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991.
Cancer is a heritable disorder of somatic cells: environment and heredity are both important in the carcinogenic process. The primal force is the “two hits” of Knudson’s hypothesis, which has proved true for many tumours, including renal cell carcinoma. Knudson et al. [1, 2] recognised that familial forms of cancer might hold the key to the identification of important regulatory elements known as tumour-suppressor genes. Their observations (i.e., that retinoblastoma tend to be multifocal in familial cases and unifocal in sporadic presentation) led them to propose a two-hit theory of carcinogenesis. Furthermore, Knudson postulated that patients with the familial form of the cancer would be born with one mutant allele and that all cells in that organ or tissue would be at risk, accounting for early onset and the multifocal nature of the disease. In contrast, sporadic tumours would develop only if a mutation occurred in both alleles within the same cell, and, as each event would be expected to occur with low frequency, most tumours would develop late in life and in a unifocal manner [3, 4]. The kidney is affected in a variety of inherited cancer syndromes. For most of them, both the oncogene/tumour-suppressor gene involved and the respective germline mutations have been identified. Each of the inherited syndromes predisposes to distinct types of renal carcinoma. Families with hereditary predisposition to cancer continue to provide a unique opportunity for the identification and characterisation of genes involved in carcinogenesis. A surprising number of genetic syndromes predispose to the development of renal cell carcinoma, and genes associated with five of these syndromes have been already identified: VHL, MET, FH, BHD and HRPT2. Few cancers have as many different types of genetic predisposition as renal cancer, although to date only a small proportion of renal cell cancers can be explained by genetic predisposition. Supported by an unrestricted educational grant from Pfizer.  相似文献   
992.
Our aim was to determine what parameters may be used to indicate an emergent endoscopy after foreign body (FB) ingestion and to ascertain how often FBs are found endoscopically. Demographic data, gastroesophageal antecedents, clinical and endoscopic data, and complications were obtained. We examined 122 patients endoscopically. The onset of symptoms was immediate after FB ingestion in 93% of patients. Dysphagia was the most frequent symptom (66%), with the pharynx the most frequent location of impaction (71%). Endoscopy confirmed the presence of FBs in 52% of patients. Extraction was performed in 78%. The immediate onset of symptoms, dysphagia, and the absence of pharynx localization of impaction were predictive indicators of a positive FB finding (p < 0.05), with diagnostic sensitivity of 86% and specificity of 63%. Upper endoscopy should be performed in all patients with FB ingestion, even though no FB was found in 48%.  相似文献   
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Portal hypertension frequently causes the appearance of porto-systemic shunts, such as esophageal varices and also, but with much less frequency, other atypical shunts known as ectopic varices. Despite their infrequency/rarity, ectopic varices can cause serious gastrointestinal bleeding. Intraabdominal adhesions, especially post-operative ones, promote their appearance. The therapeutic management of ectopic varices is initially the same as that for esophageal varices but surgical treatment is usually necessary as a diagnostic and therapeutic procedure.  相似文献   
995.
Volvulus of the colon mainly affects the elderly and early surgery, with high morbidity and mortality, is often required. The efficacy of endoscopic devolvulization as an alternative is evaluated herein. From January 1993 to April 1999, 25 patients diagnosed with volvulus of the colon were retrospectively reviewed. Endoscopic devolvulization was not performed in one patient who showed signs of necrosis but was carried out in the remaining 24. The mean follow-up was 35.3 months. In all patients the procedure was initially effective. After the first attempt, 9 of the 24 patients (37%) relapsed, 4 out of 7 (57%) after a second attempt and 2 out of 2 (100%) after a third attempt. No morbidity or mortality was associated with the endoscopy. Six patients underwent surgery. Of these, none relapsed but two presented complications associated with the surgery. Mean hospital stay of the patients undergoing surgery was 30.8 days and that of those undergoing endoscopic devolvulization was 9.1 days. We conclude that endoscopic devolvulizatio is an effective therapeutic option when the mucosa is viable, with a high percentage of initial success, few complications inherent to the technique and with the possibility of carrying out a maximum of two attempts in cases of relapse. In the majority of patients, this technique is a valid alternative to urgent surgery, which has higher morbidity and mortality and longer mean hospital stay.  相似文献   
996.
When we speak about AIDS, even today, we rarely associate it with the elderly. Nonetheless, nursing care reality demonstrates that AIDS cases are more numerous all the time inside this population group known as the third generation. We should not forget that sex is a personal experience that can be practiced at all ages, and is not limited only to the young, and that preventive measures are necessary in all situations. Therefore, it is interesting to share what these authors reflect about this topic; they refer to a real case. It will probably be necessary to change the established schemes and consider this age group to be one in need of information on the possibilities of contagion. It will also be essential to carry out faster diagnoses and to develop educational measures as well as continuing professional development procedures in order that the elderly be considered susceptible to suffer this disease and to improve the treatment provided to the elderly. AIDS does not discriminate. Therefore, we cannot discriminate either.  相似文献   
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