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1.
To study the human genetic damage induced by vincristine (VCR), the cytogenetic effects in workers occupationally exposed to vincristine were studied with micronucleus (MN) test, comet assay, hypoxantinepho-guanine phosphoribosyl-transferase (hprt) gene mutation assay and T-cells receptor (TCR) gene mutation assay. Fresh peripheral blood samples were collected from the workers and controls. Fifteen workers from a plant producing antineoplastic drug (vincristine) and 15 controls were matched according to age, gender and smoking. The results of MN test showed that the mean micronuclei rate (MNR) and mean micronucleated cells rate (MCR) in 15 workers were 17.80+/-1.88 per thousand and 13.67+/-1.56 per thousand, respectively, which were significantly higher than those (3.73+/-0.80 per thousand and 3.13+/-0.59 per thousand) in controls (P<0.01). It was found in the comet assay that the mean tail length (MTL) of 15 workers and 15 controls were 1.72+/-0.15 microm and 0.71+/-0.01 microm, respectively, there was significant difference between workers and controls for MTL (P<0.05), but the difference between the mean tail moment (MTM, 0.29+/-0.03) of 15 workers and MTM (0.17+/-0.05) of 15 controls was not significant (P>0.05). The results of hprt gene mutation assay showed that the average mutation frequency of hprt (Mf-hprt) in workers was 1.03+/-0.02 per thousand, which was significantly higher than that (0.87+/-0.01 per thousand) in controls (P<0.05). Meanwhile, the results of TCR gene mutation assay indicated that Mfs-TCR of workers and controls were 2.52+/-0.34 x 10(-4) and 1.51+/-0.11 x 10(-4), respectively, there was a significant difference between workers and controls (P<0.01). It is found in the results of our study that the genetic damage is detectable in 15 workers occupationally exposed to vincristine.  相似文献   

2.
Recently, biochemical studies of paraoxonase in the serum of humans have shown that much of this enzymes' activity is associated with high-density lipoprotein (HDL) and paraoxonase may play a role in lipid metabolism preventing the accumulation of the lipoperoxides. In this study, a possible relationship between coronary heart disease (CHD) and paraoxonase activity were investigated. Serum triglycerides, total cholesterol, HDL-cholesterol and paraoxonase activity were measured in unrelated healthy donors and CHD patients. It was found that paraoxonase activity was trimodally distributed in both groups but no statistically significant difference was found between phenotype distributions of controls and CHD patients (gene frequencies; 0.632 and 0.382 of controls, 0.702 and 0.298 of patients for the A and B alleles, respectively). However, in CHD group, a high possibility was found to be phenotype A compared with the control group. A relative risk of 1.48 (95% confidence intervals (CI), 0.986-2.227) was found for the relation between CHD and the paraoxonase activity. Patients' HDL-cholesterol values were lower and triglycerides were higher than controls (P<0.001). It may be concluded from the present study that although no statistically significant difference was found between paraoxonase phenotype distributions of controls and CHD patients, a decrease in paraoxonase activity could become a risk factor for this disease.  相似文献   

3.
Gall-bladder emptying in response to a standard meal was assessed in 34 patients with radiolucent gall stones and 34 matched controls. Percentage gall-bladder emptying, derived from volume measurements made on standardised oral cholecystography, was significantly higher at 15 minutes in the patients than the controls (mean +/- SE of mean 38.0 +/- 3.7% v 28.0 +/- 3.8%). This difference was maintained at 30 and 60 minutes. It is concluded that postprandial gall-bladder emptying is increased in patients with cholesterol gall stones, and that this may be the cause of the small bile-acid pool found in these patients.  相似文献   

4.
Howard Reed  Shirley Platts 《CMAJ》1964,90(24):1352-1353
The blood of patients suffering from cataracts, glaucoma and strabismus was grouped and the distribution of their blood groups was compared with that of blood groups in volunteers at blood donor clinics. It was found that there was no significant difference between the distribution of groups among these patients and that among the controls.  相似文献   

5.
Aluminium-transferrin (Al-Tf) and gallium-transferrin caused a dose-dependent decrease in proliferation of human peripheral blood lymphocytes cultured for 3 days with phytohaemagglutinin (PHA). Addition of apotransferrin reduced the inhibitory effect. Al added as AlCl3 or aluminium citrate had no effect, and there was no significant difference in the response of cells from renal failure patients with or without high serum Al levels or controls. Lymphocytes cultured in the presence of Al-Tf showed a dose-dependent uptake of Al, whereas uptake from aluminium citrate was low and not dose-dependent. Uptake from AlCl3 was very high but probably involved a nonspecific uptake mechanism. Levels of Al in freshly isolated lymphocytes were approximately 1.6 ng/10(6) cells, there being no difference between cells from patients and controls. It is concluded that Al, when bound to transferrin, may have a detrimental effect on lymphocyte function and might contribute to the decreased immune responsiveness of renal failure patients on haemodialysis. However, lymphocyte Al levels are probably not useful as a marker of Al overload in such patients.  相似文献   

6.
Using a lucigenin-dependent chemiluminescence the authors have measured the "respiratory burst" in polymorphonuclear cells from psoriatic patients and controls. Measurements were performed under stimulation with zymosan, phorbol 12-myristate 13-acetate and latex beads. It has been revealed that the response after stimulation with zymosan increased although there was no significant difference between patients and controls, while the response after stimulation with phorbol 12-myristate 13-acetate and latex beads was significantly increased. Our results suggest an enhanced metabolic activity of polymorphonuclear cells induced by stimuli acting independently from cell-membrane receptors. Therefore an enhanced excitability of polymorphonuclear leukocytes of psoriatic patients is supposed.  相似文献   

7.
Following the observation detected in a previous study that X chromosome monosomy in Turner's syndrome genotypes was associated with a sporadic loss and/or gain of other chromosomes, we studied here whether this instability is a consistent finding in constitutional autosomal trisomies. We used PHA-stimulated lymphocytes derived from 14 patients (10 patients with trisomy 21, 2 with trisomy 18, and 2 with trisomy 13). Fourteen healthy controls were compared. Fluorescence in situ hybridization, applied at interphase cells, was used to evaluate the level of aneuploidy for 3 randomly selected chromosomes (autosomes 8, 15, and 16) in each sample. For each tested chromosome, our results showed a significantly higher level of aneuploid cells in the samples from the patients than in those from controls, with no difference between the patient groups. The mean level of aneuploid cells (percentage) for all 3 tested autosomes was almost twice as high in the patient samples as in the control samples. The aneuploidy level was mainly due to monosomy, which was significantly higher in the samples from the patients than in those from controls for each one of the tested chromosomes, with no difference between the patient groups. The mean level of monosomic cells (percentage) for all 3 tested chromosomes was almost twice as high in the patient samples as in the control samples. Our study shows that various constitutional autosomal trisomies are associated with an increased frequency of non-chromosome specific aneuploidy and is a continuation of the previous study documenting sporadic aneuploidy in Turner's sample cells. It is possible that primary aneuploid cells destabilize their own genome resulting in variable aneuploidy of other chromosomes. It is also possible that one or several common factor(s) is/are involved in both constitutional and sporadic aneuploidy.  相似文献   

8.
Fingerprints of 570 breast cancer cases and the same number of matched controls were obtained from the population-based finger print file in Hawaii for studying the association between breast cancer and digital dermal patterns and ridge counts. The results showed that breast cancer patients had a significant excess of radial loops on the left hand. It was also found that the frequency of ulnar loops on the left hand was significantly elevated for premenopausal women with breast cancer, whereas an excess of radial loops on the left hand was observed for the postmenopausal women with breast cancer. No significant difference for the total and absolute ridge counts was found between breast cancer patients and controls.  相似文献   

9.
The formation of leukotriene B4 and its omega-oxidised metabolites has been compared in calcium ionophore-stimulated polymorphonuclear leukocytes, in the absence of exogenous substrate, from fourteen psoriatic subjects and thirteen healthy controls. Although there was no significant difference in the levels of leukotriene B4, the psoriatic cells synthesised significantly greater amounts of omega-oxidation products than control cells. This difference was confirmed in an experiment comparing the time course of formation of the omega-oxidation products of leukotriene B4, under similar conditions, in polymorphonuclear leukocytes from four psoriatic subjects and three healthy controls. The kinetic constants for the metabolism of exogenous leukotriene B4 by 20-hydroxylase were determined by a radiochromatographic enzyme assay in polymorphonuclear leukocytes from three patients with psoriasis and three healthy controls. No significant differences were found in the apparent Km and Vmax values. It is concluded that the increased formation of omega-oxidation products in psoriatic cells may be secondary to increased synthesis of leukotriene B4 by these cells, with consequent increased metabolism, rather than to an inherent abnormality of the 20-hydroxylase system. Further work is needed to determine the kinetics of the enzymes involved in leukotriene B4 synthesis in the psoriatic polymorphonuclear leukocyte, and also to assess the contribution of the leukotriene B4 and omega-oxidation products from polymorphonuclear leukocytes infiltrating the skin to the pathogenesis of the psoriatic lesion.  相似文献   

10.
Erythrocytes delta-aminolevulinate dehydratase activity was assayed in 41 diabetic patients and 33 normal controls. It was found that in diabetic patients the erythrocyte ALA-D activity was lower than in controls, and the difference of the mean values was statistically highly significant (P less than 0.001). We found a significant negative correlation (r = - 0.846, P less than 0.001) between ALA-D activity and blood glucose levels. For this reason, using normal adult human whole blood haemolysates, it was investigated the effects in vitro of glucose and insulin on normal erythrocytic ALA-D. No significant difference in ALA-D activity was found in the presence of insulin. On the other hand, there was considerable decrease in the enzyme activity in the blood samples after glucose addition.  相似文献   

11.
Gastrointestinal symptoms in diabetic patients are commonplace, and are believed to be due, at least partly, to neuropathy of the gut. In the present study, therefore, some important neurotransmitters in the myenteric plexus were investigated in non-obese diabetic mice, an animal model of human type 1 diabetes. For this purpose, immunocytochemistry was applied on sections from antrum, duodenum and colon, subsequently quantified by computerized image analysis. Whereas the number of vasoactive intestinal peptide (VIP)-positive neurons was increased in antral myenteric ganglia of diabetic mice, there was a decreased density of nerve fibres in muscularis propria. No difference was seen in the VIP of duodenum and colon. Acetylcholine-containing nerve fibres showed an increased volume density in muscularis propria of antrum and duodenum, but a decreased density in colon of diabetic mice, as compared with controls. There was a decreased number of neurons containing nitric oxide synthase (NOS) in myenteric ganglia of antrum and duodenum. No difference was seen in density of NOS-containing nerve fibres in muscularis propria. There was no difference regarding neuropeptide Y (NPY) and galanin between diabetic and control mice; nor was there any difference between pre-diabetic NOD mice and controls regarding all bioactive substances investigated. It is concluded that the diabetic state affects the innervation of gut in this animal model. The present findings may be of some relevance to the gastrointestinal symptoms seen in patients with diabetes.  相似文献   

12.
Nyssa sylvatica seedlings grown for a year under flooded conditions established endomycorrhizal associations with Glomus mosseae. Lowland ecotypes with endomycorrhizae showed a significant increase in biomass over non-mycorrhizal controls; the greatest difference was in aboveground biomass. Upland ecotypes survived flooding poorly and established fewer endomycorrhizae than lowland ecotypes and did not show any enhanced growth over controls. In general, most endomycorrhizae were formed near main roots and significantly decreased in abundance with distance from the main axes of the root system. It is suggested that under flooded conditions internal oxygen transport may be limiting to mycorrhizae in the more distal roots.  相似文献   

13.
The authors have performed an international case-control study on the significance of exogenous hormones for the origin of hypospadias (K?llén et al., 1991 a,b). Using data from this study on 846 infants with isolated hypospadias and equally many controls (next male infant born in the same hospital as the case), variables that might indicate an increased rate of fertility problems in couples who had a boy with hypospadias were studied. Cases had slightly fewer previous pregnancies, there was practically no difference in the rate of previous induced abortions, and no demonstrable difference in menstrual history. Infertility periods of at least 6 months were more likely among cases than controls but the difference did not reach statistical significance in a two-tailed test. There was no demonstrable difference in the time to conceive between cases and controls. The difficulties of directly studying subfertility problems are stressed.  相似文献   

14.
Recent reports have indicated that genetically obese hyperinsulinemic mice (ob/ob) and Zucker rats (fa/fa) compared with their lean controls have elevated levels of pituitary and plasma B-endorphins, opiates that can stimulate insulin secretion. In this study we have measured opiate levels by a radio-receptor assay in gastro-intestinal tissues and pancreas in ob/ob and fa/fa animals and their controls. Ob/ob mice showed significantly higher levels than control mice (+/+) in most gastro-intestinal tissues and pancreas. Levels in fa/fa rats did not differ from their controls. Radioimmunoassay of pancreas for B-endorphins, revealed higher levels in ob/ob vs +/+ mice, while there was no difference in the obese and lean rats. Fasting tended to decrease gastro-intestinal opioids in mice, while B-endorphin levels rose. It is concluded that opiates may play a significant role in the obesity of the ob/ob mouse and that this genetic obesity differs from that in Zucker rats.  相似文献   

15.
The effect of lanthanum ions (La3+) on the release of acetylcholine (ACh) from longitudinal muscle strips of the guinea pig ileum with the myenteric plexus attached was investigated. After an exposure of the tissue to 2 mM LaCl3 for 18 min the rate of ACh release was increased approximately eightfold and the increased release lasted for more than 100 min. The augmented release of ACh was accompanied by enhanced synthesis. At the end of the experiments (102 min after LaCl3 had been removed), when the release of ACh was still more than six times higher than in controls, the content of ACh was the same in La3+-treated and untreated tissues. Electrical field stimulation failed to cause a further increase in the release of ACh from La3+-pretreated preparations whereas ouabain released considerable more ACh when compared to controls. It is concluded from this difference that electrical stimulation and ouabain release ACh from different pools.  相似文献   

16.
Haptoglobin and transferrin types were studied in schizophrenic patients and controls. In the haptoglobin system a significant departure from the Hardy-Weinberg equilibrium with an excess of heterozygotes was found among the patients (p less than 0.01). The distribution of haptoglobin types in the schizophrenic patients was significantly different from that in the controls. The distribution of transferrin types showed a good agreement with the Hardy-Weinberg equilibrium. There was no significant difference between patients and controls with respect to transferrin types.  相似文献   

17.
The effect of physical training on hemodynamic performance was evaluated in a group of patients who had had a myocardial infarction and a group of healthy, age-matched controls. Before training, the patients'' mean ventilatory equivalent was significantly less than that of the controls at the lowest workload (300 kpm/min), the mean stroke volume was significantly increased at the highest workload then achieved (600 kpm/min), and the mean arteriovenous oxygen content difference was significantly smaller at the highest workload. The patients had a relative bradycardia before training and there was no significant reduction in mean resting or submaximal heart rate after training. Their mean oxygen uptake was significantly reduced at the lowest exercise workload after training and this response was significantly different from that of the controls after 8 weeks of training. Mean cardiac output during exercise was significantly reduced in the patients after training, but only at the 600-kpm/min workload, the response being blunted at 900 kpm/min; mean stroke volume was also significantly reduced at this workload after training; both these responses were significantly different from those of the controls Mean arteriovenous oxygen content difference at 6oo kpm/min was significantly increased in the patients after training, though the response was not significantly different from that of the controls. Mean ventilatory equivalent was also significantly increased in patients after training, becoming similar to that of the controls.  相似文献   

18.
Prostaglandin E2 (PGE2) was tested for its ability to produce a positive chronotropic and inotropic response on isolated atria obtained from normal (NWR) and spontaneously hypertensive rats (SHR). There was no significant difference in the basal in vitro heart rate of atria from NWR and SHR. There was no significant difference in the increase in heart rate or contractile force produced by PGE2 (0.568 μM and 5.68 μM) on atria obtained from NWR compared to SHR. It appears there is no difference in the in vitro cardiac reactivity to PGE2 of atrial tissue from SHR compared to normotensive controls under the conditions of these experiments. This is in contrast to the previously reported decrease in contractile responses of atrial tissue of SHR to certain cardiac stimulants, and the diminished contractile response produced by PGE2 on arterial tissue from SHR compared to NWR.  相似文献   

19.
We have measured activity of platelet-activating factor (PAF) acetylhydrolase, an enzyme that specifically inactivates PAF, in plasma from patients with essential hypertension and healthy controls. The average activities in 34 patients and 22 controls were 113 +/- 60 and 79 +/- 32 nmol/ml/min, respectively, and the difference was significant (p less than 0.05). Approximately three fourths of the total plasma activity was recovered in LDL, with the remainder in HDL; and there was a significant difference in the activity associated with the LDL between patients and controls. The relative distribution of the activity among lipoproteins was almost equal in the two groups, and there was no difference in plasma lipids or apoproteins between them. In patients there was a tendency for plasma PAF acetylhydrolase activity to increase with the length of the history of hypertension. Further studies are needed to distinguish between a number of reasons for increased levels of plasma PAF acetylhydrolase in essential hypertension.  相似文献   

20.
Fourteen gilts were aborted (some of them repeatedly) by i.m. administration of 500/ug cloprostenol (PG) between 30 and 100 days of pregnancy so that the total number of PG-induced abortions was 19. Six of these gilts were allowed to terminate their subsequent pregnancy by farrowing. It was found that In a Trial under semi-production conditions the mean birth body mass of piglets from 11 gilts bred after previous PG-induced abortion was 1.48 kg as compared to 1.19 kg in the controls. The difference was significant (P<0.01).  相似文献   

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