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161.
All orchids and pyroloids are mycoheterotrophic at least in the early stage. Many species are predisposed to mycoheterotrophic nutrition even in the adult  相似文献   
162.
Three successful cases of artificial insemination in chimpanzees   总被引:2,自引:0,他引:2  
Artificial inseminations were performed on two female chimpanzees from July 1981 to April 1983 and three conceptions were obtained. Semen samples collected by rectal probe method of electroejaculation were incubated at 37 degrees C for about 20 minutes for liquefaction. Liquefied portion of the semen was sucked up into polyethylene tube about 30 cm in length attached to a syringe and was inseminated into cervix of each female of which pelvic region was raised in prone position under anesthesia. Ovulation time was speculated by swelling of sex skin in earlier two cases and by urinary LH level in last case. Three offsprings were obtained 234, 235 and 235 days after last insemination, respectively. All of three show normal developments.  相似文献   
163.
Hepatitis A virus (HAV) has begun to spread globally among men who have sex with men (MSM). Hepatitis E virus (HEV) also may be transmitted through sexual contact among MSM. To assess the current status of these viruses among MSM in Japan, the seroprevalence of both viruses using 503 plasma samples collected between 2009 and 2018 from human immunodeficiency virus (HIV)-positive male donors who were presumed to be mainly MSM was investigated. Our results suggested that HAV may be spreading within this population, as reported elsewhere. By contrast, the spread of HEV was confirmed only among younger HIV-positive donors.  相似文献   
164.
The incidence of hepatitis A virus (HAV) infection has declined significantly worldwide, including in Japan. A nationwide seroepidemiological study on hepatitis A in Japan has taken place almost every 10 years since 1973, and the last study was performed in 2003. In the present study, we describe the latest seroepidemiological pattern of hepatitis A in Japan using 7867 serum specimens obtained from healthy individuals collected between 2013 and 2017, approximately 10 years after the last study. Among them, 223 were anti-HAV positive. About 68% of individuals aged 60 years and older had anti-HAV antibodies, whereas only 1.1% of those aged below 60 years old had immunity; thus, almost all individuals younger than 60 years of age were HAV susceptible. In comparison with previous investigations, the susceptible population has increased and aged. According to data from the National Epidemiological Surveillance of Infectious Diseases (NESID) program, between 1989 and 2016, the proportion of patients with hepatitis A aged 60 years and older continuously increased with each year. The NESID data also suggested that recently, typical large foodborne outbreaks of hepatitis A have become rare, and cases tend to be reported among at-risk groups; overseas travelers contributed to 25% of hepatitis A cases, and in 2018, the first nationwide hepatitis A outbreak that affected mostly men who have sex with men was reported. The purpose of this study was to determine the current status of HAV infection in Japan, based on both seroepidemiology and the national surveillance data from the NESID.  相似文献   
165.
An intensive camera-trapping study and a nutrient analysis were carried out to understand how natural licks are important for mammals in inland tropical rain forests where soil cations are usually depleted. Using camera traps, we investigated the fauna, food habits, and the frequency of visitation by species at five natural licks in the Deramakot forest reserve, Sabah, Malaysia. All food-habit types of mammals (carnivore, herbivore-frugivore, insectivore, and omnivore), which included 29 (78.4%) of 37 species known in Deramakot, were recorded at the natural licks. The sambar deer, followed by the bearded pig, the lesser mouse-deer, the Malay badger, and the orangutan were the most commonly recorded species and represented 77.5% in terms of the frequency of appearance in all photographs taken throughout the year. These results indicated that, although the proportion of species recorded at the natural licks relative to the whole mammalian fauna of the forest was high, the frequency of visitation greatly varied among the species, and only a few species dominated. The frequency of visitation seemed to reflect both the density of species and the demand for the minerals, because some endangered, low-density species were more frequently recorded by cameras than expected—for example, the orangutan which was one of the top five species among natural-lick users. The natural licks with greater concentrations of minerals in seepage soil water were significantly preferred by the sambar deer and the bearded pig than those with lower concentrations of minerals. This result suggests that the chemical properties of soil water in natural licks determine the frequency of visitation of these herbivorous species that have strong demand for minerals.  相似文献   
166.
167.
Suicide rates are higher at high altitudes, and some hypothesize that hypoxia is the cause. There may be a significant correlation between rates of depression and altitude, but little data exist outside the United States. The purpose of the present study is to conduct a survey of depression among the elderly highlanders in Asia. We enrolled 114 persons aged 60 years or older (mean, 69.2 ± 6.7 years; women, 58.8 %) in Domkhar (altitude, 3800 m), Ladakh, India and 173 ethnic Tibetans (mean, 66.5 ± 6.1 years; women, 61.3 %) in Yushu (altitude, 3700 m), Qinghai Province, China. The two-item Patient Health Questionnaire (PHQ-2) and the geriatric depression scale were administered. A psychiatrist interviewed the subjects who had a positive score on the PHQ-2. The results of the interview with the residents conducted by the specialist showed that two cases (1.8 %) from Domkhar and four (2.3 %) from Qinghai had depression. Despite the high altitude, the probability of depression was low in elderly highlander in Ladakh and Qinghai. Our finding seems to indicate that cultural factors such as religious outlook and social/family relationship inhibit the development of depression.  相似文献   
168.
169.
Changes in auditory event related potentials (ERPs) as a function of frequency of tones ranging from 500 Hz to 8,000 Hz were examined under various hypobaric hypoxia conditions of simulated high altitudes up to 6,000 m. A sequence of P1-N1-P2 components, corresponding to those of the human subject, was observed with the monkey's ERPs. These component amplitudes changed as a function of frequency of tone. The relationship revealed an inverted U curve with a maximum amplitude at a tone of 2,000 Hz. The following results under hypoxia were noted: marked reduction of amplitude in ERPs induced by hypoxia linked only to a tone's particular frequency, especially for 2,000 Hz. The delay of latency in the respective components of the ERPs was dependent on the degree of hypoxia. These findings seem to suggest the anatomical bases of the neural generators contributing to each component of the ERPs. This work was supported by the Cooperation Research Program, Primate Research Institute, Kyoto University.  相似文献   
170.

Background  

This cross-sectional and prospective study used a variety of psychological inventories to evaluate the relationship between psychosocial factors and the glycemic control of patients with type 2 diabetes.  相似文献   
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