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排序方式: 共有1165条查询结果,搜索用时 78 毫秒
1.
Angiotensin Converting Enzyme Inhibitors: Animal Experiments Suggest a New Pharmacological Treatment for Alcohol Abuse in Humans 总被引:1,自引:0,他引:1
G. Spinosa MSc E. Perlanski Dipl Tech. F. H. H. Leenen MD R. B. Stewart MSc L. A. Grupp DSc 《Alcoholism, clinical and experimental research》1988,12(1):65-70
The prevalence of heavy alcohol consumption is a major problem of increasing proportions throughout the world. Although alcohol sensitizing drugs and more recently serotonin uptake inhibitors are drug interventions with some following, their long term beneficial consequences have yet to be demonstrated. In recent years, we have demonstrated that manipulating activity in the renin-angiotensin system will dramatically alter voluntary alcohol consumption in rats. Based on these findings, the present study evaluated the ability of a class of drugs known as the angiotensin converting enzyme inhibitors to reduce voluntary alcohol drinking in laboratory animals. These drugs prevent the conversion of angiotensin I to angiotensin II. They have been licensed for use in Europe and North America and are indicated in the treatment of hypertension. Our experiments showed that both captopril (Capoten, Squibb) and enalapril (Vasotec, Merck Sharpe & Dohme) can reduce alcohol drinking in both normotensive and hypertensive animals regardless of whether the pattern of intake is in a bout or of a less exaggerated nature. Furthermore, this change in alcohol intake can occur without concomitant changes in blood pressure, plasma renin activity, overall fluid balance, or the distribution and metabolism of alcohol. Taken together these findings suggest that the angiotensin converting enzyme inhibitors should be evaluated in a clinical setting for they may prove to be a useful new treatment or treatment adjunct for alcohol abuse in humans. 相似文献
2.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
3.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
4.
The present study is aimed at an electron-microscopic morphometrical analysis of the pyramidal tract of 14-month-old rats at the level of the pyramis medullae and the second cervical segment, and a comparison with data obtained for rats of two months of age. Between 2 and 14 months of age there is, at the level of the pyramis medullae of the left pyramidal tract, a statistically significant increase of the number of myelinated fibers, from 91,000 to 118,000, whereas the total number of unmyelinated fibers decreases from 133,000 to 101,000. On the right side at the same level there is no statistically significant change in the number of myelinated fibers, whereas there is a significant decrease of unmyelinated fibers at this side, from 148,000 to 89,000. At the second cervical level, a statistically significant increase in the number of myelinated fibers has been noted at both sides (from 43,000 to 60,000) between 2 and 14 months, whereas the mean total number of unmyelinated fibers at this level decreases somewhat (from 35,000 to 28,000), but is not statistically significant. Several processes which might be involved in the age-related changes observed are discussed, including the possibility of a shift from unmyelinated fibers to myelinated ones, withdrawal of corticobulbar fibers and ongoing outgrowth of myelinated corticofugal fibers after two months of age, and a summarizing scheme is presented. We conclude that the pyramidal tract of the rat changes in composition after the age of two months and that continuing outgrowth of myelinated corticospinal fibers is an important aspect of this continuing development. 相似文献
5.
The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice 总被引:1,自引:0,他引:1
Hans-Peter R. Bootsma †Albert P. Aldenkamp Leonie Diepman Jacques Hulsman Danielle Lambrechts Loes Leenen Marian Majoie Ad Schellekens †Marc de Krom 《Epilepsia》2006,47(S2):24-27
Summary: Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment.
Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant.
Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV. 相似文献
6.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
7.
Sex and age specific prediction formulas for estimating body composition from bioelectrical impedance: a cross-validation study 总被引:4,自引:0,他引:4
P Deurenberg K van der Kooy R Leenen J A Weststrate J C Seidell 《International journal of obesity (2005)》1991,15(1):17-25
In 827 male and female subjects, with a large variation in body composition and an age range of 7-83 years, body composition was measured by densitometry, anthropometry and bioelectrical impedance. The relationship between densitometrically determined fat free mass (FFM) with body impedance (R), body weight (W) and body height (H) was analysed, taking age and sex into account. The intercept of the regression equation FFM = a x H2/R + b was found to be age, and (at older ages) sex dependent, increasing from age 7 to age 15, and slowly decreasing after age 16. Therefore the population was subdivided into two age categories, the one 15 years and younger, and the other 16 years and older. Each age category was randomly divided into two groups, A and B. In each age category the developed prediction formula for group A was cross-validated in group B, and vice versa. No statistically and biologically meaningful differences between predicted and measured FFM were observed in either group. Therefore the data of group A and B in each age category were combined. The best fitted prediction formula at ages less than or equal to 15 was: FFM = 0.406 x 10(4) x H2/R + 0.360 W + 5.58 H + 0.56 Sex - 6.48: n = 166, R2 = 0.97, SEE = 1.68 kg (cv% = 4.9 percent); and at ages greater than or equal to 16: FFM = 0.340 x 10(4) x H2/R + 15.34 H + 0.273 W - 0.127 age + 4.56 sex - 12.44: n = 661, R2 = 0.93, SEE = 2.63 kg (cv% = 5.0 percent).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
9.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
10.
The purpose of the experiments described here was to test whether membrane-impermeant antibiotics present in the extracellular milieu could kill bacteria within macrophages. For this, mouse macrophage hybrids and elicited mouse peritoneal macrophages first were allowed to phagocytose the facultative intracellular bacterium Listeria monocytogenes. The cells were incubated with or without gentamicin, and their bactericidal activity was measured. The results show that gentamicin caused normally nonbactericidal macrophages to kill L. monocytogenes. In addition, gentamicin caused listericidal cells to kill significantly more bacteria. To determine whether gentamicin accumulated within macrophages during culture, we tested whether lysates of macrophage hybrids cultured for 72 h in gentamicin-containing medium and then washed could kill Listeria cells. When cultured with 50 to 100 micrograms of gentamicin per ml, but not when cultured with 0 to 5 micrograms of gentamicin per ml, cell lysates were extremely listericidal, demonstrating the presence of intracellular gentamicin. Because gentamicin does not penetrate cell membranes, we hypothesized that it can be internalized by the cell through pinocytosis and can enter the same intracellular compartment as does phagocytosed L. monocytogenes. To test this, macrophages which had phagocytosed L. monocytogenes were incubated with the fluorochrome lucifer yellow to trace pinocytosed medium. About half of the Listeria cells within the macrophages were surrounded by lucifer yellow, indicating delivery of pinocytosed fluid, which could contain antibiotics, to phagosomes containing bacteria. The experiments described here indicate that membrane-impermeant antibiotics can enter macrophages and kill intracellular bacteria. Thus, the use of gentamicin in macrophage bactericidal assays can interfere with the results and interpretation of experiments designed to study macrophage bactericidal activity. 相似文献