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101.

Introduction

Pneumonia is the most frequent type of infection in cancer patients and a frequent cause of ICU admission. The primary aims of this study were to describe the clinical and microbiological characteristics and outcomes in critically ill cancer patients with severe pneumonia.

Methods

Prospective cohort study in 325 adult cancer patients admitted to three ICUs with severe pneumonia not acquired in the hospital setting. Demographic, clinical and microbiological data were collected.

Results

There were 229 (71%) patients with solid tumors and 96 (29%) patients with hematological malignancies. 75% of all patients were in septic shock and 81% needed invasive mechanical ventilation. ICU and hospital mortality rates were 45.8% and 64.9%. Microbiological confirmation was present in 169 (52%) with a predominance of Gram negative bacteria [99 (58.6%)]. The most frequent pathogens were methicillin-sensitive S. aureus [42 (24.9%)], P. aeruginosa [41(24.3%)] and S. pneumonia [21 (12.4%)]. A relatively low incidence of MR [23 (13.6%)] was observed. Adequate antibiotics were prescribed for most patients [136 (80.5%)]. In multivariate analysis, septic shock at ICU admission [OR 5.52 (1.92–15.84)], the use of invasive MV [OR 12.74 (3.60–45.07)] and poor Performance Status [OR 3.00 (1.07–8.42)] were associated with increased hospital mortality.

Conclusions

Severe pneumonia is associated with high mortality rates in cancer patients. A relatively low rate of MR pathogens is observed and severity of illness and organ dysfunction seems to be the best predictors of outcome in this population.  相似文献   
102.

Background

Leishmania is transmitted by Phlebotominae insects that maintain the enzootic cycle by circulating between sylvatic and domestic mammals; humans enter the cycles as accidental hosts due to the vector’s search for blood source. In Colombia, leishmaniasis is an endemic disease and 95% of all cases are cutaneous (CL), these cases have been reported in several regions of the country where the intervention of sylvatic areas by the introduction of agriculture seem to have an impact on the rearrangement of new transmission cycles. Our study aimed to update vector species distribution in the country and to analyze the relationship between vectors’ distribution, climate, land use and CL prevalence.

Methods

A database with geographic information was assembled, and ecological niche modeling was performed to explore the potential distribution of each of the 21 species of medical importance in Colombia, using thirteen bioclimatic variables, three topographic and three principal components derived from NDVI. Binary models for each species were obtained and related to both land use coverage, and a CL prevalence map with available epidemiological data. Finally, maps of species potential distribution were summed to define potential species richness in the country.

Results

In total, 673 single records were obtained with Lutzomyia gomezi, Lutzomyia longipalpis, Psychodopygus panamensis, Psathyromyia shannoni and Pintomyia evansi the species with the highest number of records. Eighteen species had significant models, considering the area under the curve and the jackknife results: L. gomezi and P. panamensis had the widest potential distribution. All sand fly species except for Nyssomyia antunesi are mainly distributed in regions with rates of prevalence between 0.33 to 101.35 cases per 100,000 inhabitants and 76% of collection data points fall into transformed ecosystems.

Discussion

Distribution ranges of sand flies with medical importance in Colombia correspond predominantly to disturbed areas, where the original land coverage is missing therefore increasing the domiciliation potential. We highlight the importance of the use of distribution maps as a tool for the development of strategies for prevention and control of diseases.  相似文献   
103.
Nuclear insertions of mitochondrial origin (NUMTs) can be useful tools in evolution and population studies. However, due to their similarity to mitochondrial DNA (mtDNA), NUMTs may also be a source of contamination in mtDNA studies. The main goal of this work is to present a database of NUMTs, based on the latest version of the human genome—GRCh37 draft. A total of 755 insertions were identified. There are 33 paralogous sequences with over 80% sequence similarity and of a greater length than 500 bp. The non-identical positions between paralogous sequences are listed for the first time. As an application example, the described database is used to evaluate the impact of NUMT contamination in cancer studies. The evaluation reveals that 220 positions from 256 with zero hits in the current mtDNA phylogeny could in fact be traced to one or more nuclear insertions of mtDNA. This is due to they are located in non-identical positions between mtDNA and nuclear DNA (nDNA). After in silico primer validation of each revised cancer study, risk of co-amplification between mtDNA and nDNA was detected in some cases, whereas in others no risk of amplification was identified. This approach to cancer studies clearly proves the potential of our NUMT database as a valuable new tool to validate mtDNA mutations described in different contexts. Moreover, due to the amount of information provided for each nuclear insertion, this database should play an important role in designing evolutionary, phylogenetic and epidemiological studies.  相似文献   
104.
Enabled/Vasodilator-stimulated phosphoprotein (Ena/VASP) protein family members link actin dynamics and cellular signaling pathways. VASP localizes to regions of dynamic actin reorganization such as the focal adhesion contacts, the leading edge or filopodia, where it contributes to F-actin filament elongation. Here we identify VASP as a novel substrate for protein kinase D1 (PKD1). We show that PKD1 directly phosphorylates VASP at two serine residues, Ser-157 and Ser-322. These phosphorylations occur in response to RhoA activation and mediate VASP re-localization from focal contacts to the leading edge region. The net result of this PKD1-mediated phosphorylation switch in VASP is increased filopodia formation and length at the leading edge. However, such signaling when persistent induced membrane ruffling and decreased cell motility.  相似文献   
105.
Heteroxenic and monoxenic trypanosomatids were screened for the presence of actin using a mouse polyclonal antibody produced against the entire sequence of the Trypanosoma cruzi actin gene, encoding a 41.9 kDa protein. Western blot analysis showed that this antibody reacted with a polypeptide of approximately 42 kDa in the whole-cell lysates of parasites targeting mammals (T. cruzi, Trypanosoma brucei and Leishmania major), insects (Angomonas deanei, Crithidia fasciculata, Herpetomonas samuelpessoai and Strigomonas culicis) and plants (Phytomonas serpens). A single polypeptide of approximately 42 kDa was detected in the whole-cell lysates of T. cruzi cultured epimastigotes, metacyclic trypomastigotes and amastigotes at similar protein expression levels. Confocal microscopy showed that actin was expressed throughout the cytoplasm of all the tested trypanosomatids. These data demonstrate that actin expression is widespread in trypanosomatids.  相似文献   
106.
Marine protected areas (MPAs) are promoted as an effective strategy to balance human use and conservation of marine resources, yet case studies have shown mixed results regarding MPA success. Managing to promote resilience is widely recognized as a priority for MPAs that focus on the conservation of coral reefs and the ecological services they provide. To this end, there is an acute need to develop and implement methods that assimilate monitoring results into comprehensive summaries that can be understood and acted upon by local management to promote resilience. We used the Parque Nacional Arrecife de Puerto Morelos (PNAPM) as a model MPA to evaluate the utility of a resilience index framework proposed by Maynard et al. (Coral Reefs 29:381–391, 2010b) that uses a suite of broad- and local-scale indicators to rank the relative resilience of sites. Based on monitoring data we identify local stressors adversely impacting coral reef resilience that can be influenced by management actions. Improving regulation enforcement, conducting targeted invasive species removals, reallocating and restricting tourist activities, and establishing nutrient level regulations were identified as realistic adaptive management actions to promote resilience within the PNAPM. This first application of the Maynard et al. (Coral Reefs 29:381–391, 2010b) resilience index framework to a Caribbean MPA provides an example for MPA managers of the value of their monitoring data and the utility of a broadly applicable management tool to assist in managerial decisions. Moving beyond simply monitoring sites to management action is essential to promote resilience and maintain the health and existence of coral reef ecosystems.  相似文献   
107.
doi:10.1111/j.1741‐2358.2009.00318.x
Palatal and mandibular tori in a Romanian removable denture‐wearing population Objective: To establish the prevalence of palatal tori (TP) and mandibular tori (TM) in a Romanian denture‐wearing population in order to see how or if tori influenced the denture design or the treatment planning. Background data: There are no available data regarding tori in an elderly Romanian population and its implication for treatment planning. It could be considered a local factor influencing the quality of prosthetic treatment. Material and method: Tori prevalence was investigated in 251 patients, with an average age of 62 years. A statistical analysis was made, using odds ratio (OR) for the distribution related to gender and the Chi‐squared test for the differences in prevalence related to age groups. Treatment planning difficulties because of presence of tori were recorded. Results: Frequency of TP was significantly higher in both genders (OR = 2.0661 and p = 0.0446) and non‐significant frequency for distribution between genders for TM (OR = 0.9421 and p = 0.8273). The differences in age groups showed both tori types have a variable prevalence related to age. The most frequent location for TP was found in the posterior one‐third and two‐thirds of the palate and for TM in the canine and first premolar area presenting with different sizes. Conclusions: Tori prevalence in our study group is high and is significantly related to age (p < 0.05) having a peak at over 60 years. The preferential site of TP in the posterior palatal area and this location has an impact on decision making in treatment planning for the upper denture.  相似文献   
108.
Aluminum (Al3+) has been recognized as a main toxic factor in crop production in acid lands. Phosphatidic acid (PA) is emerging as an important lipid signaling molecule and has been implicated in various stress-signaling pathways in plants. In this paper, we focus on how PA generation is affected by Al3+ using Coffea arabica suspension cells. We pre-labeled cells with [32P]orthophosphate (32Pi) and assayed for 32P-PA formation in response to Al3+. Treating cells for 15 min with either AlCl3 or Al(NO3)3 inhibited the formation of PA. In order to test how Al3+ affected PA signaling, we used the peptide mastoparan-7 (mas-7), which is known as a very potent stimulator of PA formation. The Al3+ inhibited mas-7 induction of PA response, both before and after Al3+ incubation. The PA involved in signaling is generated by two distinct phospholipid signaling pathways, via phospholipase D (PLD; EC: 3.1.4.4) or via Phospholipase C (PLC; EC: 3.1.4.3), and diacylglycerol kinase (DGK; EC 2.7.1.107). By labeling with 32Pi for short periods of time, we found that PA formation was inhibited almost 30% when the cells were incubated with AlCl3 suggesting the involvement of the PLC/DGK pathway. Incubation of cells with PLC inhibitor, U73122, affected PA formation, like AlCl3 did. PLD in vivo activation by mas-7 was reduced by Al3+. These results suggest that PA formation was prevented through the inhibition of the PLC activity, and it provides the first evidence for the role of Al toxicity on PA production.  相似文献   
109.
The crab-eating fox is a medium-sized Neotropical canid with generalist habits and a broad distribution in South America. We have investigated its genetic diversity, population structure and demographic history across most of its geographic range by analysing 512 base pairs (bp) of the mitochondrial DNA (mtDNA) control region, 615 bp of the mtDNA cytochrome b gene and 1573 total nucleotides from three different nuclear fragments. MtDNA data revealed a strong phylogeographic partition between northeastern Brazil and other portions of the species' distribution, with complete separation between southern and northern components of the Atlantic Forest. We estimated that the two groups diverged from each other c. 400,000-600,000 years ago, and have had contrasting population histories. A recent demographic expansion was inferred for the southern group, while northern populations seem to have had a longer history of large population size. Nuclear sequence data did not support this north-south pattern of subdivision, likely due at least in part to secondary male-mediated historical gene flow, inferred from multilocus coalescent-based analyses. We have compared the inferred phylogeographic patterns to those observed for other Neotropical vertebrates, and report evidence for a major north-south demographic discontinuity that seems to have marked the history of the Atlantic Forest biota.  相似文献   
110.
Biodiversity and Conservation - Mediterranean countries are still characterized by a great variety of historical cultural landscapes, as a result of the millenary human presence that has shaped the...  相似文献   
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