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71.
New advances in Internet technologies and computer modeling provide opportunities for collaborative systems to support research and development in the field of industrial ecology. In particular, new information technologies such as semantic search engines based on ontologies could help researchers to link fragments of knowledge generated at research centers from around the world. Using a storyline of four imaginary researchers who hope to find collaborators in order to develop their research findings, we illustrate two levels of a four-level architecture for an Internet-based knowledge integration and collaboration environment for integrated environmental assessment. The foundation of the proposed architecture is a belief that computational models are an effective medium for conveying expert knowledge of various phenomena. Drawing from this premise, the first level of the architecture stands on a base of computational models that in some way represent the expert knowledge of the model builder. At the second level, we provide markup and interface definition tools to describe the type of knowledge contained in each model, together with the types of information services that can be provided.
The results of research at these two levels of an Internet-based knowledge integration environment for integrated environmental assessment in industrial ecology are presented in this article. Our work on the third level of model searching and matching and the fourth level of parametric model integration and solving will be presented in subsequent articles.  相似文献   
72.

Background

The number of morbidly obese patients undergoing bariatric surgery (BS) has increased dramatically in recent years. Therefore, monitoring food intake and its consequences in terms of nutritional status is necessary to prevent nutritional deficiencies. The aim of this study was to analyze the effect of food restriction on nutritional parameters in the short-term (≤3 months) period after BS in morbid obesity.

Method

In a prospective study, we followed 22 obese women who underwent Roux-en-Y gastric bypass (GBP) or adjustable gastric banding (AGB) at baseline (T0) and 1 (T1) and 3 (T3) months after surgery. We evaluated food intake, nutrient adequacy and serum concentrations of vitamins and minerals known to be at risk for deficiency following BS.

Results

Before surgery, we observed suboptimal food intakes, leading to a risk of micronutrient deficiencies. Serum analysis confirmed nutritional deficiencies for iron and thiamine for 27 and 23% of the patients, respectively. The drastic energy and food reduction seen in the short term led to very low probabilities of adequacy for nutrients equivalent across both surgeries. Serum analysis demonstrated a continuous decrease in prealbumin during the follow-up, indicating mild protein depletion in 21 and 57% of GBP patients and 50 and 63% of AGB patients, respectively, at T1 and T3. Regarding vitamins and minerals, systematic supplementation after GBP prevented most nutritional deficiencies. By contrast, AGB patients, for whom there is no systematic supplementation, developed such deficiencies.

Conclusions

Our results suggest that cautious monitoring of protein intake after BS is mandatory. Furthermore, AGB patients might also benefit from systematic multivitamin and mineral supplementation at least in the short term.  相似文献   
73.
The contribution of glutamine, glucose, ketone bodies and fatty acids to the oxidative energy metabolism of human diploid fibroblasts was studied. The rate of glutamine oxidation by fibroblasts was 98 nmol/h per mg cell protein compared to 2 nmol/h per mg cell protein or less for glucose, acetoacetate, d-3-hydroxybutyrate, octanoic acid and palmitic acid. Glucose inhibited glutamine oxidation by 85%, while the other substrates had no effect. Therefore, these cells meet their energy requirement almost solely by anaerobic glycolysis and glutamine oxidation.  相似文献   
74.
The word tradition has a very specific meaning in linguistics: the passing down of a text, which may have been completed or corrected by different copyists at different times, when the concept of authorship was not the same as it is today. When reading an ancient text the word tradition must be in the reader's mind. To discuss one of the problems an ancient text poses to its modern readers, this work deals with one of the first printed medical texts in Portuguese, the Regimento proueytoso contra ha pestenen?a, and draws a parallel between it and two related texts, A moche profitable treatise against the pestilence, and the Recopila?am das cousas que conuem guardar se no modo de preseruar à Cidade de Lixboa E os s?os, & curar os que esteuerem enfermos de Peste. The problems which arise out of the textual structure of those books show how difficult is to establish a tradition of another type, the medical tradition. The linguistic study of the innumerable medieval plague treatises may throw light on the continuities and on the disruptions of the so-called hippocratic-galenical medical tradition.  相似文献   
75.
76.

Background

Malaria immunity is commonly believed to wane in the absence of Plasmodium falciparum exposure, based on limited epidemiological data and short-lived antibody responses in some longitudinal studies in endemic areas.

Methods

A cross-sectional study was conducted among sub-Saharan African adults residing in Spain for 1 up to 38 years (immigrants) with clinical malaria (n=55) or without malaria (n=37), naïve adults (travelers) with a first clinical malaria episode (n=20) and life-long malaria exposed adults from Mozambique (semi-immune adults) without malaria (n=27) or with clinical malaria (n=50). Blood samples were collected and IgG levels against the erythrocytic antigens AMA-1 and MSP-142 (3D7 and FVO strains), EBA-175 and DBL-α were determined by Luminex. IgG levels against antigens on the surface of infected erythrocytes (IEs) were measured by flow cytometry.

Results

Immigrants without malaria had lower IgG levels than healthy semi-immune adults regardless of the antigen tested (P≤0.026), but no correlation was found between IgG levels and time since migration. Upon reinfection, immigrants with malaria had higher levels of IgG against all antigens than immigrants without malaria. However, the magnitude of the response compared to semi-immune adults with malaria depended on the antigen tested. Thus, immigrants had higher IgG levels against AMA-1 and MSP-142 (P≤0.015), similar levels against EBA-175 and DBL-α, and lower levels against IEs (P≤0.016). Immigrants had higher IgG levels against all antigens tested compared to travelers (P≤0.001), both with malaria.

Conclusions

Upon cessation of malaria exposure, IgG responses to malaria-specific antigens were maintained to a large extent, although the conservation and the magnitude of the recall response depended on the nature of the antigen. Studies on immigrant populations can shed light on the factors that determine the duration of malaria specific antibody responses and its effect on protection, with important implications for future vaccine design and public health control measures.  相似文献   
77.
78.
Background and objectiveOlder adults are at increased risk of violence. In order to prevent this, it is necessary to identify associated risk factors. The objective of the present study was to determine the association between violence and various socio-demographic factors (age, gender, ethnic group, level of education, and place of residence) in older adults.Material and methodsCross-sectional study that included participants from the SABE-Ecuador study, who were selected through probabilistic sampling and came from all over the national territory. Data were analysed with R using ordinal logistic regression models.ResultsSample included 4321 older adults, women (52%) and men (48%), with a mean age of 72 years (SD 8). Having suffered violence was reported in 21.3% (n = 922) of older adults. It was observed that the odds of suffering violence was lower in men than in women (OR = 0.753, p< .001), decreased as age increased (OR = 0.989, p = .012) and decreased as level of education increased (primary vs. no education OR = 0.866, p = .001; secondary vs. no education OR = 0.622, p = .003; higher vs. no education OR = 0.323, p< .001).ConclusionsBeing a woman and having a low level of education is associated with an increased risk of violence in older adults. Reducing gender gap and improving access to education for older adults could reduce their risk of violence.  相似文献   
79.
Dietary methionine restriction and supplementation in mammals have beneficial (antiaging) and detrimental effects respectively, which have been related to chronic modifications in the rate of mitochondrial ROS generation. However it is not known if methionine or its metabolites can have, in addition, direct effects on the rate of mitochondrial ROS production. This is studied here for the methionine cycle metabolites S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), homocysteine and methionine itself in isolated rat liver, kidney, heart, and brain mitochondria. The results show that methionine increases ROS production in liver and kidney mitochondria, homocysteine increases it in kidney and decreases it in the other three organs, and SAM and SAH have no effects. The variations in ROS production are localized at complexes I or III. These changes add to previously described chronic effects of methionine restriction and supplementation in vivo.  相似文献   
80.
In biotechnology, endotoxin (LPS) removal from recombinant proteins is a critical and challenging step in the preparation of injectable therapeutics, as endotoxin is a natural component of bacterial expression systems widely used to manufacture therapeutic proteins. The viability of large‐scale industrial production of recombinant biomolecules of pharmaceutical interest significantly depends on the separation and purification techniques used. The aim of this work was to evaluate the use of aqueous two‐phase micellar system (ATPMS) for endotoxin removal from preparations containing recombinant proteins of pharmaceutical interest, such as green fluorescent protein (GFPuv). Partition assays were carried out initially using pure LPS, and afterwards in the presence of E. coli cell lysate. The ATPMS technology proved to be effective in GFPuv recovery, preferentially into the micelle‐poor phase (KGFPuv < 1.00), and LPS removal into the micelle‐rich phase (%REMLPS > 98.00%). Therefore, this system can be exploited as the first step for purification in biotechnology processes for removal of higher LPS concentrations. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
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