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1.
A bright yellow-green specific fluorescence is induced by formaldehyde histochemistry for monoamines in the secretory nerve trunks of the Octopus vulgaris posterior salivary duct, and in their ramification in the gland tubules. In contrast, the motor nerve trunks of the duct contain few fluorescent elements. The muscular and connective coat of the duct is provided with fluorescent globular and varicose structures, of various sizes and colours, which become numerous in the duct branches. At least some of these peripheral structures belong to varicose monoamine nerve fibres. In the gland, on the contrary, the muscle cells surrounding the tubules are not supplied with fluorescent nerve fibres.  相似文献   

2.
蜣螂与壁虎刚毛的比较及改形对其功能的影响   总被引:11,自引:0,他引:11  
脱附与粘附是工程作业的两个相互矛盾的难题,土壤和物料的粘附严重降低了机械的作业效率和质量,没有粘附又使某些机械无法工作或运行。目前世界流行的脱附技术,包括向界面注入空气的充气法、向界面注入溶液的充液法、利用机械或超声波的振动法、施加电场的电渗法、施加磁场的磁  相似文献   

3.
The histological host response of female CF-1 mice to Hymenolepis microstoma involves dramatic changes in the host's bile duct and liver. These changes are similar to those described by previous investigators using different strains of mice. The histological changes which occur in bile duct and liver tissues of female CF-1 mice are accompanied by a significant hypertrophy of these organs; the wet weights of the bile duct and liver increase almost 2000 and 50%, respectively, in infected mice. No significant histopathological changes are found in the spleen or small intestine tissues of infected mice, yet the wet weight of both of these organs increases almost 100%. The magnitude of the histopathological changes which occur in the bile duct could possibly account for the increase in wet weight, i.e., there is significant fibrosis, but the histological changes in the liver, spleen, and small intestine do not appear to be of sufficient magnitude to account for the increases in wet weight.  相似文献   

4.
Background  Vestigial remnants of the mesonephric duct and paramesonephric duct are well-known developmental abnormalities of the human testis and epididymis.
Methods and results  During routine macroscopic and histological examination of four cynomolgus macaques, three different forms of testicular and epididymal appendages were observed, namely a unilateral appendix testis, a bilateral appendix epididymidis, and several vasa aberrantia. By histological and immunohistochemical examinations it could be demonstrated that both the appendix testis and the appendix epididymidis consisted of a central fibromuscular core and a pseudostratified columnar epithelium at the outer surface. The vasa aberrantia were attached to the connective tissue sheaths of the epididymis/testis and were represented by small duct-like or cystic structures internally lined with a simple cuboidal to columnar, partly ciliated epithelium.
Conclusion  Awareness of these rudimental tissues in non-human primates is necessary to determine actual incidence rates in non-human primate species used in toxicological research and avoids misdiagnosing during routine necropsy and histological examinations.  相似文献   

5.
利用生物显微技术观察和研究了四川短尾鼩(Anourosorex squamipes)唾液腺的组织结构。结果表明,腮腺属纯浆液腺,有闰管和分泌管,无颗粒曲管;颌下腺属混合腺,以混合性腺泡为主,有少量浆液性腺泡和黏液性腺泡,有闰管、颗粒曲管和分泌管;舌下腺属纯黏液腺,有闰管和分泌管,无颗粒曲管,但在分泌管上存在有颗粒曲管细胞。  相似文献   

6.
Sex identification in young sea turtles is challenging. Sea turtle neonates lack external dimorphic characteristics and heteromorphic sex chromosomes. We compared the morphology of the gonads and reproductive ducts of dead formalin-preserved hatchling and post-hatchling Caretta caretta, Dermochelys coriacea, and Chelonia mydas and identified sex-specific differences in these structures that are useful in assigning sex. We tested 11 gross gonadal and reproductive duct characteristics in 57 neonate sea turtles and verified the sex by histological examination. A suite of four characters was found to reliably indicate sex in the three species considered: paramesonephric duct size, mobility of the duct, presence of a complete lumen and gonad mobility. Additionally, gonad shape and edge form were dependable sex-specific characters in cheloniids but not in D. coriacea. Together, these morphological characteristics provide new and reliable methods to quickly distinguish sex in preserved neonate sea turtles without using more extensive histological methods.  相似文献   

7.
It is unknown why some patients with inflammatory bowel disease develop primary sclerosing cholangitis. We have recently shown that patients with primary sclerosing cholangitis have an increased prevalence of mutations in the gene responsible for cystic fibrosis (CFTR) compared with individuals with inflammatory bowel disease alone. Our aim was to examine whether induction of colitis by oral dextran leads to bile duct injury in mice heterozygous or homozygous for mutations in CFTR. The effect of oral administration of docosahexaenoic acid to correct a fatty acid imbalance associated with cystic fibrosis was also examined to determine whether this would prevent bile duct inflammation. Wild-type mice and mice heterozygous and homozygous for CFTR mutations were given dextran orally for 14 days to induce colitis. Bile duct injury was quantitated by blinded histological scoring and measurement of serum alkaline phosphatase activity. The effect of pretreatment with docosahexaenoic acid for 7 days was examined. Treatment of mice with 100 mg dextran/day for 9 days followed by 85 mg/day for 5 days resulted in a significant increase in bile duct injury as determined by histological scoring in homozygous cystic fibrosis mice compared with wild-type mice (P = 0.005). The bile duct injury seen in cystic fibrosis mice was reflected in a threefold increase in serum alkaline phosphatase (P = 0.0006). Pretreatment with oral docosahexaenoic acid decreased both histological evidence of bile duct injury and serum alkaline phosphatase levels. In the setting of colitis, loss of CFTR function leads to bile duct injury.  相似文献   

8.
The present study was carried out to determine the detailed histological and cytological features of the excurrent ducts of the male reproductive system in the rhesus monkey. The excurrent ducts show a regional difference in their histological features. The use of some of these features as histological markers and their possible functional significance are discussed. The epithelial cells in the different components of the excurrent duct system possess cytological features which suggest their involvement in absorption and the secretion of different products into the lumen.  相似文献   

9.
The morphology, blood and nerve supply of the parotid salivary glands of the one-humped camel were studied in detail. The intraglandular portion of the duct system was also examined. The histological and histochemical studies showed that the parotid salivary glands of the camel are of the tubuloacinar type and are serumocoid in nature. The secretory acini and tubules show themselves in 3 different forms according to the different phases of their secretory cycle. The duct system of the gland contains goblet cells between its lining epithelium. The intercalated ducts show ampullation followed by narrowing that help in mixing the secretion. Intraepithelial glands are found in the terminal part of the parotid duct.  相似文献   

10.
T Yamane  K Mori  K Sakamoto  S Ikei  M Akagi 《Acta anatomica》1988,133(2):162-172
We defined the subsegmental divisions and the ramification patterns of the portal vein in the right and caudate lobes using 25 human liver casts. The ramifications of the portal vein and the subdivisions of the liver were classified based on the major portal veins with the largest diameter and those having a diameter of not less than two thirds of the largest vein in each subsegment. The following results were obtained. (1) The portal trunk showed three ramification patterns and the basic pattern was bifurcation (80%). (2) The anterior portal vein first ramified into several anterior-inferior portal veins (P5) and ran toward the superior direction to bifurcate into 2 major portal veins in the anterior-superior subsegment (S8). (3) There were three types of ramification patterns of the portal veins in S8: bifurcation (84%), trifurcation and one-pedicle type. (4) There were also three branching types of the largest vein (P5-max) in P5: ramification from the anterior portal vein, P8-anterior vein supplying the anterior region of S8 and P8-posterior vein supplying the posterior region of S8. (5) The posterior portal vein showed two ramification patterns of the bifurcation (36%) and nonbifurcation type. (6) The major portal veins in the caudate subsegment ramified at various sites such as the portal trunk, left, right and/or other portal veins.  相似文献   

11.
In the coral reef fish Thalassoma bifasciatum , males vary the number of sperm they release in successive spawnings with individual females in accordance with female body and clutch size. The morphology and histological structure of the male genital papilla, sperm duct, oviduct and surrounding musculature were examined in an effort to elucidate the mechanism permitting control of the number of gametes released during mating. In males, urinary and genital ducts pass separately through a common urogenital papilla and are associated with a striated sphincter muscle and a pair of thin, smooth ligament muscles arising from the first proximal anal fin radial and passing laterally around the sperm duct and oviduct. Within the papilla, the sperm duct resembles a narrow funnel whose inner walls contain longitudinal folds or septa protruding into the lumen of the duct. Dorsal to the papilla, the sperm duct enlarges and is divided into numerous, open chambers by irregular, longitudinal trabeculae. The wall of the duct and the trabeculae contain flat epithelium, smooth muscle and loose connective tissue. In females, the oviduct contains no trabeculae and is not divided into chambers. The ligament muscles are more thoroughly embedded in the sphincter muscle of the rectum than in males. Some ways in which these structures might control gamete release are suggested.  相似文献   

12.
We describe the histological characteristics of the testis and spermatogenesis of the cave molly Poecilia mexicana, a viviparous teleost inhabiting a sulfur spring cave, Cueva del Azufre, in Tabasco, Southern Mexico. P. mexicana has elongate spermatogonial restricted testes with spermatogonia arranged in the testicular periphery. Germ cell development occurs within spermatocysts. As spermatogenesis proceeds, the spermatocysts move longitudinally from the periphery of the testis to the efferent duct system, where mature spermatozoa are released. The efferent duct system consists of short efferent duct branches connected to a main efferent duct, opened into the genital pore. Spermatogenesis consisted of the following stages: spermatogonia (A and B), spermatocytes (primary and secondary), spermatids, and spermatozoa. The spermatozoa are situated within spermatocysts, with their heads oriented toward the periphery and flagella toward the center. Once in the efferent duct system, mature spermatozoa are packaged as unencapsulated sperm bundles, that is, spermatozeugmata. We suggest that the histological characteristics of the testis and spermatogenesis of P. mexicana from the Cueva del Azufre, and the viviparous condition where the spermatozoa enter in the female without been in the water, have allowed them to invade sulfurous and/or subterranean environments in Southern Mexico, without requiring complex morphofunctional changes in the testis or the spermatogenetic process.  相似文献   

13.
Bile ducts were examined histochemically to compare the effects of proline infusion with Fasciola hepatica implantation in rats. After 3 weeks of infusion or implantation, both proline and F. hepatica produced increases in the luminal perimeter and collagen content of the bile duct. However, the effect of the parasite was significantly greater than that of proline, and the parasite produced significant increases in the bile duct wall. These results corroborate earlier biochemical and histological studies indicating the important role of proline in the enlargement of the bile duct in fascioliasis.  相似文献   

14.
Male preputial and female clitoral glands of mice undergo development that depends on the level of hormones in the animal. Experimental infection with Taenia crassiceps cysticerci results in significant physiological modifications in the host. Here, we investigated the histomorphological alterations induced by the parasite in these pheromonal glands. Preputial and clitoral glands were recovered from mice at 15, 35, 50, and 70 days postinfection (DPI). The glands were examined macroscopically and microscopically after histological preparation. Male preputial glands show a marked atrophy 35 days after infection. This atrophy is the result of a disorganization of the acinus tissue structure. During the course of infection, the basal, intermediate, and mature acinar cell layers are reduced, and finally, at 70 DPI, the gland includes only the duct system and fibrotic structures. In contrast, females are not affected by the infection because no modifications were observed in the morphology or histology of the clitoral glands. A probable cause for such a divergence between infected male and female mice might be related to a sex steroid imbalance as described during T. crassiceps infection.  相似文献   

15.
Bile acids in the rat: studies in experimental occlusion of the bile duct   总被引:2,自引:0,他引:2  
Bile acids in the plasma, urine, and small intestine of adult male rats with occluded bile ducts have been studied using a method of high specificity for their determination. After bile duct ligation cholic acid rapidly accumulates in the plasma for 8 hr, remains high for a further 8 hr, and subsequently diminishes; bile acids disappear from the small intestine. During the first 12 hr after bile duct ligation the excretion of trihydroxy acids in the urine was 10 times that of the dihydroxy acids. Subsequently the two excretion rates became equal. Because bile acids have been implicated in the etiology of hepatic damage following bile duct ligation, studies have been made of the effect on the liver of removing (with cholestyramine) and supplementing (with cholic acid) the intestinal bile acid pool. The addition of cholestyramine to the stock diet prevented the rise in trihydroxy bile acids after bile duct ligation, but did not prevent the development of histological abnormalities in the liver. Supplementing the diet with cholic acid raised the plasma cholic acid levels but had little effect on the hepatic histological findings.  相似文献   

16.
Morphogenic effects of ramihyphin A in filamentous fungi   总被引:2,自引:1,他引:1  
Ramihyphin A at subfungistatio concentrations stimulates ramification of hyphae of filamentous fungi. Stimulation of terminal ramification of hyphae that can be observed particularly in phytopathogenic fungi is most frequent. Hyphae ofMicrosporon canis, Trichophyton mentagrophytes, Blastomyces dermatitidis, Coccidioides immitis andHistoplasma capsulatum ramify intensively laterally. Stimulation of the lateral ramification was observed inMonilia fructigena, Penicillium marneffei andPenicillium chrysogenum. The antibiotic induces also formation of vesicular structures in phytopathogens. Due to the substantial ramification of hyphae, both terminal and lateral, the growth of colonies is interrupted. The addition of the antibiotic to a growing colony ofBotrytis cinerea induces dichotomic ramification of terminal hyphae after 3 h of growth. Lateral hyphae begin to grow later and further ramify dichotomically. Dense bundles of ramified hyphae are formed after 24 h due to the unbalanced ramification and the colony no longer increases its size.  相似文献   

17.
Liang G  Liu QQ  Yu HH  Wang QX 《动物学研究》2011,32(6):663-669
To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological techniques. Also, the correlation of androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR) and aromatase (Ar) expressions in the vas deferens and testis were studied immunohistochemically. To confirm that the sperm and the spherical structure existed in deferens ducts, we also used routine histological technique observed deferens ducts in the Striped-tailed rat-snake (Elaphe taeniura), Red-banded snake (Dinodon rufozonatum), and Tiger-spotted neck-troughed snake (Rhabdophis tigrina lateralis). The results showed that the deferens ducts of the Chinese Rat Snake were composed of efferent duct, epididymal duct and vas deferens. Efferent duct contained sperm from August-October, and the sperm were observed in the epididymal duct from August-the following January. Throughout the year (except July) a large number of sperm were present in the vas deferens where a previously unreported spherical structure formed by spermatids was observed, which showed no significant differences in the IOD values of AR-, ER-, PR- and Ar-immunoreactivities. Since the spermatids in the spherical structure were undergoing spermatogenesis and this phenomenon also existed in the Striped-tailed rat-snake and Red-banded snake, the term, seminiferous spherule, was named for this spherical structure This study demonstrated that the testis was the main site for snake spermiogenesis, and the seminiferous spherule in vas deferens was the other Both the epididymis and vas deferens stored sperm; however, the vas deferens was the main organ for sperm storage.  相似文献   

18.
Y Takeda 《Acta anatomica》1987,128(4):291-294
A light-microscopical study of the histoarchitecture of the human parotid duct was carried out. The parotid duct, much like other excretory passages, possessed three histological coats: mucosa, muscular layer and adventitia. The mucous epithelium was composed of the innermost tall columnar cells and the basal cubical cells. Numerous, circular elastic fibers were in close vicinity to the epithelium. The muscular layer consisted of smooth muscular fibers running in longitudinal direction. The adventitia consisted of lipofibrous connective tissue and contained many vessels. The result of the present study suggests that the parotid duct contributes to control of salivary secretion, since its architecture is basically similar to that of other excretory passages which have peristaltic activity.  相似文献   

19.
In nature, the ascidian Ciona intestinalis sheds spermatozoa at dawn; however, gravid individuals can be induced to spawn at any time by a 1-hr dark-adaptation period followed by 25-min exposure to 415–430 nm irradiation. Spawning can be induced similarly from a preparation of the isolated sperm duct. A combined light and electron microscopic study was initiated to define morphological aspects of the sperm duct complex and, if possible, elucidate the receptor and effector systems. Results of this investigation indicate that the duct is composed of a tubelike epithelium with a distal closure apparatus consisting of approximately 12 tubules encased by, but not in contact with, subepithelial pigmented cells. There are no nerve or muscle elements associated with the complex. A microfilament system oriented circumferentially about the major cell axis and closely allied with numerous small vesicles is present within epithelial cells along the main portion of the duct. A similar system, oriented along the major cell axis, occurs in epithelial cells of the distal tubules. The potential roles of these epithelial cells as both receptors and effectors of the spawning response is discussed, and an hypothesis is presented to account for the mechanism of light-triggered sperm release.  相似文献   

20.
羟基丁酸和羟基己酸共聚酯(poly(hydroxybutyrate-co-hydroxyhexanoate),PHBHHx)以其良好的生物相容性而具有广泛的生物医学应用前景。其降解产物之一寡聚羟基丁酸酯(oligo(polyhydroxubutyrate),OPHB),广泛存在于自然界的生物体中,并承担各种功能。采用甲醇降解法制备OPHB的甲酯衍生物,MTT实验研究OPHB及其甲酯衍生物对人微血管内皮细胞(human mammary epithelial cells,HMECs)代谢活性的作用。研究结果表明,OPHB对HMECs细胞活性有20%的促进作用,在半饥饿培养条件下细胞活性提高了80%。而制备的OPHB甲酯衍生物有一定的细胞毒性细胞代谢活性降低50%。  相似文献   

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