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1.
In this report we describe the first patient ever found to have azoospermia in association with both exceptional complex chromosomal rearrangements and microdeletions at two translocation breakpoints. A 36-year-old male who had been suffering from male factor infertility was admitted to our clinic. The patient also displayed mild dysmorphia. An analysis of the patient's semen revealed azoospermia. GTG banding revealed the presence of an exceptional complex chromosomal rearrangement involving chromosomes 1, 4, 10 and 14. Using subtelomeric FISH analysis, the patient's karyotype was designated as 46,XY,t(1;10)(q43q44;q21q26.1)(CEB108/T7+,D1S3738-;10PTEL006+,D10S2290+, D1S3738+), ins(14;4) (q31.3;q23q33)(D14S1420+; D4S3359+, D4S2930+). Array-CGH analysis revealed two microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions. We suggest that microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions associated with both an exceptional complex chromosomal rearrangement and the Homo sapiens chromosome 4 open reading frame 37 (C4orf37) gene located at the 4q22.3q23 region might be associated with male factor infertility.  相似文献   
2.
Complex chromosomal rearrangements are very rare chromosomal abnormalities. Individuals with a complex chromosomal rearrangement can be phenotypically normal or display a clinical abnormality. It is believed that these abnormalities are due to either microdeletions or microduplications at the translocation breakpoints or as a result of disruption of the genes located in the breakpoints. In this study we describe a 2-year-old child with mental retardation and developmental delay in whom a de novo apparently balanced exceptional complex chromosomal rearrangement was found through conventional cytogenetic analysis. Using both cytogenetic and FISH analysis, the patient's karyotype was found to be: 46,XY,der(5)t(5;7)(p15.1;7q34),t(5;8)(q13.1;8q24.1)dn. A large, clinically significant deletion which encompassed 887.69 kb was detected at the 5q12.1–5q12.3 (chr5:62.886.523–63.774.210) genomic region using array-CGH. This deleted region includes the HTR1A and RNF180 genes. This is the first report of an individual with an apparently balanced complex chromosomal rearrangement in conjunction with a microdeletion at 5q12.1–5q12.3 in which there are both mental-motor retardation and dysmorphia.  相似文献   
3.
The emerging resistance to artemisinin derivatives that has been reported in South-East Asia led us to assess the efficacy of artemether-lumefantrine as the first line therapy for uncomplicated Plasmodium falciparum infections in Suriname. This drug assessment was performed according to the recommendations of the World Health Organization in 2011. The decreasing number of malaria cases in Suriname, which are currently limited to migrating populations and gold miners, precludes any conclusions on artemether efficacy because adequate numbers of patients with 28-day follow-up data are difficult to obtain. Therefore, a comparison of day 3 parasitaemia in a 2011 study and in a 2005/2006 study was used to detect the emergence of resistance to artemether. The prevalence of day 3 parasitaemia was assessed in a study in 2011 and was compared to that in a study in 2005/2006. The same protocol was used in both studies and artemether-lumefantrine was the study drug. Of 48 evaluable patients in 2011, 15 (31%) still had parasitaemia on day 3 compared to one (2%) out of 45 evaluable patients in 2005/2006. Overall, 11 evaluable patients in the 2011 study who were followed up until day 28 had negative slides and similar findings were obtained in all 38 evaluable patients in the 2005/2006 study. The significantly increased incidence of parasite persistence on day 3 may be an indication of emerging resistance to artemether.  相似文献   
4.
5.
Free-radical-mediated damages may play an important role during metastasis. To investigate their relevance in the metastatic process MDA levels, glutathione peroxidase (GPX) and superoxide dismutase (SOD) activities, and selenium, zinc and copper contents were determined in plasma and erythrocytes from 20 cancerous patients with metastasis and 30 age-matched controls. Significantly higher concentrations of MDA in plasma as well as in erythrocytes were found comparing to the control group. In both plasma and erythrocytes, GPX activity and selenium and zinc levels were significantly lower in patients than in controls. However, SOD activity in erythrocytes and copper levels in both plasma and erythrocytes were significantly higher in patients. The impaired antioxidant system may favor accumulation of free radicals which may induce the process of metastasis. On the other hand, it is possible that the antioxidant system is impaired as a consequence of abnormality in the antioxidative metabolisms due to the cancer process.  相似文献   
6.
Wower IK  Zwieb CW  Guven SA  Wower J 《The EMBO journal》2000,19(23):6612-6621
UV irradiation of an in vitro translation mixture induced cross-linking of 4-thioU-substituted tmRNA to Escherichia coli ribosomes by forming covalent complexes with ribosomal protein S1 and 16S rRNA. In the absence of S1, tmRNA was unable to bind and label ribosomal components. Mobility assays on native gels demonstrated that protein S1 bound to tmRNA with an apparent binding constant of 1 x 10(8) M(-1). A mutant tmRNA, lacking the tag coding region and pseudoknots pk2, pk3 and pk4, did not compete with full-length tmRNA, indicating that this region is required for S1 binding. This was confirmed by identification of eight cross-linked nucleotides: U85, located before the resume codon of tmRNA; U105, in the mRNA portion of tmRNA; U172 in pK2; U198, U212, U230 and U240 in pk3; and U246, in the junction between pk3 and pk4. We concluded that ribosomal protein S1, in concert with the previously identified elongation factor EF-Tu and protein SmpB, plays an important role in tmRNA-mediated trans-translation by facilitating the binding of tmRNA to ribosomes and forming complexes with free tmRNA.  相似文献   
7.
8.
Many kinds of biomass are being tested as a biosorption material for metal removal from the contaminated waters. In the present study the biosorption capacity of an organic solvent tolerant (OST) bacterium was investigated against Cr(VI) and Ni(II). The OST strain of Pseudomonas fluorescens TEM08 was isolated from an oil contaminated soil sample and grown in normal culture conditions (type I) and in the presence of the cyclohexane (type II). Two types of cells were used in the biosorption experiments to compare the organic solvent effect on the biosorption capacity. The biosorption equilibrium was described by Langmuir and Freundlich adsorption isotherms. The value of Q(0) was higher for type I cells (40.8 for Cr(VI); 12.4 for Ni(II)) then the type II (40.7 for Cr(VI); 11.2 for Ni(II)). The adsorption capacity constants (K(F)) of Freundlich model for type I cells and for type II cells were 10.87 and 8.78 for Ni(II) and 13.60 and 10.99 for Cr(VI), respectively.  相似文献   
9.
Emanuel syndrome results from +der(22)t(11q23;22q11). Cleft palate, ear anomalies, heart defects, genital anomalies, hypotonia, and mental retardation are the main features of the syndrome. We report a nine-year-old boy with the t(11;22)(q23;q11) chromosome, transmitted in an unbalanced fashion from his mother, and originated in the maternal grandmother's meiosis. In addition to mental retardation, hypotonia, craniofacial anomalies, and cryptorchidism, he has novel findings such as, joint hyperextensibility, left liver lobe agenesis, left sided malposition of the gallbladder and pancreas hypoplasia. This is the first report associating these features with Emanuel syndrome.  相似文献   
10.

Background

Cytokinin is a plant hormone that plays a crucial role in several processes of plant growth and development. In recent years, major breakthroughs have been achieved in the elucidation of the metabolism, the signal perception and transduction, as well as the biological functions of cytokinin. An important activity of cytokinin is the involvement in chloroplast development and function. Although this biological function has already been known for 50 years, the exact mechanisms remain elusive.

Results

To elucidate the effects of altered endogenous cytokinin content on the structure and function of the chloroplasts, chloroplast subfractions (stroma and thylakoids) from transgenic Pssu-ipt and 35S:CKX1 tobacco (Nicotiana tabacum) plants with, respectively, elevated and reduced endogenous cytokinin content were analysed using two different 2-DE approaches. Firstly, thykaloids were analysed by blue-native polyacrylamide gel electrophoresis followed by SDS-PAGE (BN/SDS-PAGE). Image analysis of the gel spot pattern thus obtained from thylakoids showed no substantial differences between wild-type and transgenic tobacco plants. Secondly, a quantitative DIGE analysis of CHAPS soluble proteins derived from chloroplast subfractions indicated significant gel spot abundance differences in the stroma fraction. Upon identification by MALDI-TOF/TOF mass spectrometry, these proteins could be assigned to the Calvin-Benson cycle and photoprotective mechanisms.

Conclusion

Taken together, presented proteomic data reveal that the constitutively altered cytokinin status of transgenic plants does not result in any qualitative changes in either stroma proteins or protein complexes of thylakoid membranes of fully developed chloroplasts, while few but significant quantitative differences are observed in stroma proteins.  相似文献   
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