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排序方式: 共有1163条查询结果,搜索用时 15 毫秒
91.
Burglen F Marczewski P Mitchell KJ van der Linden M Johnson MK Danion JM Salamé P 《Psychiatry research》2004,125(3):247-255
This study investigated feature binding in a working memory task in patients with schizophrenia and in normal controls. Twenty-five patients and 25 controls participated. On each trial, three drawings of familiar objects were presented sequentially, each in a different cell of a 3 x 3 grid. In different blocks of trials, participants remembered either individual features (object and location conditions) or an object and its location (combination condition). The results showed that patients were slower and less accurate than controls under all conditions. Accuracy of both groups was reduced in the combination condition relative to the single-feature conditions, but patients showed disproportionately poorer performance in the combination condition than in the object and location conditions. Thus, patients with schizophrenia exhibit deficits in working memory, particularly when the task requires binding objects to their locations. This finding demonstrates that processes that establish coherent and temporary episodic representations in working memory are impaired in schizophrenia. 相似文献
92.
Guy Huel Chadi Yazbeck Daniel Burnel Pascale Missy Wolfram Kloppmann 《Toxicological sciences》2004,80(2):304-309
Following boron intake, multiple effects have been observed in animal experiments. However, human data is lacking, and no data is available on the ability of boron to accumulate in fetal tissues. Positive responses in animal species suggest that developmental toxicity may be an area of concern in humans, following exposure to boron. Two hypotheses have seemed to account for the multiple effects described in scientific findings. One hypothesis is that boron is a negative regulator that influences a number of metabolic pathways by competitively inhibiting some key enzyme reactions. The other hypothesis is that boron has a role in ionic membrane transport regulations. To better understand boron potential toxicity, the present study examined the relationship between boron exposure and some key enzymes, well-known for their affinity for mineral elements, such as delta-aminolevulinic acid dehydratase (ALA-D), and two fundamental enzymes having a role in ionic membrane transport regulations (Ca-pump and Na(+)K(+)-ATPase). We investigated the potential effects of an environmental boron exposure on the activity of these enzymes in an urban population of 197 "normal" newborns. Environmental boron exposure was assessed in placental tissue. Because of the well-known inhibiting effect of lead on these enzymes, cord blood and placental lead were also analyzed. After adjustment for potential confounders, including lead, placental boron levels were negatively significantly correlated to ALA-D activity while Ca-pump and Na(+)K(+)-ATPase activities did not seem to be affected by the level of boron exposure. Given boron's ability, as a Lewis acid, to complex with hydroxyl groups, we suggest that such a mechanism would explain the inhibiting effect of boron on ALA-D. 相似文献
93.
94.
Salam AM 《Expert opinion on investigational drugs》2003,12(3):501-507
There is strong evidence from controlled clinical trials that in the setting of acute myocardial infarction complicated by heart failure or isolated left ventricular dysfunction, angiotensin-converting enzyme inhibitors started late during hospitalisation and continued in the long term, significantly reduced mortality and improved the prognosis. On the other hand, administration of angiotensin-converting enzyme inhibitors during the first 24 h in unselected patients with acute myocardial infarction provided only a slight benefit in terms of mortality. Angiotensin-II receptor blockers have and are being examined in the setting of acute myocardial infarction with left ventricular dysfunction and can provide an alternative for patients who cannot tolerate angiotensin-converting enzyme inhibitors. In this article, an evidence-based review of these major trials and suggestions for clinical application are presented. 相似文献
95.
Prostate cancer is a common malignancy affecting men, which is often associated with skeletal metastases resulting in significant morbidity and mortality. In this hormone-dependent cancer, low levels of a prostate secretory protein of 94 amino acids (PSP-94) are associated with advanced disease stage. In the current study, we have examined the effect of PSP-94 on prostate cancer growth and experimental metastases to the skeleton. For these studies, MatLyLu rat prostate cancer cells were transfected with full-length cDNA encoding parathyroid hormone-related protein [PTHrP (MatLyLu-PTHrP cells)], which is known to be the major pathogenetic factor for malignancy-associated hypercalcemia. MatLyLu-PTHrP cells were inoculated s.c. into the right flank or via intracardiac route into the left ventricle of syngeneic male Copenhagen rats. Intracardiac inoculation of MatLyLu cells routinely results in the development of tumors in the lumbar vertebrae, resulting in hind-limb paralysis. Animals were infused with different doses of PSP-94 (0.1, 1.0, and 10.0 micro g/kg/day) starting on the day of tumor cell inoculation. Time of hind-limb paralysis and tumor volume were determined, and comparison was made between PSP-94-treated animals and control animals receiving vehicle alone. At the end of the study, animals were sacrificed, and plasma calcium, plasma PTHrP, and tumor PTHrP levels were determined. Whereas the highest dose of PSP-94 caused a modest but statistically significant delay in the development of hind-limb paralysis, a marked dose-dependent decrease in primary tumor volume was seen in experimental animals receiving PSP-94 due to its ability to promote tumor cell apoptosis. Furthermore, whereas control animals routinely developed hypercalcemia due to PTHrP production, treatment with PSP-94 led to a near normalization of plasma calcium and a marked reduction in PTHrP production as determined by radioimmunoassay and immunohistochemistry. Collectively, these results demonstrate the ability of PSP-94 to be an effective treatment modality for prostate cancer, where decrease in plasma PTHrP and calcium levels can serve as useful biochemical markers for monitoring the efficacy of this novel antitumor agent. 相似文献
96.
Perarnau JM Daradkeh S Johann M Deneuville M Weinling P Coniel C 《Hepato-gastroenterology》2003,50(51):610-613
BACKGROUND/AIMS: Because of our previous experience with transjugular intrahepatic portosystemic shunt, we decided to apply the transjugular approach to preoperative portal embolization. The aim of this pilot study was to determine the feasibility and the potential advantages and disadvantages of this new method. METHODOLOGY: Under ultrasound guidance the right or left portal branch was punctured from the right, median or left hepatic vein. Then, a catheter was placed near the portal bifurcation and used to perform right portal branch embolization with a mixture of Histoacryl and Lipiodol. Pre- and post-transjugular preoperative portal embolization duplex ultrasound and CT scan were performed to assess portal flow and liver tissue growth. Hospital stay, pain and hepatic enzymes were monitored. RESULTS: Fifteen patients underwent a transjugular preoperative portal embolization without any serious complication. Mean of hospital stay was 3.3 +/- 0.6 days. (2-5 days). Portal embolization was successful in all cases; left portal branch velocity increased from 11.8 +/- 7.5 cm/s before, to 16.5 +/- 3.5 cm/s on day one, and 14.8 +/- 3.3 cm/s on day 28 after transjugular preoperative portal embolization; volume of non-embolized segments increased by 10% within the 4 weeks after transjugular preoperative portal embolization. Right hepatectomy was possible in 12 patients CONCLUSIONS: This method is safe, painless, and can be proposed in cases of impossibility to perform the standard percutaneous transhepatic portal embolization (tumor interposition, impaired hemostasis). 相似文献
97.
Bénateau H Labbé D Elissalde JM Salamé E 《Annales de chirurgie plastique et esthétique》2001,46(6):611-616
The lengthening temporalis myoplasty is indicated in long standing and congenital facial paralysis. Its principle is the transfer of the coronoid tendinous insertions onto the lip and the nasolabial fold. The knowledge of the anatomy of this strong and wide tendon is necessary to use successfully their anatomical advantages. A study of ten cadavers (20 temporalis muscles) confirmed the surgical anatomy found during lengthening temporalis myoplasty procedure: the strong tendon, when liberated from the coronoid process, is from 4 to 6 cm long. 相似文献
98.
Guemei AA Cottrell J Band R Hehman H Prudhomme M Pavlov MV Grem JL Ismail AS Bowen D Taylor RE Takimoto CH 《Cancer chemotherapy and pharmacology》2001,47(4):283-290
PURPOSE: To characterize the relationships between human plasma irinotecan carboxylesterase-converting enzyme activity, caboxylesterase-mediated hydrolysis of p-nitrophenyl acetate (pNPA), and the butyrylcholinesterase-mediated hydrolysis of butyrylthiocholine in human plasma and to test the ability of these in vitro tests to predict the variability in SN-38 pharmacokinetics in adult patients during a prolonged infusion of irinotecan. METHODS: Individual plasma-converting enzyme activity was measured in 20 adult cancer patients participating in a pharmacokinetic and phase I clinical trial of a prolonged 96-h intravenous infusion of irinotecan. The pNPA and butyrylthiocholine hydrolysis in patient plasma was also assayed. RESULTS: The irinotecan carboxylesterase-converting enzyme in human plasma had a Vmax of 89.9 +/- 22.7 pmol/h per ml plasma and a Km of 207 +/- 56 microM (mean +/- SD, n = 3). The mean value of the specific activity of this enzyme in 20 adult cancer patients was 10.08 +/- 2.96 pmol/h per ml plasma ranging from 5.43 to 15.39 pmol/h per ml. The area-under-the-concentration-versus time curve (AUC) ratio of SN-38 to irinotecan (AUCSN-38/AUCCPT-11) was used to assess the relative SN-38 exposure to the active metabolite in individual patients. Pharmacokinetic variations in the relative exposure to SN-38 did not correlate with the measured carboxylesterase-converting enzyme activity nor with plasma butyrylcholinesterase activity in our patient population. However, it did correlate with the measured pNPA hydrolysis activity in patient plasma (r2 = 0.350, P = 0.0124, n = 18). CONCLUSIONS: Determination of patient plasma pNPA hydrolysis activity may have utility in predicting SN-38 pharmacokinetics during prolonged infusions of irinotecan. 相似文献
99.
Orit Taubman – Ben-Ari Miriam Chasson Salam Abu Sharkia Efrat Weiss 《Journal of reproductive and infant psychology》2020,38(3):340-348
ABSTRACT
Introduction
The fact that little is yet known about the possible implications of COVID-19 for pregnancy, puts pregnant women at greater risk of heightened anxiety and psychological distress. In this study, we sought to explore the psychological distress and COVID-19-related anxiety of pregnant women during the crisis. 相似文献100.