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161.
目的观察大鼠糖尿病肾病(diabetic nephropathy,DN)模型的特点和尿LN对早期DN的诊断价值,探讨周脂素(perilipin,Plin)在DN大鼠肾脏中的表达情况。方法将14只SD雄性大鼠随机分为对照组(普通饲料)和糖尿病肾病模型组(高糖高脂饲料),对照组6只,模型组8只,饲养4周后模型组按照30mg/kg剂量注射1%链脲佐菌素(STZ),检测血糖≥16.7mmol/L,糖尿病模型制作成功,继续喂养6周,检测24h尿蛋白≥30mg/kg,糖尿病肾病模型制作成功。考马斯亮蓝检测24h尿蛋白、ELISA测尿层粘连蛋白,HE染色观察肾组织的病理变化,Real-time PCR及Western blot检测肾脏组织中perilipin表达情况。结果模型鼠24h尿蛋白≥30mg/kg,糖尿病肾病大鼠模型制作成功。和对照组大鼠相比,模型组的肾重/体重比明显增高(P<0.05),尿量、尿层粘连蛋白于5周出现升高、24h尿蛋白于6周时出现升高,且三项指标均随着时间不断增高。肾组织病理检查显示:肾小球肥大,基膜增生,微小血管瘤形成,肾小管管腔变形,上皮脱落、空泡样变,大量单核、淋巴等炎性细胞浸润,间质内胶原纤维增生。模型组大鼠肾组织Plin的mRNA及蛋白表达均明显的升高(P<0.05)。结论尿层粘连蛋白比24h尿蛋白升高得早,可作为早期糖尿病肾病的警示指标。Plin表达增高可能参与了糖尿病肾病肾病变过程,为进一步探讨糖尿病肾病的发病机制提供新的思路。  相似文献   
162.
LC-MS/MS has demonstrated potential for detecting plant pathogens. Unlike PCR or ELISA, LC-MS/MS does not require pathogen-specific reagents for the detection of pathogen-specific proteins and peptides. However, the MS/MS approach we and others have explored does require a protein sequence reference database and database-search software to interpret tandem mass spectra. To evaluate the limitations of database composition on pathogen identification, we analyzed proteins from cultured Ustilago maydis, Phytophthora sojae, Fusarium graminearum, and Rhizoctonia solani by LC-MS/MS. When the search database did not contain sequences for a target pathogen, or contained sequences to related pathogens, target pathogen spectra were reliably matched to protein sequences from nontarget organisms, giving an illusion that proteins from nontarget organisms were identified. Our analysis demonstrates that when database-search software is used as part of the identification process, a paradox exists whereby additional sequences needed to detect a wide variety of possible organisms may lead to more cross-species protein matches and misidentification of pathogens.  相似文献   
163.
对比研究孤立性纤维性肿瘤(SFTs)的CT影像学特征及其与病理学的关系,评估CT在SFTs诊断中的应用价值。方法:收集15例孤立性纤维性肿瘤,回顾分析CT表现以及病理形态学和免疫表型变化。结果:15例中6例发生于胸腔内(3例发生于肺,3例位于壁层胸膜);此外鼻腔2例,上颌窦、腹腔、咽旁、腮腺、肾脏、眼眶、髂窝各1例。临床主要表现为局部肿块及其引起的压迫症状,CT扫描显示肿块边界清楚,增强扫描早期呈明显均质性强化。病理学改变显示瘤细胞呈梭形细胞为主,具有细胞密集区与细胞疏松区特征,间质可见瘢痕样的胶原和鹿角样厚壁血管,瘤细胞排列方式多样,免疫组化染色CD34阳性(91.67%), CD99(88.88%),Bcl-2(87.5%)和Vim(100%)。结论:SFT因有完整的包膜,故多为境界清楚的软组织密度肿瘤,如境界不清多提示侵袭性生长。因病理学上肿瘤细胞分布以及有无变性坏死而呈现不同的密度特征,因富血管表现而在增强CT扫描时有较为明显的强化;最终诊断需要免疫组织化学染色证实。  相似文献   
164.
doi: 10.1111/j.1741‐2358.2010.00446.x
Analysis of socio‐demographic and systemic health factors and the normative conditions of oral health care in a population of the Brazilian elderly Objective: To investigate the association of socio‐demographic and systemic health factors according to the normative conditions of oral health care (dental caries, edentulism, periodontal disease and oral mucosal lesion) in elderly individuals. Material and methods: A cross‐sectional study was carried out in a group of elderly with access to community health care (n = 200). The normative conditions of oral health were then investigated according to the WHO and the SB Brazil criteria. Bivariate analyses were evaluated by the chi‐square test and Fisher’s exact test. An estimation of prevalence for the covariates was performed using Poisson’s regression models. Results: The prevalence of edentulism and oral mucosal lesions was detected in 58% and 21.5% of elderly patients, respectively. In the dentate subjects, the prevalence of dental caries and periodontal disease was 51.2% and 20.8%, respectively. Older men and individuals from lower‐income groups exhibited a higher prevalence of dental caries. Elderly women, illiterate individuals, and individuals over the age of 65 years exhibited a higher prevalence of edentulism. Elderly 60–64 years old and those who are employed had a significant association with periodontal disease. Conclusion: Socio‐demographic factors were associated with some notable oral diseases in the elderly.  相似文献   
165.
Human chimeras are potentially invaluable models for hemoprotozoan parasites such as Plasmodium falciparum. The work presented assesses the susceptibility of immunomodulated NOD/LtSz-SCID mice to genetically distinct P. falciparum parasites. To this end, mice grafted with human erythrocytes were inoculated with two P. falciparum laboratory lines, 3D7 and Dd2 and four clinical isolates, ISCIII-230, ISCIII-231, ISCIII-381 and ISCIII-399. The results showed that, without a previous period of parasite adaptation, 100% of the inoculated mice developed an infection, generally self-limited, though some mice died. The parasitemias ranged from 0.05 to 8% and lasted an average of 19 days (15-26 days) depending on the line or isolate studied. Sexual forms of different maturity, stage II-IV and mature gametocytes were observed in the peripheral blood of mice in 22, 50, 25, 72 and 80% of the mice infected with Dd2, ISCIII-399, ISCIII-230, ISCIII-231 and ISCIII-381 isolates, respectively. The study of the clinical symptoms, the haematological parameters and the histopathological changes in the infected mice showed that most of the malaria features were present in the infected mice except that the sequestration of infected erythrocytes was absent or at most a minor phenomenon, as also indicated by the presence of mature forms of the parasites in the peripheral blood. This study shows that the human chimeras allow the complete asexual and sexual erythrocytic cycle of different P. falciparum lines and clinical isolates to be observed in vivo. It opens a new way to investigate any parasite population in terms of infectivity, transmission, and drug resistance.  相似文献   
166.
Indigenous to Europe, the blackberry rust fungus Phragmidium violaceum was introduced to Australia and subsequently appeared in New Zealand, with the most recent authorised introductions to Australia specifically for the biological control of European blackberry. Markers for ‘selective amplification of microsatellite polymorphic loci’ (SAMPL) were developed for studying the population genetics of P. violaceum. Modification of one of the two SAMPL primers with a HaeIII adapter (H) revealed significantly greater levels of genetic variation than primers used to generate AFLPs, the latter revealing little or no variation among 25 Australasian and 19 European isolates of P. violaceum. SAMPL was used to describe genetic variation among these 44 isolates of P. violaceum from 51 loci generated using primer pairs (GACA)4 + H–G and R1 + H–G. The European isolates were more diverse than Australasian isolates, with 37 and 22 % polymorphic loci, respectively. Cluster analysis revealed geographic clades, with Australasian isolates forming one cluster separated from two clusters comprising the European isolates. However, low bootstrap support at these clades suggested that Australian isolates had not differentiated significantly from European isolates since the first record of P. violaceum in Australia in 1984. In general, the results support two hypotheses. First, that the population of P. violaceum in Australia was founded from a subset of individuals originating from Europe. Second, that P. violaceum in New Zealand originated from the Australian population of P. violaceum, probably by wind dispersal of urediniospores across the Tasman Sea. The application of SAMPL markers to the current biological control programme for European blackberry is discussed.  相似文献   
167.
The pathogenic development of the biotrophic ergot fungus Claviceps purpurea is strictly limited to the ovary of grasses. Early colonization stages occur within a defined spatio-temporal course of events, including the directed growth to the vascular tissue for nutrient supply. To characterize mutant strains with putative defects in pathogenicity, the close observation of the infection pathway is therefore indispensable. Here, we describe the establishment of a new pathogenicity assay, based on the in vitro cultivation of isolated rye ovaries. The pathogenic development of a wild-type strain of C. purpurea was compared with the infection of mature rye flowers on whole plants. Up to the sixth day post inoculation, the route of infection within the isolated ovaries was maintained and temporally equal to that seen in mature flowers. Therefore, the in vitro pathogenicity assay is an effective alternative to the whole-plant infection tests, and suitable for detailed infection studies and screening high numbers of mutants for defects in early pathogenesis.  相似文献   
168.
Fusarium pseudograminearum causes crown rot of wheat in Australia and most other wheat growing regions, but its evolutionary history is largely unknown. We demonstrate for the first time that F. pseudograminearum is a single phylogenetic species without consistent lineage development across genes. Isolates of F. pseudograminearum, F. graminearum sensu lato, and F. cerealis, were collected from four countries and four single copy, nuclear genes were partially sequenced, aligned with previously published sequences of these and related species, and analysed by maximum parsimony and Bayesian inference. Evolutionary divergence varied between genes, with high phylogenetic incongruence occurring between the gene genealogies. The absence of geographic differentiation between isolates indicates that the introduction of new fungal strains to a region has the potential to introduce new pathogenic and toxigenic genes into the native population through sexual recombination.  相似文献   
169.
Species of Colletotrichum cause diseases on a wide range of hosts, frequently infecting plants in the Agavaceae (monocotyledons: Liliales). Three species of Colletotrichum restricted to the Agavaceae were detected through morphological studies of specimens and molecular sequence analyses of the LSU of the nu-rDNA and the ITS region of the nu-rDNA from cultures. Colletotrichum agaves on Agave is fully described and illustrated. Colletotrichum dracaenophilum is described as a new species for isolates having long conidia and occurring on Dracaena sanderiana from China. Colletotrichum phormii and Glomerella phormii are determined to be the correct scientific names for the asexual and sexual states, respectively, of a species commonly referred to as C. rhodocyclum and G. phacidiomorpha occurring mainly on Phormium. In addition, C. gloeosporioides and C. boninense were isolated from plants in the Agavaceae. All species of Colletotrichum described on Agavaceae were evaluated based on type specimens. A key to the five species of Colletotrichum on Agavaceae is included. This paper includes one new species, Colletotrichum dracaenophilum, and three new combinations, Colletotrichum phormii, Glomerella phormii, and Phaeosphaeriopsis phacidiomorpha.  相似文献   
170.
Fusarium verticillioides and other Fusarium species were examined for their spore germination phenotypes. In general, germinating spores of F. verticillioides formed germ tubes that immediately penetrated into agar. Such invasive germination was the predominant growth phenotype among 22 examined field isolates of F. verticillioides from a broad range hosts and locations. However, two of the field isolates were unique in that they formed conidial germ tubes and hyphae that grew along the surface of agar before penetration eventually occurred. Conidia of 22 other Fusarium species were assessed for their germination phenotypes, and only some strains of F. annulatum, F. fujikuroi, F. globosum, F. nygamai, and F. pseudoanthophilum had the surface germination phenotype (21 % of the strains assessed). Sexual crosses and segregation analyses involving one of the F. verticillioides surface germination strains, NRRL 25059, indicated a single locus, designated SIG1 (surface vs. invasive germination), controlled the germ tube growth phenotypes exhibited by both conidia and ascospores. Perfect correlation was observed between an ascospore germination phenotype and the germination phenotype of the conidia produced from the resulting ascospore-derived colony. Recombination data suggested SIG1 was linked (7 % recombination frequency) to FPH1, a recently described locus necessary for enteroblastic conidiogenesis. Corn seedling blight assays indicated surface germinating strains of F. verticillioides were less virulent than invasively germinating strains. Assays also indicated pathogenicity segregated independently of the FPH1 locus. Invasive germination is proposed as the dominant form of spore germination among Fusarium species. Furthermore, conidia were not necessary for corn seedling disease development, but invasive germination may have enhanced the virulence of conidiating strains.  相似文献   
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