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991.
Wim H. J. Kruit Paul I. M. Schmitz Gerrit Stoter 《Cancer immunology, immunotherapy : CII》1999,48(6):331-335
Renal dysfunction is a frequently encountered adverse event following treatment with high-dose interleukin-2 (IL-2). Information
about parameters predicting the severity of IL-2-associated renal function abnormalities is limited. In this study the role
of possible risk factors in the development of high-dose IL-2-associated acute and long-term renal dysfunction was investigated.
A total of 72 patients, who were treated with a regimen consisting of IL-2 (18 MIU m−2 day−1 by continuous infusion), interferon α (IFNα; 5 MIU m−2 day−1, intramuscularly) and lymphokine-activated killer (LAK) lymphocytes, were analysed. Serum creatinine measurements were performed
daily during treatment, weekly between courses and monthly during follow-up. Pre-and posttreatment 24-h urine samples were
collected for calculation of creatinine clearances. Renal dysfunction was observed in 97% of patients. Grade 1 dysfunction
(according to WHO criteria) was observed in 20 patients (28%), grade 2 in 37 (51%), grade 3 in 13 (14%) and grade 4 in 0 (0%).
Renal dysfunction was reversible in more than 90% of patients. Only 6 patients (8%) suffered a certain amount of permanent
function loss. More severe acute renal dysfunction occurred in patients who were experiencing hypertension prior to treatment,
those who suffered sepsis during treatment and in men than in women. Sepsis was also associated with irreversible function
loss. Other variables such as age, performance status, diabetes mellitus, interval between nephrectomy and start of IL-2 therapy
and hypotension during treatment were not important. In conclusion, with high-dose IL-2, renal dysfunction develops in almost
every patient and such abnormalities are mostly reversible. Predictors for severe acute renal dysfunction are pre-existing
hypertension, sepsis and sex. A septic episode also carries a risk of permanent damage.
Received: 10 December 1998 / Accepted: 20 May 1999 相似文献
992.
目的 观察国产降纤酶对急性脑梗死的溶栓治疗效果。方法 随机选择临床确诊的急性脑梗死患者 ,发病在 3~ 1 2 h以内者 5 6例 ,给予降纤酶静脉溶栓治疗 ,采用加拿大人神经病学评分在 2 4 h内明显增加者 37例 ,占 6 6 % ;4 8h内明显增加者 4 2例 ,占 75 % ;72 h内明显增加者 5 4例 ,占 96 %。 2例病人计分无明显变化 ,占 4 %。结论 国产降纤酶对发病 1 2 h以内的急性脑梗死病人临床溶栓效果良好。 相似文献
993.
Carl W. Mize Kenneth J. Koehler Michael E. Compton 《In vitro cellular & developmental biology. Plant》1999,35(2):122-126
Summary The paper is the second of two papers about statistical considerations that researchers should make while doing in vitro plant
biology research. The first paper focused on aspects from developing a plan to do research through the collection of data.
This paper continues with information about editing data, handling outliers, analyzing quantitative and qualitative data,
comparing treatment means, preparing graphs and tables, and presenting results. 相似文献
994.
杀虫剂轮用和混用对害虫种群抗性演化的影响 总被引:11,自引:1,他引:10
杀虫剂轮用和混用是当前害虫抗药性治理中最常采用的两种用药策略。该文用抗性模型和室内试验对轮用和混用延缓害虫抗性演化的效果及轮用最佳间隔期问题作了研究。模型模拟结果表明,在延缓害虫抗性演化方面轮用和混用对抗性演化的影响主要取决于杀虫剂作用强度、抗性基因型个体的适合度大小和杀虫剂混用后的毒理效应类型。两种杀虫剂轮用时,轮用间隔期以1(即两种杀虫剂隔次施用)为佳。以模型昆虫小菜蛾Plutella xylostella在室内试验结果表明,氰戊菊酯单用(I)及与杀虫单轮用(II)和混用(1∶1)(III)连续处理8代后,抗性个体频率为0.01的小菜蛾种群其3龄幼虫对氰戊菊酯的抗性分别上升了75.87(I)、28.67(II)和58.72(III)倍,与模型模拟结果表现出较好的一致性。据此,作者认为抗性模型可用于预测害虫抗性演化和评价抗性治理策略。 相似文献
995.
Induction of embryogenesis from isolated apple microspores 总被引:2,自引:0,他引:2
We report, for the first time, the induction of embryogenesis and plant formation from isolated apple (Malus domestica Borkh.) microspores in vitro. Different isolation techniques were tested and an optimized protocol was elaborated. Furthermore,
the influence of the induction medium and starvation treatment, using different starvation material, temperatures and time,
were studied. In addition to embryo induction, the number of multicellular structures per divided microspores was found to
be a suitable parameter of assessment and could be used in earlier stages during microspore culture. Although the number of
embryos induced in these first experiments is low, the best frequency of embryo induction was shown to be at least twice as
efficient as that obtained by anther culture.
Received: 9 September 1998 / Revision received: 22 December 1998 / Accepted: 12 January 1999 相似文献
996.
野生朱鹮的种群数量和分布现状 总被引:2,自引:0,他引:2
2012年9-10月,我们对野生朱鹮(Nipponia nippon)的分布区和潜在分布区进行了调查,共发现其游荡期夜宿地23个,其中20个有朱鹮夜宿,分布在洋县(16个)、宁陕县(3个)和城固县(1个)。对这些夜宿地进行了的同步调查,共统计到野生朱鹮1 090只,其中97.2%分布在洋县境内。最大的夜宿集群数量为184只,集群数量超过40只的夜宿地共11个,累计停歇的朱鹮占总数的91.7%,表明野生朱鹮在游荡期有趋于集结较大群体夜宿的习性。朱鹮野生种群中当年出生的幼鸟占19.0%,据此估算,截至秋季朱鹮幼鸟的存活率约为67.2%。加强对保护区以外,尤其是野生朱鹮新扩散地区的的保护管理,将促进野生朱鹮种群的扩散,进一步增加这一濒危物种抵御风险的能力。 相似文献
997.
Mai Soliman Lamar Alshamrani Basma Yahya Ghadah Alajlan Alhanoof Aldegheishem Elzahraa Eldwakhly 《Saudi Journal of Biological Sciences》2021,28(11):6523-6531
The gold standard for restoring Endodontically Treated Teeth (ETT) with successful clinical longevity requires having minimal invasive preparations and maximal tissue conservation. Many dentists still consider hybrid post/core/crown to be the first choice for restoring ETT. Endocrown is a viable alternative treatment modality to hybrid post/core/crown. This study aims to assess the proper judgment of dentists working in Riyadh, Saudi Arabia on the use of monolithic endocrown versus hybrid post/core/crown for restoring ETT. The IRB of Princess Nourah Bint Abdulrahman University (PNU) Institutional Review Board reviewed this study. The questionnaire was validated and electronically distributed. The participants were pre-informed that their responses are completely anonymous and used for professional purposes only. The questionnaire surveyed dentists working in Riyadh, Saudi Arabia, about their preference for different ETT restorative modalities at various clinical scenarios. Data were analyzed using One-way ANOVA and t-test. All P-values of < 0.05 were considered statistically significant. A total of 275 responses were collected; 61.45% were females and 38.55% males. 56% of them were general practitioners, while 16% were consultants. Prefabricated post/core was the most preferred technique among the participants (18.55%), followed by endocrown (12.36%), and lastly, cast post/core (8.73%). The amount of remaining tooth structure was the most influential in the treatment selection (30.18%), followed by the presence or absence of 1–2 mm ferrule (17.82%). Interocclusal space (12.36%) was the least influential factor. Endocrown recorded 63.27% as the most preferred line of treatment in case of insufficient inter-occlusal space. 40.36% preferred endocrown for patients with occlusal risk factors. The amount of the remaining tooth structure and the tooth position significantly affect the treatment options of the participants. Endocrown was the most preferred treatment modality for restoring ETT for patients with occlusal consideration. 相似文献
998.
Nonideal nest box selection by tree swallows breeding in farmlands: Evidence for an ecological trap?
Animals are expected to select a breeding habitat using cues that should reflect, directly or not, the fitness outcome of the different habitat options. However, human‐induced environmental changes can alter the relationships between habitat characteristics and their fitness consequences, leading to maladaptive habitat choices. The most severe case of such nonideal habitat selection is the ecological trap, which occurs when individuals prefer to settle in poor‐quality habitats while better ones are available. Here, we studied the adaptiveness of nest box selection in a tree swallow (Tachycineta bicolor) population breeding over a 10‐year period in a network of 400 nest boxes distributed along a gradient of agricultural intensification in southern Québec, Canada. We first examined the effects of multiple environmental and social habitat characteristics on nest box preference to identify potential settlement cues. We then assessed the links between those cues and habitat quality as defined by the reproductive performance of individuals that settled early or late in nest boxes. We found that tree swallows preferred nesting in open habitats with high cover of perennial forage crops, high spring insect biomass, and high density of house sparrows (Passer domesticus), their main competitors for nest sites. They also preferred nesting where the density of breeders and their mean number of fledglings during the previous year were high. However, we detected mismatches between preference and habitat quality for several environmental variables. The density of competitors and conspecific social information showed severe mismatches, as their relationships to preference and breeding success went in opposite direction under certain circumstances. Spring food availability and agricultural landscape context, while related to preferences, were not related to breeding success. Overall, our study emphasizes the complexity of habitat selection behavior and provides evidence that multiple mechanisms may potentially lead to an ecological trap in farmlands. 相似文献
999.
Siyang Xia Hany K. M. Dweck Joel Lutomiah Rosemary Sang Carolyn S. McBride Noah H. Rose Diego Ayala Jeffrey R. Powell 《Ecology and evolution》2021,11(22):16327
Adaptations to anthropogenic domestic habitats contribute to the success of the mosquito Aedes aegypti as a major global vector of several arboviral diseases. The species inhabited African forests before expanding into domestic habitats and spreading to other continents. Despite a well‐studied evolutionary history, how this species initially moved into human settlements in Africa remains unclear. During this initial habitat transition, African Ae. aegypti switched their larval sites from natural water containers like tree holes to artificial containers like clay pots. Little is known about how these natural versus artificial containers differ in their characteristics. Filling this knowledge gap could provide valuable information for studying the evolution of Ae. aegypti associated with larval habitat changes. As an initial effort, in this study, we characterized the microenvironments of Ae. aegypti larval sites in forest and domestic habitats in two African localities: La Lopé, Gabon, and Rabai, Kenya. Specifically, we measured the physical characteristics, microbial density, bacterial composition, and volatile chemical profiles of multiple larval sites. In both localities, comparisons between natural containers in the forests and artificial containers in the villages revealed significantly different microenvironments. We next examined whether the between‐habitat differences in larval site microenvironments lead to differences in oviposition, a key behavior affecting larval distribution. Forest Ae. aegypti readily accepted the artificial containers we placed in the forests. Laboratory choice experiments also did not find distinct oviposition preferences between forest and village Ae. aegypti colonies. These results suggested that African Ae. aegypti are likely generalists in their larval site choices. This flexibility to accept various containers with a wide range of physical, microbial, and chemical conditions might allow Ae. aegypti to use human‐stored water as fallback larval sites during dry seasons, which is hypothesized to have initiated the domestic evolution of Ae. aegypti. 相似文献
1000.