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1.
Some morphological, physiological, and pharmacological properties of the retractor bulbi muscle of the frog were tested. The enzyme-histochemical investigation shows that the retractor bulbi muscle contains twitch muscle fibres only. Two types of twitch muscle fibres, which are especially different in their diameter and in the content of mitochondria, build the muscle in an irregular arrangement; tonic muscle fibres were not observed. On the average, the isolated retractor bulbi muscle has at room temperature a contraction time of 26 ms, a half-relaxation time of 28 ms, a fusion frequency of 75 stimuli/s, and a twitch-tetanus ratio of 0.28. The fatigability of this muscle is higher than in oculorotatory eye muscles but lower than in skeletal muscles of the frog. An increase of the extracellular K+-concentration elicits in retractor bulbi muscles a quickly transient contracture; the mechanical threshold of the muscle fibres is found in a range between 20 and 25 mM K+ in Ringer solution. Similar short-lasting contractures, which are probably caused by twitch fibres, rich in mitochondria, are also evoked by application of depolarizing drugs like acetylcholine. The properties of the retractor bulbi muscle are compared with those of the sartorius muscle of the frog, which likewise contains twitch muscle fibres only.  相似文献   

2.
The orbit of the Upper Devonian piscine osteolepipod Eusthenopteron foordi has a distinct endocranial depression postero-ventrally at the base of the basipterygoid process and lateral to the hypophysis. Compared with what is known of extant osteolepipods, this depression is a myodomus retractricis bulbi. From the evidence of this myodome for attachment of retractor bulbi musculature, the hypothesis is presented that Eusthenopteron foordi had a palpebra tertia and, as a corollary, that it also had a musculus levator bulbi, a glandula palpebrae tertiae and a ductus nasolacrimalis. These annexal eye structures would have made it possible for this pulmonate fish to leave the water to bask without being dazzled by sunlight.  相似文献   

3.
Early compensatory mechanisms between eyelid and eye-retraction motor systems following selective nerve and/or muscle lesions were studied in behaving rabbits. Reflex and conditioned eyelid responses were recorded in 1). controls and following 2). facial nerve section, 3). retractor bulbi muscle removal, and 4). facial nerve section and retractor bulbi muscle removal. Animals were classically conditioned with a delay paradigm by using a tone (350 ms, 600 Hz, 90 dB) as conditioned stimulus, followed 250 ms later by an air puff (100 ms, 3 kg/cm(2)) as unconditioned stimulus. Conditioned eyelid responses generated in the absence of the facial motor system (i.e., by the almost sole action of the retractor bulbi motor system) presented a wavy profile, due to the succession of eye-retraction movements. Learned eyelid responses generated in the absence of the eye-retraction motor system (i.e., by the almost exclusive action of the facial motor system) were similar to those of controls, but were reduced in amplitude and peak velocity. Finally, the isolated action of the extraocular recti muscle produced very small eyelid movements during both reflex and learned eyelid responses. Although each of these motor systems could act independently of the others, the motor result of their joint action did not coincide with the simple addition of their separate actions. Both facial and eye-retraction motor systems appear to be necessary for normal eyelid closure during blinking in rabbits. Central reorganization to compensate for loss of either of these systems may explain why the response of each system in isolation cannot be added linearly to obtain normal blink response magnitudes and profiles.  相似文献   

4.
目的研究奶牛阴道菌群,并从健康奶牛阴道分离出产酸能力很强的乳酸菌。方法采用常规的方法对奶牛阴道进行细菌的分离及鉴定,并进行菌群分析。结果健康奶牛阴道优势菌群主要为乳酸菌(P<0.01),屡配不孕奶牛阴道优势菌群主要为金黄色葡萄球菌(P<0.01);从健康奶牛阴道分离出的乳酸菌为55株,其中产酸能力很强的6株乳酸菌鉴定结果分别为Lactobacillus plantarum、Lactobacillus brevis、Enterococcus faecalis、Lactococcus garvieae、Lactobacillus kitasatonis和Lactobacillus amylovorus。结论奶牛阴道菌群中分离的6株乳酸菌可作为潜在的奶牛阴道微生态制剂进行深入研究。  相似文献   

5.
Female mice of the C57 Black/Tw strain given 5 daily injections with 100 microng testosterone (T) or 5 alpha-dihydrotestosterone (DHT) from the day of birth showed estrogen-independent persistent proliferation and cornification of the vaginal epithelium in adulthood. The vaginal epithelium of the mice was essentially similar to that of the controls in histological structure during or shortly after neonatal injections of the androgens. In T- and DHT-mice aged over 20 days, however, a marked proliferation with or without superficial cornification took place in the epithelium lining the proximal and middle parts of the vagina (Müllerian vagina), while neither proliferation nor cornification occurred in the epithelium of the distal vagina (urogenital sinus vagina). On the second day of postnatal life in mice given a single injection with T on the day of birth, the mitotic activity in the epithelium of the middle vagina was heightened, but it dropped to the control level on the third day and remained low until 20 days. By contrast, the mitotic rates in the epithelium of the rest of the vagina in T-mice and of all parts of the vagina in DHT-mice were approximately the same as in the controls until 20 or 30 days. The mitotic rates in the epithelium of the Müllerian vagina were markedly elevated in T-mice at 20 days of age and DHT-mice at 30 days, and thereafter remained almost unchanged until 60 days of age. These results were different from the findings in mice given neonatal injections with the dose of estradiol-17 beta (E) capable of estrogen-independent vaginal cornification (Iguchi et al., 1976). The present finding seem to indicate that the mechanism involved in the induction of estrogen-independent vaginal changes by neonatal administration of androgen (T, DHT) is different from that following neonatal treatment with estrogen (E), although androgen and estrogen act directly on the vaginal epithelium of neonates.  相似文献   

6.
Toll-like receptors (TLRs) are a critical component of the innate immune response in many vertebrates, including avian species. The recent findings of chicken TLRs (cTLRs) expression in ovarian follicles and in the chicken ovary in vivo, as well as the changes in their expression in response to lipopolysaccharide or Salmonella enteritidis (SE) infection, have broad implications for reproductive physiology and for the prevention of transmission of zoonotic diseases to humans through the consumption of contaminated poultry eggs. Because the main route of egg contamination is from infection of the oviduct and mainly from the vagina, the aim of this study was to investigate the expression of the ten cTLRs identified to date in the chicken oviduct in vivo, to determine whether sexual maturation affects their mRNA abundance and to investigate whether SE infection alters the expression of TLRs in the chicken vagina. RNA was extracted from the vagina of healthy prepubertal, sexually mature and aged birds, and from sexually mature and aged SE infected birds. RT-PCR analysis revealed that all types of cTLRs apart from TLR1-1 were expressed in the vagina of sexually mature birds. Quantitative real-time PCR analysis revealed that the mRNA abundance of TLR2-1, 2-2 and 4 differ with respect to sexual maturation in the chicken vagina. SE infection resulted in a significant induction of TLR5 and 15 in the vagina of sexually mature birds, and in a significant induction of TLR2-1, 4 and 15 in the vagina of aged birds, while a significant down-regulation was observed for TLR7 in the vagina of sexually mature birds. These findings suggest that a TLR mediated immune response mechanism exists in the chicken vagina, playing a crucial role in preventing microbial pathogens from being incorporated into newly forming eggs.  相似文献   

7.
门诊妇女阴道乳酸菌对临床常用抗生素耐药性的初步研究   总被引:1,自引:0,他引:1  
目的研究临床常用抗生素类药物对妇女生殖道正常菌群乳酸菌的影响,为临床医生选用抗生素治疗妇科疾病提供初步参考,并为微生态学治疗和预防相关疾病提供理论依据。方法采用K-B法(纸片扩散法),以临床采集到的12株阴道乳酸菌为试验菌,研究其对临床常用9大类13种抗生素的耐药性。结果在所测试的抗生索中,试验菌对甲硝唑形成的耐药环直径最小,对头孢噻肟形成的耐药直径最大。除甲硝唑外不同菌株对不同抗生索形成的耐药环直径差异较大。结论在该试验的条件下,乳酸菌对甲硝唑耐药性最强,可作为治疗阴道感染的首选药物;乳酸菌对头孢噻肟最敏感,因而在治疗阴道感染时,应尽量避免使用该药物。  相似文献   

8.
A recessive mutation causing imperforate vagina in mice   总被引:1,自引:0,他引:1  
A recessive mutation (ipv) causing imperforate vagina was discovered in a line of mice selected for low lean tissue mass as a proportion of body weight. Two full sisters were found to have marked swelling of the perineum and complete closure of the vagina. Crosses of heterozygotes identified by progeny testing produced a female progeny ratio not different from the 3 normal: 1 affected (chi 2 = 0.695; p less than .3) expected on the basis of a recessive allele at a single autosomal locus. As a consequence of the imperforate vagina, the uterus and vagina were greatly distended by fluid. The uterus of affected females displayed a swollen uterine lumen and thin endometrial stroma and muscularis. Ovarian tissue of affected females was similar to that of normal mice, and affected females produced ova that were normal in appearance. The mutation causing an imperforate vagina may present a useful model for studying the basis of abnormal vaginal development in other species and increasing the understanding of normal vaginal development in the mouse.  相似文献   

9.
An 11-yr-old captive-raised male woodchuck (Marmota monax) presented with ataxia, poor balance, left-sided weakness, circling to the left and nystagmus with the fast-phase directed towards the left. The clinical signs were compatible with a central vestibular deficit syndrome. Necropsy and histologic findings revealed a meningotheliomatous meningioma centered over the ventrolateral left pons and medulla along with acute bronchopneumonia, chronic glomerulopathy, interstitial nephritis, and phthisis bulbi.  相似文献   

10.
The bacteriological study of vaginal microflora in 24 clinically healthy girls aged 7-8 years was carried out. Two criteria of normal vaginal biocenosis in girls of prepuberal age were proposed. The proportion of hemolytic bacteria in the vagina of a girl of prepuberal age could reach 100% of all microflora, provided the total bacterial count (TBC) exceed average values. A high proportion of hemolytic bacteria in the vaginal microflora of girls of prepuberal age in combination with a high level of TBC (even with TBC not exceeding the upper limit of its normal value) could probably by regarded as a border state. No fungi of the genus Candida should be isolated from vagina in girls of prepuberal age. Facultative anaerobic microflora was represented mainly by Staphylococcus epidermidis and S. saprophyticus. In 64.3 +/- 12.8% of cases bifidobacteria were detected in the girls vagina.  相似文献   

11.
Oestrous ewes (N = 202) were inseminated with 0.1 ml of semen containing 500 X 10(6) motile spermatozoa and the spermatozoa were flushed from their vagina either immediately or 0.25, 0.5, 1, 2, 4 and 8 h after insemination. Pregnancy was determined by returns to service and laparoscopy. Some ewes became pregnant (10.71%) after spermatozoa had been flushed from the vagina only seconds after insemination and about 40% of ewes became pregnant after spermatozoa had been in the vagina for 15 min. Maximum conception (55%) was achieved when spermatozoa had been in the vagina for at least 2 h. It was concluded that the losses of spermatozoa that occur from the vagina will not influence the chance of a ewe conceiving because sufficient spermatozoa to ensure a normal conception move up the reproductive tract before large losses from the vagina take effect.  相似文献   

12.
In a series of experiments spermatozoa were inseminated blindly into the vagina of ewes and then recovered at varying times after insemination. Most of the spermatozoa inseminated were lost by drainage through the vulva. The rate of loss was not affected by the motility of spermatozoa or oestrous state of the ewe. Initially after insemination the loss was not rapid with 82% of the insemination 18% of spermatozoa remained and by 12 h 10% remained. Spermatozoa were removed from the vagina during withdrawal of the penis after intromission and the extent of this loss varied between rams and with the volume of semen already in the vagina. Up to half the inseminate was lost in this way when there was 0.5 ml of semen in the vagina but only 11% was lost when the volume of inseminate was 0.1 ml. The unavoidable loss of spermatozoa may influence the quantity available for fertilizing ova.  相似文献   

13.
14.
Summary Grafts from the vagina and the uterus were transplanted to the anterior chamber of the eye together with crystals of different steroids to investigate whether either the grafted vagina or uterus could be used as indicator of locally produced gestagens.Autologous vaginal and uterine tissues were transplanted into the anterior chamber of the eyes of 199 adult spayed female rats. Crystals of various steroids were placed near to the transplant of the right eye to investigate the local reaction. The steroids used were oestradiol-17, androst-4-ene-317 dione, testosterone, testosterone acetate, progesterone and 3-hydroxypregn-5-en-20-one. The transplant in the left eye served as a control for general reactions. Most of the animals were injected with oestradiol benzoate in order to sensitize the vagina and uterus.The daily injections with 0.1 g oestradiol benzoate produced a typical oestrous picture with a cornified epithelium both in the vagina in situ and in the grafts. The oestrous reaction increased when oestradiol crystals were implanted or when higher doses of oestradiol benzoate were injected.When testosterone or testosterone acetate was implanted in the eye the epithelium of the vaginal transplant was thinner than when only oestrogen had been given.When androsteredione crystals were used, the epithelium of the transplanted vagina was either a rather thick, non-cornified epithelium or a stratified squamous epithelium. In both epithelia mucus could be found in the cells in the upper-most layers.Implantation of progesterone changed the oestrous picture. The epithelium consisted of only 2–3 layers of cells. The upper-most layer or layers presented small to large swollen columnar mucin cells.When pregnenolone crystals were used, the grafted vagina reacted as in the progesterone series though more weakly.The uterus was not suitable for transplantation as it mostly changed into a cystic undifferentiated structure.The vagina in situ and the vaginal graft in the left eye which was not supplied with a steroid showed no characteristics that were marked and constant for any of the steroids except for the oestrogen.In the uterus in situ the gestagens, especially progesterone, caused a stimulation of the stromal cells. Their nuclei became vesicular and showed fine chromatin particles.The investigation was supported by grants from the Medical Faculty of Lund and The Royal Physiographic Society of Lund.  相似文献   

15.
Ultrastructural characteristics of the cirrus sac and vagina of progenetic and monoxenic spathebothriidean tapeworm, Diplocotyle olrikii from the body cavity of Gammarus oceanicus are described. Five loosely arranged muscle layers make up the cirrus sac wall. The nucleated syncytial cytoplasm of the ejaculatory duct's wall has apical lamellae and 3 well-developed muscular layers under epithelim. Numerous prostate ducts pass through syncytial epithelium of it. The numerous prostate glands are localized around cirrus sac. Unique morphology of the prostate granules with an electron-dense core surrounded by a matrix of lower density is revealed for the spathebothriidean tapeworms. The epithelial lining of the cirrus in D. olrikii is nucleated and also is connected to subsurface sunken perikarya. The apical surface of the cirrus is covered with small cone-shaped microtriches. Well-developed 10 closely arranged muscle layers support the cirrus. Three regions of the vagina are distinguished. The distal part of vagina has filamentous microthrix type on the surface similar to tegumental one, as well as middle and proximal regions are covered with small cone-shaped microtriches, reducing in their number to proximal part. Anucleate epithelial lining of vagina is connected to numerous sunken parikarya. The cirrus and vagina epithelial lining has numerous vesicles. A comparison is made of the fine structure of the cirrus sac and vagina of monoxenic and dixenic spathebothriidean species. Ultrastructural data on the cirrus sac and vagina of the Spathebothriidea are compared with those for monozoic and polyzoic cestodes. The ultrastructural spathebothriidean features are discussed.  相似文献   

16.
Jalakas M 《Theriogenology》2000,54(8):1281-1284
Papyraceous, mummified fetal membranes were found in the vagina of a cow at the end of the fourth month after a normal delivery. The uterus and cervix were without any pathological changes. The cow conceived on Day 36 after removal of the mummified fetal membranes upon the second insemination. Apart from the uncommon nature of the case, it proves that after calving the bovine vagina can maintain a sterile environment and that the constrictive mechanism of the vagina can be strong enough to hinder for a long time the discharge of fetal membranes and access of microbes to the vagina.  相似文献   

17.
The effects of ovarian hormones on the vaginal population of Pasteurella pneumotropica in rats were investigated. Specified-pathogen-free adult female Wistar-Imamichi rats with a 4 day oestrous cycle were inoculated with P. pneumotropica in the vagina. Cyclic changes in the vaginal population of P. pneumotropica were not observed in ovariectomized rats and the bacterial population was at a similar level to that at normal dioestrus. Administration of oestrogen to ovariectomized rats caused an increase in the numbers of P. pneumotropica and total bacteria in the vagina nearly equal to that at oestrus in intact rats. The numbers of these organisms in the vagina of ovariectomized rats treated with progesterone did not change and were similar to those of control ovariectomized rats treated with sesame oil. Vaginal smears of ovariectomized rats treated with oestrogen were characterized by abundant cornified non-nucleated epithelial cells with many adherent Gram-negative coccobacilli and were similar to smears from intact rats at oestrus. These findings suggest that the proliferation of P. pneumotropica at oestrus in rat vagina may be primarily due to the environment provided by the degeneration of vaginal epithelial cells promoted by oestrogen secretion from the ovaries.  相似文献   

18.
1800例妇科门诊患者阴道分泌物的病原学分析   总被引:2,自引:0,他引:2  
目的了解妇科门诊患者中阴道分泌物的病原学。方法用湿片法进行阴道分泌物及细菌性阴道病(BV)检查,革兰染色法检查G^-双球菌。观察分泌物的病原体分布情况。结果1800例妇科门诊患者中,其阴道分泌物假丝酵母菌阳性549例,阳性率为30.50%;阴道毛滴虫阳性34例,阳性率为1.89%;BV399例,阳性率为22.17%;G^-双球菌16例,阳性率为0.89%。混合感染:假丝酵母菌合并阴道毛滴虫感染2例(0.11%);假丝酵母菌合并BV192例(10.67%);假丝酵母菌合并G^-双球菌5例(0.28%);假丝酵母菌合并BV和G^-双球菌3例(0.17%)。结论妇科门诊患者阴道分泌物的病原体构成复杂,阴道炎主要以外阴阴道假丝酵母菌病和BV为主,部分可多种病原体混合感染。  相似文献   

19.
This investigation evaluated immunity to vaginal herpes simplex virus type 2 (HSV-2) infection after local or parenteral immunization with attenuated HSV-2. Vaginal immunization induced sterilizing immunity against challenge with a high dose of wild-type virus, whereas parenteral immunizations protected against neurologic disease but did not entirely prevent infection of the vagina. Vaginal immunization caused 86- and 31-fold increases in the numbers of immunoglobulin G (IgG) plasma cells in the vagina at 6 weeks and 10 months after immunization, whereas parenteral immunizations did not increase plasma cell numbers in the vagina. Vaginal secretion/serum titer ratios and specific antibody activities in vaginal secretions and serum indicated that IgG viral antibody was produced in the vagina and released into vaginal secretions at 6 weeks and 10 months after vaginal immunization but not after parenteral immunizations. In contrast to the case for plasma cells, the numbers of T and B lymphocytes in the vagina were similar in vaginally and parenterally immunized mice. Also, lymphocyte numbers in the vagina were markedly but similarly increased by vaginal challenge with HSV-2 in both vaginally and parenterally immunized mice. Lymphocyte recruitment to the vagina after virus challenge appeared to involve memory lymphocytes, because it was not observed in nonimmunized mice. Thus, local vaginal immunization with attenuated HSV-2 increased the number of IgG plasma cells in the vagina and increased vaginal secretion/serum titer ratios to 3.0- to 4.7-fold higher than in parenterally immunized groups but caused little if any selective homing of T and B lymphocytes to the vagina.  相似文献   

20.
Exposure of female mice to estrogenic substances during the neonatal period induces developmental defects in the reproductive tract such as estrogen-independent persistent proliferation of the vaginal epithelium, which often leads to carcinogenesis in adulthood. In this study, several estrogen-regulated genes have been identified in the neonatal mouse vagina by DNA microarray hybridization analysis. Among the genes up-regulated in the developing vagina by a high dose of estrogen, trefoil factor 1 (TFF1), a mucin-associated gastrointestinal growth factor, showed a unique expression pattern in accordance with the irreversible changes induced by neonatal estrogenization in the vagina. Vaginal expression of TFF1 mRNA was markedly increased by estrogen in neonatal mice but not in adults, and pronouncedly intensified expression of the gastrointestinal gene was observed in the vagina of neonatally estrogenized mice even at adulthood. The specific localization of TFF1 protein in the epithelium of neonatally estrogenized vagina was confirmed by immunohistochemistry. Moreover, without any obvious alteration in the expression of gel-forming mucin genes, the lumen of the neonatally estrogenized vagina became filled with periodic-acid-Schiff-stained mucinous gel, which was possibly caused by the overexpression of TFF1. Thus, estrogen acts directly on the developing vagina in the permanent induction of TFF1 gene expression, and the gene induction does not appear to be related to hypermethylation of the cis-promoter of the TFF1 gene. TFF1 may be a useful marker for developmental estrogenization syndrome of the mouse vagina. This work was supported by a Grant-in-Aid for Encouragement of Young Scientists from the Ministry of Education, Science, Sports, and Culture, Japan, and grants from the University of Tsukuba to M. M.  相似文献   

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