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51.
According to the establishment of methods for the determination of PSM residues in vegetable drugs the authors tried to detect organo-chlorinated compounds, which are used in agriculture and industry thus becoming of interest for the quality control of vegetable drugs. In most of the cases the determination was carried out by liquid/liquid partition between acetonitrile/n-hexane in combination with the CC using florisil for sample purification and capillary GC with a methyl silicone rubber column. Some of the results required a confirmation using a Megabore D-608 column (J&W Scientific).  相似文献   
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The nutcracker esophagus, a primary motor disorder, is frequently associated with noncardiac chest pain. However, there are no data on whether its diagnosis, as in other esophageal motility disorders, is delayed. Since the disorder is frequently heralded by alarming symptoms such as chest pain and dysphagia, diagnosis should be made as soon as possible. In this study we assessed the diagnostic delay, if any, in patients with the nutcracker esophagus. Moreover, we were interested in whether the abnormalities described in the distal esophagus could also involve the entire viscus. Fifty-four subjects (age range 23–78 yr) with the nutcracker esophagus were assessed for clinical and manometric variables as an overall group and after dividing them into subgroups according to their symptoms. The manometric variables were compared with those obtained in 61 controls (age range 21–67 yr). Overall, a diagnosis of nutcracker esophagus was made after an average period of 36 ± 6 months, and surprisingly, this was not different in the various subgroups complaining of either chest pain, dysphagia, or both. Analysis of manometric variables showed that the mean amplitude of contractions was significantly higher in the patients' group at all esophageal body levels, even in the proximal portions. Again, there were no significant differences among the subgroups of nutcracker esophagus with respect to the symptoms. Notwithstanding the presence of alarming symptoms, such as chest pain and dysphagia, the nutcracker esophagus is diagnosed on average after 3 years from the onset of symptoms. Manometric assessment seems to confirm that this entity may indeed represent a primary esophageal motor disorder. The major dysfunction is due to an abnormal increase of contraction amplitude of the entire esophageal body.  相似文献   
54.
BackgroundCalcific coronary lesions can be so resistant to prevent symmetric stent dilatation with high risk of ISR/thrombosis. The aim of the current study is to evaluate the safety and efficacy of super high-pressure dilatation (>30-to-45Atm) using a dedicated NC-balloon (OPN, SIS-Medical-AG, Winterthur-Switzerland).MethodsWe retrospectively evaluated 326 consecutive undilatable lesions in which conventional NC-balloons failed to achieve adequate post-dilatation luminal gain. After the failed attempt an OPN-balloon was inflated up to achieve a uniform balloon expansion (maximal dilatation pressure of 45–50 Atm). Lesions were divided into two groups according to the final inflation pressure: Group-I: lesion responsive to 30-40Atm and Group-2:>40 Atm. Angiographic success was defined as residual angiographic stenosis<30% assessed by visual estimation with TIMI3-flow. Procedural success was defined as the achievement of angiographic success without any MACE.ResultsAngiographic success was achieved in 97.5%, procedural success in 96.6%; 53% of the lesions were responsive to a slower inflation pressure (Group I) while in the remaining 47%, the optimal expansion required a pressure > 40ATM (Group II). In 3 patients coronary rupture occurred after balloon inflation and was successfully treated with stent implantation with a final TIMI3-flow. The OPN alone was able to achieve adequate expansion in >90%. 0.9% days MACE were reported.ConclusionThe OPN-dedicated high-pressure balloon provides an effective and safe strategy for treatment of severe resistant coronary lesions.  相似文献   
55.
BACKGROUND: Available information on normal bowel habits was mainly gathered by means of telephone interviews or mailed questionnaires. AIMS: We undertook a prospective study to evaluate the defecatory habits in subjects perceiving themselves as normal concerning this function. SUBJECTS AND METHODS: A questionnaire (4-week diary with "yes-no" daily answers to six questions concerning bowel habits) was distributed to 204 subjects perceiving their defecation behaviour as normal. RESULTS: The completed questionnaire was returned by 140 subjects. No significant differences were found between sexes or age groups for any variable, even though straining at stool and feeling of incomplete and/or difficult evacuation showed a trend to increase with age. No subject had less than three bowel movements per week or more than three per day. The percentage of symptoms linked to an abnormal defecatory behaviour was well below 10%. Fifty-five percent of subjects reported at least one parameter of abnormal functioning; the most frequent was straining at stool and the rarer was the manual manoeuvres to help defecation. CONCLUSIONS: In normal subjects the prevalence of symptoms considered in Rome II criteria as part of an abnormal defecatory behaviour (in more than 25% of defecations) is well below 10%, manual manoeuvres are almost never used to help defecation, and the frequency of defecations is at least three per week.  相似文献   
56.
Loss of interstitial cells of Cajal network in severe idiopathic gastroparesis   总被引:12,自引:0,他引:12  
INTRODUCTION Gastroparesis syndrome is a clinical entity characterized by chronic nausea, epigastric discomfort and recurrent vomiting, in the absence of mechanical obstruction[1]. Gastroparesis may be either primary (idiopathic) or secondary, i.e. associ…  相似文献   
57.
In literature different cases of polyglandular autoimmune type II syndrome (PGA II) are reported, where Addison's disease is associated with gonadal insufficiency. The lack in the production of sexual steroids causes a severe postmenopausal osteoporosis. The case we report is related to a 38-year-old woman we met in 1988 and who was suffering from deep asthenia, cramps, cutaneous hyperpigmentation, nausea, vomiting, abdominal pain, weight loss and hypotension. The biochemical data were indicative for autoimmune adrenal failure. Between 1988 and 1997 the patient developed a progressive insufficiency of other endocrine glands, leading to the classic feature of PGA II. In 1998, this clinical status was complicated by a severe osteoporosis. We thought that the sudden decrease in the bony mineral density was due to the lack of the protective role played by adrenal gland androgens in postmenopausal osteoporosis. They would directly act on the bony tissue, independently from oestrogens peripheral conversion, thus producing a stimulant effect on the bone formation. A new therapeutical approach, in case of osteoporosis, is today represented by DHEA replacement therapy in women showing low hormone levels.  相似文献   
58.
During the winter season 2005/2006, measurements of small particulate matter were taken in 22 schools in southwest Germany. PM2.5 was measured gravimetrically. Laser particle counter (LPC) and condensation particle counter (CPC) were used to determine different particle fractions. The investigation included measurements inside (in classrooms) and outside of school buildings. During the whole investigation period continuous reference measurements were taken near the State Health Office in the city of Stuttgart. Information on building-specific data and traffic near the schools was collected via questionnaire. Although distances between the different schools and the location of the State Health Office building in Stuttgart in some cases exceeded 100 km, the concentration levels of particles > 0.3 microm measured by LPC near the different schools were similar to those measured in Stuttgart. The differences between the measurements in Stuttgart and at the other locations were smaller than the variation in time. In the winter season, the impaction of particulate matter was strongly influenced by specific weather conditions. Time resolution of measurements in classrooms showed variation in particle concentration depending on the type of building and indoor activities like cleaning or moving during breaks. Concentrations of very small particles in buildings and in ambient air measured by CPC were influenced by traffic emissions. The observed data give reason to assume that the influence of high traffic emissions to indoor particle concentration may have been overestimated. Furthermore, there is an urgent need for standardization of measurement protocols, sampling, and determination of indoor particulate matter. The classical gravimetric methods are less appropriate since they do not allow for a time resolution of measurements.  相似文献   
59.
AIMS: To study relationships between the number of pseudomelanosis coli cells and that of colonic enteric neurons and interstitial cells of Cajal, which are significantly reduced compared with controls in severely constipated patients. Pseudomelanosis coli is frequent in patients using anthraquinone laxatives. It is not known whether the prolonged use of these compounds damages the enteric nervous system in constipated patients. PATIENTS AND METHODS: The relationship between the number of pseudomelanosis coli cells and that of colonic enteric neurons (as well as that of apoptotic enteric neurons) and of interstitial cells of Cajal was assessed by histological and immunohistochemical methods in 16 patients with chronic use of anthraquinone laxatives undergoing surgery for severe constipation unresponsive to medical treatment. No relationship was found between the number of pseudomelanosis coli cells and that of enteric neurons (and that of the apoptotic ones), nor of interstitial cells of Cajal, in either the submucosal or the myenteric plexus. CONCLUSION: The use of anthraquinone laxatives, leading to the appearance of pseudomelanosis coli, is probably not related to the abnormalities of the enteric nervous system found in severely constipated patients.  相似文献   
60.

Background

Gut mast cells represent an important cell population involved in intestinal homeostasis and inflammatory processes. However, their possible role has not to date been investigated in colonic diverticular disease.

Aims

This study aims to evaluate colonic mast cells in patients undergoing surgery for diverticular disease.

Methods

Surgical resection samples from 27 patients undergoing surgery for diverticular disease (12 emergency procedures for severe disease and 15 elective procedures) were evaluated. The number of mast cells was assessed in the various layers by means of a specific antibody (tryptase) and compared with those evaluated in ten controls. In patients with mast cells degranulation, double immunohistochemistry, also assessing nerve fibres, was carried out. In addition, the presence of myenteric plexitis was sought.

Results

Compared with controls, the number of mast cells in diverticular patients was significantly increased, both as an overall figure and in the various layers of the large bowel. In patients in whom mast cells degranulation was present, these were always closed to nerve fibres. No differences were found between the two subgroups of patients with respect to the number and distribution of mast cells; however, all patients undergoing emergency surgery (but none of those undergoing elective procedures) had myenteric plexitis, represented by lymphocytic infiltration in 67 % and eosinophilic infiltration in 33 % of cases.

Conclusions

Patients with diverticular disease display an increase of mast cells in the large bowel. The presence of myenteric plexitis in those with complicated, severe disease, suggest that this could represent a histopathologic marker of more aggressive disease.  相似文献   
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