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51.
Engineering of a variety of rodent tumour cells to secrete either interleukin 2 (IL-2), or interleukin 4 (IL-4), has been demonstrated to reduce their tumorigenicity. However the mechanisms of action of secreted IL-2 and IL-4 have not been compared in a single rodent tumour. Here we demonstrate that the weakly immunogenic murine fibrosarcoma FS29 had reduced growth rate and in some cases was rejected by syngeneic animals, when modified to secrete either IL-2 or IL-4, but not IL-5. Immunohistochemical analysis of tumour nodules undergoing regression showed stimulation of a largely lymphocytic infiltrate by IL-2 and a macrophage and granulocyte infiltrate, with a small number of lymphocytes by IL-4. Indeed, secretion of low levels of IL-2 and IL-4 in combination resulted in optimal rejection, suggesting that the two cytokines might mobilise different and complementary effector cell mechanisms. Both IL-2 and IL-4-secreting cells failed to induce the rejection of admixed, unmodified FS29 cells. The loss of cytokine secreting cells from such admixtures occurred more rapidly for IL-2-secreting cells. Injection of IL-4-secreting, but not IL-2-secreting FS29 cells could protect mice from a delayed challenge with unmodified FS29 cells. These data suggest that IL-4 secretion stimulates the better long-term host anti-tumour response.  相似文献   
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BACKGROUND. Long-term use of nonsteroidal antiinflammatory drugs (NSAIDs) may lead to inflammation of the small intestine associated with occult blood and protein loss. The aim of this study was to investigate the prevalence and structural correlates of this enteropathy. METHODS. We examined the stomach, duodenum, and small intestine of 713 patients post mortem. Of these patients, 249 had had NSAIDs prescribed during the six months before death and 464 patients had not. All visible small intestinal lesions were removed for histologic examination, and specific etiologic factors were sought. The prevalence of nonspecific small-intestinal ulcers and ulcers of the stomach and duodenum was compared in the two groups of patients. RESULTS. Nonspecific small-intestinal ulceration was found in 21 (8.4 percent) of the users of NSAIDs and 3 (0.6 percent) of the nonusers (difference, 7.8 percent; 95 percent confidence interval, 5.0 to 10.6 percent; P less than 0.001). Three patients who were long-term users of NSAIDs were found to have died of perforated nonspecific small-intestinal ulcers. Ulcers of the stomach or duodenum were found in 54 (21.7 percent) of the patients who used these drugs and 57 (12.3 percent) of those who had not (difference, 9.4 percent; 95 percent confidence interval, 3.9 to 15.1 percent; P less than 0.001). CONCLUSIONS. Patients who take NSAIDs have an increased risk of nonspecific ulceration of the small-intestinal mucosa. These ulcers are less common than ulcers of the stomach or duodenum, but can lead to life-threatening complications.  相似文献   
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The most common cause of nail bed deformity is trauma, but other causes are infection, tumor, ischemia, or congenital anomalies. This article includes discussions of nonadherence, split nail, reconstruction of the eponychium, crooked and hooked nail, bony irregularity, pachyonychia, ischemic deformities, and absence of the nail. New problems are encountered daily and other deformities have no method of correction recorded in the literature. For these cases, we provide suggested treatments based on the anatomy and physiology of the nail.  相似文献   
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BACKGROUND: Changing trends in cataract extractions have resulted in a new category of bullous keratopathy: corneal decompensation after complicated extracapsular cataract extraction. These cases of bullous keratopathy are associated with rupture of the posterior capsule, vitreous loss, and significant intraocular inflammation at the time of the original complicated extracapsular cataract extraction. METHODS: The authors reviewed 14 consecutive cases of penetrating keratoplasty for bullous keratopathy in which posterior chamber intraocular lens implantation was supported by remnants of the posterior capsule and/or Soemmering's ring without suture fixation. All 14 patients had a history of complicated extracapsular cataract extraction with capsule rupture and vitreous loss. RESULTS: All 14 patients had clear, compact grafts without migration of the intraocular lens with a mean follow-up of 12.1 months. Vision improved in 93% of cases, and there was no significant worsening of glaucoma. CONCLUSIONS: Pseudophakic bullous keratopathy after traumatic extracapsular cataract extraction with an anterior chamber intraocular lens and aphakic bullous keratopathy after traumatic extracapsular cataract extraction are two relatively new clinical entities that present new intraocular lens management options. Bullous keratopathy after complicated extracapsular cataract extraction should be recognized as a distinct clinical entity. Intraocular lens implantation into the ciliary sulcus with Soemmering's ring and peripheral capsular support provide the advantages of a posterior chamber intraocular lens without the risk of iris or scleral sutures. The authors predict that bullous keratopathy associated with traumatic extracapsular cataract extraction will become one of the more common indications for penetrating keratoplasty.  相似文献   
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Studies describing sexually transmitted disease (STD) and human immunodeficiency virus (HIV) prevention practices of primary care physicians have relied on physician or patient reports. This study describes physician STD/HIV prevention practices as observed by unannounced simulated patient evaluators (SPEs). SPEs visited sixty-five primary care physicians. Each SPE portrayed a sexually active female, new to the area, requesting a consultation on STD prevention. One-third of the physicians in the study asked no risk questions, and over 80% failed to ask the SPE specifically about her sexual practices. Most physicians discussed the risks of STDs and HIV and covered basic recommendations (use condoms and know partners better); however, few physicians provided any individualized information or advice about safer sexual practices and the specifics of condom use, such as how to use them or what kind to use. These observations support the low rates of STD/HIV prevention indicated in physicians' self-report and further identify specific deficiencies in the thoroughness of their risk assessment and preventive counseling practices.  相似文献   
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The recent Confidential Enquiry (2000-2002) has emphasised 'emergency drills for maternal resuscitation should be regularly practised in clinical areas in all maternity units'. It was therefore planned to assess the knowledge of airway management and ventilation among obstetrics and gynaecology trainees in the Yorkshire Deanery (Training Region). Questionnaires were given to trainees attending the Modular Training Programme and were collected on the same day. A total of 71 questionnaires were collected which represents 62% of the 113 trainees in Yorkshire region. Replies were received from 39 registrars, 27 Senior House Officers (SHO), four Senior SHOs (SSHO) and one clinical fellow. MRCOG Part 1 was passed by 52% and 36% of trainees had MRCOG Part 2. A total of 69% of trainees did not know that chin lift opens the airway in some 70 - 80% of patients; 50% of trainees were not aware why jaw thrust is preferred over chin lift; 76% of the trainees knew the most common cause of airway obstruction in a patient with an altered level of consciousness--the tongue falls back and obstructs the pharynx ('swallowing the tongue'). Knowledge of the main cause of airway obstruction was good among obstetrics and gynaecology trainees, but their understanding of how to manage this was found to be relatively poor. Attendance at a local Basic Life Support course should be compulsory for obstetric and gynaecology trainees early in their career.  相似文献   
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