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1.
Skeletal maturation rates for the age interval 3 to 13 years were analyzed using bone-specific assessments (Greulich-Pyle) of serial radiographs of 40 children. The mean rates of skeletal maturation resembled those of the population from which the atlas standards had been derived. There was a linear trend of skeletal age against chronological age for most bones in each sex. Regression lines were fitted to these data and the b values of the regression lines were calculated. Communality indices were calculated from an intercorrelation matrix of these b values. There was a statistically significant rank order correlation between the sexes in the communality indices. They tended to be higher in the girls than in the boys and were relatively low for the radius, ulna and carpals. Communality indices within groups of bones were high in all rows, especially the metacarpals, but in each sex they were comparatively low in the first ray (metacarpal plus the phalanges of the corresponding digit) and in the fifth ray of the boys. Neighborhood effects on the levels of association of maturation rates were present, particularly in the carpus, but marginal effects were not noted.  相似文献   

2.
Data from serial radiographs of 40 children were used to study the rates of total, diaphyseal and epiphyseal elongation of the bones of the hand from 3–13 years. Communality indices were calculated from complete correlation matrices for each sex. These indices tended to be lower for boys than girls. Communality indices for distal phalanges were lower than for the other bones and those for epiphyseal elongation were lower than those for total or diaphyseal elongation. Correlations between groups of bones in their rates of elongation were higher in rows of bones than in rays. There were statistically significant neighborhood effects and a slight tendency to marginal effects in the correlations between rates of elongation in rows of bones; neither of these effects was present in rays.  相似文献   

3.
Patients with calcaneus fractures experience considerable interferences with daily living activities. The quality of anatomical reconstruction is important because of its influence on functional outcome. The aim of this study was to develop an automatic algorithm based on computer tomographic (CT) images to quantify the integrity of calcaneal joint surfaces. Validation of this algorithm was done by assessing intra-individual variations of characteristic joint parameters. Bilateral hind foot CT data of 12 subjects were manually segmented, and 3D models from the calcaneus, talus and cuboid were generated. These models were implemented in a custom-made software to analyse the area, 3D orientations and bone distance of the joint surfaces of the calcaneus. Three joints were detected, and the calculated parameters were compared between right and left hind foot by the evaluation of the directional asymmetry (%DA). The results were statistically analysed with a paired t-test. The median of area (5–7 %DA) of the joint surfaces and the distance between two articulating surfaces (8–9 %DA) showed the greatest intra-individual differences. Median differences in 3D orientation were comparatively low (1–2 %DA). None of these differences was statistically significant. Inter-individual variations among subjects were several magnitudes larger than intra-individual differences. The presented computational tool provides 3D joint-specific parameters of the calcaneus, which enable to describe their respective joint integrity. The results show that only small intra-individual differences within the anatomy exist. Surgical treatment should take place with the aid of CT data from the contralateral side. Thus, a good restoration of the anatomy may be reached. The computational tool assesses the quality of reduction, and may be helpful to evaluate the outcome and quality of operative treatment based on the calculated joint-specific parameters of joint reconstructions in the hind foot.  相似文献   

4.
Arriving current, width and course of the arteries of the outer nose were investigated at 40 headhalves. We defined 4 groups of vessel patterns. Also 6 types of variations were described and right-left-differences were determined. The results are discussed in detail with the dates of former scientists.  相似文献   

5.
On the origin of the Hirudinea and the demise of the Oligochaeta   总被引:10,自引:0,他引:10  
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.  相似文献   

6.
Melanin deposits in the brain ventricles of Xenopus tadpoles were studied with light and electron microscopy (TEM and SEM). They appeared to be aggregations of melanophages which accumulated free pigment granules excreted by ependymal cells into the cerebrospinal fluid. Whereas the meningeal melanophores contained oval melanosomes of various sizes, the melanosomes in the scavenger cells were all spherical, large (0.6–1.1 μm) and fairly uniform in size. Moreover, they were arranged in spherical groups which were never seen in the cytoplasm of the melanophores. The melanosomes within the cells were identical to the free melanosomes found in the cerebrospinal fluid and those which occurred within the ependymal cells in the young larva, suggesting a common origin from the egg cytoplasm. The number of the melanosomes in the melanophages increased with age. Fine cytoplasmic projections were involved in catching and engulfing the melanosomes. Some other features of the cytoplasm, e.g., large deposits of cell detritus, also indicated that the cells were macrophages. In the later stages, (48, 49) no projections were observed, but the cells were totally filled with melanosomes.  相似文献   

7.
Kinetic parameters of Streptomyces olivocinereus 11-98 growth and biosynthesis of heliomycin were studied. It was shown that carbon sources such as glycerol, mannitol and ramnose were the most favourable for the antibiotic biosynthesis. These carbon sources belonged to the group of substances providing high growth rates of the culture. Ranging of the culture growth rates and antibiotic production levels revealed a set of carbon sources providing a converse relationship between the growth rate and antibiotic biosynthesis i.e. L-arabinose, potassium gluconate, raffinose and sucrose. It was suggested that these compounds were catabolic type regulators of heliomycin biosynthesis.  相似文献   

8.
Alan  Wolfe †  A. M. Long   《Journal of Zoology》1997,242(2):370-375
Irish mountain hare and rabbit hair fibres were examined for differences in microstructure. Obvious and significant differences were found in the widths of the cortex in the shield and shaft regions of the dorsal guard hairs. Other less obvious differences were also noted in scale overlap and patterns. These findings were applied in the examination of a small number of fox scats collected from a coastal grassland habitat. Mammals were by far the most important prey item of the fox; rabbit remains were present in 83% of scats examined. Hare remains were present in 15% of the scats with significantly more hare remains occurring in the scats during winter.  相似文献   

9.
Morphometric electron microscopy data were obtained using a semiautomatic image analysis which demonstrate that the main stages of formation of the external zone of median eminence in the rat hypothalamus take place during the perinatal period. From the 20th day of prenatal period to the 9th day of postnatal period, the length of contact between the neurosecretory axons and the primary portal plexus increases twice, whereas that between the basal processes of ependyma cells and the primary portal plexus by a factor of 1.5. At the same time, the number of secretory granules and microvesicles in axons and that of pinocytotic vesicles in the basal processes markedly increases. Regional differences in the distribution of vesicular structures were noted in neonatal animals: secretory granules were more numerous in the axon swellings remote from the external basal lamina; pinocytotic vesicles were more numerous in the basal processes which terminated in the medial median eminence.  相似文献   

10.
I N Riabov 《Radiobiologiia》1992,32(5):662-667
A study was made of hydrobionts, particularly fishes, living within the thirty-kilometer control zone of Chernobyl NPP and northern part of the Kiev basin, after the disaster. Out of 31 fish species living in the NPP cooling pond some were identified which were mostly affected by radioactive contamination. They were predators belonging, with respect to reproduction and development, to a lithophilous group. Peculiarities of reproduction of Hypophthalmichthys molitrix kept in stews of the cooling pond before the accident were studied. After a three-year exposure to ionizing radiation (cumulative dose of 8-9 Gy) no reduction in the reproductive capacity of mature fishes was observed.  相似文献   

11.
Serial radiographs of the hand-wrist were used to analyze the associations within bones between the rates of change in skeletal maturity, diaphyseal and epiphyseal lengths and diaphyseal width. In previous studies of these children, it has been shown that these rates are linear in relation to chronological age. The associations between the rates of change in these parameters were analyzed using the slopes (b values) for regression lines flitted to the data in each child. In individual bones, most of the correlation coefficients were moderate to low; some were negative. For most associations in each sex they were relatively high for metacarpal II. The rates of skeletal maturation and diaphyseal elongation were correlated more highly in the girls than in the boys but the rates of skeletal maturation and epiphyseal elongation were correlated more highly in the boys. When bones were considered in groups, relatively high correlations were noted for the metacarpals and ray II, lower correlations were common for the middle and distal phalanges. There was no evidence of real neighborhood effects but marginal effects were present.  相似文献   

12.
不同红梨果皮类黄酮合成基因表达模式分析   总被引:1,自引:0,他引:1  
采用半定量和荧光定量PCR方法,分析10个类黄酮合成基因在梨品种‘红星’和‘满天红’成熟果皮中的转录特性以及光照对基因表达的影响.结果表明:‘满天红’花色苷合成上游基因(CHS、CHI)的表达量高于‘红星',而下游基因(F3H、DFR、ANS)以及黄酮醇(FLS)和原花色素(LAR、ANR)合成相关基因的表达量却正好相反.套袋去除光照可使所有被检测基因的转录水平降低,F3GT和FLS最明显,表达量差异达20~30倍以上,且套袋‘红星’中PAL、F3H、DFR、ANS、LAR、ANR基因的表达量仍高于不套袋‘满天红’.研究认为,花色苷合成下游基因转录水平的差异是2个红色梨品种间着色不同的主要原因,而F3GT是光照调控‘红星’着色的关键基因.  相似文献   

13.
Fractions responsible for the main part of the serological and immunogenic activity differing by the set of antigens were isolated from the salt extracts of parapertussis microbes by gel-filtration on Sephadex G-100, ion exchange chromatography on DEAE-cellulose, and preparative electrophoresis in agar. Fractions, disclosing a sufficiently high serological activity and possessing the immunological properties, but containing the minimal set (2--3 out of 7) antigens, which were included in the initial extract, were isolated in the agar gel in the use of the preparative electrophoresis method.  相似文献   

14.
Using the pyroantimoniate technique, a study was conducted at electron microscope level on the distribution of the calcium ion in the pineal glands of normal adult Sprague-Dawley rats with initial weights of 150-200 g subjected to a 12:12 light dark cycle and others under the same conditions were subjected to modifications in the noradrenergic signal, such as continuous illumination over 7 days, blinding by bilateral enucleation (7 or 90 days) before sacrifice and bilateral superior cervical gangliectomy at 21 days before sacrifice. All the animals were sacrificed by decapitation, half of them at midday and the other half at midnight. Abundant fine precipitations of calcium were found in the intercellular spaces of the pineal glands of the normal rats. By contrast, in the gangliectomized animals subjected to constant illumination and chronic binding these precipitations were few in number. Additionally, two types of pinealocytes were observed regarding the distribution and concentration of intracytoplasmic calcium in both the normal and experimentally manipulated animals. Type I correspond to the classic light pinealocytes, with an absence of intracytoplasmic precipitations, although in the normal and gangliectomized animals sacrificed at midnight it was possible to observe fine deposits inside the mitochondrial matrix. Type II correspond to the classic dark pinealocytes, with a dense cytoplasmic matrix and numerous deposits of intracytoplasmic and intranuclear calcium; these were never seen in the type I pinealocytes.  相似文献   

15.
Carbon particles injected into the cortex of the cerebellum of the rat were found in the Virchow-Robin spaces of the adjacent capillaries, and in the adventitia of the cerebellar artery, basilar artery and vertebral artery--both inside and outside the skull. They were also found in some portions of the deeper cervical lymph nodes. However, while tracers injected into the cerebral hemispheres are drained via the tissue channels in the adventitia of the internal carotid arteries, tracers injected into the cerebellar hemispheres are drained via those of the vertebral arteries.  相似文献   

16.
目的:分析经额底纵裂入路治疗鞍上第三脑室底垂体瘤的疗效,探讨其临床适用性。方法:选择从2011年1月~2013年1月与我院行额底纵裂入路手术治疗的30例鞍上第三脑室底垂体瘤的患者,术中行单侧额或双侧额弧形切口,根据术中所见肿瘤位置,由终板、视神经一颈内动脉等存在的生理间隙处切除肿瘤,观察所有患者的手术疗效。结果:所有患者术中可见肿瘤位于鞍内鞍上,部分或全部突入第三脑室底,其中有6例患者伴有脑积水。术中肿瘤全切23例,次全切5例,大部切除2例,无手术死亡病例。术前25例患者视力减退,术后23例患者视力均获得不同程度改善,仅1例暂无明显变化。术后19例出现电解质紊乱,患者经治疗后均已纠正;12例出现不同程度的尿崩症,给予患者药物治疗后,病情得到缓解。术后随访6个月,23例肿瘤全切患者病灶无复发,另外4例次全切者病灶也无明显变化,仅1例次全切和2例大部切除患者于术后行伽马刀再次治疗。结论:经额底纵裂入路治疗鞍上第三脑室底垂体瘤可以达到视野清晰,直观下进行肿瘤切除,手术效果好,并发症较少,适合临床长期推广应用。  相似文献   

17.
By means of morphometric methods, duodenal regional lymph nodes were studied in rhesus and lapunder macaques. It was demonstrated that in monkeys the connective tissue framework, cortical plateau, medullary substance, cortical substance, sinuses and follicles are expressed differently. Cellular elements in the lymph nodes analysed in the monkeys subjected to a comparative investigation demonstrated their uneven distribution in the same structural components. Small lymphocytes were predominate cellular elements. There were rather essential differences in the number of plasmic cells, mitotically dividing cells, acidophilic granulocytes, mast cells and macrophages. Certain species differences were demonstrated to exist both in structure and cell composition of the lymph nodes that seemed to depend on some local peculiarities of immunogenic reactions.  相似文献   

18.
Nine hundred and fourty coagulase-positive and coagulase-negative strains of staphylococci isolated from the skin surface of the mammary glands of 94 pregnant women were tested by the disc agar diffusion method for their sensitivity to five antibiotics. The highest number of the isolates were sensitive to erythromycin and lincomycin (87.7 and 89.7 per cent, respectively). The highest number of moderately resistant strains were detected with respect to methicillin. 19 out of 42 cultures of Staph. aureus were resistant to benzylpenicillin and 24 cultures were resistant to tetracycline. Among staphylococci 130 strains or 13.8 per cent were polyresistant.  相似文献   

19.
Temporal patterns of correlated firings were studied in small groups of neurons simultaneously recorded in the frontal cortex of a behaving dog. To identify the character of relations between the patterns of interneuronal connections in local ensembles and event-related potentials (ERP), the following procedure was applied. At the first step, single trials of behavioral task were classified by clustering temporal distribution of correlated firings in pairs of units. Then the surface ERP were averaged separately for each cluster and parameters of the ERP components were compared between the clusters. The analysis revealed 3 of 7 recording sites, where significant differences were observed between the ERP sampled from the clusters with different structures of the local interneuronal connections. The results suggest that temporal modulation of interactions between neurons in local ensembles reflects a large-scale reorganization of cortical networks.  相似文献   

20.
For the first time, the study of the mycobiota of littoral sands of the cold-water White Sea was conducted. Twenty-four samples were collected in July–August 2015 in the Onega Bay, the Kandalaksha Bay, and on the Terskii coast. Culture methods were used to detect the number of colony forming units (CFU) and the fungi diversity. The number of CFUs is small; it ranges from 0 to 57 per 1 cm3. A total of 54 morphotypes were detected, of which 22 were identified to the species, seven to the genus level, and 25 were not identified, because they did not form sporulation. Only two species, Cladosorium sphaerospermum and Paradendryphiella salina, were characterized by the relative abundance of more than 10% and the frequency of occurrence of more than 50%. Another five species were found in more than one sample: Penicillium chrysogenum, Cadophora fastigiata, Acremonium fuci, anamorph of Pseudogymnoascus pannorum, and teleomorph of Pseudeurotium hygrophilum. All other morphotypes were found in a small number in single samples. In general, darkcolored forms predominated in the mycobiota both in diversity and in number.  相似文献   

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