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531.
532.
Graphene quantum dots (GQDs), the latest member of the graphene family, have attracted enormous interest in the last few years, due to their exceptional physical, chemical, electrical, optical, and biological properties. Their strong size-dependent photoluminescence and the presence of many reactive groups on the graphene surface allow their multimodal conjugation with therapeutic agents, targeting ligands, polymers, light responsive agents, fluorescent dyes, and functional nanoparticles, making them valuable agents for cancer diagnosis and treatment. In this review, the very recent advances covering the last 3 years on the applications of GQDs as drug delivery systems and theranostic tools for anticancer therapy are discussed, highlighting the relevant factors which regulate their biocompatibility. Among these factors, the size, kind, and degree of surface functionalization have shown to greatly affect their use in biological systems. Toxicity issues, which still represent an open challenge for the clinical development of GQDs based therapeutic agents, are also discussed at cellular and animal levels.  相似文献   
533.
BackgroundCritically ill patients with invasive candidiasis (IC) often suffer renal failure, which sometimes requires continuous renal replacement techniques (CRRT). Echinocandins are the first line treatment for IC in critically ill patients with mild or severe illness. Their elimination during CRRT should be negligible due to their pharmacokinetic and pharmacodynamic (PK/PD) profile, and dose adjustment are not needed, as suggested by the few reported clinical studies.Clinical caseThis is the case of a 66 year old male who underwent surgery due to peritonitis secondary to intestinal suture dehiscence. The patient was admitted to ICU with septic shock symptoms and multiple organ dysfunction syndrome (MODS), and CRRT was started. Anidulafungin was prescribed at the usual dosage due to the IC risk factors present, and the observation of yeasts in the peritoneal fluid. Anidulafungin was selected due to the hepatic failure suffered by the patient. An isolate of Candida albicans susceptible to fluconazole was cultured from peritoneal fluid and rectal exudates. However, anidulafungin was maintained due to the MODS and observing the clearance of fluconazole during CRRT. The patient's condition improved favourably, being moved to the surgical ward 20 days after the surgery.ConclusionsEchinocandins, due to their PK/PD profile, could be safely given at usual doses to critically ill patients undergoing CRRT. However, new studies are required to strengthen this recommendation. Its extrahepatic metabolism makes anidulafungin a more attractive option among echinocandins and other antifungals when used in patients with different degrees of hepatic failure  相似文献   
534.
Emetics can be used to obtain food samples from birds, but they can harm birds during or after treatment. Studies to date suggest that apomorphine is a safe emetic for songbirds, but information is needed about possible post‐release deleterious effects. From March to July 2012, we collected food samples from insectivorous songbirds using apomorphine. We treated 67 Moustached Warblers (Acrocephalus melanopogon), 56 Reed Warblers (Acrocephalus scirpaceus), 15 Great Reed Warblers (Acrocephalus arundinaceus), and 12 Savi's Warblers (Locustella luscinoides). Effectiveness in inducing regurgitation was high (76.7%) and varied among species, being significantly more effective with Reed Warblers (91.1%). No birds died during treatment. To check for possible post‐release negative effects, we considered 53 treated Moustached Warblers and 37 treated Reed Warblers and selected an equal number of untreated individuals (simply captured, banded, and measured). We found no support for differences in survival or recapture probabilities between treated and untreated birds of either species within 21 d after administering apomorphine. We calculated body mass changes of all Moustached Warblers subsequently recaptured (within 21 d) and found no difference between treated (N = 8) and untreated (N = 22) birds, suggesting normal foraging activity after release. Our results suggest that apomorphine is a safe emetic, with no negative effect on survival at least in the short term. The effectiveness of apomorphine with insectivorous songbirds in our study contrasts with the results of some previous studies and confirms the differences in effectiveness among different taxa of songbirds. As with differences in effectiveness among species in our study, this variability in sensitivity to the emetic could be caused by morphological and physiological differences among different taxa.  相似文献   
535.
This paper reports the glutenin diversity of a collection of 23 wild populations of the grass Brachypodium distachyon collected in the Mediterranean and southern areas of the Iberian Peninsula. The plant material studied included the three different cytotypes of this species: 2n?=?10, 2n?=?20 and 2n?=?30. A specific method of extraction was used to isolate the glutenin subunits from the caryopsis. Separation by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed them to correspond to wheat low-molecular-weight glutenin subunits (LMW-GS). Twenty-two LMW-GS?Clike were identified that showed great diversity within and between populations. All the populations investigated were polymorphic for the endosperm proteins studied. The 2n?=?30 forms had the largest number of subunits; these were also more diverse than those of the 2n?=?10 or 2n?=?20 forms. The 2n?=?10 forms, the most common in the higher, interior areas of the Iberian Peninsula, showed the smallest subunit variation. In fact, negative correlations were found between subunit diversity and altitude and longitude. In contrast, a positive correlation was detected with the annual average temperature and the indices of thermicity and Mediterraneity. The similarity between the populations was estimated using the Sorensen?CDice coefficient, calculated on the basis of the presence/absence of the 22 LMW-GS proteins. The similarity indices were used to produce a dendrogram using the unweighted pair-group method with arithmetic means (UPGMA). This method produced three main groups corresponding to the three cytotypes. An analysis was made of the possible correlation between eco-geographic and climatic factors and the gene diversity and polymorphism shown in the populations. The diversity correlated positively with the number of chromosomes (2n), annual mean temperature, index of thermicity and index of Mediterraneity. In contrast, diversity correlated negatively with altitude, longitude and index of precipitation during the summer. The number of chromosomes correlated negatively with altitude, longitude and precipitation during summer and positively with all the other climatic indices. These results are coherent with the fact that diploid forms were more common in areas of the interior and at higher altitude, where the climate is more extreme.  相似文献   
536.
537.
The adaptation to the different biotic and abiotic factors of wine fermentation has led to the accumulation of numerous genomic hallmarks in Saccharomyces cerevisiae wine strains. IRC7, a gene encoding a cysteine-S-β-lyase enzyme related volatile thiols production in wines, has two alleles: a full-length allele (IRC7F) and a mutated one (IRC7S), harbouring a 38 bp-deletion. Interestingly, IRC7S-encoding a less active enzyme – appears widespread amongst wine populations. Studying the global distribution of the IRC7S allele in different yeast lineages, we confirmed its high prevalence in the Wine clade and demonstrated a minority presence in other domesticated clades (Wine-PDM, Beer and Bread) while it is completely missing in wild clades. Here, we show that IRC7S-homozygous (HS) strains exhibited both fitness and competitive advantages compared with IRC7F-homozygous (HF) strains. There are some pieces of evidence of the direct contribution of the IRC7S allele to the outstanding behaviour of HS strains (i.e., improved response to oxidative stress conditions and higher tolerance to high copper levels); however, we also identified a set of sequence variants with significant co-occurrence patterns with the IRC7S allele, which can be co-contributing to the fitness and competitive advantages of HS strains in wine fermentations.  相似文献   
538.
A total of 25 patients who underwent bilateral breast reduction were included in this study. Each patient's age, weight, height, and amount of breast tissue removed from each breast were recorded. The body mass index was calculated for each patient. On the day of the operation, tissue samples (two each) were taken from the central, lateral, and preaxillary areas of the breast. One of the samples was weighed, placed in a closed glass container, and heated for 10 minutes in a microwave oven at full power. The liquid fat was separated from the solid residue, and the percentage of fat was calculated. The other sample from each area was examined grossly, and representative sections, corresponding to the distribution of fat and connective tissue, were submitted for evaluation. In these samples, the percentage of fat, gland, and connective tissue was estimated using low-magnification light microscopy. In this group of patients (who had an average age of 34 years and who were significantly overweight as determined by a mean body mass index of 28), it was found (using the microwave method) that there was a mean fat percentage of 61 percent in the central breast area, 74 percent in the lateral breast area, and 73 percent in the preaxillary area. Upon microscopic examination, the pathologist reported that fat accounted for 64 percent of the central breast area, 92 percent of the lateral breast area, and 94 percent of the preaxillary area. On average, the central breast area in macromastia patients had only seven percent gland and 29 percent connective tissue. The lateral and preaxillary areas of the breast had one to three percent gland and five percent connective tissue. The two methods had a significant (p < 0.05) positive correlation in the central breast area, but in the lateral and preaxillary regions, the correlation was poor. In the microscopic examination, there was a tendency to overestimate the amount of fat. Both methods of evaluation used in the study concur that the enlarged breast of macromastia consists primarily of fat and that the glandular element is rather small.  相似文献   
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