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101.
Simian immunodeficiency virus (SIV)-specific CD8+ CTL were isolated from blood, cerebrospinal fluid, and brains of rhesus macaques infected i.v. with SIV. CTL were found as early as 1 wk postinfection and their appearance correlated with a decrease of viral Ag (p27) found in the blood. CTL isolated from cerebrospinal fluid and/or brain often recognized different viral proteins than CTL isolated from blood, suggesting either a unique migratory pattern to the central nervous system or a difference in activation/retention of lymphocytes in these compartments.  相似文献   
102.
The application of duplex ultrasonography in the evaluation of lower extremity arterial occlusive disease and in graft surveillance has enhanced significantly the vascular surgeon's diagnostic armamentarium. With continued refinements in gray scale image resolution, color flow, and spectral analysis, color duplex ultrasonography eventually will replace angiographic evaluation in carefully selected patients as the primary pre-interventional testing modality.  相似文献   
103.
The role of nitric oxide in inflammatory responses to substance P and other mediators of inflammation was examined in rat skin microvasculature in a blister base raised on the hind footpad. Superfusion of substance P (1 microM) over the blister base caused an increase in plasma extravasation and a vasodilator response which was not maintained. N(G)-Nitro-L-arginine (100 microM), an inhibitor of nitric oxide biosynthesis, attenuated vasodilatation and plasma extravasation due to substance P. The inactive isomer N(G)-nitro-D-arginine was without effect. Neurokinin A (1 microM), 5-hydroxytryptamine (1 microM), ATP (50 microM) and vasoactive intestinal polypeptide (1 microM) elicited vasodilation, which for vasoactive intestinal polypeptide was maintained even after washout. 5-Hydroxytryptamine and neurokinin A, but not ATP or vasoactive intestinal polypeptide, significantly increased plasma extravasation. Vasodilatation to neurokinin A, 5-hydroxytryptamine and ATP, and the increase in plasma extravasation due to neurokinin A and 5-hydroxytryptamine were unaffected by N(G)-nitro-L-arginine (100 microM), whereas vasodilation due to vasoactive intestinal polypeptide was significantly attenuated. These findings suggest that in rat skin microvasculature in vivo, nitric oxide is involved in vasodilator responses due to substance P and vasoactive intestinal polypeptide, and plasma extravasation due to substance P, but does not contribute significantly to vasodilatation induced by neurokinin A, 5-hydroxytryptamine or ATP, or the plasma extravasation induced by neurokinin A or 5-hydroxytryptamine.  相似文献   
104.
Considerable progress has been made in recent years in understanding the biology of NK cells. NK cells are no longer 'null cells', but express an array of functionally important molecules with which they mediate and regulate their cytolytic activity and the cytokines they secrete. Activation and proliferation of NK cells in influenced by cytokines produced by activated monocytes (IL-15, IL-12, IL-10) and activated T cells (IL-2). This paper reviews the phenotype and effector functions of NK cells, their tissue distribution, and evidence that NK cells proliferate in vivo as part of productive or pathologic consequences of immunity.  相似文献   
105.
BACKGROUND: Surgeons are often called upon to perform pancreaticoduodenectomy for either suspicion of malignancy or symptoms due to benign disease. Perioperative morbidity and mortality following pancreaticoduodenectomy have decreased markedly over the last 2 decades. In response, many surgical centers advocate expanding the indications for pancreaticoduodenectomy to include lesions other than periampullary carcinoma. PATIENTS AND METHODS: A retrospective review of medical records for 108 patients undergoing pancreaticoduodenectomy for benign disease at The Johns Hopkins Medical Institutions over 100 months was completed. The subset of patients with a histopathologic diagnosis of chronic pancreatitis was identified and compared with patients undergoing pancreaticoduodenectomy for other benign conditions. RESULTS: The mortality rate for the present series was less than 1%. Perioperative complications, the majority of which were self-limited, occurred in 51% of patients. The most common complication was delayed gastric emptying. Pancreatic anastamotic leak occurred in 18% of patients and developed significantly more frequently in patients with benign diseases other than chronic pancreatitis (31% versus 8%, P < 0.05). CONCLUSION: Among appropriately selected patients, the rates of perioperative mortality and serious morbidity are low, and concerns about mortality and morbidity should not prevent an aggressive approach to surgical resection in patients with benign disease.  相似文献   
106.
Pyoderma gangrenosum (PG) is a rare, poorly understood skin disease that occurs in all age groups. Less than 0.4% of patients are infants and represent a diagnostic challenge as early lesions may resemble other skin disorders. Here we report for the first time three siblings affected with PG all presenting during infancy. Unlike the older age group, the ulcers spared the legs but involved the buttocks, thighs and perianal area in all the infants. Conclusion: This is the first reported family with PG affecting three siblings suggesting autosomal recessive inheritance. The diagnosis may be more difficult in infants due to absence of underlying associated disorders and the tendency of the lesions to appear in areas where infants frequently have other dermatoses. PG characteristically involves the buttocks, thighs and perianal area and spares the legs.  相似文献   
107.
The licensing of interferon beta-1b dramatically changed the treatment of multiple sclerosis (MS) in the United States. Although it was the first therapeutic agent shown to affect the natural course of the disease, interferon beta-1b is not appropriate for all patients and is far from being a cure. Several other promising therapies now under study include immunosuppressive and immunomodulatory drugs to limit inflammation; oral administration of myelin to induce tolerance; monoclonal antibodies designed to deliver targeted immunotherapy; potassium channel blockers to facilitate conduction along demyelinated axons; and glial growth factors to promote remyelination. Clinical trials of potential therapeutic agents have proliferated in the past decade in conjunction with rapid advances in our understanding of the immunologic basis of MS. Some investigational therapies are associated with problematic toxicities, others benefit only a minority of patients, and many are still in the early stages of development. Nevertheless, because current therapeutic options are limited, and because the history of MS therapy is one of disappointment and frustration, it is essential that legitimate, scientifically based advances be widely disseminated to the neurologic community. This article reviews some of the most promising current and investigational therapies for MS.  相似文献   
108.
Children with pelvic fractures usually are polytraumatized. Concomitant abdominal and pelvic injuries are not uncommon. Medical records and X-rays of 54 children, in which a pelvic fracture was diagnosed at our institution from 1974-1993, were reviewed. Children ages < or = 16 years and treated as in-patients were included in this study. The fractures were classified according to the AO-Classification. 47 patients (87.0%) had concomitant injuries. The mean Polytrauma Score was 23.7 (mean Injury Severity Score 30.5). Nine Children sustained an open pelvic fracture with rectal and/or vaginal tear. 15 genitourinary lesions were found in 13 children. 18 patients underwent laparotomy. A large pelvic/retroperitoneal hematoma was found in 11 cases. There were 7 liver lacerations, 7 splenic injuries, 2 mesenteric tears, 2 kidney injuries and 1 small bowel lesion. Eight children (14.8%) died with 5 of them due to retroperitoneal or/and abdominal bleeding complications. A recent follow-up examination (81.8%) with a mean follow-up of 11.3 years showed that long-term morbidity usually was attributed to pelvic concomitant injuries.  相似文献   
109.
The relationship between the prognosis and age of patients with gastric cancer is controversial. To evaluate whether there is a biological characteristic specific to the age of patients, we examined the clinical characteristics of patients with gastric cancer with special reference to their age. Based on a prospective database, a retrospective study of 419 patients who underwent radical gastrectomy for cure in the past 6 years was conducted. Clinical characteristics including gender, gross appearance of the tumour (Borrmann's classification, tumour location), histopathology (depth of tumour invasion, lymph node status, Lauren's classification and degree of tumour cell differentiation) and TNM tumour stage were analysed in six different age groups (< 39, 40-49, 50-59, 60-69, 70-79, > 80 years). The mean age of the 419 patients was 64.6 years (range from 26-91) and the peak age incidence of gastric cancer (46.3%) was in the 60-69 year old age group. The male: female ratio was 4.6:1 on the whole and male gender predominated at ages > 60. The proportion of diffuse type tumours (68.4%) by Lauren's criteria in the young age group (< 39 yrs) decreased with age (25% in the > 80 years group; P < 0.001). Similarly, the proportion of poorly-differentiated tumours (89.5%) in the young age group (< 39 yrs) decreased with advancing age (P < 0.001). These findings suggest that both diffuse type and poorly-differentiated tumours predominate in younger patients and, without considering the factor of delay in diagnosis, may explain the poorer prognosis demonstrated in younger patients.  相似文献   
110.
A two-dimensional finite element model was constructed to analyze the simulated mechanical behavior of a cantilevered fixed partial denture. The variations of the models were made by altering the degree of bone support, the number of splinted abutments, and the length of the pontics. High stress concentrations were observed around the connectors of the fixed prosthesis and the tooth closest to the cantilever. Reduced bone support increased the deflection and stress concentrations. There was reduction in displacement and stress concentration when the teeth were splinted together. To improve the prognosis of the fixed partial denture cantilever, the number of abutments should be increased and the number of pontics decreased.  相似文献   
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