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Background:Infectious bronchitis virus (IBV) causes severe economic losses worldwide. IBV has a broad tissue distribution with different viral loads in different tissues. Additionally, IBV can induce apoptosis in infected cells. Aims:The present study aimed to evaluate the role of the genetic background of chickens in viral load and the expression level of apoptotic genes in different tissues of two hybrids of commercial broiler chickens (Ross 308 and Cobb 500) challenged with IBV. Methods:Chickens at 21 days of age were nasally challenged with 200 μL of allantoic fluid containing 104 EID50/ml of Iranian variant-2-like IBV (IS/1494). The expression level of apoptotic genes (Fas, FasL, Bax, and Bcl-2) in the tracheal and renal tissues and the amount of viral load in the tracheal, renal, and cloacal swab samples were investigated two, five, and seven days after IBV infection by RT-qPCR assay. Results:The amount of viral load and apoptotic the expression level of apoptotic genes in the tracheal (two and five days after infection) and renal samples (seven days after infection) were significantly higher in the Ross challenged group than in the Cobb challenged group.Furthermore, no difference was observed in the cloaca viral load on sampling days. Conclusion:To our knowledge, this is the first report that evaluated the role of the chickens’ genetic background in the amount of viral load and the expression level of apoptotic genes against IBV. Further studies are needed to investigate the pathogenic characteristics of IBV in Ross 308 and Cobb 500 chickens.Key Words: Apoptosis, Broiler chickens, Infectious bronchitis virus, Viral load  相似文献   
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BackgroundPregnancy is a major concern among women with the sickle cell disease (SCD), and it is associated with increased adverse outcomes. The aim of the present meta-analysis is to report the fetomaternal outcomes in different sickle cell genotypes.MethodsIn this systematic review and meta-analysis, a comprehensive search of databases and search engines such as PubMed, Scopus, Web of Science, ProQuest, Cochrane Library, Science Direct and Google Scholar were performed. Any observational studies that had compared at least one outcome such as maternal outcomes, fetal outcomes, and morbidity between two groups of pregnant women with different types of sickle cell genotypes and pregnant women without SCD were evaluated.ResultsA total number of 9,827 pregnant women with SCD were examined. The results showed that pregnancy in SCD increased the risk of adverse outcomes for the mothers (including postpartum hemorrhage, prematurity, pregnancy-induced hypertension, pre-eclampsia, eclampsia, cesarean section, lower segment cesareansection, maternal death), fetus (including live births, low birth weight, intrauterine growth restriction, APGAR score at 5 min <7, stillbirth, neonatal death, perinatal mortality, acute fetal distress, intrauterine fetal death) and morbidity among the SCD(severe anemia, urinary tract infection, blood transfusion, painful crisis, acute chest syndrome, vaso-occlusive crises).ConclusionAccording to the results of this meta-analysis, pregnancy in the SCD is associated with an increased risk of maternal outcomes, fetal outcomes, and morbidity among SCD patients with different genotypes. Pregnancy in sickle cell hemoglobinopathies needs careful multidisciplinary management and cautious caring so as to decrease maternal and fetal morbidity and mortality.  相似文献   
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Phytoestrogens with a biological activity like estradiol are naturally found in many plants. This study was designed to investigate the effect of red clover, a phytoestrogen-rich member of the legume family (Trifolium pratense) on the development of atherosclerosis in male hyperlipidemic rabbits. Twenty rabbits were semi-randomly distributed into four groups of five each. Two groups received either normal diet or normal diet supplemented with red clover. Two other groups received similar diets to both of which 1% cholesterol was added. Dietary use of red clover (RC) in hyperlipidemic rabbits significantly decreased C-reactive protein (CRP), triglyceride (TG), total cholesterol and LDL-cholesterol (LDL-C) whereas, HDL-cholesterol (HDL-C) was significantly increased in those animals (p < 0.05). Fatty streak formation was also significantly lower in aorta and left and right coronary arteries in the same animals due to use of dietary RC supplementation. These findings suggest that dietary RC may reduce cardiovascular risk factors.  相似文献   
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Alzheimer's disease (AD) is characterized by neuronal atrophy caused by soluble amyloid beta protein (Abeta) peptide "oligomers" and a microglial-mediated inflammatory response elicited by extensive amyloid deposition in the brain. We show that CNI-1493, a tetravalent guanylhydrazone with established antiinflammatory properties, interferes with Abeta assembly and protects neuronal cells from the toxic effect of soluble Abeta oligomers. Administration of CNI-1493 to TgCRND8 mice overexpressing human amyloid precursor protein (APP) for a treatment period of 8 wk significantly reduced Abeta deposition. CNI-1493 treatment resulted in 70% reduction of amyloid plaque area in the cortex and 87% reduction in the hippocampus of these animals. Administration of CNI-1493 significantly improved memory performance in a cognition task compared with vehicle-treated mice. In vitro analysis of CNI-1493 on APP processing in an APP-overexpressing cell line revealed a significant dose-dependent decrease of total Abeta accumulation. This study indicates that the antiinflammatory agent CNI-1493 can ameliorate the pathophysiology and cognitive defects in a murine model of AD.  相似文献   
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4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitro-4H-benzo[g]chromene-5,10-dione) and 4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitropyrano[3,2-c]chromen-5(4H)-one) derivatives are synthesized by a one-pot, multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine (derived from the reaction of various amines and 1,1-bis(methylthio)-2-nitroethene) with terephthalaldehyde or isophthalaldehyde, and 2-hydroxy-1,4-naphthoquinone or 4-hydroxycoumarin in EtOH/H2O (85 : 15) as the solvent at 89 °C. Response surface methodology (RSM) is used to investigate the effect of reaction temperature and water content of aqueous ethanol on the product yields and reaction time. The notable features of this work are the optimization of reaction conditions with minimal experiments, absence of catalyst, good yields, simple work-up and the non-chromatographic purification of products.

One-pot synthesis of C2-symmetric chromene derivatives, which serve as building blocks to prepare liquid crystals with potential electrical or optical properties.  相似文献   
18.
Behçet’s disease (BD) is a chronic autoimmune condition primarily prevalent in populations along the Mediterranean Sea. The exact etiology of BD has not been fully explained yet, but the disease occurrence is associated with a genetic factor, human leukocyte antigen (HLA)-B51 antigen. Among the various immunodysfunctions that are found in BD, patients are increased neutrophil motility and superoxide production, as well as elevated production of tumor necrosis factor (TNF)-α and decreased production of interleukin (IL)-10. Elevated levels of inflammatory cytokines like IL-1 and IL-17 in BD have been found associated with aberrant expression of microRNA. Gene polymorphisms in BD patients have been observed in molecules involved in responses to pathogens that can ultimately modulate the host antimicrobial response. Moreover, several single nucleotide polymorphisms (SNPs) have been reported in genes encoding chemokines and adhesion molecules; many of these changes manifest as increases in vascular inflammation and vascular damage. Lastly, genetic and epigenetic changes have been suggested as involved in the pathogenesis of BD. Modifications in DNA methylation have been found in BD patient monocytes and lymphocytes, leading to adverse function of these cells. This review presents a comprehensive compilation of the literature with regard to the immunodysfunction underlying BD, as well as of the genetics, newly described clinical specifications and novel treatment strategies using immunomodulants based on the current understanding of BD.  相似文献   
19.
Numerous studies demonstrate that neuroinflammation is a key player in the progression of Alzheimer’s disease (AD). Interleukin (IL)-1β is a main inducer of inflammation and therefore a prime target for therapeutic options. The inactive IL-1β precursor requires processing by the the nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome into a mature and active form. Studies have shown that IL-1β is up-regulated in brains of patients with AD, and that genetic inactivation of the NLRP3 inflammasome improves behavioral tests and synaptic plasticity phenotypes in a murine model of the disease. In the present study, we analyzed the effect of pharmacological inhibition of the NLRP3 inflammasome using dapansutrile (OLT1177), an oral NLRP3-specific inhibitor that is safe in humans. Six-month-old WT and APP/PS1 mice were fed with standard mouse chow or OLT1177-enriched chow for 3 mo. The Morris water maze test revealed an impaired learning and memory ability of 9-mo-old APP/PS1 mice (P = 0.001), which was completely rescued by OLT1177 fed to mice (P = 0.008 to untreated APP/PS1). Furthermore, our findings revealed that 3 mo of OLT1177 diet can rescue synaptic plasticity in this mouse model of AD (P = 0.007 to untreated APP/PS1). In addition, microglia were less activated (P = 0.07) and the number of plaques was reduced in the cortex (P = 0.03) following NLRP3 inhibition with OLT1177 administration. We also observed an OLT1177 dose-dependent normalization of plasma metabolic markers of AD to those of WT mice. This study suggests the therapeutic potential of treating neuroinflammation with an oral inhibitor of the NLRP3 inflammasome.

Alzheimer’s disease (AD) and other related neurodegenerative diseases leading to dementia represent an enormous burden for the society and health economies. AD patients suffer progressive cognitive and functional deficits often for many years, which result in a heavy burden to patients, families, and the public health system. In fact, in 2015 an estimated 46.8 million people worldwide were living with dementia, which could extend to 131.5 million by 2050 (1). Rising prevalence and mortality rates in combination with a lack of effective treatments lead to enormous costs to society. Research on AD in the last decades has focused on the pathological hallmarks and cellular deposits of amyloid-β (Aβ) peptides and neurofibrils (2). Recently, there has been increased evidence supporting a central role of the immune system in the progression or even the origin of the disease (35). In this respect, it is noteworthy that it has been known since 1989 that levels of interleukin (IL)-1β, one of the main mediators of innate immune response, are elevated in brains of patients with AD and can be associated with the progression and onset of AD (611). Additionally, it was shown that the nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome (12, 13), a multisubunit complex important for the maturation of IL-1β, is activated by Aβ peptides, leading to an overproduction of IL-1β, neuroinflammation, and cognitive impairment (14, 15). Inhibition of the NLRP3 inflammasome and the subsequent reduced IL-1β production can be linked to a change in the phenotype of microglia, the innate immune cells in the brain. Heneka et al. (16) pointed out the important role of the NLRP3 inflammasome/caspase-1 axis in AD pathogenesis by demonstrating significant improvements (e.g., in cognition) in APP/PS1 mice (a mouse model for AD) when crossed with NLRP3−/− animals. The APP/PS1 mice express a human amyloid precursor protein (APP) and human presenilin-1 (PS1), leading to the accumulation of Aβ peptides, neuroinflammation, and cognitive impairment (17).OLT1177 (rINN: dapansutrile) is a new chemical entity small molecule that specifically targets the NLRP3 inflammasome and prevents the activation of caspase-1 and the maturation and release of IL-1β (18). OLT1177 has been shown to be well tolerated in animals and humans (18) and is currently in phase 2 clinical studies for the treatment of inflammatory conditions, such as osteoarthritis (topical gel dosage form) and inflammatory diseases, such as acute gout flare (oral capsule dosage form), among other diseases (19).In this study, we used the APP/PS1 mouse model of AD to investigate the effects of OLT1177 as an acute, oral pharmacological intervention (17). Six-month-old WT and APP/PS1ΔE9 mice consumed ad libitum OLT1177 in feed pellets (∼0, 500, or 1,000 mg/kg/d based on feed concentrations of 0, 3.75 or 7.5 g of OLT1177 per kilogram of feed; hereafter referred to as 3.75 or 7.5 g/kg OLT1177) for the treatment duration of 3 mo. APP/PS1 mice treated with OLT1177 showed rescue effects in various assessments, ranging from improved cognitive function to overall reduction in proinflammatory cytokines in the brain, suggesting the potential benefits of pharmaceutically blocking NLRP3 signaling in AD.  相似文献   
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We investigated whether the severity of septic shock is determined by virulence factors associated with or the levels of endotoxemia produced by two Escherichia coli strains. Canines were challenged intraperitoneally with an E. coli strain (O6:H1:K2) that has virulence factors associated with human disease or with an equal dose of a nonvirulent strain (O86:H8) that lacks these factors. Both strains were administered in viable, heat-killed, and purified endotoxin forms. Median survival times with the virulent strain compared with the nonvirulent strain were shorter with viable bacteria (5 x 10(10) CFU/kg) (144 h versus > 672 h; Wilcoxon, P = 0.03), longer with heat-killed bacteria (5 x 10(9) CFU/kg) ( > 676 h versus 26 h; P = 0.03), and similar with purified endotoxin (15 mg/kg) (28 h versus 48 h; P = 0.71). However, whether the challenge contained viable bacteria, heat-killed bacteria, or purified endotoxin, the virulent strain produced less endotoxemia (P = 0.001). Hence, the changing outcomes with differing forms of the two strains cannot be attributed solely to endotoxin levels. The viable virulent strain caused less endotoxemia but more harm, and this does not appear to be explained by a more potent endotoxin or other heat-stable component. This study suggests that circulating endotoxin levels per se are less important in the outcome of septic shock than virulence factors associated with E. coli strains. Furthermore, the data call into question the significance of the endotoxin concentration in the blood in predicting the severity of shock and the lethality of gram-negative infections.  相似文献   
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