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81.
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83.
Toshihiro Yoshida So Kawaguchi Bettina Meyer Patti Virtue Jennifer Penschow Gerry Nash 《Polar Biology》2009,32(3):503-507
The effects of starvation on ultrastructure of digestive gland cells were studied in furcilia larvae of Antarctic krill (Euphausia superba: hereafter krill). Under laboratory conditions, larvae were starved for 0, 5, 10, 15, 20 and 25 days, and their R-cells were
investigated by transmission electron microscope. R-cells are thought to play a role in the storage and absorption of nutrients.
In fed larvae, numerous mitochondria scattered homogenously, and densely packed microvilli were observed on the apical surface
of R-cells. After 5 days of starvation, mitochondria were swollen and were found concentrated in the apical region in R-cells.
A decrease in cell volume and an increase in thickness of the basal lamina with many irregular infoldings were observed after
10–15 days of starvation. Lipid droplets were rarely found in the R-cells regardless of whether larvae had been fed or starved
suggesting an inability to store lipid. Without the ability to store energy in the form of lipid, survival would be dependant
on sourcing continuous food until maturation. 相似文献
84.
85.
Francesco Oliva Loredana Zocchi Eleonora Candi Gerry Melino Umberto Tarantino 《Biochemical and biophysical research communications》2009,379(4):887-891
The ethiopathogenesis of rotator cuff disease remains poorly understood. Many studies advocate the importance of extra cellular matrix for the homeostasis of connective tissue. Transglutaminase enzymes family has been studied in the context of connective tissue formation and stabilisation. Here, we investigated transglutaminases expression pattern in biopsies of normal and injured supraspinatus tendons of human shoulders and in the Achilles tendons of transglutaminase 2 knock-out and wild-type mice. Our results show that different transglutaminase family members are differentially expressed in human and mouse tendons, and that transglutaminase 2 is down-regulated at mRNA and protein levels upon human supraspinatus tendon ruptures. 相似文献
86.
Adebowale Adeyemo Norman Gerry Guanjie Chen Alan Herbert Ayo Doumatey Hanxia Huang Jie Zhou Kerrie Lashley Yuanxiu Chen Michael Christman Charles Rotimi 《PLoS genetics》2009,5(7)
The evidence for the existence of genetic susceptibility variants for the common form of hypertension (“essential hypertension”) remains weak and inconsistent. We sought genetic variants underlying blood pressure (BP) by conducting a genome-wide association study (GWAS) among African Americans, a population group in the United States that is disproportionately affected by hypertension and associated complications, including stroke and kidney diseases. Using a dense panel of over 800,000 SNPs in a discovery sample of 1,017 African Americans from the Washington, D.C., metropolitan region, we identified multiple SNPs reaching genome-wide significance for systolic BP in or near the genes: PMS1, SLC24A4, YWHA7, IPO7, and CACANA1H. Two of these genes, SLC24A4 (a sodium/potassium/calcium exchanger) and CACNA1H (a voltage-dependent calcium channel), are potential candidate genes for BP regulation and the latter is a drug target for a class of calcium channel blockers. No variant reached genome wide significance for association with diastolic BP (top scoring SNP rs1867226, p = 5.8×10−7) or with hypertension as a binary trait (top scoring SNP rs9791170, p = 5.1×10−7). We replicated some of the significant SNPs in a sample of West Africans. Pathway analysis revealed that genes harboring top-scoring variants cluster in pathways and networks of biologic relevance to hypertension and BP regulation. This is the first GWAS for hypertension and BP in an African American population. The findings suggests that, in addition to or in lieu of relying solely on replicated variants of moderate-to-large effect reaching genome-wide significance, pathway and network approaches may be useful in identifying and prioritizing candidate genes/loci for further experiments. 相似文献
87.
Randolph R. J. Arroo Vasilis Androutsopoulos Kenneth Beresford Ketan Ruparelia Somchaiya Surichan Nicola Wilsher Gerry A. Potter 《Phytochemistry Reviews》2009,8(2):375-386
There are many reasons why vegetables and fruits may protect against cancer. As well as containing vitamins and minerals,
which help keep the body healthy and strengthen the immune system, they are also good sources of biologically active compounds,
which can help to protect cells in the body from damage that can lead to cancer. Notably, dietary flavonoids and other polyphenols
are thought to have an important role as chemopreventive agents. Most studies on the possible mechanism of the chemopreventive
action of dietary compounds have assumed that free hydroxyl groups of flavonoids and other polyphenols are necessary for their
biological effects. However, in the human body dietary polyphenols are rapidly conjugated by glucuronosyltransferases and
sulfotransferases, two enzymes that are abundantly present in the small intestine and liver, through which all of the oral
dose must pass. Thus, most polyphenols that have been studied, e.g. quercetin, kaempferol, diosmetin, and resveratrol, would
not be expected to reach internal organs beyond sites directly along the gastrointestinal tract. When the hydroxyl groups
in polyphenols are methylated, the resulting compounds are much less prone to glucuronidation and sulfation. Thus methoxylated
compounds are more metabolically stable, increasing their bioavailablity. The peel of various Citrus species can contain high
concentrations of polymethoxyflavones, whereas the juice mainly contains hydroxylated flavones. At present, very little is
known about the mechanisms by which methoxylated flavones may affect growth and development of tumour cells. Recently, it
was shown that tumour specific enzymes can catalyze the O-demethylation of methoxylated flavones, resulting in the formation of flavones with free hydroxyl groups. We propose that
demethylation of methoxylated flavones is another example of bioactivation of naturally occurring prodrugs. 相似文献
88.
Sheila B. Ogoma Dickson W. Lweitoijera Hassan Ngonyani Benjamin Furer Tanya L. Russell Wolfgang R. Mukabana Gerry F. Killeen Sarah J. Moore 《PLoS neglected tropical diseases》2010,4(8)
Background
Partial mosquito-proofing of houses with screens and ceilings has the potential to reduce indoor densities of malaria mosquitoes. We wish to measure whether it will also reduce indoor densities of vectors of neglected tropical diseases.Methodology
The main house entry points preferred by anopheline and culicine vectors were determined through controlled experiments using specially designed experimental huts and village houses in Lupiro village, southern Tanzania. The benefit of screening different entry points (eaves, windows and doors) using PVC-coated fibre glass netting material in terms of reduced indoor densities of mosquitoes was evaluated compared to the control.Findings
23,027 mosquitoes were caught with CDC light traps; 77.9% (17,929) were Anopheles gambiae sensu lato, of which 66.2% were An. arabiensis and 33.8% An. gambiae sensu stricto. The remainder comprised 0.2% (50) An. funestus, 10.2% (2359) Culex spp. and 11.6% (2664) Mansonia spp. Screening eaves reduced densities of Anopheles gambiae s. l. (Relative ratio (RR) = 0.91; 95% CI = 0.84, 0.98; P = 0.01); Mansonia africana (RR = 0.43; 95% CI = 0.26, 0.76; P<0.001) and Mansonia uniformis (RR = 0.37; 95% CI = 0.25, 0.56; P<0.001) but not Culex quinquefasciatus, Cx. univittatus or Cx. theileri. Numbers of these species were reduced by screening windows and doors but this was not significant.Significance
This study confirms that across Africa, screening eaves protects households against important mosquito vectors of filariasis, Rift Valley Fever and O''Nyong nyong as well as malaria. While full house screening is required to exclude Culex species mosquitoes, screening of eaves alone or fitting ceilings has considerable potential for integrated control of other vectors of filariasis, arbovirus and malaria. 相似文献89.
Alessandro Mauriello Manuel Scimeca Ivano Amelio Renato Massoud Antonio Novelli Francesca Di Lorenzo Susanna Finocchiaro Carolina Cimino Rossana Telesca Marcello Chiocchi Qiang Sun Ying Wang Yufang Shi Giuseppe Novelli Gerry Melino 《Cell death & disease》2021,12(8)
While vaccination is the single most effective intervention to drastically reduce severe disease and death following SARS-CoV-2 infection, as shown in UK and Israel, some serious concerns have been raised for an unusual adverse drug reaction (ADR), including vaccine-induced immune thrombotic thrombocytopenia (VITT) with concurrent low platelets as well as capillary leak syndrome. In fact, the overall safety of the vaccine is highlighted by the low frequency of ADR considering that in UK, by the early June, 40 million first doses and 29 million second doses have been injected; nonetheless, 390 thrombotic events, including 71 fatal events have been reported. Interestingly, the cases reported low platelet counts with the presence of anti-platelet factor-4 (PF4) antibodies, indicating an abnormal clotting reaction. Here, out of three referred cases, we report a post-vaccine clinical case of fatal thrombosis with postmortem examination and whole exome sequencing (WES) analysis, whose pathogenesis appeared associated to a preexisting condition of thrombocytopenia due to myelodysplasia.Subject terms: Diseases, Medical research 相似文献
90.
Apoptosis, a genetically regulated form of cell death with distinct biochemical and morphological features, plays a relevant physiological and pathological role in the organism, being pivotal in the maintenance of tissue development and homeostasis in the adult as well as in the regulation of immune responses. Deregulation of this process causes several human disorders including cancer, autoimmune and neurodegenerative diseases. Thus, modulation of the apoptotic process and of cell death in general, is a potential therapeutic approach for the treatment of several human pathologies. 相似文献