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161.
The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa) comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10-1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species are known from the bathyal and abyssal Antarctic than Arctic GOODS provinces, and more from the larger Pacific than Atlantic oceans. Two areas with many species known are the New Zealand-Kermadec and the Northern North Pacific provinces. Deep hard substrates such as found on seamounts and the slopes are underrepresented in samples. This, the documented numbers of undescribed species in recent collections and probable cryptic species suggest a large as yet undocumented fauna, potentially an order of magnitude greater than presently known. 相似文献
162.
ABSTRACT: Sexual differentiation of the nervous system occurs via the interplay of genetics, endocrinology and social experience through development. Much of the research into mechanisms of sexual differentiation has been driven by an implicit theoretical framework in which these causal factors act primarily and directly on sexually dimorphic neural populations within the central nervous system. This review will examine an alternative explanation by describing what is known about the role of peripheral structures and mechanisms (both neural and non-neural) in producing sex differences in the central nervous system. The focus of the review will be on experimental evidence obtained from studies of androgenic masculinization of the spinal nucleus of the bulbocavernosus, but other systems will also be considered. 相似文献
163.
B Ogunjimi D Peeters N Hens R Malfait V Van Tendeloo P Van Damme P Beutels E Smits 《PloS one》2012,7(7):e41405
Clinical and scientific work routinely relies on antecubital venipunctures for hematological, immunological or other analyses on blood. This study tested the hypothesis that antecubital veins can be considered to be a good proxy for other sampling sites. Using a hematocytometer and a flow cytometer, we analyzed the cell counts from samples coming from the radial artery, the dorsal hand veins and the antecubital veins from 18 volunteers. Most surprisingly, we identified the greatest difference not to exist between arterial and venous circulation, but between the distal (radial artery & dorsal hand veins) and proximal (antecubital veins) sampling sites. Naïve T cells had a higher cell count distally compared to proximally and the reverse was true for effector memory T cells. Despite these differences there were high correlations between the different sampling sites, which partially supports our initial hypothesis. Our findings are crucial for the future design and interpretation of immunological research, and for clinical practice. Furthermore, our results suggest a role for interval lymph nodes in the trafficking of lymphocytes. 相似文献
164.
A Massaú C Martins GC Nachtigal AB Araújo ML Rossetti C Niel CM Silva 《Memórias do Instituto Oswaldo Cruz》2012,107(5):684-686
This study investigates the frequency of Torque teno virus (TTV) infection in 150 blood donors and 77 patients requiring haemodialysis in southern Brazil. Plasma samples were screened for TTV DNA using polymerase chain reaction (PCR). The prevalences of TTV among blood donors and patients requiring haemodialysis were 73.3% and 68.8%, respectively. The presence of TTV was correlated with age in the blood donors (p = 0.024). In haemodialysis patients, no association was found between TTV infection and the demographic parameters (age, sex and education), the duration of haemodialysis or a history of blood transfusion. This study is the first to evaluate the prevalence of TTV infection in Brazilian patients requiring haemodialysis. 相似文献
165.
The aim of this study was to identify the presence of SNPs in the chemokine genes CCL2 and IL8 and the chemokine receptor genes IL8RA and CCR2, and assess their potential contribution to variation in estimated breeding values (EBVs) for somatic cell score (SCS) and four other traits in Canadian Holstein bulls. Pools of DNA for bulls with high (H) and low (L) EBVs for SCS were used for identification of 11 SNPs. Two unreported SNPs were found in the CCL2 gene and one SNP was found in the CCR2 gene. Previously reported SNPs (three in the IL8 gene and five in the IL8RA chemokine receptor) were also identified. Two SNPs in CCL2, three in IL8, one in IL8RA and one in CCR2 were genotyped in Canadian Holstein bulls (n = 338) using tetra primer ARMS-PCR. We investigated associations of these seven polymorphisms with three production traits (milk yield, fat yield and protein yield) and one conformation trait related to mastitis (udder depth). The allele substitution effect for the CCL2 rs41255713:T>C SNP was significant at an experimental-wise level for milk yield (247.5 +/- 79.9 kg) and protein yield (7.4 +/- 2.3 kg) EBVs (P T SNP on SCS was significant at the comparison-wise level (-0.04 +/- 0.02, P = 0.05), which might indicate a possible association in support of other published studies. Lastly, we assigned CCR2 to BTA22q24, where a previously QTL for SCS was identified. 相似文献
166.
Mycobacterium avium ssp. paratuberculosis (MAP) infection in cattle causes significant economic losses to the dairy and beef industries resulting from reduced productivity, premature culling and mortality. Bovine Dectin-1, an important pattern recognition molecule that is able to generate a proinflammatory response by acting alongside Toll like receptor (TLR) signaling, is known to co-operate with TLR2 to specifically activate a macrophage proinflammatory response against mycobacterial infections. Therefore, the goal of this study was to identify single nucleotide polymorphisms (SNPs) in the gene encoding bovine Dectin-1 (CLEC7A) and to assess their association with susceptibility to MAP infection in dairy cattle. Blood and milk samples, collected from commercial dairy operations, were tested for MAP infection using blood and milk ELISAs and a resource population consisting of 197 infected and 242 healthy cattle was constructed. Pooled DNA was used for sequencing and eight single nucleotide polymorphisms (SNPs) were identified. Identified SNPs were genotyped on the resource population using the iPLEX MassARRAY system and statistical analysis was performed using logistic regression fitting the additive and dominance effects of each SNP in the model. Out of a total of eight identified SNPs, five were successfully genotyped, and three out of these five SNPs were found to be in complete linkage. Statistical analysis revealed a strong association between a non-synonymous SNP c.589A>G (p = 0.008), and MAP infection status of the resource population inferred by seropositivity in MAP antibody specific ELISAs. This SNP c.589A>G was located in the geneic region that encodes the carbohydrate recognition domain of bovine Dectin-1. Therefore, further investigation of its functional relevance is warranted. 相似文献
167.
Tarciana Grandi Cláudia Maria Dornelles da Silva Karine Medeiros Amaral Paulo Dornelles Picon Cintia Costi Nicole Nascimento da Fré Marilu Fiegenbaum Tatiana Sch?ffer Gregianini Christian Niel Maria Lucia Rosa Rossetti 《Memórias do Instituto Oswaldo Cruz》2014,109(3):345-351
Certain host single nucleotide polymorphisms (SNPs) affect the likelihood of a
sustained virological response (SVR) to treatment in subjects infected with hepatitis
C virus (HCV). SNPs in the promoters of interleukin (IL)-10 (-1082 A/G, rs1800896),
myxovirus resistance protein 1 (-123 C/A, rs17000900 and -88 G/T, rs2071430) and
tumour necrosis factor (TNF) (-308 G/A, rs1800629 and -238 G/A, rs361525) genes and
the outcome of PEGylated α-interferon plus ribavirin therapy were investigated. This
analysis was performed in 114 Brazilian, HCV genotype 1-infected patients who had a
SVR and in 85 non-responders and 64 relapsers. A significantly increased risk of
having a null virological response was observed in patients carrying at least one A
allele at positions -308 [odds ratios (OR) = 2.58, 95% confidence intervals (CI) =
1.44-4.63, p = 0.001] or -238 (OR = 7.33, 95% CI = 3.59-14.93, p < 0.001) in the
TNF promoter. The risk of relapsing was also elevated (-308: OR = 2.87, 95% CI =
1.51-5.44, p = 0.001; -238: OR = 4.20, 95% CI = 1.93-9.10, p < 0.001). Multiple
logistic regression of TNF diplotypes showed that patients with at least two copies
of the A allele had an even higher risk of having a null virological response (OR =
16.43, 95% CI = 5.70-47.34, p < 0.001) or relapsing (OR = 6.71, 95% CI =
2.18-20.66, p = 0.001). No statistically significant association was found between
the other SNPs under study and anti-HCV therapy response. 相似文献
168.
169.
Sphingolipids are present in all eukaryotic cells and share a sphingoid base : sphingosine. They were first discovered in 1884 and for a long time they were thought to participate to membrane structure only. Recently it has been established that they are mainly located in particular areas of the membrane called rafts which are signalling platforms. It has also been demonstrated that sphingolipids are receptors and second messengers. They play a crucial role in cellular functioning and are necessary to maintenance and developing of living organisms. However due to their receptor properties, they are also gateway for penetration of pathogenic agents such as virus (Ebola, HIV) or toxins (botulinium, tetanus). These agents first bind to glycosphingolipids or proteins mainly located in rafts. The complex so formed is required for the crossing of the membrane by the pathogenic agent. Sphingolipids metabolism is regulated by numerous enzymes. A failure in the activity of one of them induces an accumulation of sphingolipids known as sphingolipidoses. These are genetic diseases having severe consequences for the survival of the organism. The precise mechanisms of the sphingolipidoses are still mainly unknown which explains why few therapeutic strategies are available. These particular properties of lipids rafts and sphingolipids explain why a growing number of studies in the medical and scientific fields are devoted to them. 相似文献
170.
Bakytbek Egemnazarov Ralph T Schermuly Bhola K Dahal Garry T Elliott Niel C Hoglen Mark W Surber Norbert Weissmann Friedrich Grimminger Werner Seeger Hossein A Ghofrani 《Respiratory research》2010,11(1):81