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91.
Marcelo Moura Linhares Renato José Affonso Jr Luciano de Souza Viana Sandra Regina Morini Silva Marcos Vinicius Araujo Denadai Silvia Regina Caminada de Toledo Delcio Matos 《PloS one》2015,10(12)
Objective
To evaluate the relationship between the expression profiles of 84 extracellular matrix (ECM) genes and the prognosis of patients with colorectal cancer (CRC).Methods
This retrospective study included 114 patients with stage I–IV CRC who underwent primary tumour resection. Quantitative real-time PCR and immunohistochemistry assays were conducted using primary tumour samples. Kaplan-Meier survival curves were also generated to identify differences in global survival (GS) and disease-free survival (DFS) for the hypo- or hyperexpression status of each marker. The log-rank test was used to verify whether the differences were significant. Stepwise Cox regression models were also used to identify the risk factors associated with GS and DFS in a multivariate mode, and then were used to score the risk of death associated with each marker, either independently or in association.Results
In the univariate analyses, significant differences in GS in relation to the expression profiles of ITGAV (p = 0.001), ITGA3 (p = 0.002), ITGA6 (p = 0.001), SPARC (p = 0.036), MMP9 (p = 0.034), and MMP16 (p = 0.038) were observed. For DFS, significant differences were observed in associated with ITGAV (p = 0.004) and ITGA3 (p = 0.001). However, only the ITGAV and ITGA6 gene markers for GS (hazard ratio (HR) = 3.209, 95% confidence interval (CI) = 1.412–7.293, p = 0.005 and HR = 3.105, 95% CI = 1.367–7.055, p = 0.007, respectively), and ITGA3 for DFS (HR = 3.806, 95% CI = 1.573–9.209, p = 0.003), remained in the final Cox regression models. A scoring system was developed to evaluate the risk of patient death based on the number of markers for the components of the final GS model. Scores of 0, 1, or 2 were associated with the following mean survival rates [CI]: 47.162 [44.613–49.711], 39.717 [35.471–43.964], 30.197 [24.030–36.327], respectively.Conclusions
Multivariate mathematical models demonstrated an association between hyperexpression of the ITGAV and ITGA6 integrins and GS, and also between the ITGA3 integrin and DFS, in patients with colorectal tumours. A risk scoring system based on detected hyperexpression of 0, 1, or 2 markers (e.g., ITGAV and/or ITGA6) was also found to accurately correlate with the GS curves generated for the present cohort. 相似文献92.
A novel endo‐β‐N‐acetylglucosaminidase releases specific N‐glycans depending on different reaction conditions
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Juliana Maria Leite Nobrega De Moura Bell Steven A. Frese Yan Liu David A. Mills David E. Block Daniela Barile 《Biotechnology progress》2015,31(5):1323-1330
Milk glycoproteins are involved in different functions and contribute to different cellular processes, including adhesion and signaling, and shape the development of the infant microbiome. Methods have been developed to study the complexities of milk protein glycosylation and understand the role of N‐glycans in protein functionality. Endo‐β‐N‐acetylglucosaminidase (EndoBI‐1) isolated from Bifidobacterium longum subsp. infantis ATCC 15697 is a recently isolated heat‐stable enzyme that cleaves the N‐N′‐diacetyl chitobiose moiety found in the N‐glycan core. The effects of different processing conditions (pH, temperature, reaction time, and enzyme/protein ratio) were evaluated for their ability to change EndoBI‐1 activity on bovine colostrum whey glycoproteins using advanced mass spectrometry. This study shows that EndoBI‐1 is able to cleave a high diversity of N‐glycan structures. Nano‐LC‐Chip–Q‐TOF MS data also revealed that different reaction conditions resulted in different N‐glycan compositions released, thus modifying the relative abundance of N‐glycan types. In general, more sialylated N‐glycans were released at lower temperatures and pH values. These results demonstrated that EndoBI‐1 is able to release a wide variety of N‐glycans, whose compositions can be selectively manipulated using different processing conditions. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1323–1330, 2015 相似文献
93.
Pengfei Ge Caixia Dong Xiaolan Ren Elisabete Weiderpass Chouji Zhang Haoqiang Fan Jing Zhang Yongrui Zhang Jinen Xi 《PloS one》2015,10(12)
Background
Dyslipidemia is a major health problem in China and an important modifiable cardiovascular disease (CVD) risk factor. This study aimed to describe the prevalence of dyslipidemia and low high density lipoprotein cholesterol (HDL-cholesterol) and associated risk factors among adults in rural northwest China.Methods
In a cross-sectional analyses involving 2,980 adults aged >18 years, information on the demographics, cigarette smoking, alcohol consumption, education, and medical history was collected via face-to-face interviews. Blood samples were collected to determine total cholesterol (TC), low-density lipoprotein cholesterol (LDL-cholesterol), and HDL-cholesterol, and triglycerides (TG) levels.Results
The prevalence of high TC, high LDL-cholesterol, low HDL-cholesterol, and high TG were 1.0%, 0.6%, 60.9%, and 13.7%, respectively. TC, LDL-cholesterol, and TG increased with age in females. Elevated TC was more common in females than in males. The prevalence of low HDL-cholesterol was 67.6% in males and 55.4% in females. Current smokers, those with less education, those who were overweight or obese, and those with large waist circumference were more likely to have low HDL-cholesterol (p<0.05). Multivariable regression showed that male gender showed an association with low HDL-cholesterol (OR 2.10, 95%CI 1.68–2.61), age ≥60 years (OR 0.80, 95% CI 0.64–0.99), BMI (BMI = 24–27.9, OR 1.27, 95%CI 1.04–1.54, p = 0.02 and BMI≥28, OR 1.56, 95%CI 1.10–2.20, p = 0.01) and enlarged waist circumference (OR 2.10, 95%CI 1.51–2.92). Non-alcohol drinker was associated with low HDL-cholesterol levels (OR 0.72, 95%CI 0.53–0.99, p = 0.04).Conclusions
This study found that the prevalence of low HDL-cholesterol was 67.6% and 55.4% for males and females. Male gender, non-alcohol drinker, BMI and central obesity were important risk factors for low HDL-cholesterol in Chinese adults. 相似文献94.
Pedro M. Meirelles Gilberto M. Amado-Filho Guilherme H. Pereira-Filho Hudson T. Pinheiro Rodrigo L. de Moura Jean-Christophe Joyeux Eric F. Mazzei Alex C. Bastos Robert A. Edwards Elizabeth Dinsdale Rodolfo Paranhos Eidy O. Santos Tetsuya Iida Kazuyoshi Gotoh Shota Nakamura Tomoo Sawabe Carlos E. Rezende Luiz M. R. Gadelha Jr Ronaldo B. Francini-Filho Cristiane Thompson Fabiano L. Thompson 《PloS one》2015,10(6)
Seamounts are considered important sources of biodiversity and minerals. However, their biodiversity and health status are not well understood; therefore, potential conservation problems are unknown. The mesophotic reefs of the Vitória-Trindade Seamount Chain (VTC) were investigated via benthic community and fish surveys, metagenomic and water chemistry analyses, and water microbial abundance estimations. The VTC is a mosaic of reef systems and includes fleshy algae dominated rhodolith beds, crustose coralline algae (CCA) reefs, and turf algae dominated rocky reefs of varying health levels. Macro-carnivores and larger fish presented higher biomass at the CCA reefs (4.4 kg per frame) than in the rhodolith beds and rocky reefs (0.0 to 0.1 kg per frame). A larger number of metagenomic sequences identified as primary producers (e.g., Chlorophyta and Streptophyta) were found at the CCA reefs. However, the rocky reefs contained more diseased corals (>90%) than the CCA reefs (~40%) and rhodolith beds (~10%). Metagenomic analyses indicated a heterotrophic and fast-growing microbiome in rocky reef corals that may possibly lead to unhealthy conditions possibly enhanced by environmental features (e.g. light stress and high loads of labile dissolved organic carbon). VTC mounts represent important hotspots of biodiversity that deserve further conservation actions. 相似文献
95.
96.
Brian J. Goodfellow Iven C. N. Duarte Anjos L. Macedo Brian F. Volkman Sofia G. Nunes I. Moura John L. Markley José J. G. Moura 《Journal of biological inorganic chemistry》2010,15(3):409-420
The Ni(II) and Zn(II) derivatives of Desulfovibrio vulgaris rubredoxin (DvRd) have been studied by NMR spectroscopy to probe the structure at the metal centre. The βCH2 proton pairs from the cysteines that bind the Ni(II) atom have been identified using 1D nuclear Overhauser enhancement (NOE)
difference spectra and sequence specifically assigned via NOE correlations to neighbouring protons and by comparison with
the published X-ray crystal structure of a Ni(II) derivative of Clostridium pasteurianum rubredoxin. The solution structures of DvRd(Zn) and DvRd(Ni) have been determined and the paramagnetic form refined using
pseudocontact shifts. The determination of the magnetic susceptibility anisotropy tensor allowed the contact and pseudocontact
contributions to the observed chemical shifts to be obtained. Analysis of the pseudocontact and contact chemical shifts of
the cysteine Hβ protons and backbone protons close to the metal centre allowed conclusions to be drawn as to the geometry
and hydrogen-bonding pattern at the metal binding site. The importance of NH–S hydrogen bonds at the metal centre for the
delocalization of electron spin density is confirmed for rubredoxins and can be extrapolated to metal centres in Cu proteins:
amicyanin, plastocyanin, stellacyanin, azurin and pseudoazurin. 相似文献
97.
Antonio Christian de A. Moura Hermano G. Nunes Alfredo Langguth 《International journal of primatology》2010,31(5):848-862
Food sharing with immatures is an important and relatively well studied aspect of infant care in many cooperative species.
A key point that has not yet been fully addressed, however, is how increasing the difficulty of obtaining food influences
the willingness of breeders and helpers to provision immature offspring. We used captive golden headed lion tamarins (Leontopithecus chrysomelas) to examine how breeders and helpers differ in provisioning juvenile individuals according to the level of difficulty of
obtaining food. The level of difficulty in obtaining food was varied by placing the food inside tubes that allowed access
only by adults. When food acquisition became more difficult, food sharing with juveniles and breeding females increased significantly.
Begging calls by breeding females and juveniles increased during the experimental condition, which probably led to increases
in food sharing. Breeders and helpers did not differ in their contribution to provisioning when food was easily available,
nor did they differ in their contribution when food was difficult to obtain. Breeding males in callitrichids have a prominent
role in transferring food to offspring, but contrary to our expectations, they did not increase food transfer in the experimental
condition. An unexpected result was the increased investment of the breeding female into her current offspring when the level
of difficulty of obtaining food was higher. We suggest that breeding lion tamarin females are not as constrained by reproductive
costs as breeding females of other callitrichids. Degree of reproductive skew is hypothesized as a factor affecting the contribution
of breeders and helpers to offspring care in cooperative breeding mammals, though we suggest that more studies are needed
to validate such a generalization. 相似文献
98.
Carmen Silvia Martimbianco de Figueiredo Durval Batista Palhares Petr Melnikov Aby Jaine da Cruz Montes Moura Sandra Christo dos Santos 《Biological trace element research》2010,136(1):1-7
Zinc and copper are important trace elements in the nutrition of preterm infants. This study determined and compared the concentrations
of zinc and copper in preterm milk of mothers receiving and not receiving zinc supplementation diets. The effects of maternal
supplementation on the blood levels and anthropometric parameters were evaluated. Thirty-eight mothers and their preterm infants
were enrolled in the study. Eighteen mothers were given a daily supplementation of 50 mg zinc, whereas the other 20 were not.
Zinc and copper levels in milk were determined at 15-day intervals, as were blood zinc levels along with anthropometric parameters.
Zinc and copper contents were determined by atomic absorption spectrophotometry. No significant differences were found between
groups either for zinc values in maternal milk and infant blood or for anthropometric measurements. A pronounced decrease
in copper levels was observed in mothers receiving supplemental zinc. Zinc supplementation given to mothers who were breastfeeding
preterm infants had no significant effect on zinc secretion in milk. 相似文献
99.
Relatively few studies have explored sex differences in the use of foraging tools among primates other than apes. Although
male primates are thought to be more innovative, researchers have reported a female sex bias in the use of feeding tools in
wild chimpanzees. We investigate here the nature and extent of sex differences in foraging tool use over 12 mo in a free-ranging
group of bearded capuchins (2 males, 5 females, and 3 juveniles) living in the dry Caatinga forests of the Serra da Capivara
National Park, Piaui, Brazil. These capuchins used 3 major types of feeding tools: 1) tools for probing; 2) tools for pounding/cracking;
and 3) digging stones to extract tubers or roots. Adult males performed 63% (n = 134) of all events of tool use and used tools significantly more frequently than did females, although male bout lengths
across all tools (57 s ± 7.9 SE) were equivalent to those of adult females (47.3 s ± 12.6 SE). Both sexes used digging and
cracking tools, although at different rates, whereas adult males used sticks to probe for prey and other rewards far more
than females. Differential opportunities to use tools were not apparent: >71% of tool-use events occurred on the ground, and
males and females spent equal time on the ground. We suggest that sex differences in tool use may function as opportunities
for male signaling of investment quality. 相似文献
100.
André Almeida Maria Jo?o Moreira Sónia Soares Maria de Lurdes Delgado Jo?o Figueiredo Elisabete Silva António Castro José Manuel Correida Da Cosa 《The Korean journal of parasitology》2010,48(1):43-48
Cryptosporidium and Giardia are 2 protozoan parasites responsible for waterborne diseases outbreaks worldwide. In order to assess the prevalence of these protozoans in drinking water samples in the northern part of Portugal and the risk of human infection, we have established a long term program aiming at pinpointing the sources of surface water, drinking water, and environmental contamination, working with the water-supply industry. Total 43 sources of drinking water samples were selected, and a total of 167 samples were analyzed using the Method 1623. Sensitivity assays regarding the genetic characterization by PCR and sequencing of the genes, 18S SSU rRNA, for Cryptosporidium spp. and β,-giardin for G. duodenalis were set in the laboratory. According to the defined criteria, molecular analysis was performed over 4 samples. Environmental stages of the protozoa were detected in 25.7% (43 out of 167) of the water samples, 8.4% (14 out of 167) with cysts of Giardia, 10.2% (17 out of 167) with oocysts of Cryptosporidium and 7.2% (12 out of 167) for both species. The mean concentrations were 0.1-12.7 oocysts of Cryptosporidium spp. per 10 L and 0.1-108.3 cysts of Giardia duodenalis per 10 L. Our results suggest that the efficiency in drinking water plants must be ameliorated in their efficiency in reducing the levels of contamination. We suggest the implementation of systematic monitoring programs for both protozoa. To authors'' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in drinking water samples in the northern part of Portugal. 相似文献