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   102篇
  免费   1篇
  2023年   1篇
  2021年   2篇
  2020年   2篇
  2019年   3篇
  2018年   1篇
  2016年   3篇
  2015年   3篇
  2014年   5篇
  2013年   6篇
  2012年   5篇
  2011年   10篇
  2010年   6篇
  2009年   4篇
  2008年   8篇
  2007年   5篇
  2006年   5篇
  2005年   3篇
  2004年   3篇
  2003年   4篇
  2002年   4篇
  2001年   7篇
  2000年   3篇
  1999年   3篇
  1996年   1篇
  1992年   1篇
  1991年   1篇
  1988年   1篇
  1984年   1篇
  1977年   2篇
排序方式: 共有103条查询结果,搜索用时 31 毫秒
61.
Basic causes of poor state of nutrition and infections in developing countries are poverty, low level of hygienic conditions and little access to preventive and health care. Central India is known for its high rate of population growth and mortality, which persisted over time along with a low level of social, economic and infrastructure development. In the present study the body mass index (BMI) of 31 populations residing in 38 districts of Central India (comprising the States of Madhya Pradesh and Chhattisgarh) is assessed. Anthropometric data collected by the Anthropological Survey of India were utilized in this context. The mean body mass index values of the populations of total backward and non-backward districts are found to be lower than that of well-to-do individuals of India (Bharati 1989, Khongsdier 1997, Reddy 1998), but it is not as low as that found among the South Indian populations (Ferro-Luzzi et al. 1992). In the present investigation, it is also found that the majority of the backward districts fall in the category of different grade of chronic energy deficiency (CED), while in the non-backward districts a considerably less number of districts follows this trend. A better level of the nutritional status among the populations of the non-backward districts corroborates the findings of the Ministry of Health and Family Welfare (NFHS 1992). It reveals that the apparently healthy individuals with CED grade I in the present study may be thin but physically active and healthy. The present study, however, narrates further intensive investigations in these populations, because the BMI as a measure of the CED should incorporate the aspects like morbidity and health status of a population.  相似文献   
62.
Morphometric characters of the adult males of the Tai-Phake and the nature and extent of morphometric variation among five neighboring mongoloid groups of Assam have been examined in the present study. For the sake of investigation 12 anthropometric measurements have been taken and five indices have been calculated. In order to obtain the distance values size, shape and biological distance are calculated. It revels that the Tai-Phake maintains a far distance with other five neighboring groups (Ahom, Deuri, Chutia, Mishing and Moran). The Ahom also maintain far distance with other five groups. While, the Mishing and Moran, and Deuri and Chutia maintain close distance among themselves.  相似文献   
63.
Drought is one of the most important factors limiting chickpea production in arid and semi-arid regions. There is little information regarding genotypic variation for drought tolerance in chickpea cultivars. Screening for drought tolerance is very important. It is essential to identify the physiological mechanisms of drought tolerance to complete conventional breeding program. Glasshouse experiment was carried out to study the genotypic variation among 11 chickpea (Cicer arietinum L.) cultivars. Plants were grown either under optimum conditions or drought stress was implemented at pre-or post-anthesis stages. The drought susceptibility index (DSI) was used as the measure of drought tolerance. Relationships between DSI and excised-leaf water loss (RWL), relative water content (RWC), membrane permeability, ascorbic acid, proline, and chlorophyll contents, lipid peroxidation, and hydrogen peroxide concentrations were determined in order to find out whether these physiological parameters could be used as the genotypic selection criteria for drought tolerance. The results of this study indicated that there was a wide variation in tolerance to drought stress among the chickpea cultivars, which could be exploited in breeding new chickpea cultivars with high drought tolerance. The results also demonstrated that drought-tolerant cultivars had a higher RWC, ascorbic acid and proline concentrations, but lower RWL and membrane permeability in comparison to drought-sensitive cultivars. The significant and a well defined relationships between DSI and RWC, RWL, ascorbic acid, proline, and membrane permeability were found. It was concluded that these parameters could be instrumental in predicting the drought tolerance of chickpea cultivars. This text was submitted by the authors in English.  相似文献   
64.
The active site architecture of Leishmania major peroxidase (LmP) is very similar with both cytochrome c peroxidase and ascorbate peroxidase. We utilized point mutagenesis to investigate if the conserved proximal methionine residues (Met248 and Met249) in LmP help in controlling catalysis. Steady-state kinetics of methionine mutants shows that ferrocytochrome c oxidation is <2% of wild type levels without affecting the second order rate constant of first phase of Compound I formation, while the activity toward a small molecule substrate, guaiacol or iodide, increases. Our diode array stopped-flow spectral studies show that the porphyrin π-cation radical of Compound I in mutant LmP is more stable than wild type enzyme. These results suggest that the electronegative sulfur atoms of the proximal pocket are critical factors for controlling the location of a stable Compound I radical in heme peroxidases and are important in the oxidation of ferrocytochrome c.  相似文献   
65.
Blood feeding is an integral process required for physiological functions and propagation of the malaria vector Anopheles. During blood feeding, presence of the malaria parasite, Plasmodium in the blood induces several host effector molecules including microRNAs which play important roles in the development and maturation of the parasite within the mosquito. The present study was undertaken to elucidate the dynamic expression of miRNAs during gonotrophic cycle and parasite development in Anopheles stephensi. Using next generation sequencing technology, we identified 126 miRNAs of which 17 were novel miRNAs. The miRNAs were further validated by northern hybridization and cloning. Blood feeding and parasitized blood feeding in the mosquitoes revealed regulation of 13 and 16 miRNAs respectively. Expression profiling of these miRNAs revealed that significant miRNAs were down-regulated upon parasitized blood feeding with a repertoire of miRNAs showing stage specific up-regulation. Expression profiles of significantly modulated miRNAs were further validated by real time PCR. Target prediction of regulated miRNAs revealed overlapping targeting by different miRNAs. These targets included several metabolic pathways including metabolic, redox homeostasis and protein processing machinery components. Our analysis revealed tight regulation of specific miRNAs post blood feeding and parasite infection in An. stephensi. Such regulated expression suggests possible role of these miRNAs during gonotrophic cycle in mosquito. Another set of miRNAs were also significantly regulated at 42 h and 5 days post infection indicating parasite stage-specific role of host miRNAs. This study will result in better understanding of the role of miRNAs during gonotrophic cycle and parasite development in mosquito and can probably facilitate in devising novel malaria control strategies at vector level.  相似文献   
66.
Multilocus variable number tandem repeat analysis (MLVA) provides microbiological support for investigations of clusters of cases of infection with Shiga toxin-producing E. coli (STEC) O157. All confirmed STEC O157 isolated in England and submitted to the Gastrointestinal Bacteria Reference Unit (GBRU) during a six month period were typed using MLVA, with the aim of assessing the impact of this approach on epidemiological investigations. Of 539 cases investigated, 341 (76%) had unique (>2 single locus variants) MLVA profiles, 12% of profiles occurred more than once due to known household transmission and 12% of profiles occurred as part of 41 clusters, 21 of which were previously identified through routine public health investigation of cases. The remaining 20 clusters were not previously detected and STEC enhanced surveillance data for associated cases were retrospectively reviewed for epidemiological links including shared exposures, geography and/or time. Additional evidence of a link between cases was found in twelve clusters. Compared to phage typing, the number of sporadic cases was reduced from 69% to 41% and the diversity index for MLVA was 0.996 versus 0.782 for phage typing. Using MLVA generates more data on the spatial and temporal dispersion of cases, better defining the epidemiology of STEC infection than phage typing. The increased detection of clusters through MLVA typing highlights the challenges to health protection practices, providing a forerunner to the advent of whole genome sequencing as a diagnostic tool.  相似文献   
67.
BackgroundWe report a widespread foodborne outbreak of Cryptosporidium parvum in England and Scotland in May 2012. Cases were more common in female adults, and had no history of foreign travel. Over 300 excess cases were identified during the period of the outbreak. Speciation and microbiological typing revealed the outbreak strain to be C. parvum gp60 subtype IIaA15G2R1.MethodsHypothesis generation questionnaires were administered and an unmatched case control study was undertaken to test the hypotheses raised. Cases and controls were interviewed by telephone. Controls were selected using sequential digit dialling. Information was gathered on demographics, foods consumed and retailers where foods were purchased.ResultsSeventy-four laboratory confirmed cases and 74 controls were included in analyses. Infection was found to be strongly associated with the consumption of pre-cut mixed salad leaves sold by a single retailer. This is the largest documented outbreak of cryptosporidiosis attributed to a food vehicle.  相似文献   
68.

Background  

The details of interaction in a complex between potent antagonists such as long chain α-neurotoxins and α-conotoxins with nicotinic acetylcholine receptor (nAChR), and conformational changes induced by these antagonists, are not yet clear.  相似文献   
69.
Changes in polypeptides pattern of haemolymph, midgut, ovary and salivary glands of female mosquito A. stephensi were studied when fed upon anti-mosquito haemolymph antibodies. The expression of almost all polypeptides was reduced in haemolymph and ovary of the immune fed mosquitoes as compared to control. However, there was no significant difference in case of midgut and salivary glands. Seven polypeptides 100, 90, 84, 80, 62, 19 and 12.5 kDa were absent in haemolymph and five 92, 90, 80, 60 and 55 kDa were absent in ovaries. Changes in the polypeptide pattern have been correlated with the fecundity reduction due to immunized blood feeding.  相似文献   
70.
In the present study an attempt has been made to examine the morphometric characteristics of the adult males of the Thinbu-pa and the nature and extent of morphometric variation among four neighbouring Monpa groups of Arunachal Pradesh (India), namely the Panchen-pa, Dirang Monpa, Tawang Monpa and Kalaktang Monpa. For the sake of investigation altogether 14 anthropometric measurements (11 pertaining to head and face and 3 on the body as a whole) have been taken and 5 indices have been calculated. To obtain the distance values the methods of Penrose (1947, 1954) and El-Najjar (1978) have been followed. It is observed that the Thingbu-pa maintain far distance with the four neighbouring Monpa groups as well as the Panchen-pa also maintain far distance with the other four groups, while the Dirang Monpa, Tawang Monpa and Kalaktang Monpa maintain close distance among each other.  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