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51.
Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献
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M L Dowell O J Lakser W T Gerthoffer J J Fredberg G L Stelmack A J Halayko J Solway R W Mitchell 《Journal of applied physiology》2005,98(2):489-497
We hypothesized that differences in actin filament length could influence force fluctuation-induced relengthening (FFIR) of contracted airway smooth muscle and tested this hypothesis as follows. One-hundred micromolar ACh-stimulated canine tracheal smooth muscle (TSM) strips set at optimal reference length (Lref) were allowed to shorten against 32% maximal isometric force (Fmax) steady preload, after which force oscillations of +/-16% Fmax were superimposed. Strips relengthened during force oscillations. We measured hysteresivity and calculated FFIR as the difference between muscle length before and after 20-min imposed force oscillations. Strips were relaxed by ACh removal and treated for 1 h with 30 nM latrunculin B (sequesters G-actin and promotes depolymerization) or 500 nM jasplakinolide (stabilizes actin filaments and opposes depolymerization). A second isotonic contraction protocol was then performed; FFIR and hysteresivity were again measured. Latrunculin B increased FFIR by 92.2 +/- 27.6% Lref and hysteresivity by 31.8 +/- 13.5% vs. pretreatment values. In contrast, jasplakinolide had little influence on relengthening by itself; neither FFIR nor hysteresivity was significantly affected. However, when jasplakinolide-treated tissues were then incubated with latrunculin B in the continued presence of jasplakinolide for 1 more h and a third contraction protocol performed, latrunculin B no longer substantially enhanced TSM relengthening. In TSM treated with latrunculin B + jasplakinolide, FFIR increased by only 3.03 +/- 5.2% Lref and hysteresivity by 4.14 +/- 4.9% compared with its first (pre-jasplakinolide or latrunculin B) value. These results suggest that actin filament length, in part, determines the relengthening of contracted airway smooth muscle. 相似文献
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Rupert CM Jones Maria Dickson-Spillmann Martin JC Mather Dawn Marks Bryanie S Shackell 《Respiratory research》2008,9(1):62
Background
Guidelines on COPD diagnosis and management encourage primary care physicians to detect the disease at an early stage and to treat patients according to their condition and needs. Problems in guideline implementation include difficulties in diagnosis, using spirometry and the disputed role of reversibility testing. These lead to inaccurate diagnostic registers and inadequacy of administered treatments. This study represents an audit of COPD diagnosis and management in primary care practices in Devon.Methods
Six hundred and thirty two patients on COPD registers in primary care practices were seen by a visiting Respiratory Specialist Nurse. Diagnoses were made according to the NICE guidelines. Reversibility testing was carried out either routinely or based on clinical indication in two sub-samples. Dyspnoea was assessed. Data were entered into a novel IT-based software which computed guideline-based treatment recommendations. Current and recommended treatments were compared.Results
Five hundred and eighty patients had spirometry. Diagnoses of COPD were confirmed in 422 patients (73%). Thirty nine patients were identified as asthma only, 94 had normal spirometry, 23 were restrictive and 2 had a cardiac disorder. Reversibility testing changed diagnosis of 11% of patients with airflow obstruction, and severity grading in 18%. Three quarters of patients with COPD had been offered practical help with smoking cessation. Short and long-acting anticholinergics and long acting beta-2 agonists had been under-prescribed; in 15–18% of patients they were indicated but not received. Inhaled steroids had been over-prescribed (recommended in 17%; taken by 60%), whereas only 4% of patients with a chronic productive cough were receiving mucolytics. Pulmonary rehabilitation was not available in some areas and was under-used in other areas.Conclusion
Diagnostic registers of COPD in primary care contain mistakes leading to inaccurate prevalence estimates and inappropriate treatment decisions. Use of pre-bronchodilator readings for diagnosis overestimates the prevalence and severity in a significant minority, thus post bronchodilator readings should be used. Management of stable COPD does often not correspond to guidelines. The IT system used in this study has the potential to improve diagnosis and management of COPD in primary care. 相似文献56.
PJS Amaral LFM Finotelo EHC De Oliveira A Pissinatti CY Nagamachi JC Pieczarka 《BMC evolutionary biology》2008,8(1):169
Background
Chromosomal painting, using whole chromosome probes from humans and Saguinus oedipus, was used to establish karyotypic divergence among species of the genus Cebus, including C. olivaceus, C. albifrons, C. apella robustus and C. apella paraguayanus. Cytogenetic studies suggested that the species of this genus have conservative karyotypes, with diploid numbers ranging from 2n = 52 to 2n = 54. 相似文献57.
Frederiksen CB Lomholt AF Lottenburger T Davis GJ Dowell BL Blankenstein MA Christensen IJ Brunner N Nielsen HJ 《The International journal of biological markers》2008,23(1):42-47
BACKGROUND: Tissue inhibitor of metalloproteinases-1 (TIMP-1) measurements in plasma may be useful for the early detection and prognosis of colorectal cancer (CRC). Data on analytical performance and normal intra- and interindividual biological variation are required in order to interpret the utility of TIMP-1 in CRC. The aim of this study was to establish the biological and analytical variation of plasma TIMP-1 in volunteers. MATERIAL AND METHODS: Three separate studies were undertaken. 1: Plasma was collected from 23 volunteers 6 times within a 3-week period, first in September 2004 (round [R] 1), then repeated in May 2005 (R2) and May 2006 (R3) in the same group of individuals. TIMP-1 levels were determined by the MAC15 ELISA assay and with the Abbott ARCHITECT i2000 Immunoanalyzer. 2: Circadian variation was evaluated in plasma collected 7 times within a 24-hour period (n=16). 3: Effects of physical exercise were evaluated in plasma collected before and after bicycling (n=14). In studies 2 and 3 TIMP-1 levels were determined with the MAC15 ELISA assay only. RESULTS: A significant correlation between TIMP-1 MAC15 and ARCHITECT i2000 was shown (rs=0.78, p<0.002), with consistently higher levels being detected by the ARCHITECT i2000. Median levels of TIMP-1 (ARCHITECT) at 8 a.m. in each round were 74.9 ng/mL (range 65.7-89.9) (R1), 87.3 ng/mL (range 72.7-127.9) (R2), and 81.9 ng/mL (range 66.8-113.6) (R3). The within-subject variation was 10.7%, the variation between rounds was 7.4%, and the intraclass correlation was 46.2%. Comparison between the 3 rounds and time of collection showed that TIMP-1 values decreased by 11% after storage for more than 16 months (p=0.0002). A systematic circadian variation in plasma TIMP-1 levels was not observed (p=0.17). No significant variation of plasma TIMP-1 was found in relation to physical exercise (p=0.92 [global test]). CONCLUSION: Levels of plasma TIMP-1 in volunteers show limited circadian, day-to-day, week-to-week and season-to-season variation. In addition, physical exercise has no impact on plasma TIMP-1 levels. Possible storage-dependent decreases in plasma TIMP-1 levels warrant further investigation. 相似文献
58.
Brockerhoff EG Suckling DM Ecroyd CE Wagstaff SJ Raabe MC Dowell RV Wearings CH 《Journal of economic entomology》2011,104(5):1514-1524
The light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), is a highly successful biological invader. It was accidentally introduced to several countries including New Zealand, Hawaii, England, and California. Light brown apple moth attacks a wide range of crop plants and other woody and herbaceous plants, but a more comprehensive analysis of its host range is needed for risk assessments, to evaluate the likely economic and environmental impacts, and to enable targeting of particular plant species for detection surveys and treatments. We reviewed and synthesized the host range and host selection behavior of light brown apple moth by using information from Australia and invaded countries. The host range of light brown apple moth is determined by the behavior of both adult females and larvae. Females use visual, chemical and physical cues to choose host plants. Larvae are capable of limited active dispersal by walking and longer range dispersal by ballooning on silken strands; therefore, larvae also may need to select host plants. We review larval performance indicators across a range of plants. Based on our review, there are at least 545 plant species in 363 genera from 121 families that have been reported as hosts of light brown apple moth. Some plants were reported only once and need verification. Nevertheless, many host plant species and their wide phylogenetic range (from ferns to higher dicotyledons) indicates that light brown apple moth is one of the most polyphagous insects known. This information and our categorization of frequency of host use are valuable for incursion response and pest management activities. 相似文献
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