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41.
Mutations in the myocilin gene (MYOC) account for most cases of autosomal dominant juvenile-onset open-angle glaucoma (JOAG), an earlier and more severe form of POAG. We accessed seven members of a Brazilian JOAG family by clinical and molecular investigation. Four out of seven family members were diagnosed with JOAG. All of these patients presented high intraocular pressure and two of them were bilaterally blind. The disease onset varied from 20 to 30 years old. There was a nine-year-old family member who had not yet manifested the disease, although he was also a carrier of the mutation. Ophthalmologic examination included: evaluation of the visual field and optic disc, intraocular pressure measurement, and gonioscopy. The three exons and intron/exon junctions of the MYOC gene were screened for mutations through direct sequencing of PCR-amplified DNA fragments. Mutation screening revealed an in-frame mutation in the third exon of the MYOC gene: an insertion of six nucleotides between the cDNA positions 1187 and 1188 (c.1187_1188insCCCAGA, p.D395_E396insDP). This mutation presented an autosomal dominant pattern of inheritance, segregating with the disease in four family members for three generations, and it was absent in 60 normal controls. We also performed a computational structure modeling of olfactomedin-like domain of myocilin protein and conducted in silico analysis to predict the structural changes in the myocilin protein due to the presence of the mutation. These findings may be important for future diagnosis of other presymptomatic family members, as well as for the increase of the panel of MYOC mutations and their effects on phenotype.  相似文献   
42.
Several studies have revealed that physiological concentrations of biotin are required for the normal expression of critical carbohydrate metabolism genes and for glucose homeostasis. However, the different experimental models used in these studies make it difficult to integrate the effects of biotin deficiency on glucose metabolism. To further investigate the effects of biotin deficiency on glucose metabolism, we presently analyzed the effect of biotin deprivation on glucose homeostasis and on pancreatic islet morphology. Three-week-old male BALB/cAnN Hsd mice were fed a biotin-deficient or a biotin-control diet (0 or 7.2 μmol of free biotin/kg diet, respectively) over a period of 8 weeks. We found that biotin deprivation caused reduced concentrations of blood glucose and serum insulin concentrations, but increased plasma glucagon levels. Biotin-deficient mice also presented impaired glucose and insulin tolerance tests, indicating defects in insulin sensitivity. Altered insulin signaling was linked to a decrease in phosphorylated Akt/PKB but induced no change in insulin receptor abundance. Islet morphology studies revealed disruption of islet architecture due to biotin deficiency, and an increase in the number of α-cells in the islet core. Morphometric analyses found increased islet size, number of islets and glucagon-positive area, but a decreased insulin-positive area, in the biotin-deficient group. Glucagon secretion and gene expression increased in islets isolated from biotin-deficient mice. Our results suggest that biotin deficiency promotes hyperglycemic mechanisms such as increased glucagon concentration and decreased insulin secretion and sensitivity to compensate for reduced blood glucose concentrations. Variations in glucose homeostasis may participate in the changes observed in pancreatic islets.  相似文献   
43.
In this paper, we explore the question, why are striking special skills so much more common in autism spectrum conditions (ASC) than in other groups? Current cognitive accounts of ASC are briefly reviewed in relation to special skills. Difficulties in ‘theory of mind’ may contribute to originality in ASC, since individuals who do not automatically ‘read other minds’ may be better able to think outside prevailing fashions and popular theories. However, originality alone does not confer talent. Executive dysfunction has been suggested as the ‘releasing’ mechanism for special skills in ASC, but other groups with executive difficulties do not show raised incidence of talents. Detail-focused processing bias (‘weak coherence’, ‘enhanced perceptual functioning’) appears to be the most promising predisposing characteristic, or ‘starting engine’, for talent development. In support of this notion, we summarize data from a population-based twin study in which parents reported on their 8-year-olds'' talents and their ASC-like traits. Across the whole sample, ASC-like traits, and specifically ‘restricted and repetitive behaviours and interests’ related to detail focus, were more pronounced in children reported to have talents outstripping older children. We suggest that detail-focused cognitive style predisposes to talent in savant domains in, and beyond, autism spectrum disorders.  相似文献   
44.
Summary We deal with a new variety ofAspergillus which we callAspergillus gracilis Bainiervar. sartoryi (Biourge) Batista, Lima and Vital.This variety appears to be very important under the phylogenetic point of view, apparently being an intermediate form betweenAspergillus andPenicillium.Its morphology resemblesA. gracilis but the conidia characteristics are distinct; we took the epithetsartoryi fromA. sartoryi Biourge which was not described by the respective author.We suggest, too, the transfer of the seriesA. restrictus, where we put our new variety, from the groupA. glaucus, to become independant, as a connective series in the phylogenetic development betweenAspergillus andPenicillium, since the type of the series and the other elements that it embraces does not produce sclerotia or cleistothecia and the conidial apparatus offers curious similarity toPenicillium. Besides, some fungi of the series grow well in certain culture media, in complete discordance with the members of the groupA. glaucus.

Publiçacão no 4

Chefe do Instituto de Micologia;

Diretor do Instituto de Antibióticos e Prof. de Microbiologia da Escola de Química;

Assistente micologista do Instituto de Micologia — (Todos da Universidade do Recife).

Os autores declinam o seu agradecimento ao Dr.Heraldo da Silva maia, Assistente micologista eD. Marilene Maranhão Moreira, Auxiliar-Técnico, do Instituto de Micologia, pela colaboração que lhes prestaram, durante a realização do presente trabalho.  相似文献   
45.
An adrenomyeloneuropathy is observed in a patient died at 24 years old after an illness of five years duration. These case is peculiar by the presence of lamellar cytoplasmic inclusions in the Schwann cells. Adrenomyeloneuropathy is an adult variant of adrenoleucodystrophy. This sex linked recessive disorder is related to an excessive amount of long chain fatty acids.  相似文献   
46.

Background

During the last eight years, North and South Kivu, located in a lake area in Eastern Democratic Republic of Congo, have been the site of a major volcano eruption and of numerous complex emergencies with population displacements. These conditions have been suspected to favour emergence and spread of cholera epidemics.

Methodology/Principal Findings

In order to assess the influence of these conditions on outbreaks, reports of cholera cases were collected weekly from each health district of North Kivu (4,667,699 inhabitants) and South Kivu (4,670,121 inhabitants) from 2000 through 2007. A geographic information system was established, and in each health district, the relationships between environmental variables and the number of cholera cases were assessed using regression techniques and time series analysis. We further checked for a link between complex emergencies and cholera outbreaks. Finally, we analysed data collected during an epidemiological survey that was implemented in Goma after Nyiragongo eruption. A total of 73,605 cases and 1,612 deaths of cholera were reported. Time series decomposition showed a greater number of cases during the rainy season in South Kivu but not in North Kivu. Spatial distribution of cholera cases exhibited a higher number of cases in health districts bordering lakes (Odds Ratio 7.0, Confidence Interval range 3.8–12.9). Four epidemic reactivations were observed in the 12-week periods following war events, but simulations indicate that the number of reactivations was not larger than that expected during any random selection of period with no war. Nyiragongo volcanic eruption was followed by a marked decrease of cholera incidence.

Conclusion/Significance

Our study points out the crucial role of some towns located in lakeside areas in the persistence of cholera in Kivu. Even if complex emergencies were not systematically followed by cholera epidemics, some of them enabled cholera spreading.  相似文献   
47.
We screened the genome of Xanthomonas citri pv. citri strain 306 for tandem repeats. A multiplex polymerase chain reaction protocol was used to assess the genetic diversity of 239 strains of X. citri pv. citri from Asia. The total number of alleles per locus ranged from three to 20. Using pooled data sets, 223 different haplotypes were identified. Successful amplifications were obtained at most loci for seven other X. citri pathovars. This typing scheme is expected to be useful at different spatial scales for population studies of pathovars of X. citri, several of which cause plant diseases of economic importance.  相似文献   
48.
Cultivated surfaces of genetically modified (GM) crops increased year by year, becoming in 2012 more extensive in developed than in industrialized countries. Furthermore, it has been postulated that the plant is which leads to the selection of the microorganisms on its root exudates, creating specific conditions which in turn regulate the specific microbial structure of each plant. In this study, our main objective was to examine whether the introduction of transgenic maize herbicide-tolerant plants will impact the microbial structures that inhabit at the rhizosphere and rhizoplane with respect to conventional hybrid maize plants. Bacterial populations were determined (CFU/g) using four different semi-selective media. The bacterial genera isolated from the rhizoplane and rhizosphere were identified by sequencing its 16S ribosomal DNA. Although minor differences were found in bacterial populations, our results indicated that there was not a strong change of the microorganisms populations that interact at the rhizosphere of an either conventional hybrid or genetically modified maize. However, we found some bacteria that were only isolated in the either genetically modified [Chryseobacterium sp. (4.39%) and Micrococcus sp. (3.72%)] or conventional maize [Sphingobium sp. (13.17%) and Microbacterium sp. (14.81%)].  相似文献   
49.
Sixty root nodule isolates of soybean rhizobia indigenous to eight field sites in India were characterized using PCR-RFLP for repeated sequence RSα a 1195-bp DNA fragment, indole acetic acid production, and nitrogenase activity. Site-dependent variations were observed in terms of IAA production and nitrogenase activities. RSα was conserved in slow-growing soybean rhizobia across locations and sites and was absent in other Rhizobiaceae members and other bacterial genera. The results suggest that RSα can be a useful molecular marker for slow-growing soybean rhizobia. The study also showed the low presence of soybean nodulating fast growers in Indian soils.  相似文献   
50.
Colour signalling traits are often lost over evolutionary time, perhaps because they increase vulnerability to visual predators or lose relevance in terms of sexual selection. Here, we used spectrometric and phylogenetic comparative analyses to ask whether four independent losses of a sexually selected blue patch are spectrally similar, and whether these losses equate to a decrease in conspicuousness or to loss of a signal. We found that patches were lost in two distinct ways: either increasing reflectance primarily at very long or at very short wavelengths, and that species with additional colour elements (UV, green and pink) may be evolutionary intermediates. In addition, we found that patch spectral profiles of all species were closely aligned with visual receptors in the receiver's retina. We found that loss of the blue patch makes males less conspicuous in terms of chromatic conspicuousness, but more conspicuous in terms of achromatic contrast, and that sexual dimorphism often persists regardless of patch loss. Dorsal surfaces were considerably more cryptic than were ventral surfaces, and species in which male bellies were the most similar in conspicuousness to their dorsal surfaces were also the most sexually dimorphic. These results emphasize the consistent importance of sexual selection and its flexible impact on different signal components through evolutionary time.  相似文献   
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