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31.
One hundred and forty-four patients with apparently benign gastric ulcer were endoscopically followed up in order to evaluate the outcome of the lesion. Particular attention was given to: (a) detect possible delay in diagnosing gastric cancer; (b) ascertain the frequency of association with epithelial dysplasia; (c) establish the role of markers, such as serum pepsinogen group I (PGI), and gastric juice CEA in predicting gastric ulcer evolution. Endoscopic and bioptic check-ups were carried out during the first year at 3, 6 and 12 months after endoscopic healing of the ulcer, and then at every symptomatic recurrence. Ten patients (6.9%) were found to present histological evidence of malignancy (within 3 months in six cases, between 6 and 12 months in three cases, and after 41 months in the rest). Four cases were early gastric cancers, and six had shown dysplastic changes of the mucosa at the edge or scar of the ulcer. Serum PGI levels were not significantly different in gastric cancer patients, while gastric juice CEA levels were sharply increased compared to those of gastric ulcer patients: nine out of ten patients had values above normal range. These data suggest that: (a) there may be some delay in diagnosing gastric carcinoma, and gastric ulcer patients should be controlled routinely more than once; (b) the presence of dysplasia indicates the need for prolonged follow-up, because of the high risk of association with or evolution into gastric cancer, and because of the higher number of early gastric cancer detections that this protocol allows; (c) further support in monitoring patients "at risk" may be afforded by gastric juice CEA determination.  相似文献   
32.
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.  相似文献   
33.
Schwannomas are neurogenic neoplasms rarely found in the sinonasal tract, where localization to the nasal septum is exceedingly rare (only 11 cases have been described in the western literature). We report the case of a 29-year-old white male with a schwannoma completely filling the left nasal fossa and arising from the bony part of the septum. A computer tomography (CT) scan and a biopsy suggestive of benign schwannoma were obtained before the lesion was removed by a degloving approach. The preoperative diagnosis of nasal septum schwannoma was confirmed. The patient is asymptomatic and without endoscopic evidence of recurrence 7 years after surgery. A review of the literature with particular emphasis on the clinical presentation, histological features, differential diagnosis and therapeutic options for such a rare lesion is included. Received: 11 June 1999 / Accepted: 10 February 2000  相似文献   
34.
Serine is an amino acid that is not transported from the placenta to the ovine fetus. Thus, fetal plasma serine levels may be controlled by flux through their relevant biosynthetic pathways. This study was designed to determine, in fetal sheep tissues, the ontogeny of the three key enzymes in the biosynthetic pathway for serine, the cytosolic (c) and mitochondrial (m) isoforms of serine hydroxymethyltransferase (SHMT), phosphoglycerate dehydrogenase (PGD), and phosphoserine aminotransferase (PSAT). PGD and PSAT activity did not vary during gestation in either liver (PSAT, 9.4 +/- 1.3 nmol/min/mg cytosolic protein; and PGD, 76 +/- 10 mU/mg protein) or placenta (PGD, 8.0 +/- 3.6 mU/mg protein). In the liver, cSHMT activity was low early in gestation (0.6 +/- 0.5 nmol/min/mg protein at 45 days), rose in the last one-third of gestation, and peaked in the newborn period (25 +/- 3 nmol/min/mg protein at 1 week of age). Hepatic cSHMT RNA levels parallel the activity pattern. Mitochondrial SHMT was stable throughout gestation and with low constant mSHMT RNA levels. In contrast, the kidney and placenta had high mSHMT and steady low cSHMT activity throughout gestation. These data support the possible role of SHMT in the fetal control of plasma serine levels. While cSHMT may contribute to fetal hepatic serine production, its activity pattern does not support a primary role in the control of fetal hepatic serine biosynthesis. In the placenta, mSHMT may be important for glycine production from serine.  相似文献   
35.
36.
Pharmacological activation of A(1) adenosine receptor with 2-chloro-N6-cyclopentyladenosine (CCPA) or mGlu3 metabotropic glutamate receptors with (2S,2'R,3'R)-2-(2', 3'-dicarboxycyclopropyl)glycine (DCG-IV) or aminopyrrolidine-2R, 4R-dicarboxylate (2R,4R-APDC) enhanced the release of nerve growth factor (NGF) or S-100beta protein from rat cultured astrocytes. Stimulation of release by CCPA and DCG-IV or 2R,4R-APDC was inhibited by the A(1) adenosine receptor antagonist 8-cyclopentyl-1, 3-dipropylxanthine and by the mGlu2/3 receptor antagonist (2S,1'S, 2'S,3'R)-2-(2'-carboxy-3'-phenylcyclopropyl)glycine (PCCG-4), respectively. Time-course studies revealed a profound difference between the release of S-100beta protein and the release of NGF in response to extracellular signals. Stimulation of S-100beta protein exhibited rapid kinetics, peaking after 1 h of drug treatment, whereas the enhancement of NGF release was much slower, requiring at least 6 h of A(1) adenosine or mGlu3 receptor activation. In addition, stimulation of NGF but not S-100beta release was substantially reduced in cultures treated with the protein synthesis inhibitor cycloheximide. In addition, a 6-8 h treatment of cultured astrocytes with A(1) or mGlu3 receptor agonists increased the levels of both NGF mRNA and NGF-like immunoreactive proteins, including NGF prohormone. We conclude that activation of A(1) adenosine or mGlu3 receptors produces pleiotropic effects in astrocytes, stimulating the synthesis and/or the release of protein factors. Astrocytes may therefore become targets for drugs that stimulate the local production of neurotrophic factors in the CNS, and this may provide the basis for a novel therapeutic strategy in chronic neurodegenerative disorders.  相似文献   
37.
This study aimed to clarify the structure and the etiological constituents of schizotypal disorder (SPD) by directly interviewing pairs of twins. A latent class analysis was applied to each individual's outcome for specified SPD items, such that each subject's phenotype could be redefined in terms of individual probabilities of class membership. Intraclass correlations were then calculated for each twin pair, and a standard univariate twin model applied. The best latent class analysis solution encompassed a model with four latent classes (three latent classes of SPD subjects, one of non-SPD). The intraclass correlations revealed a moderate to high heritability for two out of three SPD classes and for the modal class (a class composed of subjects that possessed a conditional probability of belonging to any of the SPD classes). Model fittings revealed considerable variation in the extent to which the different classes of SPD were influenced by additive genetic constituents or non-genetic factors. Although these data confirm the importance of genetic contributors in determining liability to SPD and the schizophrenia spectrum, they indicate that there is a relationship between psychometric multidimensionality and etiological heterogeneity in SPD.  相似文献   
38.
The aim of this study was to compare the efficacy of two doses of monthly intramuscular (i.m.) injections of fluphenazine decanoate in reducing self-harm behaviours in outpatients with histories of multiple suicide attempts. Fifty-eight patients who presented to a psychiatric emergency service after an attempted suicide and who had histories of multiple suicide attempts, were randomized to receive monthly i.m. injections of fluphenazine decanoate. Thirty patients received monthly 12.5 mg ('low' dose), and 28 patients received monthly 1.5 mg ('ultra low' dose) under double-blind conditions. DSM-III-R diagnoses were obtained on all patients using the Structured Clinical Interview for DSM-III-R-Patient Version (SCID-P) and SCID for DSM-III-R Personality Disorders (SCID-II). Outcomes were assessed by the Parasuicide History Inventory and the Abnormal Involuntary Movement Scale, collected monthly for 6 months. Patients had an average of six current Axis I and 2.6 Axis II diagnoses, with borderline personality (85%) and alcohol dependence (58%) occurring most frequently in the sample. Both the low dose and ultra-low dose groups showed a marked reduction in self-harm behaviours. For 'serious' self-harm behaviours, there was a trend for a greater effect of the low dose over the ultra-low dose group, however, the differences did not reach statistical significance. A survival analysis indicated that the presence of 'acute' stressors at baseline and female sex were risk factors for continuing (post-randomization) 'serious' self-harm behaviours, while younger age and the absence of concurrent general medical conditions were risk factors for all self-harm behaviours.  相似文献   
39.
40.
Neurophysiological investigations (EEG, ERG, VEP) were carried out in 13 patients with proven "mitochondrial myopathy". There were nine girls and four boys. Varied abnormalities were seen in the EEGs of all cases, and in one patient unusual repetitive bursts of irregular slow waves and spikes were observed. The ERG was abnormal in five of the 12 cases tested, while the VEP (flash) was definitely abnormal in six out of these 12 cases. These neurophysiological findings suggest some involvement of both the brain and the visual system. It seem therefore appropriate that this condition be considered a "mitochondrial disease" affecting many systems rather than only muscles.  相似文献   
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