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101.
Root exudates of plants of Vitis vinifera L. cv. Thompson Seedless, grown in nutrient cultures with root temperatures maintained at either 20° or 30° and with shoots at a common air temperature, were assayed for cytokinin activity. After chromatography of freeze-dried sap on paper with n-butanol/acetic acid/water (4:1:1). activity was detected with a soybean callus assay. For both root temperatures, major activity appeared between RF 0.6 and RF 0.8, at about the same concentration in each case. The major difference between the 2 samples was the presence of activity at RF 0.1 to 0.2 in the 20° sample and its absence in the 30° sample.

The higher root temperature resulted in increased shoot and root elongation, increased dry matter accumulation by both shoots and roots, and also altered the morphological appearance of the roots.

  相似文献   
102.
Sequence variation among 10 alleles of the alcohol dehydrogenase (Adh) gene of the Hawaiian drosophilid D. mimica was analyzed with reference to the evolutionary history of the Hawaiian subgroup as well as to levels and patterns of polymorphism of the Adh gene in continental drosophilid species. The Adh gene of D. mimica is less polymorphic than that of other drosophilid species, and no replacement substitutions were found. Statistical analyses of the Adh alleles suggested the action of balancing selection and revealed significant linkage disequilibrium among three of the variable sites. The effective population size was estimated to be only slightly smaller than that of continental species and, surprisingly, on the same order of magnitude as the actual size.   相似文献   
103.
We have discovered a reporter gene insertion that is expressed in the trunk region of Drosophila embryos. Genetic and molecular details of a new regulatory gene neighboring the reporter gene insertion, which we call teashirt (tsh), are described. In situ hybridization of a tsh probe to embryos shows that this gene is expressed in a way similar to the reporter gene. Mutations of tsh show that the gene is required for normal development of the ventral trunk region of embryos, which correlates with the spatial expression of the gene in the anteroposterior axis but not in the dorsoventral axis. Sequencing of a tsh cDNA shows that the putative protein possesses three distantly spaced CX2CX12HX5H zinc finger motifs.  相似文献   
104.

Background

Glutathione S-transferases (GSTs) is a genetic factor for many diseases and exhibits great diversities among various populations. We assessed association of the genotypes of Glutathione S-transferases Omega-1 (GSTO1) A140D with ethnicity in China.

Results

Peripheral blood samples were obtained from 1314 individuals from 14 ethnic groups. Polymorphisms of GSTO1 A140D were measured using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Logistic regression was employed to adjustment for regional factor. The frequency of GSTO1 140A allele was 15.49% in the total 14 ethnic populations. Compared to Han ethnic group, two ethnic populations were more likely to have AA or CA genotype [odds ratio (OR): 1.77, 95% confidence interval (95% CI): 1.05–2.98 for Uygur and OR: 1.78, 95% CI: 1.18–2.69 for Hui]. However, there were no statistically significant differences across 14 ethnic groups when region factor was adjusted. In Han ethnicity, region was significantly associated with AA or CA genotype. Han individuals who resided in North-west of China were more likely to have these genotypes than those in South of China (OR: 1.63, 95% CI: 1.21–2.20).

Conclusion

The prevalence of the GSTO1 140A varied significantly among different regional populations in China, which showed that geography played a more important role in the population differentiation for this allele than the ethnicity/race.  相似文献   
105.
Objectives: The aims of this study were to: (1) investigate patients' views on euthanasia and physician-assisted suicide (PAS), and (2) examine the impact of question wording and patients' own definitions on their responses. Design: Cross-sectional survey of consecutive patients with cancer. Setting: Newcastle (Australia) Mater Hospital Outpatients Clinic. Participants: Patients over 18 years of age, attending the clinic for follow-up consultation or treatment by a medical oncologist, radiation oncologist or haematologist. Main Outcome Measures: Face-to-face patient interviews were conducted examining attitudes to euthanasia and PAS. Results: 236 patients with cancer (24% participation rate; 87% consent rate) were interviewed. Though the majority of participants supported the idea of euthanasia, patient views varied significantly according to question wording and their own understanding of the definition of euthanasia. Conclusions: Researchers need to be circumspect about framing and interpreting questions about support of 'euthanasia', as the term can mean different things to different people, and response may depend upon the specifics of the question asked.  相似文献   
106.
A side effect of radiation therapy in the head and neck region is injury to surrounding healthy tissues such as irreversible impaired function of the salivary glands. Hyperbaric oxygen therapy (HBOT) is clinically used to treat radiation-induced damage but its mechanism of action is largely unknown. In this study, we investigated the molecular pathways that are affected by HBOT in mouse salivary glands two weeks after radiation therapy by microarray analysis. Interestingly, HBOT led to significant attenuation of the radiation-induced expression of a set of genes and upstream regulators that are involved in processes such as fibrosis and tissue regeneration. Our data suggest that the TGFβ-pathway, which is involved in radiation-induced fibrosis and chronic loss of function after radiation therapy, is affected by HBOT. On the longer term, HBOT reduced the expression of the fibrosis-associated factor α-smooth muscle actin in irradiated salivary glands. This study highlights the potential of HBOT to inhibit the TGFβ-pathway in irradiated salivary glands and to restrain consequential radiation induced tissue injury.  相似文献   
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109.
The debate about whether misoprostol should be distributed to low resource communities to prevent post‐partum haemorrhage (PPH), recognised as a major cause of maternal mortality, is deeply polarised. This is in spite of stakeholders having access to the same evidence about the risks and benefits of misoprostol. To understand the disagreement, we conducted a qualitative analysis of the values underpinning debates surrounding community distribution of misoprostol. We found that different moral priorities, epistemic values, and attitudes towards uncertainty were the main factors sustaining the debate. With this understanding, we present a model for ethical discourse that might overcome the current impasse.  相似文献   
110.
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