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1.
A group of 344 cervices, produced by conisation within a period of 5 1/2 years, were examined for specific effects of contraceptives. In half of all women, who used oral contraceptives, specific lesions such as "siebartige polypoide Hyperplasie" (cribriform polypoid hyperplasia) were found. The findings and their etiology and importance are discussed.  相似文献   

2.
OBJECTIVES: Our purpose was (1) to determine whether the human cervix is capable of producing interleukin-8 in vitro and to examine the possibility of stimulating an increase in any such output and (2) to examine the concomitant production of prostaglandins. STUDY DESIGN: Cervical tissue was obtained from 48 women, 29 pregnant women undergoing surgical termination of pregnancy (20 of whom were treated with the prostaglandin analog Cervagem), 14 nonpregnant, premenopausal women, and three postmenopausal women. Explants were cultured and the medium was assayed for interleukin-8 and prostaglandin E2. Analysis of variance and Newman-Keuls statistical tests were used. RESULTS: Significant quantities of interleukin-8 were produced by the tissue, and the data indicate that cervical explants from pregnant and nonpregnant women behave in a similar way when challenged by phorbol myristate acetate but that the postmenopausal cervix loses its capacity for interleukin-8 production. CONCLUSIONS: Human cervix is capable of producing large amounts of interleukin-8 in vitro, and it may be influenced by the steroid hormones. Thus interleukin-8 could be an excellent candidate for a prime role in neutrophil-mediated cervical ripening.  相似文献   

3.
A large-scale study was undertaken to investigate the effects of two systematic anthelmintic treatments on village cattle productivity in the Gambia. Treated animals had significantly higher performance in terms of live weights and age at first calving, but the mortality rate of 0- to 1-yr-old cattle appeared to be negatively affected. These results and financial data on treatment costs were used in a herd simulation model to assess the profitability of the intervention. Treatment was profitable on average, but the risks of losing money were large and average returns were sensitive to various hypotheses examined. The treatment regimen studied can only be recommended in certain herds and further research is needed to identify the factors determining the negative response in other herds.  相似文献   

4.
Thirty-three rabbit cell lines were established from various fetal tissues of the inbred strain III of the New Zealand rabbit (Oryctolagus cuniculus). None of these lines exhibited senescence during a growth period of more than 2 years. Karyologic studies of most cell lines at 10 to 20 cell-passage intervals revealed that the karyotype stability of the rabbit cells in vitro was correlated with the organs from which the cell lines were derived. Thus, lines derived from cornea, spleen, and kidney tissues usually contained high frequencies of polyploidy in their early passages, whereas most of those derived from lung and skin were found to retain the normal diploid karyotype for much longer periods of time. One line derived from fetal lung tissue, designated Lung 16, remained diploid up to 100 passages. In late passages of the majority of all the lines studied, the cells became pseudodiploid, hyperdiploid, or polyploid. Among the pseudodiploid and the hyperdiploid cell lines, the chromosomal changes followed three basic patterns: (1) a gain of one or more telocentric chromosomes; (2) a loss of one telocentric chromosome plus a metacentric marker chromosome (M); or (3) a gain of a long telocentric marker chromosome with or without changes in the number of telocentric D chromosomes. By the G-banding technique, the telocentric chromosome involved in these three patterns was identified as the D-group chromosome 18 and the M marker chromosome as an isochromosome of 18. These results suggest that chromosomal rearrangement in rabbit cells involving trisomy of 18 may be responsible for the longevity of these cell lines cultured in vitro.  相似文献   

5.
The authors present the evidence of atherogenic properties of VLDL and LDL potentiation on the model of endothelial cells-human umbilical vein endothelial cells, by preferable stimulation of the endothelial cell to thromboxane A1 production at in vitro conditions by atherogenic lipoproteins. The vasoconstrictive, thrombogenic and atherogenic effects of TXA2 are exerted on the vessel in this way. The ratio prostacycline/thromboxane, decisive for the maintenance of vascular homeostasis, is less than 1, this means the beneficial effect of prostacycline can not be applied. Protective, antiatherogenic effect of HDL and its subfractions HDL2 and HDL3/predominantly through their function in the reverse cholesterol transport from the periphery to the liver, antioxidative influence on LDL, as far as antiaggregation and fibrinolytic effects of HDL/is multiplied by the fact that HDL preferably stimulates the secretion of prostacycline by the endothelial cell. The ratio prostacycline/thromboxane A2 is higher than 1, that means beneficial vasodilative, antiaggregation and antiatherogenic effect of prostacycline on the vessel wall predominate. Quantitative evaluation of antiatherogenic effects of HDL subfractions (HDL2 and HDL3) revealed more significant antiatherogenic effect in HDL2 subfraction-in the sense of prostacycline secretion stimulation and exertion of its beneficial effects on the vessel. (Fig. 5, Ref. 33.)  相似文献   

6.
This study aimed to investigate if pregnancy-induced hypoalgesia occurs in the sow, and to examine the role of endogenous opioids which are known to be released in response to nociception. Sixteen Large White x Landrace multiparous sows were tested in straw bedded pens (2.5 x 2.5 m) during weeks 4, 8 and 12 of pregnancy and over the farrowing period. Testing involved thermal stimulation of eight areas on the rear-quarters of the sows with a CO2 infra-red laser until a physical response was seen (tail flick, leg move or muscle twitch) or for a maximum of 16 s. Over the farrowing period testing was more frequent, and at 3.75 h after the birth of the first piglet, half the sows received an injection (i.m.) of an opioid antagonist naloxone (N) (1 mg kg(-1) body weight) with the remainder receiving a control dose of saline (S). Responses were recorded 15 and 30 min post-injection. There was no significant difference between response times over weeks 4, 8 and 12 of pregnancy (P = 0.152), however a significant rise was seen from week 12 to 5 days before parturition (P = 0.002). Response times continued to rise until the birth of the first piglet by which time the majority of sows had stopped responding within 16 s (P < 0.001). Response times fell over days 1, 2 and 7 post-partum. After administration of naloxone response times fell compared to control animals at 15 min (P < 0.001) and 30 min (P < 0.01) post-injection. These results suggest that nociceptive threshold increases during late pregnancy in the sow, perhaps as an endogenous defence against labour pain, and that during parturition this change in nociceptive threshold is, at least in part, opioid-mediated. Oxytocin is known to be inhibited by endogenous opioids at parturition, thus future research should consider the potential role of increased nociception at birth as a negative feedback to oxytocin release.  相似文献   

7.
8.
BACKGROUND: Gliadin amino acid sequence(s) responsible for toxicity in susceptible individuals have not been fully elucidated. Previous in vitro studies have suggested the presence of active sequences in the NH(2)-terminal part of the A-gliadin molecule. In this paper the in vitro activity of A-gliadin synthetic peptides 31-55, 31-43, and 44-55 has been investigated. METHODS: Organ culture of jejunal mucosa from untreated and treated coeliac patients was used. In the first system enterocyte height was used as a measure of peptide toxicity; in the second system evidence of activated mucosal cell-mediated immune response was sought. RESULTS: Peptides 31-55 and 31-43 were active on untreated coeliac mucosa at a concentration of 0.5 mg/ml and peptide 44-55 only at a concentration of 3 mg/ml. In in vitro-cultured treated coeliac mucosa peptides 31-55 and 31-43 at 1 mg/ml and peptide 44-55 at 3 mg/ml were able to induce enhanced epithelial expression of HLA-DR and 4F2 molecules and the appearance of CD25 positive cells. CONCLUSIONS: Our results suggest that 31-43 and 44-55 A-gliadin peptides are both active, even if to different extents. In vitro systems remain essential tools to screen material to be subsequently tested in vivo.  相似文献   

9.
By mid-gestation (75-85 days, term=150 days), the ovine fetal adrenal gland is zoned into cortex and medulla. The cortex has an outer layer of cells which have the morphological characteristics of zona glomerulosa cells, containing mitochondria with lamellar cristae. It has been reported that cultured adrenal cells from mid-gestation bovine and ovine fetuses can be stimulated to increase aldosterone production, ten fold, by angiotensin II, and that this can be maintained for at least 3 days. However, the situation in vivo is unknown. In the current report we show that in chronically cannulated ovine fetuses at mid-gestation, angiotensin II (1 microg/h) does not increase aldosterone either in the short term (3 hours) or long term (3 days). However, ACTH (450 ng/h) can increase plasma aldosterone in the short but not long term. ACTH at this dose produces progressive and large increases in cortisol production. Angiotensin II is pressor and produces a modest diuresis without stimulating cortisol.  相似文献   

10.
11.
In vitro studies demonstrated a high degree of the rank correlation between the synthesis of cholera exotoxin and neuraminidase by cholera vibrios (V. cholerae 569B). The appearance of these biochemically-active materials proved to depend on the growth phase of the microbial population. A possibility of cooperation between them in the pathogenesis of cholera is suggested.  相似文献   

12.
Some properties of specific progestogen binding activity in the human cervix are described. High cytosol affinity was observed for progesterone and synthetic progestagens, but not for corticosteroids or norethindrone, medroxyprogesterone acetate, chlormadinone acetate, progesterone, 5alpha-pregnane-3,20-dione, norethindrone acetate, 17alpha-hydroxyprogesterone, cortisol, and estradiol. Progesterone binding in cytosols with high concentrations of CBG-like contaminants had a dissociation rate constant of 6.9 X 10(-5)s(-1). Ka values were similar for binding sites throughout the cervix, with concentrations being highest in the region around the columnar epithelium. Concentrations of binding sites per mg DNA were similar in the columnar epithelium and stroma, but higher in the squamous epithelium. Progesterone binding to endometrial tissue was greater than that for the corresponding cervix. Mean concentrations per mg were markedly higher during the proliferative phase than the secretory phase of the menstrual cycle, though this difference in terms of concentrations per mg DNA was significant only for cervical cytosols.  相似文献   

13.
14.
Granulosa cells of ovarian follicles both proliferate and undergo differentiation. In vivo, an inverse relationship between proliferation and steroidogenesis is observed. However, both processes can be enhanced by insulin-like growth factor-I (IGF-I) in vitro. Studies were undertaken in the ewe to understand the mechanisms controlling the balance between proliferation and differentiation in cultured granulosa cells from antral follicles better. For this purpose, granulosa cells from ovine small follicles (1-3 mm in diameter) and large follicles (5-7 mm in diameter) were compared for progesterone secretion, cytochrome P450 side-chain cleavage (P450scc) expression and their proportions of non-proliferating (G0) cells, in response to IGF-I and FSH stimulation in vitro. IGF-I mainly enhanced the proliferation of granulosa cells from small follicles but it strongly increased progesterone secretion and P450scc expression in granulosa cells from large follicles, in synergy with FSH. Blocking granulosa cell proliferation by the administration of colcemid or aphidicolin had no effect or a weak stimulating effect on progesterone secretion. At the beginning of the culture period, the proportion of non-proliferating cells, estimated by continuous [3H]thymidine labelling experiments, was clearly higher in large than in small follicles (91% vs 30%, P < 0.001). For both cell types, treatment with IGF-I in vitro reduced the proportion of non-proliferating cells at 72 h of culture (40% vs 70% respectively in IGF-I-stimulated and unstimulated cells from large follicles, P < 0.001, and 17% vs 30% respectively in IGF-I-stimulated and unstimulated cells from small follicles, P < 0.001). Treatment with FSH had no effect on the proportion of non-proliferating cells. As revealed by immunohistochemistry experiments, IGF-I, in synergy with FSH, clearly increased the percentage of cells expressing P450scc enzyme and the intensity of staining in granulosa cells from large follicles. Unexpectedly, heavily stained cells in mitosis were observed in IGF-I-stimulated cells from large follicles after 96 h of culture, suggesting that dividing cells might also produce progesterone. Overall, these results support the hypothesis that the growth-promoting and the cytodifferentiative effects of IGF-I are clearly distinct. Moreover, they suggest that uncoupling between proliferation and steroidogenesis may occur in cultured ovine granulosa cells. The loss of proliferative activity accompanying terminal follicular growth in vivo could be reversed in vitro. During terminal follicular growth in vivo, the existence of an active mechanism inhibiting granulosa cell proliferation, and unrelated to terminal differentiation, is therefore strongly suspected.  相似文献   

15.
The changes in the growth and differentiation of the cervical epithelium induced during pregnancy by hormonal influence and anatomical alterations are discussed regarding their magnitude on cervical oncogenesis. Question about the necessity of the self-sufficient centralized reporting of the pregnant women with precancer and cancer lesions is put on.  相似文献   

16.
BACKGROUND: Although the literature on increased physical fitness and psychological outcomes has grown large, a number of methodological limitations remain unaddressed. The present study was designed to address a number of these limitations while examining the short- and long-term psychological effects following completion of a 12-week aerobic fitness program using bicycle ergometry (and confirmed increases in fitness). METHOD: Following completion of a 12-week aerobic fitness program (and through 12 months of follow-up), 82 adult participants completed the Beck Depression Inventory, Profile of Mood States, State-Trait Anxiety Inventory, and the Tennessee Self-Concept Scale. Physiological measures used to assess changes in aerobic fitness were maximal work load, submaximal heart rate at a standard work load, predicted maximum oxygen uptake, and resting heart rate. RESULTS: Exercise participants experienced a positive fitness change and psychological improvement over the initial 12-week program compared to a control group. At 1 year follow-up, physiological and psychological benefits remained significantly improved from baseline. CONCLUSIONS: Overall, results indicate that exercise-induced increases in aerobic fitness have beneficial short-term and long-term effects on psychological outcomes. We postulate that participants in the exercise group did not increase the amount of weekly exercise they performed over the 12-month follow-up period and thus the maintenance of the psychological improvements occurred concurrent with equal or lesser amounts of exercise.  相似文献   

17.
Treatment of pregnancy toxaemia in ewes by induction of parturition is reported. The efficacy of 3 formulations of dexamethasone, at different dosages, is recorded and discussed.  相似文献   

18.
OBJECTIVES: Uterine quiescence during mammalian pregnancy is attributed to progesterone. However. systemic progesterone levels remain elevated in primates before parturition. Epostane, a selective 3beta-hydroxysteroid dehydrogenase inhibitor, and progesterone (with or without epostane) were administered to late pregnant rhesus monkeys to clarify the role of progesterone in primate parturition. STUDY DESIGN: On days 122 to 132 of gestation (term 167 days), 11 rhesus monkeys (Macaca mulatta) with timed pregnancies were divided into three treatment groups: (1) epostane alone (10 mg/kg subcutaneously), (2) epostane with progesterone subcutaneously in Silastic silicone rubber capsules, and (3) progesterone implants only with no surgical instrumentation. Maternal and fetal blood and amniotic fluid were sampled for progesterone, estrone, estradiol, cortisol, testosterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and amniotic fluid was sampled for prostaglandins E2 and F2alpha. Uterine activity was monitored continuously by electromyography and intraamniotic pressure. Cervical status was assessed by a modified Bishop's score. Production of prostaglandins E2 and F2alpha by amnion was determined by tissue superfusion. The group of three noninstrumented monkeys, which received only progesterone Silastic silicone rubber implants subcutaneously at 146 to 148 days, were observed until spontaneous vaginal delivery. RESULTS: Epostane reduced maternal and fetal progesterone levels by 75% and 50%, respectively, followed by increased uterine activity and cervical ripening within 24 hours and vaginal delivery within 48 hours. Amniotic fluid progesterone decreased to undetectable levels. Progesterone implants prevented the epostane-induced decrease in maternal and fetal progesterone levels and the associated myometrial and cervical changes until the implants were removed. Alterations in other steroid hormones were consistent with inhibition of 3beta-hydroxysteroid dehydrogenase. Amniotic prostaglandin E2 production was increased sixfold by epostane (p < 0.05) but did not reach the high levels normally seen at spontaneous parturition. Animals that received progesterone implants alone had markedly elevated circulating progesterone concentrations yet were delivered spontaneously at term (range 163 to 167 days). CONCLUSIONS: Progesterone withdrawal induces preterm labor and delivery (which can be blocked by progesterone substitution) but exogenous progesterone, even in substantial quantities, does not prevent parturition at term.  相似文献   

19.
A retrospective study has been made of 15 patients who had developed severe complications to the bladder, rectum and ureters after radiation therapy for carcinoma of the cervix. Comprehensive dose distribution in the pelvis were calculated with computer assistance to visualize how the normal organs had been irradiated. The risk of normal tissue injury was analysed graphically with respect to the maximum radium dose, dose-rate and irradiation time. The two groups of data representing the injured and non-injured organs separate much better in a dose-rate versus dose plot than in a conventional Strandqvist type dose-time plot. This implies that in radium therapy, the dose-rate rather than the treatment time, is the important parameter in modifying the risk of normal tissue injury. Our results show a good separation of injured from non-injured cases only when the maximum values of dose and dose-rate were used. This suggests that clinically significant injury may develop from relatively small regions of high dose and dose-rate. Since the dose-rate varies from point to point in the pelvis (unlike treatment time), comprehensive determinations of dose-rate distributions are required in order to locate the sites of potential injuries.  相似文献   

20.
We have investigated the toxicity of dose-escalation of BCNU, etoposide and melphalan ('BEM') chemotherapy with autologous stem cell transplantation in patients with haematological malignancies. Seventy-two patients with haematological malignancies were treated with BCNU (600 mg/m2, 450 mg/m2 or 300 mg/m2), etoposide 2 g/m2 and melphalan 140 mg/m2 followed by autologous bone marrow transplantation (ABMT), n = 51, or autologous peripheral blood progenitor cell transplantation (APBPCT), n = 21. Liver and pulmonary function was monitored pretransplant and at regular intervals post-transplant. Mucositis was graded daily during in-patient stay. There was a significantly higher incidence of symptomatic pulmonary toxicity in the patients who received BCNU at 600 mg/m2 than in the other two groups, and there was a significant increase in the incidence of asymptomatic decrease in carbon monoxide (KCO) in the patients who received BCNU 450 mg/m2. There was no significant difference between the three groups in the incidence and severity of mucositis or in the incidence of transiently abnormal liver function. We conclude that etoposide at 2 g/m2 can be used without unacceptable mucositis. BCNU at 600 mg/m2 is associated with an unacceptably high incidence of lung toxicity, but at 450 mg/m2 there is minimal symptomatic lung toxicity.  相似文献   

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