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81.
BACKGROUND: Since treatment approaches thought to be useful for mania are presumably suitable for hypomania as well, little systematic research has been done on the treatment of hypomanic episodes and their long-term outcome. As systematic trials have shown that the atypical antipsychotic risperidone may be effective and safe in the treatment of acute mania, we decided to conduct an open-label study of its effectiveness and tolerability in hypomania associated with bipolar II. METHODS: Forty-four DSM-IV bipolar II patients with Young Mania Rating Scale (YMRS) scores above 7 were included and followed-up for 6 months. Efficacy was measured by means of the YMRS and the Clinical Global Impression for Bipolar Disorder (CGI-BD). Treatment-emergent depression was measured by the Hamilton Depression Rating Scale (HDRS-17), and the Udvalg for Kliniske Unders?gelser (UKU) subscale was used for neurological/extrapyramidal side-effects. RESULTS: Thirty-four patients completed the trial. The mean dose of risperidone at endpoint was 2.8 mg/day. Last observation-carried-forward analysis showed significant reduction of YMRS scores from the first week of treatment, which continued until the endpoint (P<0.0001). At 6-month follow-up, 60% of patients were assymptomatic according to the CGI. The 32% who received risperidone in monotherapy seemed to respond equally well. Risperidone, as used in this study, appeared to be most protective against hypomanic than depressive recurrences. Nine patients (12%) had a depressive relapse during 6-month follow-up, one patient (2%) had an hypomanic relapse and another (2%) had both. No patients developed tardive dyskinesia during the duration of the study. Although most patients received risperidone in combination with standard mood-stabilizers, only three patients discontinued risperidone because of other side-effects. LIMITATIONS: In the absence of a placebo arm, it is uncertain to what extent the foregoing results could be ascribed to spontaneous remission of bipolar II disorder. CONCLUSIONS: Risperidone, either in combination with mood-stabilizers or alone was well-tolerated in bipolar II patients, who presented in a hypomanic state, and appeared efficacious. Further controlled research on the role of atypical antipsychotics in the treatment of less-than-manic forms of bipolar illness is warranted.  相似文献   
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The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
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Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed.  相似文献   
86.
Low serum vitamin B(12) concentrations in pregnancy may not indicate true megaloblastic anaemia. In the present study we compared biochemical indices of vitamin B(12) deficiency (serum homocysteine and urine methylmalonic acid) in non-anaemic pregnant women with and without low serum vitamin B(12) concentrations. The groups were matched for age, parity and gestational age. No differences were found, and all values were within normal range. These results suggest that the measurement of low serum B(12) concentrations in pregnant women should be followed by analysis at the biochemical level before vitamin B(12) injections are started.  相似文献   
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An assessment of gene prediction accuracy in large DNA sequences   总被引:11,自引:2,他引:11       下载免费PDF全文
One of the first useful products from the human genome will be a set of predicted genes. Besides its intrinsic scientific interest, the accuracy and completeness of this data set is of considerable importance for human health and medicine. Though progress has been made on computational gene identification in terms of both methods and accuracy evaluation measures, most of the sequence sets in which the programs are tested are short genomic sequences, and there is concern that these accuracy measures may not extrapolate well to larger, more challenging data sets. Given the absence of experimentally verified large genomic data sets, we constructed a semiartificial test set comprising a number of short single-gene genomic sequences with randomly generated intergenic regions. This test set, which should still present an easier problem than real human genomic sequence, mimics the approximately 200kb long BACs being sequenced. In our experiments with these longer genomic sequences, the accuracy of GENSCAN, one of the most accurate ab initio gene prediction programs, dropped significantly, although its sensitivity remained high. Conversely, the accuracy of similarity-based programs, such as GENEWISE, PROCRUSTES, and BLASTX was not affected significantly by the presence of random intergenic sequence, but depended on the strength of the similarity to the protein homolog. As expected, the accuracy dropped if the models were built using more distant homologs, and we were able to quantitatively estimate this decline. However, the specificities of these techniques are still rather good even when the similarity is weak, which is a desirable characteristic for driving expensive follow-up experiments. Our experiments suggest that though gene prediction will improve with every new protein that is discovered and through improvements in the current set of tools, we still have a long way to go before we can decipher the precise exonic structure of every gene in the human genome using purely computational methodology.  相似文献   
89.
Using a method that detects variations in light intensity we have studied the effect of ovarian steroids on human Fallopian tube epithelial ciliary beat frequency in vitro. We have found that baseline ciliary beat frequency averages between 5-6 Hz. Cilia from ampullary segments of the Fallopian tube beat significantly faster (5.4 Hz+/-0.2) than those from fimbrial segments (4.8 Hz+/-0.2). There was no significant difference in baseline ciliary beat frequency at any other anatomical site in the Fallopian tube. Incubation with progesterone (10 micromol/l) suppresses human Fallopian tube epithelial ciliary beat frequency by 40-50%. This inhibition was observed at similar magnitudes in all Fallopian tubes studied irrespective of anatomical site. Progesterone-induced reductions in ciliary beat frequency were concentration dependent and prevented by the progesterone receptor antagonist mifepristone (RU486). Oestradiol alone (10 micromol/l) had no effect on ciliary beat frequency at any anatomical site in the Fallopian tube but did prevent the reduction in ciliary beat frequency seen with progesterone when tissues were incubated with these two steroids together.   相似文献   
90.
Dorsal commissural axons in the developing spinal cord cross the floor plate, then turn rostrally and grow along the longitudinal axis, close to the floor plate. We used a subtractive hybridization approach to identify guidance cues responsible for the rostral turn in chicken embryos. One of the candidates was the morphogen Sonic hedgehog (Shh). Silencing of the gene SHH (which encodes Shh) by in ovo RNAi during commissural axon navigation demonstrated a repulsive role in post-commissural axon guidance. This effect of Shh was not mediated by Patched (Ptc) and Smoothened (Smo), the receptors that mediate effects of Shh in morphogenesis and commissural axon growth toward the floor plate. Rather, functional in vivo studies showed that the repulsive effect of Shh on postcommissural axons was mediated by Hedgehog interacting protein (Hip).  相似文献   
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