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381.
A co-culture of bacteria responsible for the conversion of butyrate to methane and CO2 was isolated from a cattle-waste treatment plant. The non-methanogenic partner of the co-culture was Syntrophomonas wolfei and the methanogenic partner was Methanobacterium formicicum. Although butyrate degradation occurred at pH<6.0 and below 45°C, methanogenesis was observed at pH>6.5 and above 40°C. 相似文献
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ABSTRACT: Randomized controlled trials are the principal means of establishing the efficacy of drugs. However pre-marketing trials are limited in size and duration and exclude high-risk populations. They have limited statistical power to detect rare but potentially serious adverse events in real-world patients. We summarize the principal methodological challenges in the reporting, analysis and interpretation of safety data in clinical trials using recent examples from systematic reviews. The principle challenges include the lack of an evidentiary gold standard, the limited statistical power of randomized controlled trials and resulting type 2 error, the lack of adequate ascertainment of adverse events and limited generalizability of safety trials that exclude high risk patients. We discuss potential solutions to these challenges. Evaluation of drug safety requires careful examination of data from heterogeneous sources. Meta-analyses of drug safety should include appropriate statistical methods and assess the optimal information size to avoid type 2 errors. They should evaluate outcome reporting biases and missing data to ensure reliable and accurate interpretation of findings. Regulatory and academic partnerships should be fostered to provide an independent and transparent evaluation of drug safety. 相似文献
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Summary A field experiment was conducted to study the effect of Rhizobium inoculation, nitrogen and simazine application, individually
and in combination, on yield and quality of Bengal gram. Application of nitrogen and simazine, and seed inoculation with Rhizobium
increased the grain yield significantly. The combined treatment of Rhizobium, simazine and nitrogen increased the grain yield
to the extent of 70 per cent over control. Application of simazine increased the methionine content. re]19760609 相似文献
386.
Abstract Sea sediments in tropical regions have been less studied for methanogenesis and methanogens present therein. Three species of methanogens viz. Methanobacterium bryantii, Methanococcus voltae and Methanosarcina barkeri were isolated from Arabian sea sediments collected near the west coast of India. Maximum methane was formed by M. voltae at 3.0% (w/v) NaCl and other two methanogens at 0.06% (w/v) NaCl. M. bryantii and M. barkeri tolerated 2.5 and 3.0% (w/v) NaCl respectively due to which these methanogens must have survived in salt conditions of the sea sediments. 相似文献
387.
M. S. Kadam A. B. Chaudhari S. B. Chincholkar 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2012,6(3):249-254
Optical fluorescence-quenching-based biosensing cell is described and optimization of covalent binding of highly selective natural iron-chelating peptide secreted by bacteria is suggested. Pyoverdin biosynthesized by Pseudomonas monteilii and having 70% iron chelating activity was immobilized on amino alkylated controlled pore glass (CPG) and cross-linked with glutaraldehyde (2.5%, 28°C, 30 min). The pyoverdin-CPG immobilization was confirmed using fluorescence microscopic images (excitation range, 465–495 nm) for bright green fluorescence and by FTIR spectrum stretching at 3406.4 cm−1 for amino group. The pyoverdin loading capacity of activated CPG matrix was 25 mg g−1 of CPG and its rinsing analysis (leaking profile of the immobilized peptide vs. washing) detected negligible (2–3 μg) pyoverdin in the second wash. 相似文献
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