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991.
992.
BACKGROUND: Almost all patients with acquired immunodeficiency virus syndrome will have gastrointestinal symptoms during the course of their illness. The high prevalence and complications of esophagitis are well documented. AIM: Graduate esophagitis; identify microorganisms like Candida sp, cytomegalovirus, herpesvirus and mycobacteria; identify by immunohistochemical staining viral agents cytomegalovirus, herpesvirus I, herpesvirus II, Epstein-Barr Virus, human papilloma virus and human immunodeficiency virus; verify how immunohistochemistry changes the profile of esophagitis; verify the association between the histological and endoscopical findings; verify the relevance of the number of fragments studied in the characterization of the histological agents. METHODS: We studied retrospectively esophageal biopsies in 227 patients with acquired immunodeficiency virus syndrome using hematoxylin and eosin, PAS (periodic acid of Schiff), Groccott and Ziehl-Nielsen stains and immunoperoxidase stains to detect opportunistic agents. Endoscopic aspects were studied. RESULTS: The non-specific esophagitis grade III, in the inferior third of the esophagus, was the most frequent type. Candida sp was the most frequent agent, followed by viruses cytomegalovirus, herpesvirus and mycobacteria. The presence of plaque and ulceration suggested the diagnosis of esophageal candidiasis and cytomegalovirus esophagitis. Immunohistochemical allowed the characterization of cytomegalovirus and of herpesvirus in those cases where other techniques could not achieve it, furthermore the cytomegalovirus was also found in histological normal cases, making the use of this technique advisable in routine diagnosis. The herpesvirus I was not found isolated but associated to herpesvirus II. We have not found immunoreactivity for the Epstein-Barr virus and the human immunodeficiency virus. The number of fragments does not seem to influence the detection of the etiologic agent. CONCLUSION: The endoscopic findings of plaques or ulcers are associated with candidiasis or cytomegalovirus esophagitis. Immunohistochemisty improved the diagnosis of viral infections. It is possible to detect cytomegalovirus infections in endoscopic and histologic normal cases.  相似文献   
993.
994.
Malignant mesothelioma of the peritoneum is a rare neoplasm with a rapidly fatal course. The median survival range is from 5 to 12 months in untreated cases with little improvement seen in patients receiving multimodality therapy. Although most cases occur in the fifth and sixth decades, peritoneal mesothelioma can be seen in any age group. Approximately 30% of all mesotheliomas arise solely from the peritoneum. Asbestos exposure, primarily of the crocidolite variety, has been implicated in the pathogenesis of this malignancy, as was established in South Africa in the 1960s. Half of reported cases have a history of asbestos exposure. The diagnosis of peritoneal mesothelioma is often delayed, in part because of the usually long latent period (peaking at 40-45 years from the time of initial exposure to asbestos) and because the common presenting symptoms of weight loss, usually with a full abdomen, malaise, and abdominal discomfort, are mild and nonspecific. This paper aim is to present a case report regarding a patient diagnosed with malignant peritoneal mesothelioma with an unpredictable evolution.  相似文献   
995.
996.
Stoma is a Greek word meaning mouth or opening. There are many types of surgical stomas and they may be raised on many areas of the abdominal wall. A stoma may be temporary or permanent, may be needed in any age group and may be sited on any part of the abdomen. The specific digestive pathology that could have as result of the surgical management a stoma is represented by colon, rectal and anal cancer, diverticular disease of the colon and rectum, Crohn's disease, ischaemic bowel, volvulus, trauma, Hirschprung disease, imperforate anus, fecal incontinence. This paper aim is to asses the management of fecal stomas and the necessity of a trained ostomy support team.  相似文献   
997.
Echocardiography commonly represents the diagnostic clue in neonatal heart failure (HF). Congenital heart diseases are the most frequent causes of HF in this age group. Arterio-venous malformations are the most common noncardiac causes of HF. Normal cardiac structural findings on echocardiography require further investigations in order to exclude other causes of HF. We present three male patients admitted in the interval 2003-2007 with neonatal HF, systolic murmur, cardiomegaly, normal cardiac structure on echocardiography and intracranial bruit. All three cases were diagnosed with vein of Galen aneurysmal malformation (VGAM) by head ultrasound. According to age and malformation type, different presentation patterns were noticed: early neonatal intractable HF mimicking aortic coarctation, postnatal HF stabilized by drug treatment, and chronic HF in a VGAM with tendency to spontaneous regression. Both head ultrasound and cranial auscultation are mandatory in newborns or infants with no cardiac primary cause of HF.  相似文献   
998.
BACKGROUND: Pulmonary rehabilitation can improve the functional capacity, but has a variable effect on the low fat-free mass (FFM) in patients with chronic obstructive pulmonary disease. HYPOTHESIS: Pulmonary rehabilitation would not affect catabolic drives such as systemic inflammation and also protein breakdown. METHODS: Patients (n = 40) were studied at the start of an 8-week in-patient pulmonary rehabilitation programme, at the end of the programme and 4 weeks later. FFM and functional capacity (quadriceps strength, handgrip strength and peak workload) were assessed. Pseudouridine (PSU) urinary excretion (cellular protein breakdown) and inflammatory status were determined. Healthy participants had a single baseline assessment (n = 18). RESULTS: PSU, (IL)-6 and soluble tumour necrosis factor (sTNF)alpha R75 were increased in patients compared with healthy participants, whereas FFM and functional capacity were reduced (all p < 0.01). PSU was inversely related to both FFM and skeletal muscle function. FFM and functional parameters increased with rehabilitation, but PSU and inflammatory status were unaffected. The gain in FFM was lost 4 weeks after the completion of rehabilitation (p < 0.01). CONCLUSION: The anabolic effect of pulmonary rehabilitation improved FFM, but it did not reverse the increased protein breakdown or systemic inflammation. Thus, on cessation of pulmonary rehabilitation the FFM gains were lost owing to a loss of anabolic drive.  相似文献   
999.
The carcinogenic activity of various nickel (Ni) compounds is likely dependent upon their ability to enter cells and elevate intracellular levels of Ni ions. Water-insoluble Ni compounds such as NiS and Ni(3)S(2) were shown in vitro to enter cells by phagocytosis and potently induce tumors in experimental animals at the site of exposure. These water-insoluble nickel compounds are generally considered to be more potent carcinogens than the water-soluble forms. However, recent in vitro studies have shown similar effects for insoluble and soluble Ni compounds. Using a dye that fluoresces when intracellular Ni ion binds to it, we showed that both soluble and insoluble Ni compounds were able to elevate the levels of Ni ions in the cytoplasmic and nuclear compartments. However, when the source of Ni ions was removed from the culture dish, the intracellular Ni ions derived from soluble Ni compound were lost from the cells at a significantly faster rate than those derived from the insoluble Ni compound. Within 10 h after NiCl(2) removal from the culture medium, Ni ions disappeared from the nucleus and were not detected in the cells by 16 h, while insoluble Ni(3)S(2) yielded Ni ions that persisted in the nucleus after 16 h and were detected in the cytoplasm even after 24 h following Ni removal. These effects are discussed in terms of whole body exposure to water-soluble and -insoluble Ni compounds and consistency with animal carcinogenicity studies.  相似文献   
1000.
Until now, existing data on the oral carcinogenicity of nickel substances have been inconclusive. Yet, the assessment of oral carcinogenicity of nickel has serious scientific and regulatory implications. In the present study, nickel sulfate hexahydrate was administered daily to Fischer 344 rats by oral gavage for 2 years (104 weeks) at exposure levels of 10, 30 and 50 mg NiSO(4).6H(2)O/kg. This treatment produced a statistically significant reduction in body weight of male and female rats, compared to controls, in an exposure-related fashion at 30 and 50 mg/kg/day. An exposure-dependent increase in mortality was observed in female rats. However, the overall study survival rate (males and females) was at least 25 animals per group (compliant with OECD guidelines) in the treated animals. Daily oral administration of nickel sulfate hexahydrate did not produce an exposure-related increase in any common tumor type or an increase in any rare tumors. One tumor type was statistically increased in a nickel sulfate-treated group compared to the study controls (keratoacanthoma in the 10 mg NiSO(4).6H(2)O/kg/day males), but there was no exposure-response relationship for this common tumor type. This study achieved sufficient toxicity to reach the Maximum Tolerated Dose (MTD) while maintaining a sufficiently high survival rate to allow evaluation for carcinogenicity. The present study indicated that nickel sulfate hexahydrate does not have the potential to cause carcinogenicity by the oral route of exposure in the Fischer 344 rat. Data from this and other studies demonstrate that inhalation is the only route of exposure that might cause concern for cancer in association with nickel exposures.  相似文献   
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