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841.
842.
Delivering value from sperm proteomics for fertility 总被引:1,自引:0,他引:1
Govindaraju A Dogan S Rodriguez-Osorio N Grant K Kaya A Memili E 《Cell and tissue research》2012,349(3):783-793
Fertilization of an egg by a spermatozoon sets the stage for mammalian development. Viable sperm are a prerequisite for successful fertilization and beyond. Spermatozoa have a unique cell structure where haploid genomic DNA is located in a tiny cytoplasmic space in the head, mitochondria in the midpiece and then the tail, all enclosed by several layers of membrane. Proteins in sperm play vital roles in motility, capacitation, fertilization, egg activation and embryo development. Molecular defects in these proteins are associated with low fertility or in some cases, infertility. This review will first summarize genesis, molecular anatomy and physiology of spermatozoa, fertilization, embryogenesis and then those proteins playing important roles in various aspects of sperm physiology. 相似文献
843.
Abdullah Shehab Abdishakur Abdulle Awad El Issa Jassim Al Suwaidi Nico Nagelkerke 《PloS one》2012,7(10)
Aims
We assessed the effect of fasting during Ramadan on blood pressure (BP), body weight, plasma lipid, and lipoprotein variables among healthy normal individuals.Methods
102 (68% male) multi-ethnic volunteers; mean age ± SD (38.7±10.5 years) were randomly recruited in Al-Ain, United Arab Emirates (UAE), to be investigated before Ramadan, one day after the end of Ramadan, and four weeks after Ramadan. Anthropometric, demographic, fasting plasma total cholesterol (TC), triglyceride (TG), and high density lipoprotein–cholesterol (HDL-C) were measured by standard methods, and Low density lipoprotein-cholesterol (LDL-C) was calculated using Friedewald’s formula.Results
65 subjects completed the study. We found significant and beneficial changes in systolic blood pressure (SBP), body weight, waist circumference (WC), TG, HDL-C and LDL-C, at the end of Ramadan, but not in TC. Further, there was a progressive and significant increase and decrease in HDL-C and LDL-C levels, respectively, four weeks after Ramadan.Conclusions
We observed significant improvements in HDL-C, and LDL-C levels even after four weeks post Ramadan. Ramadan-like fasting may be considered for more effective lipid and lipoprotein control. 相似文献844.
Ramjiawan B Pierce GN Anindo MI Alkukhun A Alshammari A Chamsi AT Abousaleh M Alkhani A Ganguly PK 《Advances in physiology education》2012,36(1):27-33
An important part of training the next generation of physicians is ensuring that they are exposed to the integral role that research plays in improving medical treatment. However, medical students often do not have sufficient time to be trained to carry out any projects in biomedical and clinical research. Many medical students also fail to understand and grasp translational research as an important concept today. In addition, since medical training is often an international affair whereby a medical student/resident/fellow will likely train in many different countries during his/her early training years, it is important to provide a learning environment whereby a young medical student experiences the unique challenges and value of an international educational experience. This article describes a program that bridges the gap between the basic and clinical research concepts in a unique international educational experience. After completing two semester curricula at Alfaisal University in Riyadh, Kingdom of Saudi Arabia, six medical students undertook a summer program at St. Boniface Hospital Research Centre, in Winnipeg, MB, Canada. The program lasted for 2 mo and addressed advanced training in basic science research topics in medicine such as cell isolation, functional assessment, and molecular techniques of analysis and manipulation as well as sessions on the conduct of clinical research trials, ethics, and intellectual property management. Programs such as these are essential to provide a base from which medical students can decide if research is an attractive career choice for them during their clinical practice in subsequent years. An innovative international summer research course for medical students is necessary to cater to the needs of the medical students in the 21st century. 相似文献
845.
Hadi M. Marwani Abdullah M. Asiri Salman A. Khan 《Russian Journal of Bioorganic Chemistry》2012,38(5):533-538
Preparation, characterization, photostability and polarity studies of novel Schiff base dyes using spectroscopic methods were achieved. The Schiff base dyes were prepared by the reaction of salicylalde-hyde/2-hydroxy-l-naphthaldehyde with aminophenazone under microwave irradiation. The spectroscopic (FT-IR, 1H NMR, 13C NMR, Mass) studies and elemental analyses were in good agreement with chemical structure of synthesized compounds. In addition, UV-Vis and fluorescence spectroscopic experiments showed that these dyes are good absorbent and fluorescent. Based on the photostability study of these dyes, minimal to no loss in fluorescence intensities of 4-[(2-hydroxy-benzylidene)-amino]1,5-dimemyl-2-phe-nyl-1,2-dihydro-pyrazol-3-one (D1) (6.14%) and 4-[(2-hydroxy-naphthalen-l-ylmethylene)-amino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (D2) (2.95%) was observed with an increase in the exposure time using time-based fluorescence steady-state experiments. These studies also inferred that these Schiff base dyes have a high photostability against photobleaching. In addition, Dye 2 is found to be more sensitive than Dye 1 to the polarity of the microenvironment provided by different solvents based on the results of fluorescence polarity studies. 相似文献
846.
Background and aim: Polymorphisms of Helicobacter pylori cagA and vacA genes do exist and may contribute to differences in H. pylori infection and gastroduodenal diseases among races in the Malaysian population. This study was conducted to characterize the polymorphisms in H. pylori cagA and vacA in Malaysian population. Methods: A total of 110 H. pylori isolates were genotyped by PCR and sequenced for cagA and PCR‐RFLP for vacA. Results: East Asian cagA was predominantly detected (64.5%), whereas vacA s1m1 and s1m2 alleles were detected in 60.9 and 37.3% of strains, respectively. A statistical association between cagA type with patients’ ethnicity (p < .0001) and age group >50 years old (p = .027) was identified. vacA alleles showed significant association with age group >50 years old (p = .017) and increased neutrophil activity in gastric mucosa (p = .028 and p = .016 for moderate and marked activity, respectively). Further identification of vacA polymorphism revealed that 84% of strains from Malays and Indians showed one RFLP pattern (RFLP‐1), whereas more than one RFLP patterns (RFLP‐2, 3, 4, 5, 6, and 8) were predominantly observed in strains from Chinese (82%) (p < .0001). Increasing severity of gastric inflammation was observed in gastric mucosa infected with strains carrying RFLP‐2, 3, 4, 5, and 6 (p = .037). About 86.6% of H. pylori strains with East Asian cagA were vacA RFLP‐2, 3, 4, 5, 6, and 8, and 88% of Western cagA strains were vacA RFLP‐1 (p < .0001). Chinese and Indians are susceptible to different virulence genotypes of H. pylori, whereas Malays showed a mixed virulence genotypes. Conclusion: Marked differences in the polymorphisms of cagA and vacA were observed among strains in Malaysian population. This provides a new insight into the pathogenicity of H. pylori in multiracial population. 相似文献
847.
Richelle C. Charles Jason B. Harris Michael R. Chase Lauren M. Lebrun Alaullah Sheikh Regina C. LaRocque Tanya Logvinenko Sean M. Rollins Abdullah Tarique Elizabeth L. Hohmann Ian Rosenberg Bryan Krastins David A. Sarracino Firdausi Qadri Stephen B. Calderwood Edward T. Ryan 《PloS one》2009,4(9)
Background
S. Typhi, a human-restricted Salmonella enterica serovar, causes a systemic intracellular infection in humans (typhoid fever). In comparison, S. Typhimurium causes gastroenteritis in humans, but causes a systemic typhoidal illness in mice. The PhoP regulon is a well studied two component (PhoP/Q) coordinately regulated network of genes whose expression is required for intracellular survival of S. enterica.Methodology/Principal Findings
Using high performance liquid chromatography mass spectrometry (HPLC-MS/MS), we examined the protein expression profiles of three sequenced S. enterica strains: S. Typhimurium LT2, S. Typhi CT18, and S. Typhi Ty2 in PhoP-inducing and non-inducing conditions in vitro and compared these results to profiles of phoP−/Q− mutants derived from S. Typhimurium LT2 and S. Typhi Ty2. Our analysis identified 53 proteins in S. Typhimurium LT2 and 56 proteins in S. Typhi that were regulated in a PhoP-dependent manner. As expected, many proteins identified in S. Typhi demonstrated concordant differential expression with a homologous protein in S. Typhimurium. However, three proteins (HlyE, STY1499, and CdtB) had no homolog in S. Typhimurium. HlyE is a pore-forming toxin. STY1499 encodes a stably expressed protein of unknown function transcribed in the same operon as HlyE. CdtB is a cytolethal distending toxin associated with DNA damage, cell cycle arrest, and cellular distension. Gene expression studies confirmed up-regulation of mRNA of HlyE, STY1499, and CdtB in S. Typhi in PhoP-inducing conditions.Conclusions/Significance
This study is the first protein expression study of the PhoP virulence associated regulon using strains of Salmonella mutant in PhoP, has identified three Typhi-unique proteins (CdtB, HlyE and STY1499) that are not present in the genome of the wide host-range Typhimurium, and includes the first protein expression profiling of a live attenuated bacterial vaccine studied in humans (Ty800). 相似文献848.
Samer Al-Kiswany Abdullah Gharaibeh Elizeu Santos-Neto Matei Ripeanu 《Cluster computing》2009,12(2):123-140
Today Graphics Processing Units (GPUs) are a largely underexploited resource on existing desktops and a possible cost-effective
enhancement to high-performance systems. To date, most applications that exploit GPUs are specialized scientific applications.
Little attention has been paid to harnessing these highly-parallel devices to support more generic functionality at the operating
system or middleware level. This study starts from the hypothesis that generic middleware-level techniques that improve distributed
system reliability or performance (such as content addressing, erasure coding, or data similarity detection) can be significantly
accelerated using GPU support.
We take a first step towards validating this hypothesis and we design StoreGPU, a library that accelerates a number of hashing-based
middleware primitives popular in distributed storage system implementations. Our evaluation shows that StoreGPU enables up
twenty five fold performance gains on synthetic benchmarks as well as on a high-level application: the online similarity detection
between large data files.
相似文献
Matei RipeanuEmail: |
849.
Hanan Dahche AbdulShakur Abdullah M. Ben Potters Peter J. Kennelly 《Extremophiles : life under extreme conditions》2009,13(2):371-377
The genomes of virtually all free-living archaeons encode one or more deduced protein-serine/threonine/tyrosine kinases belonging
to the so-called eukaryotic protein kinase superfamily. However, the distribution of their cognate protein-serine/threonine/phosphatases
displays a mosaic pattern. Thermoplasma volcanium is unique among the Archaea inasmuch as it is the sole archaeon whose complement of deduced phosphoprotein phosphatases includes a member of the PPM-family
of protein-serine/threonine phosphatases—a family that originated in the Eucarya. A recombinant version of this protein, TvnPPM, exhibited protein-tyrosine phosphatase in addition to its predicted protein-serine/threonine
phosphatase activity in vitro. TvnPPM is the fourth member of the PPM-family shown to exhibit such dual-specific capability, suggesting that the ancestral
versions of this enzyme exhibited broad substrate specificity. Unlike most other archeaons, the genome of T. volcanium lacks open reading frames encoding stereotypical protein-tyrosine phosphatases. Hence, the dual-specificity of TvnPPM may
account for its seemingly aberrant presence in an archaeon. 相似文献
850.
Yusmazura Zakaria Asmah Rahmat Azimahtol Hawariah Hawariah Lope Pihie Noor Rain Abdullah Peter J Houghton 《Cancer cell international》2009,9(1):16-21