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151.
We report a case of fatal disseminated infection with Cryptococcus gattii in a patient from New Mexico. The patient had no history of recent travel to known C. gattii-endemic areas. Multilocus sequence typing revealed that the isolate belonged to the major molecular type VGIII. Virulence studies in a mouse pulmonary model of infection demonstrated that the strain was less virulent than other C. gattii strains. This represents the first documented case of C. gattii likely acquired in New Mexico.  相似文献   
152.
We report here the new ‘creodont’ Lahimia selloumi gen. et sp. nov. from the late Palaeocene of the Ouled Abdoun Basin (Morocco) as the oldest known Hyaenodontidae with Tinerhodon from the Ouarzazate Basin (Morocco). By contrast to Tinerhodon, Lahimia is unexpectedly derived. Most of its specializations, such as the shortening of the anterior dentition (e.g. loss of P1) and the talonid reduction and simplification, are strikingly shared with Boualitomus from the Ypresian of the Ouled Abdoun Basin, and are distinctive from other hyaenodontids, including ‘proviverrines’. They are interpreted as synapomorphies evidencing a precociously specialized early African hyaenodontid lineage. Although Lahimia and Boualitomus remain known only by the lower dentition, their relationships with Koholia are suggested by comparison of their molar occlusal pattern. Lahimia and Boualitomus are referred to the Koholiinae, which is representative of an old African endemic lineage, as initially recognized. This remarkable lineage is characterized by synapomorphies of Lahimia and Boualitomus, and also by a shared original prevallum/postvallid shearing. The discovery of Lahimia provides direct evidence for the antiquity of the African evolution of the Hyaenodontidae. This is in agreement with an African origin of the Hyaenodontidae, and with the probable diphyletism of the ‘Creodonta’. Lahimia and the Koholiinae, as well as the diversity of the first Laurasian hyaenodontid lineages, emphasize our poor knowledge of the striking early African hyaenodontid radiation.  相似文献   
153.
Developmental plasticity may promote divergence by exposing genetic variation to selection in novel ways in new environments. We tested for this effect in the static allometry (i.e. scaling on body size) of traits in advertisement signals, body and genitalia. We used a member of the Enchenopa binotata species complex of treehoppers – a clade of plant‐feeding insects in which speciation is associated with colonization of novel environments involving marked divergence in signals, subtle divergence in body size and shape, and no apparent divergence in genitalia. We found no change in mean allometric slopes across environments, but substantial genetic variation and genotype × environment interaction (G × E) in allometry. The allometry of signal traits showed the most genetic variation and G × E, and that of genitalia showed the weakest G × E. Our findings suggest that colonizing novel environments may have stronger diversifying consequences for signal allometry than for genitalia allometry. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 187–196.  相似文献   
154.
In the present study, bee colonies were smoked with tobacco smoke in order to evaluate the monthly changes in the numbers of worker bees, the infestation rates of worker bees and queens with bee lice, and the annual average honey production per colony. In July of each year, 12 colonies were smoked with tobacco smoke; the remaining hives not smoked with tobacco smoke served as the control. The results indicated that the applications of tobacco smoke during July gave rise to an impressive reduction in the Braula infestation rate on workers (below 1.8%) and reduced the amount of bee lice on the queen to zero throughout the 2–3 months following smoke treatment. In the colonies not treated with smoke, the Braula infestation rates on worker bees started to increase in May and continued to increase constantly during the rest of year, reaching maximum infestation rates of 28.2% and 33.8% in December, with an average of 15 and 17 lice per queen in November in the first and second years, respectively. Worker bee populations peaked in April and July of each year in both treatments. The average honey production per colony was significantly higher in the colonies treated with smoke than those that were not for the first and second years. In conclusion, early summer months may be the crucial time to smoke the colonies with tobacco smoke in order to keep bee lice at low levels for the remaining seasons.  相似文献   
155.

Background  

In contemporary biology, complex biological processes are increasingly studied by collecting and analyzing measurements of the same entities that are collected with different analytical platforms. Such data comprise a number of data blocks that are coupled via a common mode. The goal of collecting this type of data is to discover biological mechanisms that underlie the behavior of the variables in the different data blocks. The simultaneous component analysis (SCA) family of data analysis methods is suited for this task. However, a SCA may be hampered by the data blocks being subjected to different amounts of measurement error, or noise. To unveil the true mechanisms underlying the data, it could be fruitful to take noise heterogeneity into consideration in the data analysis. Maximum likelihood based SCA (MxLSCA-P) was developed for this purpose. In a previous simulation study it outperformed normal SCA-P. This previous study, however, did not mimic in many respects typical functional genomics data sets, such as, data blocks coupled via the experimental mode, more variables than experimental units, and medium to high correlations between variables. Here, we present a new simulation study in which the usefulness of MxLSCA-P compared to ordinary SCA-P is evaluated within a typical functional genomics setting. Subsequently, the performance of the two methods is evaluated by analysis of a real life Escherichia coli metabolomics data set.  相似文献   
156.
157.

Background

HTLV-I infection has been linked to lung pathology and HTLV-II has been associated with an increased incidence of pneumonia and acute bronchitis. However it is unknown whether HTLV-I or -II infection alters pulmonary function.

Methods

We performed pulmonary function testing on HTLV-I, HTLV-II and HTLV seronegative subjects from the HTLV outcomes study (HOST), including vital capacity (VC), forced expiratory volume in one second (FEV1), and diffusing lung capacity for carbon monoxide (DLCO) corrected for hemoglobin and lung volume. Multivariable analysis adjusted for differences in age, gender, race/ethnicity, height and smoking history.

Results

Mean (standard deviation) pulmonary function values among the 257 subjects were as follows: FVC = 3.74 (0.89) L, FEV1 = 2.93 (0.67) L, DLCOcorr = 23.82 (5.89) ml/min/mmHg, alveolar ventilation (VA) = 5.25 (1.20) L and DLCOcorr/VA = 4.54 (0.87) ml/min/mmHg/L. There were no differences in FVC, FEV1 and DLCOcorr/VA by HTLV status. For DLCOcorr, HTLV-I and HTLV-II subjects had slightly lower values than seronegatives, but neither difference was statistically significant after adjustment for confounding.

Conclusions

There was no difference in measured pulmonary function and diffusing capacity in generally healthy HTLV-I and HTLV-II subjects compared to seronegatives. These results suggest that previously described HTLV-associated abnormalities in bronchoalveolar cells and fluid may not affect pulmonary function.  相似文献   
158.
Molete JM  Petrykowska H  Sigg M  Miller W  Hardison R 《Gene》2002,283(1-2):185-197
The distal locus control region (LCR) is required for high-level expression of the complex of genes (HBBC) encoding the beta-like globins of mammals in erythroid cells. Several major DNase hypersensitive sites (HSs 1-5) mark the LCR. Sequence conservation and direct experimental evidence have implicated sequences within and between the HS cores in function of the LCR. In this report we confirm the mapping of a minor HS between HS3 and HS4, called HS3.2, and show that sequences including it increase the number of random integration sites at which a drug resistance gene is expressed. We also show that nuclear proteins including GATA1 and Oct1 bind specifically to sequences within HS3.2. However, the protein Pbx1, whose binding site is the best match to one highly conserved sequence, does not bind strongly. GATA1 and Oct1 also bind in the HS cores of the LCR and to promoters in HBBC. Their binding to this minor HS suggests that they may be used in assembly of a large complex containing multiple regulatory sequences.  相似文献   
159.
We have identified the first gene lying on the centromeric side of the alpha-globin gene cluster on human 16p13.3. The gene, called 16pHQG;16 (HGMW-approved symbol LUC7L), is widely transcribed and lies in the opposite orientation with respect to the alpha-globin genes. This gene may represent a mammalian heterochromatic gene, encoding a putative RNA-binding protein similar to the yeast Luc7p subunit of the U1 snRNP splicing complex that is normally required for 5' splice site selection. To examine the role of the 16pHQG;16 gene in delimiting the extent of the alpha-globin regulatory domain, we mapped its mouse orthologue, which we found to lie on mouse chromosome 17, separated from the mouse alpha-cluster on chromosome 11. Establishing the full extent of the human 16pHQG;16 gene has allowed us to define the centromeric limit of the region of conserved synteny around the human alpha-globin cluster to within an 8-kb segment of chromosome 16.  相似文献   
160.
Intracerebral infection of mice with mouse hepatitis virus, a member of the Coronaviridae family, reproducibly results in an acute encephalomyelitis that progresses to a chronic demyelinating disease. The ensuing neuropathology during the chronic stage of disease is primarily immune mediated and similar to that of the human demyelinating disease multiple sclerosis. Secretion of chemokines within the CNS signals the infiltration of leukocytes, which results in destruction of white matter and neurological impairment. The CC chemokine ligand (CCL)5 is localized in white matter tracts undergoing demyelination, suggesting that this chemokine participates in the pathogenesis of disease by attracting inflammatory cells into the CNS. In this study, we administer a mAb directed against CCL5 to mice with established mouse hepatitis virus-induced demyelination and impaired motor skills. Anti-CCL5 treatment decreased T cell accumulation within the CNS based, in part, on viral Ag specificity, indicating the ability to differentially target select populations of T cells. In addition, administration of anti-CCL5 improved neurological function and significantly (p < or = 0.005) reduced the severity of demyelination and macrophage accumulation within the CNS. These results demonstrate that the severity of CNS disease can be reduced through the use of a neutralizing mAb directed against CCL5 in a viral model of demyelination.  相似文献   
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