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131.
Iron deficiency (ID) is among the most common nutritional diseases, causing deleterious effects that include decreases in cognitive function and weight loss. The ID also induces a reduction in the number and affinity of dopaminergic D2 receptors. The new finding that ID induces an increase in the pancreas cells, leads to the hypothesis that cholecystokinin-8 (CCK-8) is involved in the ID effects. The level of CCK-8 was higher among ID rats, compared with normal rats. The ID rats in our study were anorectic and performed poorly in learning tests (Morris water maze and passive avoidance learning). Essential fatty acids (EFA) mediate dopamine activity and have been found to rehabilitate learning deficits. Treatment with a fatty acid compound blocked both the learning deficits and the anorexia, while a CCK-8 antagonist was successful only against the anorectic effects.  相似文献   
132.
Clozapine has been the gold standard for treatment of patients with refractory schizophrenia but is associated with serious safety liabilities. This has prompted the search for therapeutic alternatives for treatment-resistant schizophrenia. The objective of this study was to compare the efficacy and safety of olanzapine versus clozapine in schizophrenic patients who failed to respond adequately to antipsychotic medication or who experienced intolerable adverse effects associated with the medication. This 18-week, randomized, double-blind, parallel study compared treatment with either olanzapine (5-25 mg/day, n=75) or clozapine (100-500 mg/day, n=72) in patients with schizophrenia who were nonresponsive to, or intolerant of, standard acceptable antipsychotic therapy. At the 18-week endpoint, no statistically significant differences were found between olanzapine and clozapine in any efficacy measure used: Positive and Negative Syndrome Scale (PANSS) total, positive, negative, or general psychopathology or Clinical Global Impression severity (CGI-S). Response rates based on the criteria of Kane et al. [Arch. Gen. Psychiatry 45 (1988) 789] were also not significantly different between olanzapine-treated (57.9%) and clozapine-treated patients (60.8%). There were no significant differences in measurements of extrapyramidal symptoms or electrocardiography, and no clinically and statistically significant changes were seen in vital signs or laboratory measures in either group. Both treatments were well tolerated. Olanzapine demonstrated similar efficacy to clozapine in patients who had failed previous treatment because of lack of efficacy (treatment resistance) or intolerable side effects (treatment intolerance). Olanzapine therefore presents a safe alternative in the treatment of refractory schizophrenia.  相似文献   
133.
PURPOSE: A severity rating for each of the pediatric epilepsy syndromes can contribute to a more comprehensive understanding of seizure condition severity. We describe the development of the Epilepsy Syndrome Severity Scores-Child (ESSS-C). METHODS: The Delphi Technique was used to establish severity scores for pediatric epileptic syndromes as defined by the International League Against Epilepsy (ILAE). Pediatric neurologists with expertise in epilepsy were asked to rate the severity of each syndrome on a scale of 1 to 10, considering: (a) response to medical treatment, (b) seizure severity, and (c) long-term prognosis. Syndrome severity ratings took place in four different rounds. Experts provided initial scores in rounds 1 and 2. RESULTS: Of the 18 experts who agreed to participate in the development of the scale, 12 completed all four rounds. The median served as the syndrome severity score if the mean and median agreed within 0.5. Otherwise, whichever of these two numbers was closest to the mode was selected. Syndromes that were rated with high severity scores (9 or 10) or low severity scores (1 or 2) had unanimous or near unanimous ratings. The syndromes with scores in the middle range (4 to 8) had a wider range of ratings. CONCLUSIONS: If further studies provide empirical support for the validity of these epileptic syndrome severity scores, then the ESSS-C has potential for use both clinically and in future research in the prediction of outcomes of treatments.  相似文献   
134.
AIM: To rationalize decision making around the use of different non-steroidal anti-inflammatory drug (NSAID) treatment strategies in patients with varying degrees of gastrointestinal and cardiovascular risk. METHODS: The panel comprised nine physicians (three rheumatologists, two internists, two gastroenterologists and two cardiologists) from geographically diverse areas practising in community-based settings (n = 4) and academic institutions (n = 5). A literature review was performed by the authors on the risks, benefits and costs of NSAIDs, cyclo-oxygenase-2-specific inhibitors and proton pump inhibitor co-therapy. The RAND/UCLA Appropriateness Method was used to rate 304 clinical scenarios as 'appropriate', 'uncertain' or 'inappropriate'. RESULTS: In patients with no previous gastrointestinal event and not concurrently on aspirin (low risk), the panel rated the use of an NSAID alone as 'appropriate' for those aged < 65 years, and the use of an NSAID +proton pump inhibitor or cyclo-oxygenase-2-specific inhibitor + proton pump inhibitor as 'inappropriate'. For patients aged > 65 years and at low risk, an NSAID or cyclo-oxygenase-2-specific inhibitor alone was rated as 'uncertain'. For patients with a previous gastrointestinal event or who concurrently received aspirin, an NSAID alone was rated as 'inappropriate', and either a cyclo-oxygenase-2-specific inhibitor or an NSAID +proton pump inhibitor was rated as 'appropriate'. Finally, for patients with a previous gastrointestinal event and on aspirin, an NSAID or cyclo-oxygenase-2-specific inhibitor in conjunction with a proton pump inhibitor was rated as 'appropriate'. CONCLUSIONS: Clinicians and managed care entities need to balance the risks, benefits and costs of NSAIDs, cyclo-oxygenase-2-specific inhibitors and the prophylactic use of proton pump inhibitors. The guidelines given here can assist this process.  相似文献   
135.
OBJECTIVE: The purpose of this study was to evaluate the effect of N-acetylcysteine on the activity and secretion of the matrix metalloproteinases in the decidua, amnion, and chorion and the secretion of the tissue inhibitor of matrix metalloproteinase-1. STUDY DESIGN: Samples from eight nonlaboring women were taken at elective cesarean section and incubated in an in vitro organ culture in the absence or presence of N-acetylcysteine. Matrix metalloproteinase-2 and matrix metalloproteinase-9 activity was measured with the use of gel zymography. Western blot analysis was used to measure matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase-1 secretion. Data were analyzed with the paired Student t test. RESULTS: N-acetylcysteine had a direct inhibitory effect on matrix metalloproteinase-2 and matrix metalloproteinase-9 activity, regardless of tissue origin, starting at 1.0 mmol/L. In cultured media, 20 mmol/L N-acetylcysteine inhibited matrix metalloproteinase-2 and matrix metalloproteinase-9 activity in all three tissues. A differential response was demonstrated for matrix metalloproteinase-2 secretion, depending on the tissue that was studied. Its secretion was decreased in decidua at 10 mmol/L and 20 mmol/L; in amnion, the secretion was inhibited at 0.1 mmol/L and not affected at all in chorion. Matrix metalloproteinase-9 secretion was not affected in a statistically significant manner in any tissue. In the chorion, matrix metalloproteinase-9 showed a trend toward increased secretion. Tissue inhibitor of matrix metalloproteinase-1 secretion significantly decreased in the decidua at 20 mmol/L. CONCLUSION: N-acetylcysteine, at higher concentrations, has an inhibitory effect on matrix metalloproteinase-2 and matrix metalloproteinase-9 activity, regardless of the tissue origin and the differential effect on secretion depending on the tissue and N-acetylcysteine concentration.  相似文献   
136.
OBJECTIVES: To establish a nomogram for early fetal kidney development during early gestation. METHODS: The study is a prospective, cross-sectional evaluation of 275 male and female fetuses between 13 and 22 weeks in normal singleton pregnancies. Measurements of fetal kidney length were performed by high resolution transvaginal ultrasonography between 14 and 17 weeks' gestation, and by transabdominal ultrasonography beyond 18 weeks' gestation. RESULTS: Adequate kidney length measurements were obtained in all 275 normal fetuses as well as in six fetuses with urinary tract anomalies. Kidney length as a function of gestational age was expressed by the regression equation: (square root) kidney length (mm) = -11.66 + 1.52 x gestational age (weeks). The correlation coefficient, r = 0.983 was found to be highly statistically significant (p < 0.0001). The normal mean and the 90% prediction limits were defined. Four cases with single kidney and two cases with posterior urethral valve had kidney length above the 95% upper limit. CONCLUSION: The present data offer a normal range of fetal kidney length from early stages of gestation that may allow intrauterine assessment of its development. It may also be helpful in the early prenatal diagnosis of renal abnormalities.  相似文献   
137.
The aim of this study was to examine whether maternal serum uric acid (UA) concentrations are influenced by the number of fetuses and whether this effect is confounded by maternal body mass index (BMI). Medical records of 207 consecutive twin and 69 triplet pregnancies admitted to our high-risk pregnancy unit between 1994 and 1998 were reviewed. Pregnancies complicated by acute or chronic renal diseases, vascular diseases, hypertension, hemolysis, diabetes mellitus, or proteinuria were excluded. The remaining 137 twin and 42 triplet pregnancies were matched with 118 consecutive singleton pregnancies who met the same exclusion criteria and were admitted in the first half of 1998. Each birth order study group was further stratified and compared within three maternal BMI subgroups. Serum UA concentrations were higher in twin and triplet pregnancies compared to singletons (4.6 +/- 1.3, 5.2 +/- 1.2, and 3.8 +/- 0.7 mg%, respectively; p <0.01). These differences in UA concentration persisted after grouping by BMI classes. Serum UA concentration in pregnancy are positively correlated with the number of fetuses. For clinical purpose, the UA cutoff concentration should be adjusted using mean + 2 SD as follows: 5.2, 7.2, and 7.6 for singleton, twin, and triplets, respectively.  相似文献   
138.
OBJECTIVE: To identify the risk factors for preterm birth in primigravidae with twin gestation and the role of transvaginal ultrasonographic assessment of the cervix. METHODS: Between January 1996 and December 1996, 54 twin pregnancies were prospectively enrolled. All women were at their first pregnancy. All women conceived following infertility treatments and all had a normal uterine cavity proven by hysterosalpingography (HSG) or hysteroscopy. Multiple logistic regression analysis was used to evaluate the association between the length of the cervix at 18-24 weeks of gestation and outcome variables, controlling for possible confounding factors. RESULTS: The mean +/- SD maternal age was 30.9 +/- 5.3 years (range 22-46), and five of them were aged 40 or more. Nine patients (20.5%) delivered prematurely, defined as spontaneous delivery at or before 34 weeks of gestation. There was no statistically significant difference between women who delivered before or after 34 weeks of gestation in regard to maternal age, body mass index (BMI), weight gain in pregnancy, smoking and work during pregnancy. The mean cervical length of patients who delivered before 34 weeks of gestation (30.1 +/- 6.1 mm) was significantly shorter than that of women who delivered after 34 weeks of gestation (42.2 +/- 6.2 mm; P < 0.001). Cervical length longer than 35 mm predicted delivery after 34 weeks of gestation with sensitivity and specificity of 88.5% and 88.9%, respectively. The positive and negative predictive values were 96.9% and 66.7%. CONCLUSION: A transvaginal ultrasonographic measurement of the cervix > 35 mm at 18-24 weeks in twin gestation can identify patients at low risk for delivery before 34 weeks. Maternal age, BMI, weights gain, smoking and work during the pregnancy did not influence the duration of the pregnancy.  相似文献   
139.
In vitro fertilization is a risk factor for vasa previa   总被引:2,自引:0,他引:2  
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140.
BACKGROUND: We have previously suggested that helminthic infections make the host more susceptible to HIV infection and enhance its progression due to the chronic immune activation they cause. OBJECTIVE: To study the effect of antihelminthic treatment on HIV plasma viral load (VL) in HIV- and helminth-infected individuals living in Ethiopia. METHODS: Fifty-six clinically asymptomatic HIV-1-infected individuals, 31 (55%) of whom were also infected with helminths, were studied. All participants received antihelminthic treatment at baseline and at 3 and 6 months. Worm egg excretion, HIV plasma VL, and T-cell subsets were determined at baseline and 6 months after treatment. RESULTS: The mean age, number of CD4 T cells, and gender distribution were similar in the helminth-infected and -noninfected groups. At baseline, HIV plasma VL was strongly correlated to the number of eggs excreted (p <.001) and was higher in individuals infected with more than one helminth (5.28 +/- 0.35 versus 4.30 +/- 1.13 log RNA copies/mL, respectively; p =.16). After treatment of helminths, the 6-month change in HIV plasma VL was significantly different between the successfully treated group and the persistently helminth-positive group (p =.04) CONCLUSIONS: Helminth "load" is correlated to HIV plasma VL, and successful deworming is associated with a significant decrease in HIV plasma VL. The results of the current study, if confirmed in a larger study, may have important implications for slowing disease progression and reducing risks of transmission.  相似文献   
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