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1.
The present study is concerned with the effect of radiation to the testis on fertilizing ability in vitro using golden hamster spermatozoa. Male hamsters at 6 and 8 weeks of age were given acute testicular X-irradiation (200 kVp, 20 mA, 0.47-0.48 Gy/min). Spermatozoa were collected from the cauda epididymides at different times after irradiation and then they were suspended in fertilization medium. After preincubation for 4-5 hr, the spermatozoa were cultured with the eggs collected from mature hamsters treated with PMSG-hCG. Fertilized eggs were examined for incidence of sperm penetration and formation of pronuclei at 4-5 hr after insemination. The fertilization rate (47.7%) at the 6th week after irradiation with a dose of 2 Gy was much lower in comparison with the control value (92.6%). However, the fertilization rates at the 3rd and 9th weeks after irradiation were 97.7 and 90.6%, respectively. In these period, no difference was found between the irradiated groups and the control groups. From the changes in sperm concentration after irradiation with a dose of 2 Gy, it was found that the fertilization rate was the lowest at the 6th week. The sensitive stage to radiation during spermatogenesis with reference to the reduction of fertilizing ability after irradiation coincides with that of decrease in the sperm concentration and sperm motility. The results of fertilization rate at the 6th week after different doses of X-irradiation (0.25-6 Gy) indicated that the reduction of fertilization rate is nearly expressed as a dose-response relationship.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
Fetal DNA in maternal plasma and serum has been shown to be a useful material for fetal gender determination and for screening tests for abnormal pregnancies except during early gestational ages. Maternal serum samples were obtained from 81 pregnant women during the 5th-10th weeks of gestation. Fetal gender was determined by conventional polymerase chain reaction (PCR) to detect a Y-chromosomal sequence (DYS14) in maternal serum during early gestation and confirmed by examination of the newborns after delivery. Real-time quantitative analyses of the SRY and beta-globin genes were also performed in order to determine fetal gender and to quantify fetal DNA concentration in maternal serum during early gestation. When using conventional PCR, the total sensitivity of identifying a male fetus was 95%, but its sensitivity after the 7th week was 100%, whereas in real-time quantitative PCR, the total sensitivity after the 5th week was 100%. Quantitative analyses of the SRY gene revealed that the mean concentration of fetal DNA in maternal serum was 30.55 copies/ml, that fetal DNA concentration showed a tendency to increase with the progression of pregnancy, and that it had a wide normal range. Thus, we could confidently determine fetal gender by using maternal serum samples taken as early as the 7th week.  相似文献   

3.
Autoradiographic study of an experimentally-induced tumour following local irradiation in a dose of 600 rad showed no retardation of the cell cycle 6 to 12 hours after the irradiation. Marked reduction of the mitotic index (MI) and of the labeled nuclei index (LNI) was noted to the 96th hour after the irradiation. In repeated irradiation in a dose of 1200 rad at an interval of 18 hours there was revealed a marked reduction of the MI and of the LNI as a result of the block of the passage of cells from the G1-period into S. However, restoration of the cell proliferation uas noted by the 24th-48th hours. A high MI revealed at all the periods of investigation after repeated tumour irradiation at an interval of 24 hours was possibly caused by an increase in the time of mitosis proper, this also being confirmed by a significant accumulation of the number of late mitotic phases.  相似文献   

4.
Hunter syndrome: prenatal diagnosis in maternal serum.   总被引:1,自引:0,他引:1       下载免费PDF全文
Iduronate sulfate sulfatase (ISS), the deficient hydrolase in Hunter syndrome, consistently increases in the serum of pregnant women, reaching a three- to fourfold increase from pre-pregnancy levels toward the end of pregnancy. In Hunter carriers, a correlation occurs between the status of the fetus with regard to Hunter syndrome and the ISS increase in maternal serum. Thus, in pregnancies with Hunter-affected fetuses, enzyme levels did not change in the serum of heterozygous mothers until abortion was performed, while in nonaffected fetuses, ISS increased usually very early in pregnancy--as early as the 6th-12th week. In heterozygote female fetuses, this increase might be delayed. These data imply that a prenatal diagnosis of Hunter syndrome might be accomplished in maternal serum at early conventional procedures for the prenatal diagnosis of Hunter syndrome.  相似文献   

5.
The influence of pollen irradiation on the production of in vitro haploid plants from in situ induced haploid embryos was investigated in winter squash (Cucurbita maxima Duchesne ex Lam.). Pollen were irradiated at different gamma-ray doses (50, 100, 200 and 300 Gray) and durations (9, 11, 15, 21, and 28 July). Production of in vitro haploid plantlets was influenced by irradiation dose, irradiation duration, genotype, and embryo type and embryo stage. Embryos were only obtained from lower irradiation doses (50 Gray and 100 Gray) and earlier irradiation durations (9, 11, and 15 July). The greatest embryo number per fruit was procured from “G14” and “55SI06” genotypes at 50 Gray gamma-ray dose. Necrotic embryos were higher than normal embryos at delayed harvest times (5 and 6 weeks after the pollination). The convenient harvest time for embryo rescue was observed about 4 weeks (between 25 and 30 days) after pollination. All cotyledon and amorphous embryos had only diploid plants while late-torpedo, arrow-tip, and pro-cotyledon embryos produced 33.3, 50.0, and 66.7% haploid plant. The frequency of haploid plantlets was 0.11, 1.17, 10.96 and 0.28 per 100 seeds, 100 embryos, 100 plantlets and a fruit at 50 Gray gamma-ray dose, respectively.  相似文献   

6.
With the aim to reveal the ionising radiation effect to formation and structure of the optic nerve (ON), 55 white rat intact embryos and fetuses and 77 experimental embryos and fetuses, subjected to x-ray irradiation on the 10th-14th day of development, have been studied. The main regularities in formation of the ON have been stated under normal conditions. Certain disturbances in formation of the ON and in the internal membrane of the optic vesicle (future retina) under effect of x-rays in the dose of 2.24 Gy have been detected during the intrauterine period of development--folds, rosellas of retina, retardation in differentiation of the retina nervous layer, aberration of the ON growth with a subsequent reduction, the ON hypo- and aplasia, retardation in formation of neural sheaths, absence of intraspace between the sheaths.  相似文献   

7.
Ante- and postnatal development of anatomical structures and cells of lymphatic nodes has been studied in rat offspring subjected to tetracycline effect during placentation and organogenesis (the 8th-14th days) and during fetogenesis (the 15th-20th days). Tetracycline injection during the 8th-14th days of embryogenesis results in certain disturbances of the nodular structure formations, inhibition of lympho- and plasmo-cytopoesis against the background of a sharp increase in number of basophilic granulocytes and tissue basophils. The antibiotic effect on the 15th-20th days of embryogenesis does not disturb the lymph node formation, but produces an increasing number of lymphocytes, plasmocytes, macrophages, eosinophilic granulocytes and tissue basophils in them.  相似文献   

8.
The authors showed a pronounced and stable decrease in sexual motivation of male rats immediately after gamma-irradiation of the head with a dose of 2.58 C/kg. Exposure of the body to 1.29-2.58 C/kg radiation also inhibited sexual behaviour but only by the 45th-55th minute following irradiation: with higher doses some increase in sexual activity was observed immediately after irradiation.  相似文献   

9.
Embryogenesis of Payer's patches (PP) of the ileum, has been studied in 183 human fetuses 8-40-week-old. Their anlages appear on the 8th-9th week as an accumulation of atypical villi. At first the PP are localized in the cranial part of the ileum, and then spread caudally. Their most active increase in amount takes place from the 15th up to 17th weeks of development. From the 8th up to the 40th weeks the PP amount increase from 10 up to 37. During the same time their length develops from 0.7 up to 8.3 mm, their width--from 0.3 up to 2.2. The first lymphoid nodules++ in the PP are detected on the 14th week, then their number rises from 200 up to 3,500. The superficial area of all the PP, turning into the lumen of the ileum widens from 1.4 up to 620 mm2. Their predominate form is ellipsoid. During the whole prenatal period in the lymphoid nodules++ no germinative centers are revealed. Lymphocytes in the PP are identified in 8-9-week-old fetuses. By the 29th week the whole amount of lymphocytes in them increase up to 9.6 x 10(6) cells. Lymphocytic suspension of the PP of 8-9-week-old fetuses contains 1.7% of T-lymphocytes (E = POK) and 0.1% of B-lymphocytes (EAC = POK). By the 29th week their amount increases up to 9% and 7%, respectively, but by birth it does not reach their amount in the PP of mature organisms.  相似文献   

10.
Developmental peculiarities of the tongue as a whole and its main structural elements (muscles, membranes, glands, lingual tonsil) have been studied in 120 human embryos and fetuses 5-week-old--9-month-old. Transmissive electron microscopy, electron histochemistry (for estimation of 5'-nucleotidase activity), staining of semithin slices with toluidine blue and aniline++ pink have been applied. Problems on migration of myogenic elements in the developing tongue have been discussed. Ultrastructure of gustatory bulbs of the human fetus tongues has been investigated. A complete formation of the tongue takes place by the 8th-9th months of the prenatal development.  相似文献   

11.
The influence of hadacidin, a model substance for induction of cheilognathouranoschisis in rat fetuses (2,550 mg/kg b.m. at gestation day 12), ultraviolet irradiation (UVB) of blood (1 week before gestation) and thiamine (25 mg/kg b.m. from gestation days 12 to 15) on the prenatal development of rats at the 20th day of gestation was investigated. Using the body mass and the hepatic GGT-activity as parameters. Hadacidin caused a distinct retardation of the fetal somatic development. Partially, the embryotoxic effect was compensated by UVB or thiamine. The combination of both procedures was more effective. There is a good correlation between the maturation grade of fetuses at day 20 of gestation and the hepatic GGT activity.  相似文献   

12.
One hundred and twenty white rat embryos 13-22-day-old have been irradiated with x-rays (the dose 250 R) on the 12th-14th day of embryogenesis. The embryos have been divided into series of sagittal, frontal, transversal sections and stained by means of general histological methods. The irradiation performed on the days mentioned does not affect formation of the paramesonephric ducts. In all the experimental animals the caudal end of the paramesonephric duct is separated from the mesonephric duct as a solid cellular cord in which the lumen appears later. In the experimental females the disturbances developed after irradiation are manifested first of all in retardation of the main stages of the organ's formation; the retardation is observed: in fusion of the paramesonephric ducts, in resorption of the medial septum between the fused ducts, in separating the sinuous part of the vagina from the urogenital sinus, in recanalization of the vaginal epithelial cord. More severe lesions are presented as agenesia of the vaginal sinuous part and as its atresia represented by a transversal septum of the organ. The disorders in the vagina development are depended on massive primary necrobiotic radial lesions of the mesenchymal cells around the epithelial anlages of the small pelvis.  相似文献   

13.
为了进一步探讨胰岛淀粉样多肽(IAPP)的分布、定位以及它与其他生物活性物质的关系;用IAPP组织化学PAP邻片双标法,观察了18例14~38周人胎气管内IAPP免疫反应(IR)细胞的个体发生及与5羟色胺(5-HT)的关系。结果显示,胎14周,气管粘膜表面的假复层柱状上皮中已有IAPP-IR细胞(Fig.1&2);15周开始,粘膜固有层气管腺导管上皮中也出现分散的IAPP-IR细胞(Fig.3);随胎龄增长,17~21周,气管上皮内IAPP-IR细胞逐渐增多;免疫染色加深(Fig.4&5),有些细胞发出细突直达腔面(Fig.6&7),粘膜下层的气管腺腺泡中也有IAPP-IR(Fig.8); 22~38周,气管内 IAPP-IR 细胞又呈逐渐减少趋势,IAPP-IR仅出现在基底锥形细胞中(Fig.9&10),且免疫染色较深。邻片未显5-HT-IR。本研究表明,人胎儿期气管上皮细胞内有IAPP的表达;且IAPP-IR细胞随胎期的发育而发生变化。  相似文献   

14.
Time of appearance, succession and ultrastructural peculiarities of pancreatic endocrinocytes have been studied in human embryogenesis. A-insulocytes (the 7th-8th week) appear before B-endocrinocytes (the 9th-10th week). Before the 10th week A-insulocytes possess a higher degree of cytodifferentiation and development of the mechanisms necessary for hormones secretion. This should be taken into account at allotransplantation of the embryonal pancreas with the aim to correct insulin insufficiency.  相似文献   

15.
In 40 series of histological sections performed in human embryos and prefetuses from 4 up to 20 weeks of development, as well as in 20 corpses of fetuses and stillborns, it has been stated that the anlage of the thoracic duct appear in 6-7-week-old fetuses as lymphatic clefts surrounded with mesenchymal cells that are situated near large veins in the areas of the most active morphogenesis. Connecting with each other, the clefts form the jugular and retroperitoneal lymph sacs and a well branching network of canals. From the latter, on the 7th-8th week of development a plexus of lymph vessels appear, and later on (on the 8th-9th week)--bilaterally situating trunks of the thoracic duct. Further development of the thoracic duct is connected with the lymph nodes formation, their germs appear on the 9th-10th week along the course of the left trunk, as well as along the ductal branches and anastomoses. The formation of the lymph nodes results in reduction of some trunks and plexuses of the thoracic duct. Owing to this, its form in 14-15-week-old prefetuses resembles the one in newborns. Disturbances in the formation processes of the lymph nodes along the course of the reducing ductal areas, as well as their formation along the course of its main trunk can result in various structural variants of the thoracic duct in children and grown-up persons. Histogenesis of the thoracic duct wall and formation of the lymph nodes are not completed by birth.  相似文献   

16.
It has been established that tissue cooling to 15-20 degrees C brings about a short-term spasm of smooth muscles of the intestine, peripheral vessels and of the visceral vessels, replaced by an appreciable spasmolytic effect at the 5th-8th minute of hypothermia. The maximal hyperemia develops by the 15th-20th minute of the cooling and persists over the whole period of the cooling. It is assumed that inhibition of oxidative phosphorylation in the mitochondria of the smooth muscles underlies the spasmolytic action of cold. In addition, cold produces a marked hypocoagulation effect.  相似文献   

17.
The dynamics of malonic dialdehyde (MD) dependence in the blood serum of Vistar line male rats on the intensity of irradiation after a total single irradiation with 60Co gamma-quantums in 1.0 and 5.0 Gy doses (during 30 days); 9.0 Gy (during 15 days) were studied. The MD contents values both in the norm and in 0.5, 1, 2, 4, 6, 8, 10, 15, 20 and 30 days after irradiation are given. The experimental data demonstrated the different sensitivity of the final LPO parameters to the doses of 1.0, 5.0, 9.0 Gy radiation depending on the dose power, the changes of these parameters being kept for a long time after irradiation.  相似文献   

18.
Histological, histochemical and neurochemical methods were used in order to study the features of the histogenesis of structures of the atrioventricular area of the conducting system of the heart and the formation of their cholinergic innervation in the postnatal period of the hog. Under study were 175 hearts of embryos of the hog at the age of 3, 4, 5, 6, 8, 10, 12, 14 and 15 weeks and 22 hearts of adult hogs. The formation of different areas of this system was shown to be asynchronous. The atrioventricular fascicle is formed during the 4th week, the atrioventricular node -- during the 6th week and the conducting muscle fibres--during the 8th week of embryogenesis. The fascicle and the node have a complicated structure and different cellular composition. In the process of prenatal ontogenesis the increased amount of glycogen and increased activity of phosphorylase were noted in the cytoplasm of myocytes of the atrioventricular area of the conducting system of the heart. The cholinergic nerve fibres grow up to the structures of the atrioventricular area of the conducting system of the heart during the 6th week of embryogenesis, and by the end of the prenatal development they form a thick network in all its structures.  相似文献   

19.
By means of morphometric techniques, peculiarities in formation of the hypophyseal-thyroid system during prenatal and early postnatal periods have been studied in lemmings (Dicrostonyx torquatus) from the Wrangel island at growth stages and at the peak of the population quantity. Folliculoformation rate, time when the organ reaches the definitive structure, periods for establishing connection with the regulating center--the anterior hypophyseal lobe, correlation of differentiation rates of histo- and ultrastructures of the organ distinctly react to changes in the density population of the animals. Periods of initiation of folliculoformation are early and comparable at both stages of the population cycles. However, further at the peak of the population quantity, an essential retardation in the development of both histo- and ultrastructures of the thyroid cells is observed; formation of the histostructure significantly overtakes differentiation of the ultrastructures composing its cellular elements. The follicular structure begins to form only in newborn animals, the folliculogenesis completes on the 1st-6th days of the postnatal period. At the stage of growth of the population quantity, the folliculogenesis lasts 2 days (the 15th-17th days of the prenatal development), the organ's structure becomes definitive on the 17th day, at the same period connections are established with the anterior hypophyseal lobe. The role of the thyroid hormones in formation of reprodactive and adaptive potencies of the organism at various stages of the population cycle is discussed.  相似文献   

20.
A comparison of cortisol and ACTH level determination in 82 human fetal sera obtained in the 11th-34th week of the intrauterine development and 50 sera from infants 1-7 days of age has revealed several stages of pituitary-adrenal system (PAS) maturation. PAS is immature in the first trimester of embryogenesis when cortisol concentration in the human fetal blood is low. The functional relations between pituitary and adrenal glands begin to establish in the middle of prenatal developmental period. A prominent response to delivery stress indicates that by delivery PAS reaches a certain stage of maturation. The feedback between ACTH and cortisol secretions in the blood of infants 1-7 days of age demonstrates that the refractory period of PAS is absent in the neonates during the first week of their life.  相似文献   

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