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101.
Christian Pansch Iris Schaub Jonathan Havenhand Martin Wahl 《Global Change Biology》2014,20(3):765-777
Energy availability and local adaptation are major components in mediating the effects of ocean acidification (OA) on marine species. In a long‐term study, we investigated the effects of food availability and elevated pCO2 (ca. 400, 1000 and 3000 μatm) on growth of newly settled Amphibalanus (Balanus) improvisus to reproduction, and on their offspring. We also compared two different populations, which were presumed to differ in their sensitivity to pCO2 due to differing habitat conditions: Kiel Fjord, Germany (Western Baltic Sea) with naturally strong pCO2 fluctuations, and the Tjärnö Archipelago, Sweden (Skagerrak) with far lower fluctuations. Over 20 weeks, survival, growth, reproduction and shell strength of Kiel barnacles were all unaffected by elevated pCO2, regardless of food availability. Moulting frequency and shell corrosion increased with increasing pCO2 in adults. Larval development and juvenile growth of the F1 generation were tolerant to increased pCO2, irrespective of parental treatment. In contrast, elevated pCO2 had a strong negative impact on survival of Tjärnö barnacles. Specimens from this population were able to withstand moderate levels of elevated pCO2 over 5 weeks when food was plentiful but showed reduced growth under food limitation. Severe levels of elevated pCO2 negatively impacted growth of Tjärnö barnacles in both food treatments. We demonstrate a conspicuously higher tolerance to elevated pCO2 in Kiel barnacles than in Tjärnö barnacles. This tolerance was carried over from adults to their offspring. Our findings indicate that populations from fluctuating pCO2 environments are more tolerant to elevated pCO2 than populations from more stable pCO2 habitats. We furthermore provide evidence that energy availability can mediate the ability of barnacles to withstand moderate CO2 stress. Considering the high tolerance of Kiel specimens and the possibility to adapt over many generations, near future OA alone does not seem to present a major threat for A. improvisus. 相似文献
102.
目的:观察步长稳心颗粒(简称稳心颗粒)治疗功能性早搏的临床疗效及安全性。方法:选择功能性早搏60例病人,随机分为治疗组及对照组,每组各30例。治疗组给予稳心颗粒一包(9克),每日三次,温开水冲服;对照组给予倍他乐克25毫克,每日二次口服,一个月为一疗程。结果:四周后治疗组显效11例,有效16例,总有效率90%。对照组显效8例,有效18例,总有效率86.7%,p〉0.05,两组比较无显著性差异。对血压、心率影响方面稳心颗粒明显优于倍他乐克结论:稳心颗粒治疗功能性早搏疗效显著,且效果稳定,安全无明显不良反应,值得临床推广应用。 相似文献
103.
《Journal of Industrial Ecology》2004,8(1-2):11-21
Land use is an increasingly important component of sustainability evaluations, and numerous performance metrics have evolved to meet this need. The selection of appropriate land-use metrics for decision makers, however, remains an ongoing challenge. Additionally, life-cycle practitioners often struggle to provide meaningful impact assessment because of challenges associated with traditional land-use impact metrics. This article is intended to assist decision makers and life-cycle practitioners who wish to more effectively measure and evaluate one aspect of land use: surface area occupation. Existing performance metrics are discussed, and the specific circumstances under which each is appropriate are identified. Building on leading-edge research and analysis in the field of life-cycle impact assessment, a modified methodology for evaluating surface area occupation is proposed. This approach is demonstrated for a series of mining practices including three individual gold mines, a bauxite mine, and a copper mine. The specific data requirements and resulting equivalency factors for each mine are discussed. Results indicate that equivalency factors for gold (average of 700 acre-yr/ton) are expected to be several orders of magnitude higher than for either bauxite (0.004 acre-yr/ ton) or copper (0.03 acre-yr/ton). These dramatic differences in results demonstrate that equivalency factors are appropriate and necessary for including land-use impact potential as part of a life-cycle assessment that includes several different minerals or material requirements. 相似文献
104.
Gokhan Zengin Ramazan Ceylan Abdurrahman Aktumsek 《Journal of enzyme inhibition and medicinal chemistry》2016,31(5):754-759
Plant-based foods have become attractive for scientists and food producers. Beneficial effects related to their consumption as dietary supplements are due to the presence of natural occurring secondary metabolites. In this context, studies on these products are important for natural and safely food ingredients evaluation. The aim of this study was to evaluate root extract of eight Asphodeline species as antioxidants, enzyme inhibitors and phytochemical content. Spectrophotometric antioxidant and enzyme inhibitory assays were performed. Total phenolic and flavonoids contents as well as the chemical free-anthraquinones profiles were determined using routinely procedure (HPLC-PDA). Data show that Asphodeline roots can be considered as a new source of natural compounds and can be used as a valuable dietary supplement. Some differences related to biological activities can be inferred to other phytochemicals that can be considered in the future for their synergic or competitive activities. 相似文献
105.
Helmut Segner Roland Marthaler Michael Linnenbach 《Environmental Biology of Fishes》1988,21(2):153-159
Synopsis Young (7–10 days after hatching) brown trout (Salmo trutta) exposed for 5 days to pH 5 in high calcium water and at 2 temperatures (12°, 4°C) in the laboratory displayed no alterations
in growth or in mucous cell concentration and volume, compared to the control group kept at pH 7.2. Contamination of acid-stressed
young with 230 μg All-1 resulted in significant growth depression and Al accumulation, but in no changes of mucous cell morphometrics. Field tests
in low calcium water produced high mortality at low pH (5.1), but showed consistent effects on mucous cells as in laboratory
experiments. Three-month-old juveniles of brown trout, subjected to decreased pH values at 12° and in high calcium water for
8 days exhibited mucous cell hyperplasia (without hypertrophy) within 3 h of the acid addition. After 120 h sloughing of the
integument occurred with full recovery not possible within a 4-day-recovery period. Although the results presently apply only
to hard water conditions, the differences between juveniles and recently hatched young in tolerance to pH- and Al-mediated
stress may also be of importance for soft waters affected by acid rain. 相似文献
106.
采用PCR-SSCP方法检测猪胰岛素样生长因子2 (insulin-like growth factor 2,IGF2)基因外显子3多态性,分析其对初生重、断奶重、6月龄重和背膘厚的遗传效应.根据猪IGF2基因的DNA序列(AY044828)设计引物,结果在其扩增片段上检测到多态性,对纯合子进行测序,发现IGF2-ex3-A36T和IGF2-ex3-G109A两个多态性位点,并且这2个多态性位点完全连锁,检测到3种基因型(A36A/G109G,A36T/G109A 和 T36T/A109A).统计结果表明,基因型在各品种中分布不一致,长白猪和大白猪与莱芜猪、大薄莲猪、沂蒙黑猪和里岔黑猪比较基因型分布差异极显著(P<0.01);其它猪种间基因型分布差异均不显著(P>0.05).固定效应模型分析结果表明,初生重和背膘厚基因型间差异显著(P<0.05),而断奶重和6月龄重基因型间差异不显著(P>0.05).最小二乘分析结果表明,A36A/G109G基因型个体同A36T/G109A和 T36T/A109A基因型个体比较初生重和背膘厚的差异显著(P<0.05),3种基因型初生重的大小排列顺序为A36A/G109G < A36T/G109A < T36T/A109A,背膘厚的大小排列顺序为A36A/G109G > A36T/G109A >T36T/A109A.因此,推测IGF2基因对个体的初生重和胴体瘦肉率存在一定的影响,将IGF2基因应用于猪育种过程中的标记辅助选择,将可以改善猪肉品质,加快猪的育种进程. 相似文献
107.
Fiorito F Pagnini U De Martino L Montagnaro S Ciarcia R Florio S Pacilio M Fucito A Rossi A Iovane G Giordano A 《Journal of cellular biochemistry》2008,103(1):221-233
Dioxin-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a common environmental toxin of current interest. In the last years, higher levels of TCDD than those permitted in UE [European Commission. 2002. European Commission Recommendation 2002/201/CE. Official Gazette, L 67/69] were detected in milk samples from cow, water buffalo, goat, and sheep raised on some areas of Campania Region (South Italy). Dioxin often causes immunosuppression and might render the animal liable to viral infections. In addition, viral infections are able to alter the pattern of dioxin distribution in different organs of the exposed animals. Bovine Herpesvirus type-1 (BHV-1) is a widespread pathogen, which causes infectious rhinotracheitis and infectious pustular vulvovaginitis in cattle. Herein, we have studied the effects of TCDD and BHV-1 infection, in Madin-Darby Bovine Kidney (MDBK) cells, alone as well as in association, so as cellular proliferation, apoptosis, and virus replication. We have observed an increase in cell viability of confluent monolayers at low TCDD concentrations. TCDD treated cells demonstrated increased viability compared to controls as evaluated by MTT test. TCDD exposure increased cell proliferation but induced no changes on apoptosis. Cells exposed to TCDD along with BHV-1 showed a dose-dependent increase in cytopathy, represented by ample syncytia formation with the elimination of the cellular sheets and increased viral titer. These results suggest that TCDD increases viral replication in MDBK cells while BHV-1 further decreases viability of TCDD exposed cells. Since very low concentrations (0.01 pg/ml) are sufficient to augment BHV-1 titer, TCDD may contribute to reactivate BHV-1 from latency, leading to recurrent disease and increase virus transmission. 相似文献
108.
Toxicology of vanadium compounds in diabetic rats: The action of chelating agents on vanadium accumulation 总被引:1,自引:0,他引:1
Jose L. Domingo Mercedes Gomez Domenec J. Sanchez Juan M. Llobet Carl L. Keen 《Molecular and cellular biochemistry》1995,153(1-2):233-240
The possible use of vanadium compounds in the treatment of diabetic patients is now being evaluated. However, previously to establish the optimal maximum dose for diabetes therapy, it should be taken into account that vanadium is a highly toxic element to man and animals. The toxic effects of vanadium are here reviewed. The tissue vanadium accumulation, which would mean an additional risk of toxicity following prolonged vanadium administration is also discussed. Recently, it has been shown that coadministration of vanadate and TIRON, an effective chelator in the treatment of vanadium intoxication, reduced the tissue accumulation of this element, decreasing the possibility of toxic side effects derived from chronic vanadium administration without diminishing the hypoglycemic effect of vanadium. However, previously to assess the effectiveness of this treatment in diabetic patients, a critical reevaluation of the antidiabetic action of vanadium and its potential toxicity is clearly needed. 相似文献
109.
Uncaria rhynchophylla (Gouteng) is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China. In this study, the ethyl acetate (EtOAc) part of U. rhynchophylla was revealed with protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Subsequent investigation on the EtOAc part yielded one new triterpenoid, 3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid (1) and four known ones, 3β,6β,19α-trihydroxyurs-12-en-28-oic acid (2), 2-oxopomolic acid (3), 3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid (4) and sumaresinolic acid (5). The structure of compound 1 was determined by extensive HRESIMS, IR, 1D and 2D NMR spectroscopic analyses. Two ursane-type triterpenoids (2 and 3) showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7 μM. The enzyme kinetic study suggested that compounds 2 and 3 were mix-type inhibitors on PTP1B with Ki values of 15.6 and 132.5 μM. This investigation manifests the antidiabetic potency of U. rhynchophylla with triterpenoids as the active constituents. 相似文献
110.
This study estimates the effects of welfare reform in the 1990s, which permanently restructured and contracted the cash assistance system in the U.S., on food insecurity—a fundamental form of material hardship—of the next generation of households. An implicit goal underlying welfare reform was the disruption of an assumed intergenerational transmission of disadvantage; however, little is known about the effects of welfare reform on the well-being of the next generation of adults. Using intergenerational data from the Panel Study of Income Dynamics and a variation on a difference-in-differences framework, this study exploits 3 sources of variation in childhood exposure to welfare reform: (1) risk of exposure across birth cohorts; (2) variation of exposure within cohorts because different states implemented welfare reform in different years; and (3) variation between individuals with the same exposure who were more likely and less likely to rely on welfare. We found that exposure to welfare reform led to decreases in food insecurity of the next generation of households, by about 10% for a 5-year increase in exposure, with stronger effects for individuals exposed for longer durations during childhood, individuals exposed in early childhood (0–5 years), and women. We also found smaller favorable effects for individuals whose mothers had less than a high school education, indicating that in terms of food insecurity, welfare reform led to relative disadvantages among the most disadvantaged and thus could be exacerbating socioeconomic and health inequalities. 相似文献