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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   
3.
Leavitt  SA; DeAngelo  AB; George  MH; Ross  JA 《Carcinogenesis》1997,18(11):2101-2106
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.   相似文献   
4.
Female sterilisation is an important component of National Family Welfare Programme. The target group is best motivated during the puerperium for such a procedure. However laparoscopic sterilisation which has got some distinct advantages, is not technically feasible at this time. The authors have used a technique where the advantages of cosmetic appearance, reduced post operative morbidity and reversibility can be conferred on the puerperal women.After trying out the method individually in some cases, a formal case control study design has been made and an evaluation study has been performed in 122 cases. The technique has been found to be cosmetically more acceptable, both at clientele and peer evaluation levels (p<0.001). Though all the four parameters of post operative morbidity have shown better results for the technique evaluated as against the conventional technique, statistical significance has been achieved in two of the parameters (p<0.05).KEY WORDS: Cosmetics, Female sterilisation, Post operative morbidity  相似文献   
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6.

Background  

Pulmonary dysfunction following cardiac surgery is believed to be caused, at least in part, by a lung vascular injury and/or atelectasis following cardiopulmonary bypass (CPB) perfusion and collapse of non-ventilated lungs.  相似文献   
7.

Background  

Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders.  相似文献   
8.

Objective:

Patients often reach the hospital late after passage of golden hours (initial 6 hours) after sustaining high-velocity injuries. The decision of internal fixation in Gustilo''s Type IIIA and IIIB fractures becomes a formidable challenge in patients reaching late. The purpose of the present study was to find out if internal fixation could be safely undertaken in these patients.

Materials and Methods:

Sixty-three patients, having 70 compound fractures (46 Type IIIA and 24 IIIB), which were internally fixed after 6h but within 24h after injury, were included in the present analysis. Follow-up ranged from 18 to 48 months with mean of 28 months.

Result:

Overall infection rate noted was (n = 11) 15.71% (8.7% in IIIA, and 29.16% in IIIB). The difference in deep infection rate between Type IIIA and Type IIIB was found to be statistically significant (P value < 0.01). Nonunion was seen in five fractures. Functional evaluation using Katenjian''s criteria, showed 62.85% (44 fractures of 70) good to excellent results.

Conclusion:

Satisfactory results may be obtained in Gustilo''s Type IIIA and IIIB fractures even if fixed after the golden period, provided strict protocol such as aggressive debridement, prophylactic antibiotic coverage, early soft tissue reconstruction and timely bone grafting is followed. The primary coverage of the wound is discouraged.  相似文献   
9.
To avoid the potential risks of allogeneic transfusion during total hip arthroplasty (THA), the use of preoperative autologous blood donation (PABD) has been utilized. We performed a retrospective chart review of 283 patients undergoing THA that either donated 1 U of autologous blood (188 patients) or did not donate autologous blood before surgery (95 patients) in order to investigate the difference in postoperative transfusion rate (autologous and allogeneic), the incidence of allogeneic transfusion, and the difference in cost of each protocol. In addition, the study compared transfusion rates in patients with and without preoperative anemia (hemoglobin (Hb) ≤ 12.5 g/dL). At 0.75 transfusions per patient versus 0.22 transfusions per patient, the PABD patients had a significantly higher overall transfusion rate. PABD significantly reduced the need for allogeneic blood in anemic patients (Hb ≤ 12.5 g/dL) from 52.6% to 11.8%. PABD did not have the same affect in nonanemic patients (allogeneic transfusion rate 5.7% versus 4.0%). The study demonstrated that nonanemic patients undergoing THA do not benefit from PABD, but it is effective for anemic patients.  相似文献   
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