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1.
BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
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The use of a school backpack is one of the possible causes of back pain in children. Oxygen consumption ( ), pulmonary ventilation, and heart rate (f c) were measured in 35 pre-pubertal subjects [17 girls and 18 boys, mean (SD) age 11.3 (0.6) years]. They took part in a four-step experiment: (1) standing for 5 min, (2) walking at 3 km·h–1 for 7 min, (3) walking at 3 km·h–1 for 7 min carrying a school backpack weighing 8 kg, and (4) walking at 7 km·h–1 for 5 min with no load. The occurrence of back pain in the last 2–3 years and during the last 15 days was assessed for the subjects by means of a questionnaire. Mean (SD) standing was 215 (45) ml.min–1 during walking at 3 km·h–1, 503 (101) ml.min–1 during walking without a load, and increased to 541 (98) ml.min–1 during walking with a load (P<0.01). Carrying a backpack increased f c only minimally. The energy cost of walking at 3 km.h–1 without the backpack was 10.0 (2.0) ml O2 .m–1, and with the backpack was 10.8 (1.9) ml O2 .m–1 (P<0.01). The net energy cost of locomotion was 0.129 (0.032) ml.kg body mass–1.m–1 for the unloaded condition and slightly lower, at 0.123 (0.025) ml.kg body mass–1.m–1 during loaded walking (P<0.05). Ventilation did not change significantly between unloaded and loaded conditions. When the data were assessed according to the occurrence of back pain, the f c/ slope was significantly lower in children without back pain, even though the net energy cost of locomotion was similar. Overall, these data suggest that the cardiovascular effortrequired for locomotion while carrying a backpack is minimal. However, fatigability and back pain are more likely to take place in less physical performing subjects. Thus, the occurrence of back pain in schoolchildren during locomotion while carrying a backpack may improve with an improvement in their level of fitness. Electronic Publication  相似文献   
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Hundreds of thousands of tourists visit Bali each year, many of whom pay to have sex with local residents. Kuta, one of Bali's major tourist resort towns, has manifested an higher demand for condoms than other studied areas in Indonesia. Such demand is laudable in the context of a growing HIV/AIDS epidemic, but demand must encounter supply to be worthwhile. The Citra Usadha Indonesia Foundation (YCUI) has been conducting outreach education in Kuta and other areas of Bali since February 1992. Over that time, outreach workers have found that street youths' and prostitutes' main sources for condoms, pharmacies, supermarkets, and YCUI outreach workers, are either closed or potentially unavailable at night, when most sexual transactions occur. Pharmacies and supermarkets close at 10 pm. YCUI therefore initiated a six-month condom distribution program in 1994 to encourage the approximately 150 street vendors working in Kuta to sell condoms. Street vendors who enrolled in the program were provided with a monthly supply of 30 free condoms for the period of six months and invited to sell them to the public at whatever price the market set. Concurrently, YCUI promoted condom sales and increased awareness of the new condom source through social marketing techniques and their network of outreach workers. After six months, 122 vendors had participated in the program selling 10,255 condoms. Vendors were able to sell more and more condoms as the program progressed. A final evaluation will be conducted October 1994 to determine how many vendors still sell condoms now that the free supplies have been discontinued.  相似文献   
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BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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An insufficient future liver remnant(FLR)is associated with post-hepatectomy liver failure.Associating liver partition and portal vein ligation for stage hepatectomy(ALPPS)has been shown to be effective for the induction of rapid FLR hypertrophy so as to improve the resectability in patients with insufficient FLR.We hereby report our experience of this novel approach for a 6-year-old patient with hepatoblastoma.Computed tomography showed a hepatoblastoma measuring12.5 cm×9.9 cm×11.7 cm in the right liver(Couinaud segmentⅣ,ⅤandⅧ).Volumetric assessment of the FLR i.e.,left lateral section was 112.6 mL i.e.,21.2%of the estimated total liver volume.In view of the small-for-size FLR,ALPPS was contemplated.An anterior approach was adopted for the in-situ parenchymal split without mobilisation of the right liver.FLR volumetry on the seventh postoperative day was 160.7 mL,which represented a 46.1%gain in volume,and a FLR/ESLV ratio of 30.2%.A right trisectionectomy was performed on the eighth postoperative day.Postoperative recovery was uneventful.Patient was discharged on day 16 after the first operation.To our knowledge,this was the first report that showed the applicability of ALPPS to a paediatric patient.  相似文献   
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Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
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Klock  JC; Boyles  J; Bainton  DF; Stossel  TP 《Blood》1979,54(6):1216-1229
We have investigated the effects of mechanical elution of neutrophils from nylon-wool fiber (NWF) using the scanning electron microscope and biochemical analysis of elution fractions. We have determined that mechanical removal of neutrophils from nylon-wool fiber disrupts neutrophils adherent to nylon-wool fiber and augments release of granules, release of peripheral cytoplasmic fragments, and release of lactic dehydrogenase, a soluble cytoplasmic enzyme. Mechanical shearing of the adherent cell, and not adherence per se, causes the fragmentation. The extent of fragmentation is proportional to the NWF surface area available to neutrophils and is maximal at the temperature for optimal adherence and spreading. Agents that decrease cell spreading (n-ethylmaleimide and cold) diminish fragmentation. Cytochalasin B, an agent that destabilizes the neutrophil cortex, increases fragmentation. Fragmentation may be an important contributing cause of the abnormal morphology, function, and in vivo survival of nylon-wool-fiber procured human neutrophils. The prevention of fragmentation would appear to be necessary to insure the procurement of optimally functioning cells. Elution of NWF-adherent neutrophils in the cold might be a practical way to diminish neutrophil damage during clinical filtration leukapheresis.  相似文献   
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