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排序方式: 共有708条查询结果,搜索用时 46 毫秒
91.
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Timothy H Rainer Peter A Cameron DeVilliers Smit Kim L Ong Alex Ng Wing Hung David Chan Po Nin Anil T Ahuja Louis Chan Yik Si Joseph J Y Sung 《BMJ (Clinical research ed.)》2003,326(7403):1354-1358
Objectives To determine the clinical and radiological features of
severe acute respiratory syndrome (SARS) and to evaluate the accuracy of the
World Health Organization''s guidelines on defining cases of SARS.Design Prospective observational study.Setting A newly set up SARS screening clinic in the emergency
department of a university hospital in Hong Kong''s New Territories.Participants 556 hospital staff, patients, and relatives who
attended the screening clinic and who had had contact with someone with
SARS.Main outcome measure Number of confirmed cases of SARS.Results Of the 556 people, 141 were admitted to hospital, and 97 had
confirmed SARS. Fever, chills, malaise, myalgia, rigor, loss of appetite,
vomiting, diarrhoea, and neck pain but not respiratory tract symptoms were
significantly more common among the 97 patients than among the other patients.
The overall accuracy of the WHO guidelines for identifying suspected SARS was
83% and their negative predictive value was 86% (95% confidence interval 83%
to 89%). They had a sensitivity of 26% (17% to 36%) and a specificity of 96%
(93% to 97%).Conclusions Current WHO guidelines for diagnosing suspected SARS may
not be sufficiently sensitive in assessing patients before admission to
hospital. Daily follow up, evaluation of non-respiratory, systemic symptoms,
and chest radiography would be better screening tools. 相似文献
94.
95.
Hui‐Min Wang Yan‐Ping Shih Su‐Ming Hu Wen‐Tsung Lo Hui‐Min Lin Shih‐Shiu Ding Hsin‐Chi Liao Po‐Huang Liang 《Biotechnology progress》2009,25(6):1582-1586
To quickly find an optimal expression system for recombinant protein production, a set of vectors with the same restriction sites were constructed for parallel cloning of a target gene and recombinant protein production in prokaryotic and eukaryotic expression systems, simultaneously. These vectors include nucleotide sequences encoding protein tags and protease recognition sites for tag removal, followed by the cloning sites 5′‐EcoRI/3′‐XhoI identical in these vectors for ligating with the sticky‐end PCR product of a target gene. Our vectors allow parallel gene cloning and protein production in multiple expression systems with minimal cloning effort. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
96.
Mei Wang Yok Moi Khoo Jin Zhou Patrick Casey How Sung Lee 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(5-6):553-557
Cysmethynil, a newly identified small molecule inhibitor of isoprenylcysteine carboxylmethyl transferase (Icmt) is involved in the post-translational modification of CaaX proteins. Cysmethynil causes cell death in many human cancer cells in vitro, and inhibits tumor growth in the xenograft mouse model in vivo. A HPLC method for the quantification of cysmethynil in mouse plasma was developed and validated. The lower limit of quantification of this method was 0.01 μg/ml. Inter- and intra-day variability ranged from 0.38–8.5% and accuracy was between 86% and 98%. This sensitive method was used to quantify cysmethynil in plasma of mice after intraperitoneal dosing for preliminary pharmacokinetic studies. 相似文献
97.
D. Esmenjaud R. Voisin C. Van Ghelder N. Bosselut B. Lafargue M. Di Vito E. Dirlewanger J. L. Poëssel M. Kleinhentz 《Tree Genetics & Genomes》2009,5(2):279-289
Sources of resistance in Prunus spp. exhibit different spectra to the root-knot nematodes (RKN) Meloidogyne incognita, Meloidogyne javanica and Meloidogyne floridensis. In this Prunus genus, two dominant genes, Ma with a complete spectrum from the heterozygous Myrobalan plums P.2175 and P.2980 (section Euprunus; subgenus Prunophora) and RMia with a more restricted spectrum from the peaches Nemared and Shalil (subgenus Amygdalus), have been identified. This study characterizes the resistance spectra of interspecific crosses involving (1) previous Myrobalan
and peach sources, (2) two Alnem almonds (subgenus Amygdalus) resistant to M. javanica, and (3) the apricot A.3923, representing a species considered RKN-resistant (section Armeniaca; Prunophora). For both latter species, genetic data could be obtained through F1 crosses with genetically characterized Myrobalans that
conferred their rooting ability for clonal multiplication of the hybrids and permitted their simultaneous evaluation to the
three RKN. Crosses involving either Ma or RMia or both generated the expected resistance spectra. Nemared confirmed the species-specific resistance to M. incognita conferred by RMia. This rootstock, also previously considered resistant to M. javanica, was susceptible to the M. javanica isolate used, what illustrates an isolate-specific resistance to this species. Alnem accessions were shown homozygous resistant
to M. javanica. In the progeny P.2980 × A.3923, Ma markers allowed to distinguish resistant individuals carrying that gene from resistant individuals lacking it. Distribution
of non-Ma individuals in this cross suggested, in the apricot parent, (1) the absence of a major gene allelic to Ma and (2) the presence of a non RKN specific polygenic resistance. 相似文献
98.
Po‐Shiuan Hsieh Jong‐Shiaw Jin Chih‐Fan Chiang Pei‐Chi Chan Chih‐Hao Chen Kuang‐Chung Shih 《Obesity (Silver Spring, Md.)》2009,17(6):1150-1157
The aim was to examine the role of cyclooxygenase (COX)‐2‐mediated inflammation in the development of obese linked insulin resistance and fatty liver. The rats were fed separately regular diet (CONT), high‐fat diet (HFD) ad libitum, or energy restrictedly for 12 weeks. Rats fed HFD ad libitum were further divided into three subgroups co‐treated with vehicle (HFa), or a selective COX‐2 inhibitor celecoxib (HFa‐Cel) or mesulid (HFa‐Mes). Euglycemic hyperinsulinemic clamp (EHC) experiment was performed at the end of study. Another set of rats with similar grouping was further divided into those with a 4, 8, or 12‐week intervention period for hepatic sampling. Body weight was increased significantly and similarly in HFa, HFa‐Cel, and HFa‐Mes. Time‐dependent increases in plasma insulin, glucose, 8‐isoprostanes, leptin levels, homeostasis model assessment of insulin resistance (HOMA‐IR) and hepatic triglyceride contents shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. During EHC period, the reduction in stimulation of whole body glucose uptake, suppression of hepatic glucose production and metabolic clearance rate of insulin shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. The enhanced COX‐2 and tumor necrosis factor‐α (TNF‐α) but attenuated PPAR‐γ and C/EBP‐α mRNA expressions in epididymal fat shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. The increases in average cell size of adipocytes and CD68 positive cells shown in HFa were also significantly reversed in HFa‐Cel and HFa‐Mes. Our findings suggest that COX‐2 activation in fat inflammation is important in the development of insulin resistance and fatty liver in high fat induced obese rats. 相似文献
99.
Po‐Cheng Chen Kuo‐Ping Chiang Sheng‐Fang Tsai 《The Journal of eukaryotic microbiology》2017,64(5):579-587
The number of somatic kineties in Pelagostrobilidium ranges from 4 to 6 according to the present state of knowledge. This study investigates Pelagostrobilidium liui n. sp. using live observation, protargol stain, and small subunit rDNA data sequencing. Pelagostrobilidium liui n. sp. is characterized by having a spherical‐shaped body, four somatic kineties, with kinety 2 spiraled around the left side of body, about six elongated external membranelles, and invariably no buccal membranelle. It differs from its most similar congener, Pelagostrobilidium minutum Liu et al., 2012 , in (i) cell shape; (ii) macronucleus width; (iii) oral apparatus; (iv) anterior orientation of kinety 2; (v) location where kinety 2 commences; (vi) arrangement of kinety 1; (vii) distance between the anterior cell end and the locations where kineties commence; and (viii) the presence of 12 different bases (including two deletions) in the small subunit rDNA sequences. The diagnosis of P. minutum Liu et al., 2012 is also improved to include the following new characteristics: invariably four somatic kineties; kineties 2 and 4 alone commence at the same level; kinety 2 originates from right anterior cell half on ventral side, extends sinistrally posteriorly, over kinety 1, around left posterior region, terminates near posterior cell end on dorsal side; kinety 1 commences below anterior third of kinety 2. 相似文献
100.
Chan Jin Park Guanglin Chen Yongbum Koo Po‐Ching P. Lin Joseph A. Cacioppo Hailey Prohaska CheMyong J. Ko 《Genesis (New York, N.Y. : 2000)》2017,55(12)
Two estrogen receptors, ESR1 and ESR2, are responsible for the classical actions of estrogens in mammalian species. They display different spatiotemporal expression patterns and nonoverlapping functions in various tissues and physiological conditions. In this study, a novel knock‐in mouse line that expresses codon‐improved Cre recombinase (iCre) under regulation of the natural Esr1 promoter (Esr1–iCre) was developed. Functional characterization of iCre expression by crossing them with reporter lines (ROSA26‐lacZ or Ai9‐RFP) showed that iCre is faithfully expressed in Esr1‐lineage cells. This novel transgenic mouse line will be a useful animal model for lineage‐tracing Esr1‐expressing cells, selective gene ablation in the Esr1‐lineage cells and for generating global Esr1 knockout mice. 相似文献