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1.
Creeping patterns of human adults and infants 总被引:2,自引:0,他引:2
W A Sparrow 《American journal of physical anthropology》1989,78(3):387-401
The patterns of swing and support for the hands-and-feet or hands-and-knees gaits (creeping) of human adults and infants are compared based on data from a number of studies. Human infants show considerable variability in their creeping gait patterns, whereas adult patterns are less variable and fairly consistent after a few minutes of practice. Creeping on hands-and-knees appears to dictate a gait pattern characteristically different from creeping on hands-and-feet. The highly inefficient nature of adult creeping supports the view that our early hominid ancestors were poorly adapted to quadrupedal locomotion. Data obtained from high-speed film analysis of human creeping patterns show that the number of foot lengths per stride in creeping is about twice that for normal upright walking at the same speed. The support pattern of human creeping is different from that of nonhuman primates. These findings are discussed in the context of debate concerning the origin of the Laetoli hominid footprints and the knuckle-walking hypothesis. 相似文献
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Etiological structure of pneumonias in children and adults 总被引:1,自引:0,他引:1
M S Ba?zhomartov O G Stetsenko M A Ba?muratova V A Semenova G U Diuskalieva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1987,(7):16-20
The bacteriological study of sputa, nasopharyngeal smears and bronchial washings taken from pneumonia patients has shown that the leading etiological agent was Streptococcus pneumoniae isolated in the diagnostic titre (10(7) bacteria per ml) in 78.1% of the cases. Staphylococcus aureus, Haemophilus influenzae, enterobacteria and yeast-like fungi have been found to play an insignificant role in the etiology of acute pneumonia (2.5 +/- +/- 0.9%). The results of the serological diagnosis by means of the complement fixation test have revealed that, alongside S. pneumoniae, the following infective agents are of etiological importance in cases of acute pneumonia: respiratory viruses (more than 50%), Mycoplasma pneumonia (10%), Chlamydia psittaci (6.4%) and Legionella pneumophila (3.8%). The study has first revealed that, under the conditions of Alma-Ata, serotypes 19, 23, 8 and 4 prevail among circulating pneumococci. This study has also shown that the use of M. pneumoniae antibody erythrocyte diagnosticum enhances the detection rate of mycoplasma infections in pneumonia patients. 相似文献
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Diapausing fertilized adults 总被引:5,自引:0,他引:5
Summary A lake population of the cyclopoid copepod Cyclops strenuus Fischer had a 1-year life cycle including a diapause from June to January. Dormant stages consisted of fertilized females, not previously described as a diapause stage, and a small fraction of cop V. The longevity of the sperm in a diapausing female was at least 6–7 months. Pre-fertilization is assumed to be an adaptive mechanism to assure fertilization when male abundance is low. This life cycle pattern also gives a shorter time-lag between diapause break and offspring development, and also the low total adult population exerts a lower predation pressure on their offspring. The flexibility of life cycle patterns of copepods is emphasized. 相似文献
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Drag characteristics of competitive swimming children and adults 总被引:3,自引:0,他引:3
The aims of this study were to compare drag in swimming children and adults, quantify technique using the technique drag index (TDI), and use the Froude number (Fr) to study whether children or adults reach hull speed at maximal velocity (vmax). Active and passive drag was measured by the perturbation method and a velocity decay method, respectively, including 9 children aged 11.7+/-0.8 and 13 adults aged 21.4+/-3.7. The children had significantly lower active (kAD) and passive drag factor (kPD) compared with the adults. TDI (kAD/kPD) could not detect any differences in swimming technique between the two groups, owing to the adults swimming maximally at a higher Fr, increasing the wave drag component, and masking the effect of better technique. The children were found not to reach hull speed at vmax, and their Fr were 0.37+/-0.01 vs. the adults 0.42+/-0.01, indicating adults' larger wave-making component of resistance at vmax compared with children. Fr is proposed as an evaluation tool for competitive swimmers. 相似文献
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Jong-Yil Chai Young-Je Kang Sung-Yil Choi Sang-Mee Guk Jae-Ran Yu Soon-Hyung Lee 《The Korean journal of parasitology》1998,36(4):217-225
A scanning electron microscopic study was performed to observe surface ultrastructures of excysted metacercariae and adults of Metagonimus miyatai. Metacercariae were collected from the scale of the pale chub (Zacco platypus), and adult flukes were harvested 1-4 weeks after infection to rats. In excysted metacercariae, the oral sucker was devoid of tegumental spines and had type I and type II sensory papillae. Anteriorly to the ventral sucker, spines were dense and digitated into 5-7 points, whereas near the posterior end of the body spines were sparse and digitated into 2-3 points. In one-week adults, 7 type II sensory papillae were arranged around the lip of the oral sucker, and at inner side of the lip one pair of small and two pairs of large type 1 sensory papillae were seen on each side. The distribution of tegumental spines was similar to that of metacercariae, but they were more differentiated with 9-11 pointed tips. In two- to four-week old adults, the surface ultrastructure was nearly the same as in one-week old adults, however, sperms were frequently seen entering into the Laurer''s canal. Conclusively, the surface ultrastructure of M. miyatai was generally similar to that of M. yokogawai, however, differentiation of tegumental spines and distribution of sensory papillae around the oral sucker were different between the two species, which may be of taxonomic significance. 相似文献
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Chai JY Guk SM Han ET Seo M Shin EH Sohn WM Choi SY Lee SH 《The Korean journal of parasitology》2000,38(1):9-15
A scanning electron microscopic study was performed on the surface ultrastructure of metacercariae and adults of Metagonimus takahashii. Metacercariae were collected from the scale of crucian carp (Carassius auratus), and adult flukes were harvested 1-4 weeks after infection to rats. In excysted metacercariae, the oral sucker had type I (numerous) and type II (seven in total) sensory papillae. Tegumental spines were dense and digitated into 5-7 points on the surface anterior to the ventral sucker, but became sparse and less digitated posteriorly toward the end of the body. In adults, seven type II sensory papillae were characteristically arranged around the lip of the oral sucker, and on the inner side of the lip four small and two large type I sensory papillae were symmetrically seen on each side (12 in total). Tegumental spines on anterior two-thirds of the body, were digitated with 9-12 tips ventrally and 8-13 tips dorsally. Sperms entering into the Laurer's canal were observed. The results show that the surface ultrastructure of M. takahashii is generally similar to those of M. yokogawai and M. miyatai except for the digitation of tegumental spines. 相似文献
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D. A. APANASKEVICH K. O. BANDARANAYAKA M. A. APANASKEVICH R. S. RAJAKARUNA 《Medical and veterinary entomology》2016,30(3):330-341
Amblyomma integrum Karsch, 1879 (Acari: Ixodidae) is one of four Amblyomma Koch, 1844 species with eyes found in southern India and Sri Lanka. The immature stages of this species were poorly described. Therefore, accurate identification is difficult. Here we re‐describe the male, female, nymph and larva of A. integrum and illustrate all the stages in greater detail for the first time. A set of diagnostic morphological characters is defined to distinguish this species from other sympatric species of eyed Amblyomma in any parasitic stage of development. Adults of A. integrum parasitize mostly various larger mammals whereas nymphs and larvae use mostly larger and medium mammals. Amblyomma integrum is recorded from India (Andhra Pradesh, Goa, Karnataka, Orissa and Tamil Nadu States) and throughout Sri Lanka. 相似文献
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Shawn D. Aaron Katherine L. Vandemheen Louis-Philippe Boulet R. Andrew McIvor J. Mark FitzGerald Paul Hernandez Catherine Lemiere Sat Sharma Stephen K. Field Gonzalo G. Alvarez Robert E. Dales Steve Doucette Dean Fergusson for the Canadian Respiratory Clinical Research Consortium 《CMAJ》2008,179(11):1121-1131
Background
It is unclear whether asthma is overdiagnosed in developed countries, particularly among obese individuals, who may be more likely than nonobese people to experience dyspnea.Methods
We conducted a longitudinal study involving nonobese (body mass index 20–25) and obese (body mass index ≥ 30) individuals with asthma that had been diagnosed by a physician. Participants were recruited from 8 Canadian cities by means of random-digit dialing. A diagnosis of current asthma was excluded in those who did not have evidence of acute worsening of asthma symptoms, reversible airflow obstruction or bronchial hyperresponsiveness, despite being weaned off asthma medications. We stopped asthma medications in those in whom a diagnosis of asthma was excluded and assessed their clinical outcomes over 6 months.Results
Of 540 individuals with physician-diagnosed asthma who participated in the study, 496 (242 obese and 254 nonobese) could be conclusively assessed for a diagnosis of asthma. Asthma was ultimately excluded in 31.8% (95% confidence interval [CI] 26.3%–37.9%) in the obese group and in 28.7% (95% CI 23.5%–34.6%) in the nonobese group. Overdiagnosis of asthma was no more likely to occur among obese individuals than among nonobese individuals (p = 0.46). Of those in whom asthma was excluded, 65.5% did not need to take asthma medication or seek health care services because of asthma symptoms during a 6-month follow-up period.Interpretation
About one-third of obese and nonobese individuals with physician-diagnosed asthma did not have asthma when objectively assessed. This finding suggests that, in developed countries such as Canada, asthma is overdiagnosed.Between 1980 and 1994, the age-adjusted prevalence of asthma increased by 75% in Canada and the United States.1,2 The prevalence of both the symptoms and diagnosis of asthma may depend heavily on an awareness of asthma in the population studied.3 In recent decades, awareness of asthma has increased significantly among patients and their physicians. Part of this awareness has been stimulated by the medical community and part by the pharmaceutical industry, which has developed new medications for asthma and has directly or indirectly advertised these medications to patients and health care providers.3 In Scotland, the proportion of children reporting asthma symptoms who received a diagnosis of asthma from their physicians increased from 28% in 1964 to 64% in 1999.4 Part of the increase in prevalence may be attributable to changes in diagnostic labelling.Over the past 3 decades, the incidence and prevalence of obesity has increased concurrently with the incidence and prevalence of asthma, which indicates a possible link between obesity and asthma.5–7 Studies have suggested that asthma is almost twice as likely to be diagnosed in obese people as in nonobese people. In Canada and the United States, 8.8%–9.2% of obese adults reported having received a diagnosis of asthma from a physician, as compared with 4%–5% of nonobese adults.8,9It is unclear whether this increased tendency to diagnose asthma in patients with respiratory symptoms is appropriate, or whether asthma may be overdiagnosed in developed countries. Potential overdiagnosis of asthma may be even more pronounced among obese people. Obesity decreases chest wall compliance, which results in reduced lung volumes, increased work of breathing and increased energy and oxygen costs of breathing.10–12 Because obese patients report more dyspnea and asthma-like symptoms than nonobese patients, they may be more likely to be misdiagnosed by their physicians as having asthma.We conducted this study to determine the proportion of obese and nonobese Canadian adults who have an incorrect diagnosis of asthma. We also assessed whether overdiagnosis of asthma was more prevalent among obese than among nonobese individuals. Finally, we determined what proportion of obese and nonobese patients could safely discontinue their asthma medications once a diagnosis of asthma was excluded. 相似文献11.
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Cavazzana-Calvo M André-Schmutz I Lagresle C Fischer A 《Comptes rendus biologies》2002,325(10):1053-1058
In the last 30 years, allogeneic bone marrow transplantation has become the treatment of choice for many hematologic malignancies or inherited disorders and a number of changes have been registered in terms of long-term survival rate of transplanted patients as well as of available sources of hematopoietic stem cell (HSC). In parallel to the publication of better results in HSC transplantation, several recent discoveries have opened a scientific and ethical debate on the therapeutical potential of stem cells isolated from adult or embryonic tissues. One of the major discoveries in this field is the capacity of bone marrow-derived stem cells to treat a genetic liver disease in a mouse model, thus justifying the concept of transdifferentiation of adult stem cell and raising hopes on its possible therapeutical applications. We have tried here to summarise the advances in this field and to discuss the limits of these biological data. 相似文献
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探讨新疆柯尔克孜族成人体型特点及其规律,并分析该族群在不同地区(南、北疆)体型的差异性。应用人体测量法,在知情同意原则的基础上,2017年7月至2018年8月,随机抽取新疆南疆和北疆地区柯尔克孜族成人作为调查对象,共计1270名(男551名,女719名)。按年龄、性别、地区分组,对所有调查对象的身高、体质量等10项指标进行了测量,并应用Heath-Carter体型评价法进行体型判定。研究发现,南疆地区柯尔克孜族成人体型具有性别间的差异;南、北疆柯尔克孜族成人体型存在地区间的差异;从体型上看柯尔克孜族与汉族较相似。 相似文献
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Jingwen Ye Fanghua Chai Xinghui Gu Shichou Han Xin Lü Sigui Ji 《Biocontrol Science and Technology》2019,29(1):103-106
Technology for mass storage is one of the most important issues facing the use of parasitoids for biological control programmes. The emergence rate, the proportion of females, adult longevity, parasitism rate of Aphidius gifuensis after cold storage of mummies at 5°C for different time periods, and the effect of different diets on their longevity were assessed. The results indicated that 10–30 days was a suitable period for cold storage at 5°C, but that 20 days was optimal. The 5% glucose solution was a successful food supplement for A. gifuensis. These results are important to the commercial exploitation of this economically important parasitic wasp. 相似文献
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RAPER FP 《Proceedings of the Royal Society of Medicine》1958,51(9):781-782
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Characterizing upper limb muscle volume and strength in older adults: a comparison with young adults
Aging is associated with the loss of muscle volume (MV) and force leading to difficulties with activities of daily living. However, the relationship between upper limb MV and joint strength has not been characterized for older adults. Quantifying this relationship may help our understanding of the functional declines of the upper limb that older adults experience. Our objective was to assess the relationship between upper limb MV and maximal isometric joint moment-generating capacity (IJM) in a single cohort of healthy older adults (age ≥ 65 years) for 6 major functional groups (32 muscles). MV was determined from MRI for 18 participants (75.1±4.3 years). IJM at the shoulder (abduction/adduction), elbow (flexion/extension), and wrist (flexion/extension) was measured. MV and IJM measurements were compared to previous reports for young adults (28.6±4.5 years). On average older adults had 16.5% less total upper limb MV compared to young adults. Additionally, older adult wrist extensors composed a significantly increased percentage of upper limb MV. Older adult IJM was reduced across all joints, with significant differences for shoulder abductors (p<0.0001), adductors (p=0.01), and wrist flexors (p<0.0001). Young adults were strongest at the shoulder, which was not the case for older adults. In older adults, 40.6% of the variation in IJM was accounted for by MV changes (p≤0.027), compared to 81.0% in young adults. We conclude that for older adults, MV and IJM are, on average, reduced but the significant linear relationship between MV and IJM is maintained. These results suggest that older adult MV and IJM cannot be simply scaled from young adults. 相似文献
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Christian Paschen Karl Reiter Franz Stanzel Helmut Teschler Matthias Griese 《Respiratory research》2005,6(1):138