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排序方式: 共有4345条查询结果,搜索用时 31 毫秒
941.
Hassan El-Demarawy Samir El-Sahwi Mokhtar Toppozada 《Prostaglandins & other lipid mediators》1977,14(3)
Termination of pregnancy in missed abortion and intra-uterine fetal death was accomplished using vaginal suppositories of 20 mg PGE2 in 31 cases and the results were compared with oxytocin induction (with or without estrogen pre-treatment) in 17 cases at the doses routinely used in our hospital. The PG suppositories proved much more superior (96.7%) than oxytocin (47.7%), but induced a higher rate of side effects. The latter were not serious and were generally tolerated by the patients. There was a positive correlation between duration of fetal retention in utero and the induction expulsion time. The over all patient acceptance of the method was quite favourable and the approach appears to be a definite advance towards management of these cases. 相似文献
942.
943.
Daoud W. Bishy Samuel E. Megalla Mervat M. A. Soliman Hassan M. Abdel-Fattah 《Plant and Soil》1981,60(2):301-307
Summary The simple lipids ofSclerotium cepivorum, the causal agent of white rot of onion and nine other fungal species of the same class were investigated.
The fatty acid composition of the simple lipids of these fungi were determined by GLC. The main fatty acids common to these
fungal species were C16 (saturated) and C18 (unsaturated) acids. The sterol fraction was isolated by column chromatography and its components were detected by GLC and
mass spectrometry. Ergosterol and γ-Ergostenol were found mostly in all fungal species under investigation. However, two fungal
species namelyAlternaria alternata andScolecobasidium constrictum showed no Ergosterol. 相似文献
944.
Genetica - This study aimed to investigate the effects of incidence rate, heritability, and polygenic variance on the statistical power of genome-wide association studies (GWAS) for threshold... 相似文献
945.
Rezakhani Leila Motesharezadeh Babak Tehrani Mohammad Mehdi Etesami Hassan Hosseini Hossein Mirseyed 《Plant and Soil》2022,477(1-2):259-280
Plant and Soil - It is known that the single and combined use of phosphate-solubilizing bacteria (PSB) and silicon (Si) have the potential to improve the uptake of phosphorus (P) by plants... 相似文献
946.
Mahmoud F. Seleiman Muhammad Talha Aslam Bushra Ahmed Alhammad Muhammad Umair Hassan Rizwan Maqbool Muhammad Umer Chattha Imran Khan Harun Ireri Gitari Omer S. Uslu Rana Roy Martin Leonardo Battaglia 《Phyton》2022,91(4):667-694
Salinity stress is a major threat to global food production and its intensity is continuously increasing because of
anthropogenic activities. Wheat is a staple food and a source of carbohydrates and calories for the majority of
people across the globe. However, wheat productivity is adversely affected by salt stress, which is associated with
a reduction in germination, growth, altered reproductive behavior and enzymatic activity, disrupted photosynthesis, hormonal imbalance, oxidative stress, and yield reductions. Thus, a better understanding of wheat (plant)
behavior to salinity stress has essential implications to devise counter and alleviation measures to cope with salt
stress. Different approaches including the selection of suitable cultivars, conventional breeding, and molecular
techniques can be used for facing salt stress tolerance. However, these techniques are tedious, costly, and
labor-intensive. Management practices are still helpful to improve the wheat performance under salinity stress.
Use of arbuscular mycorrhizal fungi, plant growth-promoting rhizobacteria, and exogenous application of phytohormones, seed priming, and nutrient management are important tools to improve wheat performance under
salinity stress. In this paper, we discussed the effect of salinity stress on the wheat crop, possible mechanisms to
deal with salinity stress, and management options to improve wheat performance under salinity conditions. 相似文献
947.
Md. Shamsul Arefin Md. Ariful Islam Md. Mokhlesur Rahman Md. Abdul Alim Sabry Hassan Mahmoud F. K. Soliman Mohamed M. Hassan Rajan Bhatt Akbar Hossain 《Phyton》2022,91(2):439-469
Sugarcane is one of the major important sugar yielding crops in Bangladesh. As an exhaustive crop, sugarcane removes a huge amount of plant nutrients from the soil. However, the combined use of organic and inorganic fertilizers can be a good approach to deal with nutrient depletion and promote sustainable crop production as well as improve soil health. Therefore, an attempt was made to identify the most fruitful and profitable integrated nutrient management on the aspects of growth, yield and quality of sugarcane in two consecutive growing seasons. Seven treatments: T1 = Control, T2 = 165:55:120:30:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T3 = Poultry Litter (PL) at 5 t ha−1 + 95:51:87:9:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T4 = Cow Dung (CD) at 15 t ha−1 + 36:52:60:17:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T5 = Press Mud (PM) at 15 t ha−1 + 10:50:43:0:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T6 = Mustard Oil Cake (MOC) at 0.5 t ha−1 + 140:54:115:25:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1 and T7 = GM (Green Manure) at 5 t ha−1 + 140:53:100:28:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1 were used in this experiment. Two years data showed that treatment T3 produced the maximum amount of tillers, total dry matter yield, millable sugarcane, cane yield and sugar yield, followed by the T4 treatment. The highest stalk heights were recorded in the T3 treatment, which was statistically similar to all other treatments except T1 and T2. The juice quality parameters viz., brix and pol in cane were found significant in treatment T3 while the highest purity was obtained in the T7 treatment. All the data of Jaggery (goor) quality parameters, the highest sucrose content, color transmittance, Jaggery (goor) recovery and the lowest ash content of Jaggery (goor) were observed in the T3 treatment, which was statistically similar to the T4 treatment in both seasons. The highest cost of production was obtained from the T6 treatment while the highest gross return, net return and BCR were recorded in the T3 treatment. No significant changes were found in one cycle of sugarcane in initial and post-harvest soil characteristics viz., pH, organic carbon, total N, and available P, K and S contents due to integrated use of different fertilizer packages. From the experimental findings, it was concluded that treatment T3 followed by T4 treatment would be the better productive and profitable integrated nutrient management technology for ensuring higher yields and quality of sugarcane without soil fertility degradation in the High Ganges River Floodplain soils. 相似文献
948.
Drought stress (DS) is one of the most critical environmental abiotic stresses for wheat production in the arid environments. Selection of high-yielding genotypes tolerant to DS can play a significant role in mitigation the negative impacts associated with DS. In the present study, generation means analysis (GMA) was used to study the performance of two crosses under well irrigation (WI) and deficit irrigation [cross I (Line 44 × Shandweel-1) and cross II (Line 20 × Sakha 93)]. Significant differences were observed for days to heading (DH), days to maturity (DM), plant height (PH), spike length (SL), number of spikes per plant (NS/P), number of grains per spike (NG/S), thousand-grain weight (TGW), grain yield per plant (GY/P), and proline content (PC) in the six populations of the two crosses within each irrigation level. Cross II had early maturity and the highest PC, NS/P, TGW, and GY/P regardless of the irrigation level. Cross I showed positive significant relative heterosis and heterobeltiosis for GY/P under the two irrigation levels. The inheritance of characters of cross I revealed additive, dominant, and epistatic effects, which varied with trait and stress. Additive genetic effects predominated in DH, SL, and PC, while non- additive were found in DM, NS/P, NG/S, and GY/P. Narrow-sense heritability estimates (h2n) were high for DH and PC, moderate to high for PH and SL, moderate for DM, NG/S, NS/P, and TGW, and low for GY/P. Based on different drought indices the populations BC1, BC2, F1, and P1 of cross II and BC1 of cross I were more tolerant to drought stress. Therefore, PC, TGW and DH can be used as selection indicators to improve wheat for drought tolerance in early generations and other yield components traits in late generations. The second cross (Line 20 × Sakha 93) shows promise and is of interest to a drought tolerance breeding program, where wheat breeders can use recombinant breeding strategies to construct desirable drought stress genes. Correlation and path coefficient revealed that TGW and PC were the main contributor in grain yield in both environments. 相似文献
949.
Hua-Feng Wang Xiaoting Xu Xia-Lan Cheng Yunpeng Liu Ao Luo Tong Lyu Wen-Long Wang Mir Muhammad Nizamani Zhiheng Wang 《Journal of Plant Ecology》2022,15(6):1142
Understanding large-scale patterns of biodiversity and their drivers remains central in ecology. Many hypotheses
have been proposed, including hydrothermal dynamic hypothesis, tropical niche conservatism hypothesis, Janzen’s
hypothesis and a combination model containing energy, water, seasonality and habitat heterogeneity. Yet, their
relative contributions to groups with different lifeforms and range sizes remain controversial, which have limited
our ability to understand the general mechanisms underlying species richness patterns. Here we evaluated how
lifeforms and species range sizes influenced the relative contributions of these three hypotheses to species richness
patterns of a tropical family Moraceae. The distribution data of Moraceae species at a spatial resolution of 50km
×50 km and their lifeforms (i.e. shrubs, small trees and large trees) were compiled. The species richness patterns
were estimated for the entire family, different life forms and species with different range sizes separately. The effects
of environmental variables on species richness were analyzed, and relative contributions of different hypotheses
were evaluated across life forms and species range size groups. The species richness patterns were consistent across
different species groups and the species richness was the highest in Sichuan, Guangzhou and Hainan provinces,
making these provinces the hotspots of this family. Climate seasonality is the primary factor in determining richness
variation of Moraceae. The best combination model gave the largest explanatory power for Moraceae species
richness across each group of range size and life forms followed by the hydrothermal dynamic hypothesis, Janzen’s
hypothesis and tropical niche conservatism hypothesis. All these models has a large shared effects but a low
independent effect (< 5%), except rare species. These findings suggest unique patterns and mechanisms underlying
rare species richness and provide a theoretical basis for protection of the Moraceae species in China. 相似文献
950.
Ahmad Tahir Ali Sher Shah Syed Bilal Hussian Khan Inam Ullah Hassan Muhammad Abul Ullah Syed Irfan 《Cluster computing》2022,25(4):2403-2415
Cluster Computing - The device-to-device D-2-D Communication empowered Cloud Radio Access Network (CRAN) which is examined to be auspicious system model, gives energy efficiency and high data rate.... 相似文献