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1.
中国与日本旧石器时代晚期人类的关系   总被引:2,自引:2,他引:0  
吴新智 《人类学学报》1988,7(3):235-238
按照歧异系数,柳江人与港川人很接近,其程度和港川人二女性之间或山顶洞二女性之间接近的程度相似,柳江人与山顶洞人相去较远,山顶洞人与港川人相去较远,身材的比较也支持这些看法。  相似文献   

2.
Langerin mediates the carbohydrate-dependent uptake of pathogens by Langerhans cells in the first step of antigen presentation to the adaptive immune system. Langerin binds to an unusually diverse number of endogenous and pathogenic cell surface carbohydrates, including mannose-containing O-specific polysaccharides derived from bacterial lipopolysaccharides identified here by probing a microarray of bacterial polysaccharides. Crystal structures of the carbohydrate-recognition domain from human langerin bound to a series of oligomannose compounds, the blood group B antigen, and a fragment of β-glucan reveal binding to mannose, fucose, and glucose residues by Ca2+ coordination of vicinal hydroxyl groups with similar stereochemistry. Oligomannose compounds bind through a single mannose residue, with no other mannose residues contacting the protein directly. There is no evidence for a second Ca2+-independent binding site. Likewise, a β-glucan fragment, Glcβ1-3Glcβ1-3Glc, binds to langerin through the interaction of a single glucose residue with the Ca2+ site. The fucose moiety of the blood group B trisaccharide Galα1-3(Fucα1-2)Gal also binds to the Ca2+ site, and selective binding to this glycan compared to other fucose-containing oligosaccharides results from additional favorable interactions of the nonreducing terminal galactose, as well as of the fucose residue. Surprisingly, the equatorial 3-OH group and the axial 4-OH group of the galactose residue in 6SO4-Galβ1-4GlcNAc also coordinate Ca2+, a heretofore unobserved mode of galactose binding in a C-type carbohydrate-recognition domain bearing the Glu-Pro-Asn signature motif characteristic of mannose binding sites. Salt bridges between the sulfate group and two lysine residues appear to compensate for the nonoptimal binding of galactose at this site.  相似文献   

3.
贵州桐梓新发现的人类化石   总被引:2,自引:2,他引:0  
本文主要描述1983年在贵州桐梓县岩灰洞新发现的四枚人类牙齿化石,并对1972年在该洞发现的两枚人类牙齿一并作进一步的讨论。经研究表明,它们的形态特征与北京猿人非常相似,而与早期智人有着明显的差异。因此,我们认为桐梓人类化石似应属直立人(Homoerectus),而不是以前认为的早期智人(early Homo sapiens)。该遗址的地质时代为更新世中期。  相似文献   

4.
The peculiar combination of all the characters of the Azyky cave, where a mandible fragment has been found, permit to isolate the Azykh man as a special local variant of chronologically early palaeoanthropus and to name him “Palaeoanthropus azykhensis”. The discovery of the Udabnopitek at the Western border of Azerbaijan and of the Pre-Chellean culture in the Azykh cave gives subtantial evidence to the fact that the territori of the Eastern Transcaucasus is the part of the vast region where the umanization of ape took place.  相似文献   

5.
1. A microsomal enzyme preparation from the yeast Saccharomyces cerevisiae catalyzes the transfer of mannosyl units from GDPmannose to mannose and a number of mannose-containing oligosaccharides and glycosides whereby different glycosidic bonds are formed.2. Of the compounds tested besides mannose, only those containing an α-linked mannosyl unit at the nonreducing position of their moleculae were effective as receptors. Monodeoxyanalogues of mannose as well as α-mannose phosphates did not serve as receptors in the above reaction.3. The structure of the product formed with mannose as receptor was determined to be O-α-D-mannosyl-(1→2)-mannose; with αMan(1→Man(1→6)mannose as the acceptor, the product was αMan(1→6)αMan(1→6)mannose and with αMan-(1→2)mannose the product was tentatively characterized as a mixture of αMan-(1→3)αMan(1→2)mannose and αMan(1→2)αMan(1→2)mannose.4. The enzymes catalyzing the formation of different types of glycosidic bonds differed in their acceptor specificity, pH-activity curves and rates of heat denaturation.5. Radioactive disaccharids were unable to enter the mannan protein molecule in the cell-free system while free radioactive mannose did incorporate into polysacchride to a minor extent under the same conditions.  相似文献   

6.
In approaching the taxonomy of Neolithic Man and its phylogenetic relationship to Later Paleolithic Man and Modern Man in China, the statistical methods used here are Penrose's shape distance and PCA (Principal Component Analysis). The scattergram based on principal component scores, combines the dendrogram based on Penrose's shape distance, and takes the male taxonomy into main consideration, but takes the female taxonomy — as a reference only because the differentiations in physical characteristics among male populations generally are rather larger than those among the female populations. Thus according to this scattergram, Neolithic Man in China can be divided into two large groups: the Northern China group, and the Southern China group. The theory is that in Hengzhen there exist some blood mixtures between the Southern China Group and the Northern China Group (especially the third subgroup) of Neolithic Man. Later Paleolithic Man of China — Liujiang and Upper-Cave Man — can also clearly distinguished from the rest of Neolithic Man in China in the scattergram, and can be considered as two different local types of Later Paleolithic Man. So-called “Negro-Australoid” racial traits can themselves be doubtlessly traced back to Later Paleolithic Man of China — Liujiang and Upper-cave Man. These traits are the intrinsic characteristics of Neolithic Man in China and only then is there slight difference in the extent of the manifestation of these traits in the population.  相似文献   

7.
Norin E 《Anaerobe》2011,(6):431-432
When investigating different disturbances of the normal intestinal flora causing disorders and/or diseases in man and animal, these studies include comparisons of results with control materials, i.e., materials from conventional laboratory animals or healthy human beings. However, how "normal" is the control group’s flora? In this paper two different examples will be discussed; one investigation with laboratory animals and one from a human study.  相似文献   

8.
In 28 subjects the cardiovascular response to repeated stimulation was monitored during six daily sessions. Calf blood flow was measured with mercury-in-silastic venous occlusion plethysmography, blood pressure with electronic sphygmomanometer. The stimuli used were: 1 kHz sound of 90 dB and 100 dB intensity and immersion of one foot for 60 s in water at 4 degrees C. Initially sounds induced large vasodilatation in the calf, immersion of one foot in the water induced in the contralateral calf vasodilatation in one group and vasoconstriction in another group of subjects. The blood pressure changes were less prominent and less consistent. After the first session of repeated stimulation the vascular response during the second session was significantly diminished. The reduction of the vasodilatation was the most rapid. During the remaining 5 days the responses were suppressed. It has been established that in the patients in the initial stage of hypertension the ability to habituate vascular response is impaired (Zbrozyna and Krebbel 1985). It is therefore suggested that the test of the ability for long-term vascular habituation could be used as a supplementary diagnostic test.  相似文献   

9.
山西“丁村人”生活时期的古气候   总被引:1,自引:0,他引:1  
陈万勇 《人类学学报》1983,2(2):184-195
本文通过对丁村一带晚更新世沉积物进行差热分析、X射线衍射、重矿物、化学分析、pH值、有机质的分析,结合其他动、植物化石资料,研究“丁村人”生活时期的气候变迁。  相似文献   

10.
Summary Recent physiological studies have indicated an autonomic influence on the secretion of testosterone from Leydig cells in humans and laboratory animals. Furthermore, a few studies have shown enhanced autonomic control of Leydig cell function in immature, relative to mature, laboratory animals. In the current ultrastructural study of the human testicular interstitium the morphology of autonomic components is described from neonatal, childhood and pubertal ages. Autonomic nerve fibers and varicosities with neurotransmitter vesicles are described in proximity to Leydig cells. The observed autonomic terminals are classified by vesicle morphology into three general types: (1) Type I with predominately small agranular vesicles (30–60 nm) and occasional larger granular vesicles (100 nm). This type is morphologically consistent with being cholinergic. (2) Type II with predominately small granular vesicles (30–60 nm), as well as sporadic large granular vesicles. These are morphologically consistent with adrenergic terminals. (3) Type III which exhibit numerous large granular vesicles of mixed size. Evidence of autonomic terminals is encountered most frequently in childhood biopsies, age 3 to 10 years. The neonatal specimen (4 months) is noteworthy in that many of the Schwann cells appear immature and no adrenergic terminals are observed. In contrast, terminals morphologically consistent with being adrenergic are common in the childhood series of biopsies. Although the vast majority of the autonomic terminals are associated with Leydig cells indirectly as boutons en passant, separated by approximately 150 nm to more than a m, evidence of direct contact (20 nm) of autonomic terminals with Leydig cells is presented. These findings provide morphological evidence of frequent indirect and rare direct contact of autonomic nerve terminals with Leydig cells in man.  相似文献   

11.
钱方 《人类学学报》1985,4(4):324-332
通过对元谋组进一步研究,同时综合地层、古生物化石、磁性地层、元谋人牙齿化石及新构造运动等方面材料,对元谋组时代进行了探讨,证明元谋组时代为早更新世。 元谋人化石产于元谋组的第四段25层中。地层层次清晰,没有紊乱,磁性地层重新研究得出第四段的磁极性相当松山反向期中的奥都维事件附近,元谋人的年代仍为距今170万年左右,而不是刘东生等认为的50—60万年。  相似文献   

12.

1. 1.The forearm of 5 female subjects ws thermally stimulated by 2 sets of interposed servo-thermodes that respectively drove skin temperature at ±0.1°C.s−1 for 25 s and then held it constant. Mean skin temperature remained constant. The sequence was repeated at adapting temperatures between 22.5 and 37.5°C.

2. 2.Thermal sensations, continuously reported by the position of a dial, were warmer for heterogeneous thermal stimuli than for homogeneous stimuli when mean skin temperature was greater than 30°C and cooler when less than 27.5°C.

3. 3.This phenomenon is inconsistent with a single additive contribution of “warm” and “cold” information to thermal sensations.

Author Keywords: Man; thermal sensation; skin temperature  相似文献   


13.
The comparative study of the karyotypes of Microcebus (Lemur, Cheirogaleid) and Cebus (Platyrrhini, Ceboid) shows important similarities between nearly all large chromosomes of these two genera. Since a relationship has been previously found between the Karyotypes of Homo and Cebus, a correspondence may be found between many chromosomes of man and those of Lemurs. This study enlarges the filed of comparative cytogenetics at the level of the primate order.  相似文献   

14.
Summary Serial section analysis has demonstrated that ring-shaped nucleoli of mature human lymphocytes are spherical structures consisting of a peripheral ribonucleoprotein shell that surrounds one large fibrillar center. The shell exhibits usually one or, less frequently, two openings. The fibrillar center is in contact with the nucleoplasm and perinucleolar condensed chromatin, which frequently appears as a pedicle-like structure. Several chromocenters are associated with the ring-shaped nucleolus.  相似文献   

15.
《L'Anthropologie》2021,125(2):102857
Very old Upper Paleolithic is here considered as one of the origins of equivalent traditions in European Continent.  相似文献   

16.
巢县人年代位置新证据及其意义   总被引:8,自引:3,他引:5  
本文银山地点钟乳石和骨石样的铀系年代。根据位于第2层顶部一钙板样3次分析的平均值,巢县人的上限年龄应为31万年,据此似可将这一人类化石从目前分类的早期智人改划为晚期直立人。讨论了钟乳石铀系年代的可信度。银山下部地层骨化石样的分析结果,可引为二法一致的骨化石铀系年龄不足以保证数据真实的例证。  相似文献   

17.
张银运 《人类学学报》1991,10(3):270-271
《维尔泰斯佐洛斯地点、人和文化》(Vertesszlls Site,Man and Culture)一书由Mikls Kretzoi和Viola T.Dobosi编,1990年于匈牙利布达佩斯由Akademiai Kiad出版。 我国古人类学界对维尔泰斯佐洛斯这一地点名并不陌生,几乎都知道在这个匈牙利化石地点于1965年曾经发现一块人类枕骨化石和N枚人类牙齿化石。据说这些人类化石的年代相当古老,大致上可与我国周口店发现的直立人的年代相当,但其形态却带有不少进步性质。因而,维尔泰斯佐洛斯化石人到底属于直立人或是智人,学术界一直有不同的意见。除了这些情况之外,我国许多人对维尔泰斯佐洛斯地点的详情就了解甚少,这可能是由于有关该地点及其发现物的报道多以我们所不熟悉的文字发表或发表在我们难以读到的刊物上的缘故。《维尔泰斯佐洛斯地点、人和文化》一书英文本的出版,肯定会受到我国同行们的欢迎。  相似文献   

18.
Heterogeneity of epithelial cells in the human thymus   总被引:9,自引:0,他引:9  
Summary To evaluate interrelationships among epithelial cells, and between morphology and function in the microenvironment, we studied the ultrastructural morphology of epithelial cells in sections of human thymus from donors aged 2 months to 31 years. Six types of epithelial cells were observed: subcapsular-perivascular (type 1); pale (type 2); intermediate (type 3); dark (type 4); undifferentiated (type 5); and large-medullary (type 6). Cells of types 2, 3 and 4 were found throughout the organ. The type-2 to -4 epithelial cells may represent various stages in a differentiation process. In this, type-2 cells are very active and type-4 cells are possibly degenerating elements. Type-4 cells can also contribute to Hassall's corpuscles. Type-5 cells were located mainly in the cortico-medullary region and showed the morphological characteristics of undifferentiated elements. Type-6 cells were located exclusively in the medulla and displayed characteristics of cellular activity. Small Hassall's corpuscles consisted of type-6 epithelial cells; in larger corpuscles many nuclei of type-6 cells were found. Cells of types 2 and 6 contained tubular structures (diameter approximately 20 nm).Concerning the function of thymus epithelial cells, the features associated with protein synthesis observed in cellular types 2 and 6 make them likely candidates for humoral factor-producing and/or secreting elements. In addition, type-2 and -3 cells in the cortex appear to contribute to a special pattern of epithelium-lymphocyte interaction (thymic nurse cells), as demonstrated by the intracytoplasmic location of lymphocytes in the epithelial cells. The various steps in intrathymic T-cell maturation occur at locations in a microenvironment composed of morphologically distinct epithelial cells.  相似文献   

19.
Utilization of starch for fat deposition in humans was investigated by means of the nitrogen‐carbon‐balance method in a respiration chamber using the difference principle with a basal and a supplemental period. The basal diet was designed to maintain an adequate energy balance of the volunteer and to meet the maintenance requirements of protein, minerals and vitamins. The dietary fat content was minimized to 2.7% of DM. The digestibility of starch energy was determined to be 97%. The estimated efficiency of ME utilization of starch for energy deposition in humans amounted to 75.8%, which was in accordance with former results in pigs and rats. This suggests that in case of an intake of diets rich in carbohydrates and low in fat the utilization of carbohydrates for lipogenesis in humans is similar to that in monogastric mammal animals.  相似文献   

20.
Summary The morphology of enterochromaffin (EC) cells in the human fundic mucosa was investigated at the lightmicroscopic level by means of the unlabeled peroxidase anti-peroxidase method, with the use of a highly specific anti-serotonin serum.EC-cells in the human fundic mucosa were sparsely distributed below the neck portion of the gland, but were found to be rather numerous in its lower half. Immunohistochemistry revealed marked pleomorphic and seemingly polynuclear EC-cells or cells with long, sometimes multipolar cytoplasmic processes. In addition, luminal contacts and contiguity between EC-cells, or interglandular connections were also encountered.The present immunohistochemical procedure permits, for the first time, a clear-cut morphological visualization of the entire population of EC-cells, and reveals the distinctive morphological features of these cells in the human fundic mucosa. These morphological findings imply that EC-cells in the fundic mucosa may be crucial in gastric function.  相似文献   

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