耗的原因外,还可能与口腔健康状况、饮食结构和少餐习惯等因素密切相关。  相似文献   
102.
羧甲基壳聚糖对口腔重要厌氧菌的抑菌性能评价   总被引:9,自引:0,他引:9  
目的 :评价羧甲基壳聚糖对口腔重要厌氧菌的抑菌性能。方法 :选择与口腔疾病密切相关的厌氧菌 11株 ,采用梯度稀释法测定羧甲基壳聚糖的最低抑菌浓度 (MIC)。结果 :羧甲基壳聚糖对牙龈卟啉菌、放线共生放线菌、中间普氏菌、牙龈嗜二氧化碳纤维菌、黄褐嗜二氧化碳纤维菌、产黑色素普氏菌、白色念珠菌、牙髓卟啉菌、小齿普氏菌、变形链球菌、远缘链球菌、粘性放线菌的 MIC分别为 2 0 ,10 ,5,80 ,2 0 ,>80 ,2 0 ,5,2 0 ,10 ,60 ,40 mg/ml。结论 :羧甲基壳聚糖对多数与口腔疾病密切相关的厌氧菌有一定抑制作用 ,而对产黑色素普氏菌的抑菌性不明显  相似文献   
103.
We have conducted a study to analyze monitoring of the cold chain of 674 OPV field samples collected at four different levels of vaccine distribution viz., immunization clinics, district stores, hospitals and Primary Health Centers (PHC) from states of Uttar Pradesh, Madhya Pradesh, and Delhi. The study design included: collection and scoring of vaccine vial monitor (VVM) status of the samples and testing for total oral polio virus concentration (TOPV) by standard WHO protocol. Ten samples each were exposed to 25 degrees C and 37 degrees C, and 10 samples as controls were kept at -20 degrees C. VVM were scored daily till they attained grade 4 and each sample was subsequently subjected to potency testing for individual polio serotypes 1, 2 and 3, and TOPV.Of the 674 samples tested it was observed that: samples from immunization clinics and district stores had an acceptable VVM score of grade 1 and 2; however the probable risk that a sub potent vaccine could have been administered was 2.15%. In 2.5% samples received from district stores vaccine had a VVM score of grade 3 (i.e., discard point), although vaccine when tested was found to be potent (i.e., leading to the vaccine wastage). With exposure to higher temperatures, VVM changed score to grade 2 and 3 when the vaccine was kept at 25 degrees C/37 degrees C, and the titres of individual serotypes 1, 2 and 3 and TOPV were beyond the acceptable limits.Important observations at the different levels of vaccine distribution network and correlation of VVM and potency status of OPV are discussed in the paper which will be of help to the EPI program managers at different transit levels.  相似文献   
104.
This paper provides ethnographic and historical evidence for the existence, in time and space, of a network of well-established trails connecting most Inuit settlements and significant places across the Canadian Arctic. The geographic and environmental knowledge relating to trails (and place names associated with the trails) has been orally transmitted through many generations of Inuit. I use historical documents, ethnographic research, and new geographic tools such as GPS, GIS and Google Earth, to show the geographic extent of the network and its historical continuity. I particularly draw on a trip following Inuit along a traditional trail connecting the communities of Iglulik and Naujaat (Repulse Bay). Inuit have made systematic use of the Arctic environment as a whole and trails are, and have been, significant channels of communication and exchange across the Arctic. There are some types of oral history and knowledge that can be accurately transmitted through generations, and I propose that some aspects of Inuit culture are better understood in terms of moving as a way of living.
Claudio AportaEmail:
  相似文献   
105.
Candida albicans and C. tropicalis obtained from whole saliva of patients presenting signs of oral candidosis were assayed for quantification of colony forming units, exoenzyme activity (phospholipase and proteinase) and antifungal drug sensitivity (amphotericin B, fluconazole and itraconazole) by the reference method of the Clinical and Laboratory Standards Institute. The number of colony forming units per milliliter varied according to the Candida species involved and whether a single or mixed infection was present. Proteinase activity was observed in both Calbicans and Ctropicalis, but phospholipase activity was noted only in Calbicans. In vitro resistance to antifungals was verified in both species, but Ctropicalis appears to be more resistant to the tested antifungals than Calbicans.  相似文献   
106.
K88 (F4) fimbrial adhesin, FaeG, was expressed extracellularly in Lactococcus lactis using a nisin-controlled gene expression system. The antibody response and protective efficacy of the recombinant bacteria (L. lactis [spNZ8048-faeG]) against live enterotoxigenic E. coli (ETEC) C83549 challenge were evaluated in ICR mice. Mice vaccinated with L. lactis [spNZ8048-faeG] had a significantly increased antigen-specific IgG level in the serum and decreased mortality rate (P < 0.05) compared with the control. This indicates that oral immunization of L. lactis [spNZ8048-faeG] can induce an immune-response protection upon challenge with live ETEC in ICR mice. An erratum to this article can be found at  相似文献   
107.
In our earlier studies, we constructed a hybrid strain of Shigella dysenteriae type 1 by introducing a plasmid vector pPR 1347. After introduction of a lipopolysaccharide (LPS) biosynthesis gene, virulent Shigella dysenteriae type 1 strain became avirulent. In our present study, we have evaluated the immune response and protective efficacy of avirulent live transconjugant Shigella hybrid (LTSH) strain against wild type Shigella dysenteriae type 1, after four doses of oral (rabbit) and intranasal (mouse) immunizations. Serum IgG titers showed exponential increase during immunization and peaking on the 28th day and remained at that level till the 35th day in both the rabbit and the mouse models. When tested, serum IgG titers persisted for 63 days in mice and relatively high for 150 days in case of rabbits. Protection studies showed 100% protection against the challenge with wild type Shigella dysenteriae type 1 strain in rabbits and 80% protection in mice. Our results suggested that the LTSH strain could be a useful vaccine candidate strain in the future.  相似文献   
108.
口腔鳞癌中D2-40表达的特点及临床意义   总被引:1,自引:0,他引:1  
目的探讨口腔鳞癌组织中淋巴管分布、密度及其与临床病理因素之间的关系。方法应用免疫组化SP法检测口腔癌D2-40的表达情况,计数淋巴管密度(lymphatic vessel density,LVD),分析其与临床病理特征间的关系。结果口腔鳞癌中的淋巴管形态及分布在不同区域具有异质性。与肿瘤中心(肿瘤实质)及癌旁正常组织比较,肿瘤边缘区(肿瘤间质)的淋巴管LVD为(11.09±2.958),显著高于肿瘤中心(5.81±1.334)及癌旁正常组织(4.96±1.716),且形态多呈扩张状态。结论口腔鳞癌中的淋巴管主要位于肿瘤边缘区,肿瘤边缘区LVD与淋巴结转移状态相关,检测口腔癌边缘区的LVD对预测是否发生淋巴结转移可能具有重要意义。  相似文献   
109.
Cereal crops such as maize and rice are considered attractive for vaccine production and oral delivery. Here, we evaluated the rice Oryza sativa for production of As16—an antigen protective against the roundworm Ascaris suum. The antigen was produced as a chimeric protein fused with cholera toxin B subunit (CTB), and its expression level in the endosperm reached 50 μg/g seed. Feeding the transgenic (Tg) rice seeds to mice elicited an As16-specific serum antibody response when administered in combination with cholera toxin (CT) as the mucosal adjuvant. Although omitting the adjuvant from the vaccine formulation resulted in failure to develop the specific immune response, subcutaneous booster immunization with bacterially expressed As16 induced the antibody response, indicating priming capability of the Tg rice. Tg rice/CT-fed mice orally administered A. suum eggs had a lower lung worm burden than control mice. This suggests that the rice-delivered antigen functions as a prophylactic edible vaccine for controlling parasitic infection in animals.  相似文献   
110.
用免疫不育疫苗控制有害动物的数量成为动物种群数量控制的一个有效措施,对于大多数动物来说.口服饵料发送系统是最好的选择。但是口服疫苗容易产生耐受,且生物利用度低,利用多聚物包裹口服疫苗是一种打破口服耐受.提高其生物利用度的新途径。本文以纳米乳剂作为草原兔尾鼠卵透明带3(Lugurus zone pellucida 3,LZP3)DNA疫苗的发送载体,探讨通过口服途径增强小鼠的免疫效果和抗生育率。用纳米乳剂包裹lzp3 DNA疫苗后,采用强阴离子交换色谱法测定纳米乳剂的包封率.将制备好的质粒纳米乳剂lzp3 DNA疫苗通过口服饵料免疫小鼠,检测到免疫后小鼠的体内产生了特异性的抗LZP3的IgG和IgA。对免疫后小鼠进行抗生育实验,分析生育后免疫小鼠的卵巢病理切片。研究结果表明,用质粒纳米乳剂如p3DNA疫苗通过口服途径免疫.在小鼠的血清和粘液中检测到了特异性的抗LZP3的IgG和IgA,同时也产生了相应的抗生育作用.表明纳米乳剂作为口服不育疫苗的发送载体是可行的,为草原兔尾鼠鼠害的防治提供了理论基础.  相似文献   
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