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81.
Previously we reported that lithium chloride (LiCl) potentiates tumor necrosis factor (TNF)-mediated cytotoxicity in vitro and in vivo. Here, using a murine normal skin model, it is shown that a subcutaneous injection of TNF plus LiCl induces acute dermal and subcutaneous inflammation and necrosis. Histology showed a marked initial dermal and subcutaneous neutrophil infiltrate by approximately 2 hours, followed by a predominantly mononuclear infiltrate by 24 hours, which remained present for several days. Tumor necrosis factor or LiCl alone induced negligible inflammation, disappearing after 6 hours; furthermore there was never necrosis or ulceration of the overlying skin in case of single-agent application. In vitro studies showed that the combination of TNF and LiCl, but not either agent alone, was directly cytotoxic to fibroblastic cells of murine skin. No inflammatory infiltration was visible in tumors treated intratumorally or perilesionally with TNF plus LiCl, although the latter treatment resulted in a perilesional leukocyte infiltration. Furthermore the combination of TNF and LiCl had no effect on macrophage cytotoxicity to L929 tumors.  相似文献   
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It is essential that children on prolonged parenteral nutrition for anatomical or functional loss of small bowel should enjoy a quality of life which is as normal as possible. Their return home is a major factor in this. Over the past 8 years, 112 children were able to remain at home on cyclic parenteral nutrition. Forty-nine of them are no longer on home parenteral nutrition (HPN), 45 are still on HPN, and 18 have died. Growth and quality of life were good in most cases. Most of the complications were from infection, 1 septicaemia per 594 days on HPN. In the light of these results, HPN seems to be the best option for children requiring prolonged parenteral nutrition, although it can only be considered within the framework of a specialized centre, which ensures patient follow-up, and provides the logistical support required for this high-technology treatment.  相似文献   
83.
Plant foods have been associated inversely with colon cancer. Since amajor focus of this study was to identify components of plant foods whichmay account for their association with colon cancer, nutrients which arecommonly found in plant foods also were evaluated. A population-basedcase-control study was conducted in Northern California, Utah, and the TwinCities area of Minnesota (United States). Complete data were available frominterviewer-administered questionnaires on 1,993 cases and 2,410 controls.Higher intakes of vegetables (for highest relative to lowest quintile ofintake) were associated inversely with colon cancer risk: the odds ratio(OR) was 0.7 for both men (95 percent [CI] confidence interval = 0.5-0.9)and women (CI = 0.5-1.0). Associations were stronger among those withproximal tumors. Total fruit intake was not associated with colon cancerrisk although, among men, higher levels of whole grain intake wereassociated with a decreased risk (OR = 0.6, CI = 0.4-0.9 for older men);high intakes of refined grains were associated with an increased risk (OR =1.5, CI = 1.1-2.1). Dietary fiber intake was associated with a decreasedrisk of colon cancer: OR = 0.5 (CI = 0.3-0.9) for older men; OR = 0.7 (CI =0.4-1.2) for older women; OR = 0.6 (CI = 0.4-1.0) for men with proximaltumors; OR = 0.5 (CI = 0.3-0.9) for women with proximal tumors. Othernutrients, for which plant foods were the major contributor - such asvitamin B6, thiamin, and niacin (women only) - also were associatedinversely with colon cancer. Neither beta-carotene nor vitamin C wasprotective for colon cancer. Adjustment of plant foods for nutrients foundin plant foods or for supplement use did not appreciably alter the observedassociations between plant foods and colon cancer.  相似文献   
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There have been many recent advances in the diagnosis and management of children with retinoblastoma. Regarding diagnosis, the judicial use of ancillary studies, particularly B-scan ultrasonography, has been instrumental in supplementing the diagnosis when opaque media preclude a clear view of the underlying neoplasm. Computed tomography and magnetic resonance imaging are important in the early detection of associated pinealoblastoma, which occurs as part of the recently described syndrome of "trilateral retinoblastoma." With regard to management, the technique of enucleation continues to improve and the scleralized hydroxyapatite implant is now available to provide a better cosmetic appearance and better motility of the artificial eye. Methods have been described for harvesting fresh tumor tissue immediately after enucleation for special DNA studies. Recent reports have documented a decreasing frequency of enucleation and an increasing tendency to use eye-preserving methods of management. Plaque radiotherapy, which provides more localized irradiation to the specific tumor, is gradually supplanting external beam irradiation for localized retinoblastoma that does not exhibit extensive vitreous seeding. The indications and contraindications for cryotherapy and photocoagulation have been more clearly delineated. The role of chemotherapy is being evaluated in the treatment of primary retinoblastoma and for metastatic disease. New breakthroughs in genetic research are being applied to clinical genetic counseling. The prognosis for life and for preservation of vision has improved greatly in recent years.  相似文献   
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OBJECTIVES: Most surveillance and research efforts focus on severe violence, especially on homicides. Because less extreme forms of violence may be precursors to more extreme forms, the authors analyzed data from a national survey to describe the extent of nonfatal physical violence in the US. METHODS: The authors generated weighted national estimates from responses to a random-digit-dialed telephone survey. Respondents were asked if they had been "hit, slapped, pushed, or kicked by another person or hit with an object or weapon" in the preceding 12 months. Respondents were also asked how many times such incidents had occurred and, for the last such episode, their relationship with the perpetrator, whether they had been injured, and, if so, whether they had sought medical treatment. RESULTS: The authors estimate that approximately 15 million people, or 8% of the US adult population, experienced nonfatal physical violence, as defined for this study, during a 12-month period. Male gender, the 18-24-year-old age group, never having been married, being out of work or a student, and heavy drinking were associated with a higher likelihood of being assaulted. An estimated 75% of assaults were by a known person and 26% by a stranger. Women were more likely than men to be assaulted by current or former intimate partners; men were more likely than women to be assaulted by strangers. An estimated 18% of incidents resulted in injuries, and an estimated 7% required medical attention. CONCLUSIONS: Nonfatal physical violence is fairly common in the US and may lead to more than one million medical encounters each year.  相似文献   
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The distribution of secretoneurin (SN), a peptide derived from secretogranin II (SgII), in the coeliac ganglion, the splenic nerve and the spleen was examined by immunohistochemistry. In the ganglion, SN immunoreactivity (IR) was unevenly distributed. Positive nerve terminals densely surrounded some postganglionic perikarya in which also intense SN-IR was present. In the crushed splenic nerves, intense immunoreactivities appeared proximal (but to a less extent also distal) to the crush of the nerve. Analysis by cytofluorimetric scanning (CFS) demonstrated that SN-IR and neuropeptide Y immunoreactivity (NPY-IR) were predominant in the axons proximal to the crush representing anterogradely transported components. Using radioimmunoassay (RIA) we demonstrated that upon electrical stimulation (10 Hz, 1 min) of the splenic nerve, significant amounts of SN-IR (64.2+/-2.3 fmol) were released together with NA (4. 1x106+/-0.2 fmol) and NPY (330.0+/-7.2 fmol) from the isolated perfused porcine spleen. To evaluate the processing of SgII in sympathetic neurons, boiled tissue extracts (coeliac ganglia and splenic nerve) and boiled spleen perfusate (used as a suitable source for vesicle derived peptides) were analysed by gel filtration chromatography followed by SN-RIA. In all cases immunoreactivity was present solely as SN, indicating that SgII was fully processed to the free peptide. The evidence that SN is transported to the nerve terminals and is released from the porcine spleen upon nerve stimulation, suggests that it may modulate adrenergic neurotransmission and may also play a role in the neuroimmune communication.  相似文献   
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