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21.
Cognitive function after on or off pump coronary artery bypass grafting.   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate cognitive outcome after on and off pump coronary artery bypass grafting. METHODS: Seventy patients between 50 and 80 years with stable angina pectoris, ejection fraction >30%, serum creatinine <150 micromol/l, and lack of tight main stem stenosis were randomized to on or off pump coronary artery bypass grafting. Standardized neuropsychological tests evaluated attention, verbal and visuo-spatial short-term and working memory, verbal learning, delayed recall, visuo-motor speed, and aspects of executive functions. Levels of anxiety and depression were also investigated. Testing was performed before and at 1 week, 1 and 6 months after surgery. RESULTS: There was no difference in cognitive impairment (defined as a 20% reduction in at least 20% of the tests) between groups. The incidence at 1 week post-operatively was 57% in the on pump group and 58% in the off pump group, after 1 month 30% and 12% and after 6 months 19% and 15%, respectively (p for interaction=0.19). There was no difference between groups in anxiety (p=0.18) or depression (p=0.48). CONCLUSIONS: This prospective, randomized study showed no differences in post-operative cognitive function after on pump compared to off pump coronary artery bypass grafting in low risk patients.  相似文献   
22.
Spray coated pellets as carrier system for mucoadhesive drug nanocrystals.   总被引:1,自引:0,他引:1  
High pressure homogenization can be employed to produce drug nanocrystals with a number of advantages, like improved solubility behaviors, better drug targeting or even increased mucoadhesiveness. To obtain a controlled drug delivery system it is necessary to transform the resulting nanosuspension into a solid dosage form. The present study shows the feasibility to use a mucoadhesive nanosuspension of poorly soluble hydrocortisone acetate produced by high pressure homogenization as layering dispersion in a fluidized bed process, followed by the application of an enteric coating to achieve a controlled drug release. To point out the advantages of drug nanocrystals the new fomulation was compared with a formulation containing micronized drug. Both formulations were characterized with regard to their particle size and crystallinity by using laser diffractometry, photon correlation spectroscopy and X-ray diffraction. The pellet morphology was characterized by using the environmental scanning electron microscopy (ESEM). In the in vitro dissolution tests an accelerated dissolution velocity and an increased drug release could be shown for the pellets containing drug nanocrystals.  相似文献   
23.
The lack of estrogen during menopause is associated with various symptoms including osteoporosis, cardiovascular diseases, and menopausal symptoms. For many years, conventional hormone replacement therapy has been successfully used to treat these conditions. However, in light of recent studies that draw attention to potential hazards of conventional HRT, various attempts were undertaken to search for alternatives of classical HRT. Phytoestrogens are supposed to ameliorate various discomforts associated with menopause. Resveratrol (RES) is present in red wine, grapes and peanuts and has been implicated in cardioprotection and prevention of adverse side effects observed after regular HRT. As the pituitary-thyroid axis is a target of estrogen action, we first assessed the effects of E2 administration on thyroid hormone stimulating hormone releasing hormone (TRH)-induced thyroid stimulating hormone (TSH) secretion from pituitary cell cultures in vitro. Our data reveal that E2 treatment augments the TRH-induced TSH secretion. We furthermore designed a long-term study of three months to assess the effects of subcutaneous and oral administration of 17beta-estradiol (E2), as well as the actions of RES on the pituitary-thyroid axis in ovariectomized (OVX) female rats. Our results demonstrate that serum levels of 1.0 and 8.1 microM RES lead to a significant increase in total serum triiodthyronine (T3) levels. OVX induces TSHbeta mRNA in the adenohypohysis and E2 treatment attenuates this effect. Treatment of rats with subcutaneous implants of E2 does not affect the pituitary-thyroid axis, whereas orally applied E2 benzoate (E2B) increases plasma TSH and total thyroxine (T4) in OVX rats. In all animals, we could not detect changes in thyroid morphology as assessed by hematoxylin-eosin (HE) and Perjod-Acid Schiff's (PAS) staining.  相似文献   
24.
AIM: To compare the effects of 17beta-estradiol given intranasally (intranasal E2) and raloxifene on serum lipid profile and fibrinogen in hypercholesterolemic postmenopausal women. METHODS: The study population consisted of 46 women after menopause. The placebo group (n = 11) was given calcium, while the intervention groups were given intranasal E2 (Aerodiol; Servier, Chambray-les-Tours, France) (n = 16) or raloxifene (Evista; Lilly SA, Madrid, Spain) (n = 19). Blood lipids and fibrinogen were compared between groups at baseline and after 3 months of treatment. RESULTS: The group receiving intranasal E2 showed a significant decrease in triglyceride levels (p<0.05) and a marked increase in high-density lipoprotein cholesterol levels (p<0.05). No changes in lipid profile were observed in the raloxifene and placebo groups. Raloxifene caused a significant decrease in fibrinogen levels (p<0.05). CONCLUSION: Intranasal E2 exerts significant effects on lipid profile in hypercholesterolemic postmenopausal women. Raloxifene has a greater impact on fibrinogen than intranasal E2 application.  相似文献   
25.
Placenta is an important source of leptin during pregnancy that contributes to the high plasma leptin levels in pregnant women. Leptin and its functional receptors are synthesized in trophoblast cells that, in turn, secrete gestational hormones supporting a paracrine or autocrine role for leptin in the endocrine activity of the placenta. In the present study we examined the effect of leptin on in vitro release of gestational hormones (human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone, estrogens and testosterone) by human term placental cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Progesterone, hCG, hPL, estradiol, estrone, estriol and testosterone levels were measured by different assays in culture media of cells maintained in monolayer culture after incubation for 12, 24, 48 or 72 h with leptin or placebo. Incubation with leptin did not modify hCG, hPL, progesterone, estriol and estrone secretion for any of the doses and times assayed. However, leptin led to a dose-dependent decrease in estradiol release. This effect was observed when treatment with recombinant human leptin spanned from 12 to 72 h. At this time an increase in testosterone levels was observed in leptin-treated cells versus placebo. These results indicate that leptin can be considered a gestational hormone implied in the endocrine function of the placenta, with an important role in control of the production of steroid reproductive hormones in placental cells in vitro.  相似文献   
26.
Bleeding disorders encountered during administration of hormone replacement therapy (HRT) are reviewed. The incidence of bleeding disorders is dependent on the phase of HRT and the age of the patient. In the diagnosis of these bleedings transvaginal sonography and minihysteroscopy are very important methods. Endometrial thickness can be monitored exactly by transvaginal sonography. Outpatient minihysteroscopy without anesthesia results in higher compliance to HRT after the procedure. In hormonal treatment of bleeding disorders during HRT, the sonographically supported progestogen test is very useful and can reduce endometrium thickness. Operative treatments include myoma and polyp resection as well as endometrial ablation. By these methods a high rate of bleeding-free HRT can be reached. The problem of endometrial cancer during HRT is discussed on the basis of new literature and critical statements. The review shows the importance of individual diagnostic and treatment schedules for bleeding disorders during HRT.  相似文献   
27.
AIM: The aim of the present study was to investigate the influence of endogenous estradiol and estrogen and estrogen-progestin therapies on concentration in pre- and postmenopausal women. MATERIALS AND METHODS: The study groups consisted of 26 women with surgical menopause (mean+/-standard deviation (SD): age 51.8+/-2.6 years, body mass index (BMI) 26.45+/-4.56 kg/m(2)), 54 with natural menopause (mean+/-SD: age 50.5+/-3.0 years, BMI 25.75+/-4.09 kg/m(2)) and 40 premenopausal controls (mean+/-SD: age 48.3+/-2.3 years, BMI 26.23+/-4.12 kg/m(2)). The group with surgical menopause received estradiol transdermally (50 microg/day) and those with natural menopause received additionally medroxyprogesterone acetate (5 mg/day) for the last 12 days of the cycle. Before and after 4 months of therapy, body weight, waist and hip circumferences and blood pressure were measured, and BMI and waist-to-hip ratio (WHR) were calculated. Serum leptin, follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, prolactin and dehydroepiandrosterone sulfate (DHEAS) were measured prior to and after treatment. RESULTS: Leptin concentrations did not differ statistically among the groups. No correlations between leptin and E(2), FSH, prolactin, testosterone and DHEAS concentrations were found in any of the groups before and after treatment. Leptin level correlated positively with body mass, BMI and hip and waist circumferences in all groups. There were no correlations between leptin and WHR in the pre- and postmenopausal groups. In the premenopausal group and in some postmenopausal groups, serum leptin level correlated with blood pressure. CONCLUSIONS: Endogenous E(2) and androgens in premenopausal women and estrogen and estrogen-progestin therapies in postmenopausal subjects do not influence serum leptin concentrations. Leptin level is related to body mass and BMI, but not to sex hormone status. The distribution of adipose tissue and the type of obesity (android or gynoid) have no influence on serum leptin concentration. The correlation between serum leptin level and blood pressure requires further investigation.  相似文献   
28.
Serum levels of bone markers N-mid osteocalcin (OCN-Mid) and Cross-Laps in 20 patients (8 men and 12 women) with loosening of at least one element of total hip endoprosthesis confirmed during operation were compared with age and sex matched group with OA. Marker levels were measured by direct chemoluminescency using Modular E-170. Statistical analysis were done with t-Student test (alpha = 0.05). There were no significant differences in OCN-Mid, Cross-Laps levels and OCN-Mid/Cross-Laps ratio between both groups. Implant loosening is a slow process taking place on a relatively small surface in comparison to whole skeleton, so bone markers have no clinical value in diagnostics of total hip loosening.  相似文献   
29.
INTRODUCTION: Transesophageal echocardiography (TEE) has become increasingly useful in the study of patients with suspected pulmonary thromboembolism. OBJECTIVE: The aim of this study was to prospectively evaluate the usefulness of TEE in the study of the distal part of the left pulmonary artery (LPA) as well as the influence of this procedure on total echocardiographic exam duration. METHODOLOGY: A prospective study in two groups of consecutive patients referred for TEE with a one- year interval between evaluation of Group A: 33 patients, 17 male, mean age 54 +/- 24 years, and Group B: 42 patients, 20 male, mean age 48 +/- 27 years (p = NS). The procedure was considered long when it took more than 3 min to evaluate the distal part of the LPA. RESULTS: In group A we were able to visualize the distal part of the LPA in 24 patients (73%) without significant prolongation of total exam duration in 16 patients (48% of group A). In one of the patients with suspected pulmonary thromboembolism thrombi were only observed in the distal part of the LPA. In group B we were able to visualize the distal part of the LPA in 36 patients (86%) without significant prolongation of total exam duration in 26 patients (61% of group B). CONCLUSIONS: 1. Visualization of the distal part of the LPA was possible in more patients, and with TEE time prolongation in less patients, in group B. These differences can be accounted for by the training of the operator in this technique. 2. The importance of visualization of this part of the LPA in guiding treatment in the subset of patients with pulmonary thromboembolism confirms the usefulness of this specific procedure.  相似文献   
30.
The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies.  相似文献   
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