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We document histological changes through ontogeny in the epiphyseal cartilage of the third phalanx of Rana caralitana from Turkey and provide an assessment of the maturation of the epiphysis from newly metamorphosed froglets to 10‐year‐old individuals. The epiphysis of R. caralitana is compared to other Rana taxa previously studied, and we report on novel histological data pertaining to later stages of epiphyseal growth in this taxon. In addition, we document the development of endochondral ossification in late stages of ontogeny in R. caralitana. Our results suggest a correlation between the long lifespan of R. caralitana and the developmental changes and maturation of the epiphyseal cartilage in this taxon. This study also provides a quantitative assessment of the different regions of the epiphyseal cartilage in the epiphysis of Rana through ontogeny, and has therefore permitted quantifiable deductions about the relative maturation and differentiation of the chondrocytes of the epiphysis through time. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

3.
In this study, we used the skeletochronology method to estimate various growth parameters, such as age structure, minimum and maximum life span, age of sexual maturity, and the relationship between body size and weight of eight different populations of the variable toad, Bufotes viridis sitibundus, in Turkey. Further, we determined the relationship between these parameters and ecologic factors using the partial Mantel test. A significant difference was found among the populations with respect to age, body size, and body weight in both males and females. On average, the maximum life span was recorded as 10 years for males and 11 years for females. In the studied populations, the average age of sexual maturity ranged between 2 and 4 years for both sexes. Sexual dimorphism in terms of snout-vent length (SVL) was not observed between males and females in all the populations. Toads from the higher altitudes tended to be significantly larger, older, and heavier than those from lower altitudes. We concluded that altitude and temperature have an impact on the growth rate, body size, and body mass.  相似文献   

4.
Karyotypes of the Tago brown frog Rana tagoi and stream Tago brown frog Rana sakuraii from a mountain region in the Nishitama district in Tokyo were examined by conventional Giemsa staining, C-banding and late replication (LR)-banding. Chromosome number was 2n = 26 in all cases. The 26 chromosomes consisted of five (1–5) pairs of large chromosomes and eight (6–13) pairs of small chromosomes. Chromosome 10 had a secondary constriction on the long arm. In all frogs, on chromosome pair 8, the XX/XY type sex chromosome was present. C-banding analysis indicated that, in R. sakuraii, neither the X nor Y chromosome possessed interstitial C-bands but each had centromere staining, while in R. tagoi, an interstitial C-band was present on the long arm of the X chromosome. The Y chromosome had no interstitial C-band. LR-banding analysis demonstrated the X and Y chromosomes to have a LR-band on the short arm and two LR-bands, each on the long arm, and the bands on both species to be essentially the same. Heteromorphic sex chromosomes in males of R. sakuraii and R. tagoi were identified for the first time in this study. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
Electron microscopy of the lungs of Melanophryniscus stelzneri stelzneri (Anura) revealed the presence of a complex pattern of corpuscular cells (CCs). The respiratory surface over the septa presents small areas where the CCs are grouped forming neuroepithelial bodies (NEBs). These corpuscular structures can also be localized in the inner layer of the lung wall. Although in both cases NEBs protrude slightly into the airway lumen, they are separated from the airway lumen and the basal connective tissue by thin apical and basal cytoplasmic processes of neighbouring pneumocytes. Ultrastructurally, the CCs possess a large nucleus, clear cytoplasm and vesicles of variable morphology and size, containing an electron dense material surrounded by a lucent space in some cases. The size of these dense-core vesicles (DCVs) ranged from 40 to 100 nm. The NEBs are associated with afferent and efferent terminal nerves. These types of nerve endings are located between the CCs and in the basal part of the NEBs. The location of the NEBs in strategic positions on the septa and in the wall of the lung, the presence of the DCVs in the basolateral region of the CCs, the occurrence of synaptic contacts between nerve endings and the CCs and the occurrence of capillaries close to the NEBs, suggest a receptosecretory function for NEBs in the lung of M.s. stelzneri.  相似文献   

6.
Osteohistology, the study of bone microstructure, provides an important avenue for assessing extinct and extant vertebrate growth and life history. Cortical vascularity and collagen fibre organization are direct reflections of growth rate, while bone growth marks are indicative of absolute age. However, each skeletal element has its own ontogenetic trajectory and microstructure of certain bones may not be a true representation of whole body growth. Extensive comparative study of modern taxa is required to resolve intraskeletal discrepancies among age, vascularity and tissue organization in extinct vertebrates. Despite their comparative utility, studies of bone microstructure in modern taxa are severely lacking. Here, we add to a growing comparative osteohistological database by describing (1) bone tissue organization, (2) growth mark count, (3) sexually dimorphic bone (e.g. medullary bone) and (4) secondary cortical reconstruction in the bone microstructure of a 14-year-old male and 5-year-old female North Island Brown Kiwi (Apteryx mantelli). Transverse and longitudinal histological ground sections were processed and described for femora, tibiotarsi, tarsometatarsi, humeri, ulnae and radii in both kiwis. Cortical bone can generally be described as parallel-fibered tissue, interrupted by cyclical growth marks, with vascular canals oriented longitudinally within primary and secondary osteons. Tissue morphologically resembling medullary bone is present in the hindlimbs of the female, and coarse compacted cancellous bone (CCCB) is found sporadically in the male and female hindlimbs. Lines of arrested growth (LAGs) are present in all hindlimb bones of both kiwi, but remodelling has obliterated all LAGs in the male ulnae and radii. LAG count varies intraskeletally, but large weight bearing elements such as femora and tibiotarsi have less remodelling and, thus, higher number of LAGs. LAG count did not match absolute age in any skeletal element; a maximum of seven LAGs are present in the male kiwi and a maximum of seven LAGs in the female kiwi. The tissue organization within the forelimbs and hindlimbs is reflective of the protracted growth strategy of the North Island Brown Kiwi and congruent with previous studies of the kiwi. LAGs were highly variable throughout the skeleton of the kiwi and a decoupling of age and LAG deposition is apparent from the male kiwi samples. Excess LAGs in the 5-year-old female kiwi may be a product of hatching, egg laying or captivity. Regardless, LAG count variation in the kiwi stresses the importance of intraskeletal sampling when assessing growth patterns of extinct taxa. An extensive ontogenetic sampling of kiwi is necessary for future investigations of bone growth patterns, CCCB formation, medullary bone and LAG deposition and obliteration in these elusive birds.  相似文献   

7.
Gnathostomatid nematodes identified morphologically as Spiroxys japonica Morishita, 1926 were collected from the dark-spotted frog Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae) in China. Light and scanning electron microscopy were used to study the morphology of this species in detail. Previously unreported morphological features are revealed and others corrected. In addition, adult nematodes of S. japonica collected from P. nigromaculatus and Spiroxys hanzaki Hasegawa, Miyata & Doi, 1998 collected from Andrias japonicus (Temminck) (Caudata: Cryptobranchidae) in China and Japan, respectively, and the third-stage larva of S. japonica collected from Lithobates catesbeianus (Shaw) (Anura: Ranidae) in Japan, were characterised using molecular methods by sequencing and analysing ribosomal [large ribosomal DNA (18S) and internal transcribed space] and mitochondrial [cytochrome c oxidase subunit 1] target regions, respectively. The new morphological and genetic data contributes to a more accurate diagnosis of this hitherto little known nematode genus.  相似文献   

8.
Water frogs, Pelophylax perezi, that are introduced in the Azores, were screened for parasites using PCR primers known to amplify Apicomplexa parasites, and using nematode-specific primers. With the former, three different organisms were detected: Hepatozoon, a trichodinid protozoan ciliate and a possible Stramenopile. Using the latter set of primers, a single unknown spirurid nematode was also detected. Phylogenetic analyses indicate that Hepatozoon detected within amphibian hosts appear to form a clade, although relationships of these parasites do not match the vertebrate intermediate host phylogeny. Regarding the possible Stramenopile, it is unclear whether this organism was actually present on the amphibian or in the water on the surface of the tissue sample. Our findings highlight that many different organisms can be detected with these primers and that they can be used to screen introduced host populations to detect parasites that have been brought with them.  相似文献   

9.
The nucleolus organizer regions (NORs) of both karyotypes I and II of Physalaemus petersi (Jiménez de la Espada, 1872) from the Brazilian Amazon were studied by Giemsa staining, and by the Ag- NOR method. Karyological group I specimens were also studied by the fluorescence in situ hybridization (FISH) technique. Multiple NOR-bearing chromosomes were detected in both karyotypes. The coincident results of the Ag-NOR and FISH methods rule out the occurrence of silent NORs in this anuran. There was no intraindividual NOR variability in either group, but interindividual variability of NORs was high in group I. Seven different patterns of active NOR distribution were definitely recognized among fifteen specimens. This was considered to be a NOR site polymorphism. These results, combined with the C-band polymorphism previously reported for P. petersi, demonstrate a high rate of chromosome evolution in this group.  相似文献   

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董静娟  董辉 《医学信息》2019,(3):131-133
目的 通过对邯郸地区生长发育异常(矮身高)儿童骨龄评价,探索该组儿童的生长发育现状,从而指导临床对生长发育异常儿童的重视和关注,达到早发现、早干预、早治疗等目的。方法 收集邯郸地区2014年1月~2017年12月以生长发育异常(矮身高)而就诊,拍摄手腕部骨龄片1478例,应用CHN骨龄测评方法和G-P图谱法对其骨龄进行评估,根据骨龄判定标准,从而判定矮身高儿童的骨龄现状。结果 ①矮身高儿童的骨龄表现骨龄落后657例,骨龄吻合578例,骨龄提前243例,以骨龄落后为主,男性小于生活年龄(1.38±1.39)岁,女性小于生活年龄(1.25±0.76)岁。②不同原因导致的矮身高骨龄生长学特征不同;③手腕骨不同骨骺,在骨龄落后的程度也不同,在657例骨龄落后病例中,尺骨发育晚或形态落后130例,腕骨数量少或形态落后178例,多个骨骺联合发育落后125例,伴有第二掌骨基底部假骨骺77例,而桡骨远端、掌指骨骨骺发育晚的所占比例较少。结论 ①矮身高儿童的骨龄发育可以表现为骨龄落后、骨龄提前和骨龄吻合,以骨龄落后为主;②不同病因导致的矮身高骨龄生长学特征不同,不健康生活方式、先天条件不足、特发性矮小导致的矮身高,骨龄多落后在2岁以内多见,而病理性矮身高,如生长激素缺乏大部分骨龄落后,多在2岁左右,甲状腺功能低下导致的骨龄落后程度较大,一般在3岁左右,肾脏疾病导致的骨龄情况髓这体内激素分泌的变化而变化,可骨龄落后、也可骨龄提前;而Turner综合征及其他基因遗传性疾病中,骨龄落后程度较小,多在1~2岁;性早熟导致的矮身高,骨龄多提前,偶有骨龄落后的发生。③骨龄落后以腕骨、尺骨出现晚或形态落后、或多个骨骺联合落后为主,但伴有第二掌骨基底部假骨骺也有一定比率,是否能作为判定骨龄落后的标志有待研究。  相似文献   

12.
Three types of serous products were detected in the syncytial cutaneous glands of the leptodactylid tungara frog, Engystomops pustulosus: type Ia, granules with wide halos and variable density cores; type Ib, high density granules without halos; and type II, vesicles containing a finely dispersed product. Ultrastructural evidence revealed that these products were manufactured by different serous gland types and excluded that they represented different steps in the secretory cycle of a single gland type. Indeed, secretory maturation affecting the products released by the Golgi apparatus proceeded through different mechanisms: confluence (vesicles), interactions between syncytium and secretory product (type Ib granules), and a combination of both processes (type Ia granules). In conclusion, this investigation of secretory maturation was shown to be a suitable approach for the identification of serous gland polymorphism and demonstrated that the tungara frog belongs to the minority of anuran species characterized by this peculiar morpho‐functional trait. Anat Rec, 298:1659–1667, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

13.
The determination of age is an important step in defining the life history traits of individuals and populations. Age determination of odontocetes is mainly based on counting annual growth layer groups in the teeth. However, this useful method is always invasive, requiring the cutting of at least one tooth, and sometimes the results are difficult to interpret. Based on the concept that bone matrix is constantly deposited throughout life, we analysed the bone mineral density of the arm and forearm of a series of bottlenose dolphins (Tursiops truncatus, Montagu 1821) stranded along the Italian coast of the Adriatic Sea or maintained in confined waters. The bone mineral density values we obtained were evaluated as possible age predictors of the Mediterranean population of this species, considering age as determined by counting growth layer groups in sections of the teeth and the total body length of the animal as references. Comparisons between left and right flipper showed no difference. Our results show that bone mineral density values of the thoracic limb are indeed reliable age predictors in Tursiops truncatus. Further investigations in additional odontocete species are necessary to provide strong evidence of the reliability of bone mineral density as an indicator of growth and chronological wear and tear in toothed-whales.  相似文献   

14.
Summary The structural organization of the kidney ofTyphlonectes compressicaudus (Amphibia, Gymnophiona) was studied by light microscopic (LM) examination of serial paraffin and semithin Epon sections. The kidney is slender and quite long and has a mesonephric segmental construction; the excretory duct (Wolffian duct), running along the lateral side of the kidney, segmentally receives the terminal trunks of the collecting duct system. The nephron has the following parts: renal corpuscle, neck segment, proximal tubule, intermediate segment, distal tubule and connecting tubule. The distal tubule is located in a ventromedial (central) zone of the kidney; all other tubular segments lie in a dorsolateral (peripheral) zone. The renal corpuscles are found at the border between these two zones.The renal corpuscle is very large; its urinary pole faces the peripheral zone. A small proportion of neck segments receive either a nephrostomal duct or a blind branch. The proximal tubule is a thick, highly convoluted tubule. The intermediate segment is ciliated and makes a few coils. The distal tubule is composed of three portions: a highly convoluted part in the central zone, subsequently an attachment site with the renal corpuscle and a short postattachment-part. The connecting tubule and the collecting duct have a heterogeneous epithelium consisting of light and dark cells. The collecting duct is distinguished by dilated intercellular spaces. The Wolffian duct has a pseudostratified epithelium.The present study correlates the course and segmentation of the renal tubule ofTyphlonectes. The tubule has three major convolutions. The first occurs in the proximal tubule in the peripheral zone; the second is established by the distal tubule and occurs in the central zone; the third is formed by the connecting tubule and is found in the peripheral zone.Research fellow of the Alexander von Humboldt foundation: home address: Department of Anatomy, Faculty of Medicine, University of Tokyo, Tokyo 113, Japan  相似文献   

15.
An ultrastructural study was carried out on the epidermis of Agalychnis callidryas tadpoles during limb development. Larval epidermis consisted of four cell layers: basal, lower intermediate, upper intermediate, and surface or apical layers. Basal cells represented the stem compartment of intermediate cells: both belong to the skein cell (SC) lineage, described in several anuran species, on account of the conspicuous intracytoplasmic tonofilament bundles. Apical cells were secretory in nature and released mucus on the body surface. Intermediate SCs exhibited a hydrated central cytoplasm and peripheral tonofilament bundles. They closely resembled the epidermal ball‐like cells, Kugelzellen (KZn) of Xenopus laevis tadpoles, and possibly shared their turgor‐stiffness properties. In A. callidryas, the stratification of intermediated SCs on their stem cell layer provided the chance to study their cytodifferentiation in a suitable sequence, until basal cell differentiation shifted toward the keratinocyte lineage in premetamorphic stages. Present data assign A. callidryas to the anuran species with a constitutive SC population in larval epidermis, and demonstrate that KZn express the ultimate specialization of such cell line. SCs were arranged in the fashion of a random‐rubble stone groundwork, and possessed long processes. These cytoplasmic outgrowths contained a tonofilament axial rod and held together contiguous cells. Ultrastructural findings suggest that this complex structure may impart compressive as well as sliding strengths to the larval epidermis, representing a possible adaption to the fresh water environment. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

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The neuropeptide FF (NPFF) is a member of the RFamide related peptides (FaRPs) that share the dipeptide Arg-Phe-NH2 at their C-terminal. It was originally isolated from bovine brain and its wide distribution has been demonstrated in the brain of several mammalian species. By means of an NPFF antiserum we have investigated the distribution pattern of NPFF-like immunoreactive cells and fibers in the brain of anuran and urodele amphibians. In both amphibian orders, the most conspicuous labeled cell population was found in the preoptic area and hypothalamus, primarily in the suprachiasmatic region. Numerous fibers reached the median eminence and the intermediate lobe of the hypophysis. Only in the anuran brain cells were observed in the pallium and septum. In the urodele, cells and fibers of the terminal nerve were distinctly labeled. Cell bodies were widely distributed in the reticular formation of anurans and, in both orders, a large cell population was found in the nucleus of the solitary tract and the spinal cord. Comparable fiber distribution between both orders exists in which the basal telencephalon (mainly the amygdaloid complex), the hypothalamus and the spinal cord are the regions most richly innervated. The distribution pattern of NPFF-like immunorective elements in the brain of amphibians, which only partly overlaps with those of other FaRPs, supports the notion that a NPFF-like peptide exists in amphibians. On the basis of its localization, this peptide may act as a hypophysiotropic neurohormone and be involved in background adaptation. Its wide distribution in similar zones of the brain in amphibians and mammals suggests that functional roles of this peptide have been conserved in vertebrate evolution.  相似文献   

18.

Purpose

The serum concentrations of insulin-like growth factors-I (IGF-I), insulin-like growth factor binding protein-3 (IGFBP-3) and growth hormone (GH) are related to body composition, function and metabolism, and are influenced by the aging process. This study was to investigate the influence of gender on serum concentrations of IGF-I, IGFBP-3 and GH in middle and old age subjects.

Materials and Methods

Sixty healthy volunteers (male 35, female 25, 36-70 years) were divided into ≤ 50 and > 50 years groups, based on gender. Women > 50 years were post-menopause. IGF-I, IGFBP-3, and GH were determined by immunoradiometric assay.

Results

IGF-I was shown to be negatively correlated with age (women r = -0.62, p < 0.001; men r = -0.38, p < 0.05), whereas there was no correlation between IGF-I and GH values. Women > 50 years showed a significant reduction in IGF-I values than women ≤ 50 years (p < 0.01). Women > 50 years showed smaller IGF-I/IGFBP-3 molar ratios (0.177998 ± 0.039404) than men of same age group (0.228326 ± 0.050979, p < 0.01) and women ≤ 50 years (0.247667 ± 0.069411, p < 0.01). Age was shown to positively correlate with GH/IGF-I (r = 0.49, p < 0.05) and GH/IGFBP-3 ratios (r = 0.40, p < 0.05) in women.

Conclusions

The influence of aging on serum concentrations of IGF-I is more remarkable in women than in men. Menopause causes reduction of IGF-I/IGFBP-3 molar ratio. Women have the trend of progressive hypoactivity of GH to stimulate IGF-I and IGFBP-3 secretions with age.  相似文献   

19.
目的:检测宫内发育迟缓(IUGR)儿脐血胰岛素样生长因子-I(IGF-I)、胰岛素样生长因子结合蛋白-3(IGFBP-3)水平,分析这些指标的变化程度与胎儿期生长的关系。方法:将86例脐血标本分为IUGR(即小于胎龄儿)组和适于胎龄儿(AGA)组。采用放射免疫分析(RIA)测定IGF-I水平,免疫放射分析(IR-MA)测定IGFBP-3水平。两组间比较用t检验,两变量之间的关系采用相关回归分析。结果:与AGA组相比,IUGR组脐血IGF-I和IGFBP-3水平显著降低(P均〈0.01);IGF-I、IGFBP-3均随胎龄及出生体重增加而增加(P均〈0.01);IGFBP-3与IGF-I呈正相关(P〈0.01)。结论:脐血IGF-I和IGFBP-3的含量可作为判断新生儿生长发育程度的一项客观指标。  相似文献   

20.
Ectothermic vertebrates have a well‐developed system of melanin‐containing cells, which localize in several organs and tissues and compose an extracutaneous pigmentary system. This research aimed at characterizing histological and ultrastructural patterns of pigmented cells in the testes of the anura Eupemphix nattereri (Steindachner, 1963), including the stereological and quantitative evaluation of this cell type in the gonads. Ten adult males were collected in Nova Itapirema, São Paulo, Brazil, and submitted to morphological studies with light and transmission electron microscopy. The testis presents a great number of large cells with many brown granules and long cytoplasmic processes. The pigmented cells found in the testis are structurally similar to melanocytes, characterized by large amounts of melanosomes. The cells may be in intimate contact with the same cell type, with myoid cells surrounded by a large amount of collagen fibers, Leydig cells, and next to fibroblasts. The distribution and amount of extracutaneous melanocytes is variable when other organs and membranes are analyzed, allowing the establishment of species‐specific patterns for the extracutaneous pigmentary system. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

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