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991.
A 48-year-old Indian man swallowed a fish bone and presented 1 week later with dysphagia, following a single episode of fresh hematemesis. A barium swallow demonstrated a horizontal mucosal tear at the level of the aortic arch, and computed tomography (CT) showed mediastinal emphysema and a bleeding point medial to the left subclavian artery which appeared to be contained by a surrounding hematoma. Subsequently, he developed sudden massive hematemesis and collapsed. Despite emergency surgery, the patient died. At the postmortem examination, a 1.2-cm fistula tract was found connecting the esophagus to the left subclavian artery. This case report emphasizes that a diagnosis of arterio-esophageal fistula should be considered if a patient presents with fresh hematemesis and a recent history of foreign body ingestion.  相似文献   
992.
Infection with Helicobacter pylori, is one of the most prevalent infections world-wide, where approximately 50% of adults in the developed world and over 90% of inhabitants in the developing world are infected. Chronic infection with H. pylori is the cause of gastritis, peptic ulcer disease and is a risk factor for gastric adenocarcinoma. Recent studies have demonstrated the suitability of an immunization strategy in the prevention and treatment of H. pylori infection, and the potential for management of disease. Mucosal administration of purified recombinant sub-unit proteins of H. pylori, together with a mucosal adjuvant, has identified urease to be highly efficacious in prophylactic and therapeutic animal model studies, and show partial therapeutic activity in humans. Several other antigens are also effective, and the recent sequencing of the H. pylori genome has led to an intensive effort in antigen discovery. Other research has centered on the identification of novel approaches for delivery, and the immunological mechanisms underlying protective immunity. In this review, preclinical data and the results of early-stage clinical trials and directions for future research on Helicobacter vaccines are described.  相似文献   
993.
OBJECTIVE: To examine the characteristics of primary vesico-ureteric reflux (VUR) in young infants following prenatal hydronephrosis. PATIENTS AND METHODS: The study comprised 155 consecutive infants with VUR detected at a mean age of 8.7 weeks (SD 6.3). Reflux units (n = 236) were analysed for relationships between gender, severity of reflux, exposure to urinary tract infection (UTI) and the presence of focal and generalized types of kidney damage on imaging. Bladder wall thickness (from ultrasonography) was examined in comparison with a further group of 29 males without VUR. RESULTS: Male infants predominated (117 of 155, 75%); bilateral VUR affected the same proportion (52%) of males and females. Most kidneys exposed to VUR (158 of 236. 67%) were normal and of the 78 abnormal kidneys (57 without UTI), 53 showed generalized damage (only eight exposed to UTI) and 71 (91%) were associated with severe (grades IV and V) reflux that predominantly affected males (P < 0.001). Grade V reflux was almost exclusively a male disorder. Most female units (45 of 58, 78%) compared with 46% (82/178) of male units had mild (grades I to III) reflux that was independently associated with normal kidneys. The mean bladder wall thickness was significantly greater for males with VUR than for females with VUR and for males without VUR. CONCLUSIONS: Two distinct but not exclusive patterns of VUR were identified: (i) mild reflux associated with normal kidneys that affected most females and a proportion of males; (ii) severe reflux combined with kidney damage, most likely fetal in origin, that is almost exclusively a male disorder.  相似文献   
994.
995.
996.
Currently, upper gastrointestinal endoscopies are frequently performed for patients with various gastrointestinal symptoms. From time to time, lumps and bumps in the stomach are encountered on endoscopy. Four cases of gastric polypoid lesions are presented. The classification, differentiation, and management approach to these lesions are discussed. Although there is consensus that all gastric adenomatous polyps should be removed, as should gastric hyperplastic polyps that are symptomatic and/or bear dysplastic foci on forceps biopsy, controversy still exists over the management of asymptomatic gastric hyperplastic polyps that do not bear any dysplastic focus on forceps biopsies. Endoscopic ultrasonography (EUS) has a promising role in the evaluation of gastric submucosal polypoid lesions.  相似文献   
997.
BACKGROUND: Previous studies in which monoclonal antibodies (MoAbs) were used against different epitopes of human chorionic gonadotropin (hCG) demonstrated the presence of membrane-associated hCG and its subunits by cancer cells of different types and origins and by human embryonic and fetal cells. To elucidate the mechanism of action of a synthetic vaccine against hCG, experiments were conducted to determine the presence or absence of direct dose dependent cytolytic activity by hCG MoAbs, including those elicited by the vaccine. METHODS: Human adenocarcinoma cells from the uterine cervix (ATCC HeLa CCL 2.0) grown in defined media at 37 degrees C were treated for 2-3 days with different selected doses of each of 12 MoAbs directed against different epitopes of hCG. Three of these MoAbs were against three different epitopes of the synthetic hCGbeta vaccine. RESULTS: There was a direct dose dependent effect by a MoAb directed against the natural hCGbeta carboxy terminal peptide (CTP), by a MoAb directed against hCGalpha, and by one of the three MoAbs produced by the synthetic hCGbeta-CTP, which is the main component of the World Health Organization (WHO) vaccine being tested for fertility control and for cancer treatment or prevention. CONCLUSIONS: For the first time (to the authors' knowledge), these results show the existence of hCG MoAbs that have direct dose related cytotoxicity at 37 degrees C and explain the mechanism of action of the WHO anti-hCG vaccine.  相似文献   
998.
In the past decade, significant progress has been achieved in the battle against hepatitis B virus. In addition to the immunomodulating agents such as interferon-alpha and thymosin, many novel antiviral agents have been discovered, among which nucleoside analogues are the mainstay. New-generation compounds such as 3TC and famciclovir have shown promise in the treatment of patients chronically infected by this virus, and are on the line for approval. However, viral rebound after cessation of therapy still remains a major problem. Additionally, the reports on the drug resistance to these antiviral agents suggest that combination therapy will be the eventual strategy (Bartholomew et al., 1997; Tipples et al., 1996). Therefore, developments of safe and effective antiviral agents which do not cross-resist with currently available antiviral drugs are still much needed.  相似文献   
999.
1000.
Current theories and research about the etiology and treatment of psychotic disorders increasingly point to the importance of biological factors. Accompanying this shift in the etiological literature has been an accumulation of evidence indicating the need to move away from treatment modalities that make families of people with psychotic disorders feel culpable in the causation or perpetuation of their relatives' disorders. The current study reports the development of a reliable and valid scale to assess the extent to which practitioners have made this shift. It also reports two surveys, the findings of which imply grounds for concern about what many practitioners do when working with clients with severe and persistent mental illness and their families.  相似文献   
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