首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   24篇
  免费   1篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2010年   1篇
  2007年   4篇
  2006年   2篇
  2005年   1篇
  2003年   1篇
  2002年   1篇
  1999年   1篇
  1993年   1篇
  1991年   1篇
  1990年   1篇
  1987年   1篇
  1986年   1篇
  1984年   1篇
  1973年   1篇
  1969年   2篇
  1968年   1篇
  1967年   1篇
排序方式: 共有25条查询结果,搜索用时 390 毫秒
1.
Dynamics of physiological and psychological characteristics of healthy volunteers (adolescents and adults), speech professionals (logopedics), and stutter patients (adolescents and adults) in process of adoptive self-regulation with biofeedback on objective physiologic indicator - changes of respiratory arrhythmia of hart rate were investigated. High level of efficacy and practicability of the method application was revealed to study, diagnostics, optimization and correction of breathing, speech and behavior.  相似文献   
2.
Cross immunoelectrophoresis was used to study antigenic composition of the brain of rats preferring water, or 15% ethanol and of intermediate group animals. The rat brain showed 6 antigens, one of them was found to be neurospecific. The intermediate group animals and those preferring ethanol differed from those preferring water in that they demonstrated two antigens which were found to be neuro-nonspecific. The content of the neurospecific protein S-100 in the cerebellum measured by rocket immunoelectrophoresis was demonstrated to be the same in animals preferring water and ethanol. A single intraperitoneal injection of 25% ethanol (2.5 g/kg) to the intermediate group rats brought about a change in the composition of neuro-nonspecific soluble antigens of the brain.  相似文献   
3.
4.
The glutathione-dependent system of antioxidant defense was studied in the chorionic and placental tissues of women with miscarriage. In the case of spontaneous abortion, the level of glutathione peroxidase reached the maximum even in trimester I and remained more than 1.5-fold higher during the whole gestation period than in the placental tissue of women with physiological pregnancy and delivery. The activity of glutathione reductase in miscarriage was insignificantly different from that in the control group. The activity of glutathione S-transferase in miscarriage was similar to that in the control group during trimester I and remained low during the whole gestation, contributing to a decrease in nonspecific defense in the mother-placenta-fetus system, leading to pathology of the fetus and infant. It is concluded that oxidative stress in the placental tissues is an essential pathogenic factor of miscarriage.  相似文献   
5.
Background: Recent research suggested that cancer survival has improved in recent cohorts. Improvement in cancer survival is considered a valid indicator of the quality of care introduced to the patients. The aim of this study is to investigate the changes in the survival profile over age for patients with the most incident cancers. Methods: Survival data of 3.94 million patients diagnosed with 23 primary-site cancers within the periods of 1979–1983, 1989–1993, and 1999–2003 were adopted from the Surveillance, Epidemiology and End Results database. Gender and cause-specific survival probabilities were estimated at one, three, and five years after diagnosis using the Kaplan–Meier survival estimate. Survival was presented for each of the studied cancers, cohorts, and sexes in the form of line graphs as a function of age at diagnosis. Error bars demonstrated the probability of error at 95% confidence level. Results: The graphs demonstrated that cancer survival was improved over the successive cohorts for most cancers, with several exceptions such as brain and lung cancers. The relation between survival and the age at diagnosis was generally described in the form of a gradual decline phase and a rapid fall-off phase at 70–80 years of age, with few exceptions as in leukemia and Hodgkin lymphoma. Patients who survived for three years were more likely to live for five years after diagnosis, but this prediction could not be extrapolated to the one-year survivors. Conclusion: Further studies on tumor-specific characteristics and treatment modalities of these patients are suggested for clarification of the possible causes of variations in patient's survival profile over age.  相似文献   
6.
A code for calculations of electron, ion and photon radiation action on tissue-equivalent matter (water vapor) by the Monte Carlo technique is presented. The new fluctuation detector method is efficient in evaluating of probability distributions and moments of absorbed energy and number of ionizations in small sites. Spatial and energy distributions of particles fluences and fluctuation characteristics of radiation action on spherical and thread-like sites of nanometer diameter are compared with various experimental and theoretical data and discussed. Non-equivalence of energy absorption and ionization events and consequences of that non-equivalence are numerically analysed. As an example of radiobiological application the yield of single- and double-strand breaks of DNA is calculated in a threshold model.  相似文献   
7.
Parasite stages of Symbiocladius rhithrogenae (Zavrel, 1924) (Diptera: Chironomidae) were found in several streams from the Rila Mountain. A total of 19 sites (18 from the Iskar River and one from the Struma River catchments) were sampled, from which the parasite was recorded only in four (Levi Iskar, Rilska, Malyovishka and Cherni Iskar Rivers). Both pupa and larvae of S. rhithrogenae were found attached only to mayfly larvae of the genus Rhithrogena Eaton, 1881, while other Heptageniidae species were ignored. This specialisation could be connected to an overlap between the seasonal cycles of the parasite and its host. We discussed the bioindicative potential of S. rhithrogenae.  相似文献   
8.
Activity of Cu,Zn-superoxide dismutase (SOD) in old rats' brain was found to be decreased by 46.8% as compared to young animals. The brain concentration of Schiff bases (SB) was decreased by 13.6% in old rats, whereas concentration of diene conjugates (DC), protein peroxidation (PP), and total antioxidative activity (TAA) was the same in old as well as in young rats. The liver level of the DC and TAA was also the same. The serum level of the PP, SB, and DC was increased whereas the activity of the SOD and TAA was decreased in old rats. The findings suggest occurrence of considerable age-related changes in free radical processes as well as the organ specifics of these changes in rats.  相似文献   
9.
The basal eudicot Aquilegia (columbine) has an unusual floral structure that includes two morphologically distinct whorls of petaloid organs and a clearly differentiated fifth organ type, the staminodium. In this study, we have sought to determine how Aquilegia homologs of the B class genes APETALA3 (AP3) and PISTILLATA (PI) contribute to these novel forms of organ identity. Detailed expression analyses of the three AP3 paralogs and one PI homolog in wild-type and floral homeotic mutant lines reveal complex patterns that suggest that canonical B class function has been elaborated in Aquilegia. Yeast two-hybrid studies demonstrate that the protein products of Aquilegia's AP3 and PI homologs can form heterodimers, much like what has been observed for their core eudicot homologs. Downregulation of AqvPI using virus-induced gene silencing indicates that in addition to petal and stamen identity, this locus is essential to staminodial identity but may not control the identity of the petaloid sepals. Our findings show that preexisting floral organ identity programs can be partitioned and modified to produce additional organ types. In addition, they indicate that some types of petaloid organs are not entirely dependent on AP3/PI homologs for their identity.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号