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1.
OBJECTIVE: To determine the efficiency of in vitro maturation, expressed by nuclear maturation, of oocytes aspirated during gynecologic surgeries or collected from excised ovaries. To assess the effect of patient age and cycle phase at collection on the oocyte's ability to mature in vitro. To examine the time course of oocyte maturation in vitro. DESIGN: Nuclear maturation based on patient criteria compared. SETTING: University-based IVF program and research center. PATIENT(S): Consented patients undergoing gynecologic surgeries or patients undergoing oophorectomy. INTERVENTION(S): Oocytes were maintained in culture for 48 hours and evaluated for maturation. MAIN OUTCOME MEASURE(S): Nuclear maturation evaluated as germinal vesicle breakdown (GVBD) or progression to the metaphase II (MII) stage. RESULT(S): A significantly higher percentage of oocytes collected during the follicular phase of the menstrual cycle underwent GVBD than did oocytes collected during the luteal phase (60% versus 48%, respectively). The percentage of oocytes reaching the MII stage, from these two groups, was not different. No statistically significant differences in maturation were observed in oocytes from different ovarian sources or from patients >40 or <40 years of age. CONCLUSION(S): These data suggest that oocytes collected during the follicular phase are more likely to undergo GVBD than oocytes collected during the luteal phase. In this study, ovarian source, age, or cycle phase did not influence the final meiotic maturation of oocytes to metaphase II.  相似文献   

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Wisconsin Card Sorting Test (WCST) performance was assessed in 24 heavy smokers and 12 nonsmokers recruited from universities in the US and Japan. Half of the smokers performed the WCST after abstaining from tobacco for 12 hrs, whereas the remaining smokers smoked a cigarette of their preferred brand immediately before the test. Nonsmokers did not smoke. The WCST was administered by computer, first with standard instructions and then a 2nd time with abbreviated instructions that specified the 3 sorting criteria. Results from the 2nd run indicated that abstinent smokers made significantly more perseverative responses and errors than did nonsmokers or smoking smokers. Results expand on previous findings of effects of smoking deprivation on human cognitive performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Levels of plasma vitamin C and E (P-VC, P-VE), beta-carotene (P-beta-Car), lipoperoxides (P-LPO), and activity of erythrocyte superoxide dismutase (E-SOD) were measured in 871 healthy smokers and 348 healthy non-smokers to study the relationship between cigarette smoking and antioxidant vitamins and oxygen free radicals. Results showed that levels of P-VC, P-VE, P-beta-Car and E-SOD reduced significantly, and level of P-LPO increased significantly in smokers, as compared with those in non-smokers. Levels of P-VC, P-VE, P-beta-Car and E-SOD reduced and level of P-LPO increased in 65 male smokers at the same age, with the increase of duration of smoking and quantity of cigarettes smoked, showing a linear correlationship. It suggested that there existed serious imbalance between oxidation and antioxidation in the bodies of smokers, and oxygen free radical reaction and reaction of lipoperoxidation obviously intensified.  相似文献   

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The effects of cigarette smoking on pain perception were evaluated in 18 healthy smokers. Thermal pain stimuli were used to assess pain detection threshold and tolerance and to collect subjective ratings of the intensity and unpleasantness of painful stimuli. After overnight abstinence, pain perception was evaluated before and after 3 experimental treatments. Participants smoked normal cigarettes, smoked denicotinized cigarettes, or remained abstinent. Smoking normal cigarettes produced relative increases in pain tolerance compared with abstinence. Smoking denicotinized cigarettes produced intermediate effects on tolerance not different from the other 2 treatments. Effects were not detected for pain threshold or subjective pain ratings. Results suggest that cigarette smoking can have antinociceptive effects, which may depend both on nicotine and on other factors associated with smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The authors of this study examined the effects of brief smoking abstinence on smoking among 6 individuals with schizophrenia or schizoaffective disorder. Before 6 of 12 experimental sessions, participants were required to provide breath carbon monoxide (CO) samples indicative of smoking abstinence; before the remaining sessions, participants provided CO samples indicating no abstinence. During sessions, participants obtained smoking opportunities (2 puffs/opportunity) under either fixed ratio-1 or progressive ratio (PR) schedules of reinforcement. Abstinence increased smoking under both schedules and increased breakpoint for smoking under the PR schedule. These data offer further evidence that smoking by individuals with schizophrenia is orderly, operant behavior that is modulated, at least in part, by variables that also affect smoking in people without major mental illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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BACKGROUND: The acute effects of cigarette smoking on gastric emptying are controversial, whereas its effects on the intragastric distribution of solids and liquids are not established. METHODS: Dual isotope gastric scintigraphy was performed in 15 habitual smokers (studied twice, either sham smoking or actively smoking) and in 15 age- and sex-matched nonsmokers. RESULTS: Acute smoking was associated with an increased prevalence of episodes of retrograde intragastric movement of solids (3 of 15 sham subjects vs. 12 of 15 actively smoking subjects; P < 0.01) and of liquids (0 of 15 vs. 7 of 15; P < 0.01) from distal to proximal stomach. Fundal half-emptying time (T1/2) for liquids was also prolonged by smoking (43 +/- 19 minutes sham vs. 125 +/- 216 minutes active; P < 0.05). Acute smoking delayed solid lag time (13 +/- 6 minutes sham vs. 32 +/- 18 active; P < 0.05) and liquid T1/2 (46 +/- 21 vs. 90 +/- 50 minutes; P < 0.05). In the nonsmokers, such episodes of proximal intragastric redistribution did not occur, and intragastric and overall emptying parameters did not differ significantly from those of habitual sham smokers. CONCLUSIONS: Acute cigarette smoking produces excessive antrofundal redistribution of both solid and liquid contents and delays solid and liquid gastric emptying.  相似文献   

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In this study, the authors investigated the effects of the indirect dopamine agonist d-amphetamine (AMPH) on cue-induced cigarette craving in smokers. Abstinent or nonabstinent cigarette smokers (N=21) rated their cravings for cigarettes and for food (control) after pretreatment with AMPH (15 mg) or placebo and before and after viewing blocks of smoking-related, food-related, and neutral pictures. Before the cues were presented, AMPH increased cigarette craving and decreased food craving. Smoking and food cues increased craving for cigarettes and for food, respectively. AMPH also further increased cigarette craving (and decreased food craving) after cue presentation, but it did so regardless of cue type (food or smoking). Smoking abstinence markedly increased craving regardless of cue presentation or drug condition. These results suggest that both AMPH and smoking abstinence can increase cigarette craving, but they do not appear to specifically affect responses to conditioned smoking-related cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Adverse influence of cigarette smoking on the endothelium   总被引:2,自引:0,他引:2  
The effect of smoking on the blood vessel intima was examined by comparing indices of endothelial activity in serum from smokers with that from non-smokers. Serum from smokers contained higher levels of von Willebrand factor (p < 0.01), the smoking markers cotinine (p < 0.02) and thiocyanate (p < 0.01), and was more cytotoxic to endothelial cells in vitro (p < 0.02) than serum from non-smokers. The acute effects of smoking two unfiltered medium tar cigarettes was to briefly increase von Willebrand factor (p < 0.001) and cytotoxicity of serum to endothelial cells in vitro (p < 0.005), but lipid peroxides or thiocyanate were not increased by this short exposure to tobacco smoke. Although there were correlations between von Willebrand factor and smokers consumption of cigarettes (r = 0.28, p < 0.02), number of years smoking (r = 0.41, p < 0.001) and cotinine (r = 0.45, p < 0.01), the tissue culture of endothelial cells with physiological levels of thiocyanate or nicotine suggested that these two smoking markers were not cytotoxic. They are therefore unlikely to be directly responsible for increased von Willebrand factor in the serum of smokers. We suggest that smoking exerts a deleterious influence on the endothelium and that the mechanism is complex.  相似文献   

10.
The effects of acute cigarette smoking on endothelial function were evaluated in the brachial artery of 10 nonsmoking healthy subjects. Endothelial dysfunction observed after cigarette smoking is a phenomenon lasting at least 60 minutes and does not appear to be attenuated with repeat exposure.  相似文献   

11.
Neisseria lactamica was isolated from the blood of a pediatric patient who had signs of septicemia and otitis media. Organisms morphologically resembling Neisseria, as well as gram-positive cocci, were seen on a Gram stain of fluid from the middle ear. It is hypothesized that the N. lactamica septicemia was secondary to infection of the middle ear by this organism.  相似文献   

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Sperm-induced Ca2+ signals mediate the events of oocyte activation at fertilization. In this study, the development of mechanisms involved in the generation of Ca2+ signals in human oocytes was investigated. The thiol reagent, thimerosal, which induces oscillations of intracellular Ca2+ ([Ca2+]i) similar to those seen during fertilization, was used to mobilize Ca2+ in in-vivo matured, immature and in-vitro matured human oocytes. There was an increase in the sensitivity to thimerosal during maturation of human oocytes, with oocytes from small antral follicles being relatively insensitive, compared with those from luteinized follicles, which displayed a large spike followed by sustained oscillations in [Ca2+]i. These oscillations were inhibited by caffeine which suggests that they were mediated by the inositol trisphosphate receptor Ca2+ release system. When immature oocytes were cultured in vitro they acquired the capacity to undergo a single large spike in [Ca2+]i, however, subsequent sustained oscillations were not observed, indicating that these oocytes failed to develop fully competent Ca2+ signalling mechanisms during culture in vitro. This finding may be a key factor in the poor developmental competence of in-vitro matured human oocytes.  相似文献   

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Skin conductance responses (SCRs) evoked by novel, signal, and frequent tone stimuli were measured in 20 male heavy smokers and 10 male nonsmokers over two sessions. All smokers abstained from smoking for 12 hr prior to each session. Half of the smokers smoked a cigarette of their preferred brand prior to SCR measurement in the first session, whereas the remaining smokers smoked in the second session. Nonsmokers did not smoke. Results combined across the two sessions indicated that abstinence was associated with selective depression of SCRs to the novel tone. Separate analyses of results from each session revealed that, in the second session, SCRs to both novel and signal tones were depressed in abstinent smokers, partially replicating previous findings. By contrast, first session results showed no significant effects of smoking or abstinence. Results were interpreted in terms of nicotine's effects on nonspecific arousal, with some reservations.  相似文献   

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Investigated the measurement of alveolar carbon monoxide (CO) levels to validate self-reported smoking rates at the end of treatment. 127 volunteer smokers, mostly middle-aged, who were in behavioral smoking-cessation clinics were randomly assigned to 1 of 3 conditions that varied in timing of exposure to information regarding CO measurement: (a) at the beginning of treatment (demonstration of CO measurement, discussion of smoking effects on CO levels, and notification that individual CO levels would be measured at the conclusion of the clinic); (b) at the end of treatment (demonstration, discussion, and notification of CO measurement prior to self-reports of smoking levels); or (c) at the end of treatment (demonstration and discussion of CO measurement subsequent to self-reports of smoking levels). Only 16% of self-reports of abstinence were not verified by CO measurement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
The incidence of certain ageing sequelae such as lung and cardiovascular disease and cataract are higher in smokers than in non-smokers. We recently proposed that certain components of mainstream cigarette smoke can react with plasma and extracellular matrix proteins to form covalent adducts with many of the properties of advanced glycation endproducts (AGE). AGEs have been implicated previously in the pathogenesis of the end-organ complications of diabetes and ageing, including cataract, atherosclerosis and renal insufficiency. In these circumstances, AGEs arise in vivo from the non-enzymatic reaction of reducing sugars with amino groups. Over time the initial Schiff base and Amadori products that form gradually undergo dehydration and rearrangement to produce reactive, carbonyl containing compounds with characteristic fluorescence and covalent crosslinking properties. Recent studies indicate that in smokers, tobacco-derived AGEs accumulate on plasma low density lipoprotein (LDL), structural proteins present within the vascular wall, and the lens proteins of the eye. These data point to a new and significant source of Maillard products in the human environment, significantly broaden the role of Maillard chemistry in pathological processes, and provide new insight into the pathogenesis of atherosclerosis and other diseases associated with tobacco usage.  相似文献   

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Tested the effects of commitment (CM) to nonsmoking on resistance to arguments favoring cigarette smoking. In Exp I, 37 7th graders were assigned to a public CM condition, in which they were audiotaped as they explained why they would not become smokers, or to information control or no-treatment conditions. In Exp II, 51 7th graders participated in conditions of (1) high CM, in which they were given high choice to write and publicly audiotape a speech about why smoking is bad; (2) low CM, in which they were given low choice to write an anonymous essay about why smoking is bad; or to (3) a no-treatment condition. Ss then listened to arguments favoring smoking. CM failed to enhance resistance to persuasion in either experiment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
To determine the relative effects of expectancy and nicotine depletion on aversive withdrawal symptoms, we gave 109 smokers attempting to quit either nicotine gum or placebo within a balanced placebo design and monitored their withdrawal symptoms and smoking for 2 weeks. Subjects who believed they were getting nicotine gum reported less physical symptoms of withdrawal, showed less arousal, and smoked fewer cigarettes during the first week of quitting when compared with those who thought they were receiving placebo gum. The actual nicotine content of gum had no effect on withdrawal or relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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