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991.
Casas-Vargas A Gómez A Briceño I Díaz-Matallana M Bernal JE Rodríguez JV 《American journal of physical anthropology》2011,146(4):637-649
Ancient DNA was recovered from 17 individuals found in a rock shelter in the district of "La Purnia" (Santander, Colombia). This region is the homeland of pre-Columbian Guane, whom spread over the "Río Suarez" to the "Río de Oro", and were surrounded to the west by the Central Andes, south and east by foothills of Eastern Andes, and north by the "Chicamocha" river canyon. Guanes established in a region that straddles the Andes and the northern Amazon basin, possibly making it an unavoidable conduit for people moving to and from South America. We amplified mtDNA hypervariable region I (HVI) segments from ancient bone remains, and the resulting sequences were compared with both ancient and modern mitochondrial haplogroups from American and non-American populations. Samples showed a distribution of 35% for haplogroup A, 41% for haplogroup B and 24% for haplogroup D. Nine haplotypes were found in 17 samples, indicating an unusually high genetic diversity on a single site ancient population. Among them, three haplotypes have not been previously found in America, two are shared in Asia, and one is a private haplotype. Despite geographical barriers that eventually isolated them, an important influence of gene flow from neighboring pre-Columbian communities, mainly Muiscas, could explain the high genetic polymorphism of this community before the Spanish conquest, and argues against Guanes as being a genetic isolate. 相似文献
992.
Rodrigo Bernal Claudia Torres Néstor García Carolina Isaza Jaime Navarro Martha Isabel Vallejo Gloria Galeano Henrik Balslev 《The Botanical review》2011,77(4):607-646
We reviewed information on management of useful palms in South America. We documented management for 96 species, from incidental
activities intended to increase populations of wild palms to the inclusion of palms in complex agroforestry systems. Two species,
Bactris gasipaes and Parajubaea cocoides, are domesticated. Managed species are remarkably fewer than species used in the region, which suggests that harvesters often
disregard the fate of the species they use. The best way of managing palms is to employ harvest methods that do not decimate
the populations. Although a variety of harvesting techniques have been documented, overharvest is common, and mismanagement
prevails – unnecessary felling of palms in order to harvest leaves or fruits is a widespread practice. Research should focus
on assessing production in response to management practices, but eradicating the habit of destructive harvest is an obvious
priority. Research on palm management must be combined with actions addressed to all stakeholders of the palm/humans system. 相似文献
993.
Common variable immunodeficiency (CVID) is a primary immunodeficiency characterised by hypogammaglobulinaemia and antibody deficiency to T dependent and independent antigens. Patients suffer from recurrent respiratory infections and poor response to vaccination. Although the underlying molecular defect is unknown, most CVID patients show impaired late B cell differentiation. We investigated B cell differentiation and immunoglobulin secretion induced by two different stimuli: TLR9 specific ligand (CpG-ODN) and anti-CD40 combined with IL21. The contribution of BCR signalling (anti-IgM stimulation) was also evaluated. B cells from CVID patients produced low levels of IgG and IgA in response to both kinds of stimuli that was not restored by anti-IgM. Production of IgM was conserved when cells were stimulated with anti-CD40 and IL21. These results point to a wide signalling defect in B lymphocytes from CVID patients that may be related to their hypogammaglobulinaemia and poor response to vaccination. 相似文献
994.
Jaime C. Piñero Steven K. Souder Roger I. Vargas 《Entomologia Experimentalis et Applicata》2020,168(4):339-348
Attraction of tephritid fruit flies to some food sources can be enhanced by the presence of ammonia derivatives, compounds that are perceived as volatile cues for protein-rich food sources. Using a comparative approach, we (1) evaluated the behavioral responses of females of three invasive fruit fly species, Bactrocera (Zeugodacus) cucurbitae (Coquillett), Bactrocera dorsalis (Hendel), and Ceratitis capitata (Wiedemann) (all Diptera: Tephritidae) to trub (a protein-rich waste brewer’s yeast product generated during the production of beer), Concord grape juice (a protein-deficient material), and ammonium acetate, and (2) identified synergistic and additive interactions between low- and high-attractiveness materials and ammonium acetate. We established the attractiveness of fresh trub, grape juice, and ammonium acetate when tested singly to females of all three fly species. Although ammonium acetate did not enhance significantly the response of females of any species to fresh trub, the most attractive material, ammonium acetate, did significantly enhance females’ level of response to aged trub (a comparatively less attractive material) and to grape juice. Our research found a synergistic interaction between diluted grape juice and ammonium acetate for B. cucurbitae, as well as between aged trub and ammonium acetate for B. dorsalis. For C. capitata, additive effects among food attractants and ammonium acetate were identified. Our findings increase our understanding of fruit fly female olfactory-driven behavior in response to food-based materials and the extent to which ammonium acetate modulates female response to protein-rich and protein-deficient materials. 相似文献
995.
Masha T. van der Sande Helge Bruelheide Wayne Dawson Jürgen Dengler Franz Essl Richard Field Sylvia Haider Mark van Kleunen Holger Kreft Joern Pagel Jan Pergl Oliver Purschke Petr Pyek Patrick Weigelt Marten Winter Fabio Attorre Isabelle Aubin Erwin Bergmeier Milan Chytrý Matteo Dainese Michele De Sanctis Jaime Fagundez Valentin Golub Greg R. Guerin Alvaro G. Gutirrez Ute Jandt Florian Jansen Borja Jimnez‐Alfaro Jens Kattge Elizabeth Kearsley Stefan Klotz Koen Kramer Marco Moretti Ülo Niinemets Robert K. Peet Josep Penuelas Petr Petík Peter B. Reich Brody Sandel Marco Schmidt Maria Sibikova Cyrille Violle Timothy J. S. Whitfeld Thomas Wohlgemuth Tiffany M. Knight 《Global Ecology and Biogeography》2020,29(2):281-294
996.
Carole D. Mitnick Molly F. Franke Michael L. Rich Felix A. Alcantara Viru Sasha C. Appleton Sidney S. Atwood Jaime N. Bayona Cesar A. Bonilla Katiuska Chalco Hamish S. F. Fraser Jennifer J. Furin Dalia Guerra Rocio M. Hurtado Keith Joseph Karim Llaro Lorena Mestanza Joia S. Mukherjee Maribel Mu?oz Eda Palacios Epifanio Sanchez Kwonjune J. Seung Sonya S. Shin Alexander Sloutsky Arielle W. Tolman Mercedes C. Becerra 《PloS one》2013,8(3)
Rationale
A better understanding of the composition of optimal treatment regimens for multidrug-resistant tuberculosis (MDR-TB) is essential for expanding universal access to effective treatment and for developing new therapies for MDR-TB. Analysis of observational data may inform the definition of an optimized regimen.Objectives
This study assessed the impact of an aggressive regimen–one containing at least five likely effective drugs, including a fluoroquinolone and injectable–on treatment outcomes in a large MDR-TB patient cohort.Methods
This was a retrospective cohort study of patients treated in a national outpatient program in Peru between 1999 and 2002. We examined the association between receiving an aggressive regimen and the rate of death.Measurements and Main Results
In total, 669 patients were treated with individualized regimens for laboratory-confirmed MDR-TB. Isolates were resistant to a mean of 5.4 (SD 1.7) drugs. Cure or completion was achieved in 66.1% (442) of patients; death occurred in 20.8% (139). Patients who received an aggressive regimen were less likely to die (crude hazard ratio [HR]: 0.62; 95% CI: 0.44,0.89), compared to those who did not receive such a regimen. This association held in analyses adjusted for comorbidities and indicators of severity (adjusted HR: 0.63; 95% CI: 0.43,0.93).Conclusions
The aggressive regimen is a robust predictor of MDR-TB treatment outcome. TB policy makers and program directors should consider this standard as they design and implement regimens for patients with drug-resistant disease. Furthermore, the aggressive regimen should be considered the standard background regimen when designing randomized trials of treatment for drug-resistant TB. 相似文献997.
Huey Fang Teh Bee Keat Neoh May Ping Li Hong Jaime Yoke Sum Low Theresa Lee Mei Ng Nalisha Ithnin Yin Mee Thang Mohaimi Mohamed Fook Tim Chew Hirzun Mohd. Yusof Harikrishna Kulaveerasingam David R. Appleton 《PloS one》2013,8(4)
To better understand lipid biosynthesis in oil palm mesocarp, in particular the differences in gene regulation leading to and including de novo fatty acid biosynthesis, a multi-platform metabolomics technology was used to profile mesocarp metabolites during six critical stages of fruit development in comparatively high- and low-yielding oil palm populations. Significantly higher amino acid levels preceding lipid biosynthesis and nucleosides during lipid biosynthesis were observed in a higher yielding commercial palm population. Levels of metabolites involved in glycolysis revealed interesting divergence of flux towards glycerol-3-phosphate, while carbon utilization differences in the TCA cycle were proven by an increase in malic acid/citric acid ratio. Apart from insights into the regulation of enhanced lipid production in oil palm, these results provide potentially useful metabolite yield markers and genes of interest for use in breeding programmes. 相似文献
998.
Fredy Roberto Salazar Gutierrez Martha Liliana Trujillo Güiza Magally del Carmen Escobar Martínez 《PLoS neglected tropical diseases》2013,7(3)
The purpose of this study was to calculate the seroprevalence of Trypanosoma cruzi infection in a sample of inhabitants from a region considered to be at high risk of natural transmission of Chagas disease in Colombia. A cross-sectional study was conducted in subjects from 5 municipalities, recruited in urban and rural locations, distributed by gender according to the demographic information available. Socio-demographic information, history of potential exposure to insect vectors, blood donating, as well as symptoms suggesting cardiac disease were collected using a questionnaire. After giving written informed consent, blood specimens were obtained from 486 people to determine the serologic evidence of past exposure to T. cruzi. Infection was diagnosed when two different tests (ELISA and IHA) were positive. The seroprevalence of antibodies against T. cruzi was 16.91% considering an estimated population of 44,355 aged between 15 and 89 years (95%IC: 13.72 to 20.01). The factors significantly associated with the infection were: 1- Housing materials like vegetable material, adobe or unfinished brick walls; 2- The fact of having previous tests for Chagas disease (regardless of the result). Of note, the mean ages among infected and not infected participants were significantly different (49.19 vs. 41.66, p≤0.0001). Among the studied municipalities, the one with the highest frequency of T. cruzi infection was Nunchia, with 31.15% of the surveyed subjects. Therefore it may be concluded that T. cruzi infection is highly prevalent in the north region of Casanare, in Colombia. 相似文献
999.
R?nnaug Solberg Javier Escobar Alessandro Arduini Isabel Torres-Cuevas Agustín Lahoz Juan Sastre Ola Didrik Saugstad Máximo Vento Julia Kuligowski Guillermo Quintás 《PloS one》2013,8(6)
The availability of reliable biomarkers of brain injury secondary to birth asphyxia could substantially improve clinical grading, therapeutic intervention strategies, and prognosis. In this study, changes in the metabolome of retinal tissue caused by profound hypoxia in an established neonatal piglet model were investigated using an ultra performance liquid chromatography – quadrupole time of flight mass spectrometry (UPLC-QTOFMS) untargeted metabolomic approach, which included Partial Least Squares – Discriminant Analysis (PLSDA) multivariate data analysis. The initial identification of a set of discriminant metabolites from UPLC-QTOFMS data was confirmed by target UPLC-MS/MS and allowed the selection of endogenous CDP-choline as a promising candidate biomarker for hypoxia-derived brain damage assessing intensity of retinal hypoxia. Results from this study will foster further research on CDP-choline changes occurring during resuscitation. 相似文献
1000.
Yagahira E. Castro-Sesquen Robert H. Gilman Verónica Yauri Jaime Cok Noelia Angulo Hermes Escalante Caryn Bern 《PloS one》2013,8(3)
The diagnosis of Chagas disease in humans is generally limited to the detection of specific antibodies. Detection of T. cruzi antigens in urine has been reported previously, but is not used in the diagnosis. In this study, soluble T. cruzi antigens and DNA were detected in urine samples and were associated with kidney injury and systemic detection of the parasite. We used 72 guinea pigs infected with T. cruzi Y strain and 18 non-infected guinea pigs. Blood, kidney, heart and urine samples were collected during the acute phase and chronic phase. Urine samples were concentrated by ultrafiltration. Antigens were detected by Western Blot using a polyclonal antibody against trypomastigote excretory-secretory antigen (TESA). T. cruzi DNA was detected by PCR using primers 121/122 and TcZ1/TcZ2. Levels of T. cruzi DNA in blood, heart and kidney were determined by quantitative PCR. T. cruzi antigens (75 kDa, 80 kDa, 120 kDa, 150 kDa) were detected in the acute phase (67.5%) and the chronic phase (45%). Parasite DNA in urine was detected only in the acute phase (45%). Kidney injury was characterized by high levels of proteinuria, kidney injury molecule-1 (KIM-1) and urea, and some histopathological changes such as inflammation, necrosis, fibrosis and scarce parasites. The detection of antigens and DNA in urine was associated with the presence of parasite DNA in blood and heart and with high levels of parasite DNA in blood, but not with the presence of parasite in kidney or kidney injury. These results suggest that the detection of T. cruzi in urine could be improved to be a valuable method for the diagnosis of Chagas disease, particularly in congenital Chagas disease and in immunocompromised patients. 相似文献