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In the human hypothalamus, arginine-vasopressin (AVP) is produced for a major part by the neurones of the supraoptic nucleus (SON). Since plasma AVP levels in men were reported to be higher than those of women and we did not find a sex difference in the neurone number, a higher vasopressinergic neurone activity was supposed to be present in the SON of men. Therefore we studied the size of the Golgi-apparatus (GA), which has been demonstrated previously to be a sensitive parameter for protein synthetic ability of neurones, in 15 men and 17 women ranging in age from 29 to 94 years. A polyclonal antibody against immunoaffinity purified MG-160, a sialoglycoprotein of the medial cisternae of the GA was applied on paraffin-embedded sections containing the dorsolateral SON (dl-SON) from which 90-95% of neurones are vasopressinergic. SON areas that contain oxytocin (OT) cells were excluded on the basis of adjacent sections stained with a monoclonal antibody against OT. By means of an image analysis system the size of the GA and the cellular profile area were determined in dl-SON neurones with a nucleolus. Our results showed indeed an age-dependent sex difference in the size of the GA that appeared to be twice as large in young men (< or = 50 years old) than in young women of the same age. The size of the GA increased with age in women but not in men. In addition, the mean cell profile area, another measure for neuronal activity, was significantly larger in young men than in young women and was in old women larger than in young women. In conclusion, these data show the presence of a sex-dependent age-difference in the activity of vasopressinergic neurones in dl-SON which may relate to differences in AVP and sex hormone levels and kidney AVP receptors.  相似文献   
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Rational

A growing body of evidence illustrates that 5-HT3 receptor antagonist drugs may be of benefit in the treatment of negative symptoms in schizophrenia.

Objective

The objective of this study was to assess the efficacy and tolerability of tropisetron add-on to risperidone on negative symptoms in patients with chronic stable schizophrenia.

Methods

In a double-blind, placebo-controlled 8-week trial, 40 patients with chronic schizophrenia who were stabilized on risperidone were randomized into tropisetron or placebo add-on groups. Psychotic symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) every 2 weeks. Furthermore, extrapyramidal and depressive symptoms as well as side effects were assessed. The primary outcome measure was the difference in change from baseline of negative subscale scores between the two groups at week 8.

Results

Tropisetron resulted in greater improvement of the total PANSS scores [F(1.860,70.699)?=?37.366, p?<?0.001] as well as negative scores [F(2.439,92.675)?=?16.623, p?<?0.001] and general psychopathology [F(1.767,67.158)?=?4.602, p?=?0.017], but not positive subscale scores [F(1.348, 51.218)?=?0.048, p?=?0.893] compared to placebo. In a multiple regression analysis controlling for positive, extrapyramidal, and depressive symptoms, treatment group (standardized β?=??0.640) significantly predicted changes in primary negative symptoms. The side effect profile did not differ significantly between the two groups.

Conclusion

Tropisetron add-on to risperidone improves the primary negative symptoms of patients with chronic stable schizophrenia.  相似文献   
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Here, we present a 20-year-old man who presented with painful inguinal and femoral masses. He gave a history of sexual contact with a mare 14 days before his recent illness. He was diagnosed with lymphogranuloma venereum based on the histopathological findings and a high titre of IgG (1:1400).  相似文献   
8.

Background:

Polyethylene glycol (PEG) is often considered as the first-line treatment for functional constipation in children. Descurainia sophia (L.) Webb et Berth (D. sophia) is a safe recommended medicine in Iranian folk and Traditional Persian Medicine for the treatment of constipation.

Objectives:

To clinically compare D. sophia with PEG 4000 (without electrolyte) in pediatric constipation and to assess its efficacy and side effects.

Patients and Methods:

120 patients aged 2 - 12 years with constipation for at least 3 months were included in an 8 weeks lasting randomized controlled trial within two parallel-groups. Children received either PEG, 0.4 g/kg/day, or D. sophia seeds, 2 grams (for children aged 2 - 4 years) and 3 grams (for those aged > 4 years) per day.

Results:

A total of 109 patients completed the study (56 in D. sophia and 53 in PEG group). At the end of the study, 36 (64.3%) patients in D. sophia group and 29 (54.7%) in PEG group were out of Rome III criteria (P = 0.205). Median weekly stool frequency in 0, 1, 2, 3 weeks of the treatment was found to be 2, 5, 5, 5 in D. sophia and 3, 4, 4, 5 in PEG group (P = 0.139, 0.076, 0.844, 0.294), respectively. The number of patients who suffered flatulence was less (5, 8.9%) in D. sophia group as compared to PEG group (6, 11.3%) at the end of the trial (P = 0.461). D. sophia taste was less tolerated.

Conclusions:

D. sophia is introduced as a cheap and available medication which can be applied as a safe alternative to conventional PEG in the management of pediatric chronic functional constipation.  相似文献   
9.
Since melatonin receptors are present in the intestines, the possibility that this hormone may affect intestinal motility has been studied in the rat. Sprague-Dawley male rats were given a carmine cochineal powder meal and were injected intraperitoneally with 1, 10, 100, or 1000 g/kg melatonin. Sixty minutes after treatment, intestinal transit was found to be faster in animals treated with small doses of melatonin (1 or 10 g/kg) than in saline-injected controls. This effect, however, appear to be clearly reversed with 100 or 1000 g/kg melatonin. In fact, these doses of the hormone reduced intestinal transit in rats. The nonselective melatonin receptor antagonist, luzindole (administered intraperitoneally in a dose of 0.25 mg/kg, 15 min prior to melatonin injection) totally prevented the accelerating effect of melatonin (10 g/kg) on intestinal transit. Luzindole per se failed to affect gut motility. Injection of the reversible acetylcholinesterase inhibitor and cholinergic agent, neostigmine, accelerated intestinal transit but failed to influence melatonin effect on this parameter. In contrast, intraperitoneal injection of the muscarinic receptor antagonist atropine delayed intestinal transit per se but did not reduce the stimulating effect of melatonin on this parameter. Intestinal myoelectrical recording revealed that intestinal myoelectrical activity was increased by intraperitoneal injection of melatonin (10 g/kg). Administration of luzindole totally prevented melatonin-induced increase of intestinal myoelectrical activity. These results indicate that melatonin may affect intestinal motility in rats when administered in small doses. This effect might be mediated by melatonin receptors in the intestines, although the involvement of central receptors for the hormone is also possible.  相似文献   
10.
Achieving adequate pulpal anesthesia in mandibular teeth is always a challenge. Supplementary injections and using drugs in combination are some methods implemented to overcome this hurdle. In this randomized clinical trial, use of meperidine in conjunction with lidocaine in intraligamentary injection did not exhibit significant improvement in anesthesia.Key Words: Periodontal ligament, Meperidine, Irreversible pulpitis, Dental anesthesiaThe failure rate of the inferior alveolar nerve block (IANB) in some experimental studies has been reported up to 75%.14 This lack of success has even increased to a maximum of 81% in some recent studies.57 To overcome this shortcoming, dental clinicians have actively sought measures to improve the patients'' anesthesia during different dental procedures. Apart from the anatomical variations mentioned in the applied anatomy of injections,8 several authors have attempted to modify the anesthetic technique,912 and others have compared different anesthetic agents13 or their concentrations14 to improve their efficacy.Activating the opioid receptors peripherally in inflammatory conditions has become a new trend in research to manage postoperative pain.15 Synergy between local anesthetics and opioids has become an interesting field of research recently.16 Opioids are frequently added to local anesthetics in a variety of surgical procedures, eg, intrathecal application for minor surgery.17 Meperidine or its derivatives, eg, pethidine (meperidine chloride) or norpethidine (Pethidine Intermediate B) are agonists of μ-opioid receptors, which block the pathway of pain signals to the trigeminal nucleus. They also activate peripheral opioid receptors and block sodium channels.1722 Despite controversy regarding the use of meperidine as an anesthetic,22 recent studies have demonstrated its benefits over prilocaine in arthroscopy with local anesthesia,16 nasal packing removal,23 etc.However, only a few studies have investigated the dental anesthetic efficacy of such combinations.24,25 The effect of the addition of meperidine to lidocaine in IANB for pain management in normal teeth24 and also in teeth with irreversible pulpitis25 has been studied. The aim of our study was to compare the efficacy of local anesthetics with and without meperidine for intraligamentary supplemental injection for teeth with irreversible pulpitis. Our null hypothesis stated that the addition of meperidine to standard lidocaine with epinephrine does not improve the efficacy of supplemental intraligamentary anesthesia in teeth with symptomatic irreversible pulpitis. The specific objectives were to randomly allocate volunteers with complete soft tissue anesthesia following an IANB, yet having positive pulp response, into 2 groups, and then compare the efficacy of lidocaine with epinephrine plus meperidine with that of lidocaine with epinephrine plus an equal volume of sterile water for supplemental periodontal ligament anesthesia.  相似文献   
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