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PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats.  相似文献   
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Uterine rupture during labor, when it is in the immediate vicinity of the cervix, frequently extends transversely or obliquely. Usually the tear is longitudinal when it occurs in the portion of the uterus adjacent to the broad ligament. We report an unusual case of uterine rupture through posterior vaginal fornix of the posterior lower uterine segment.  相似文献   
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Summary A simple organ culture method for culturing embryonic skin was developed. A piece of skin with a part of the neural tube from mouse embryo (11 to 12 d) was placed on a 25 mm d membrane filter. The filter was folded to wrap the explant and inserted into glass tubing. The explant and filter in the glass tubing were placed in a rotating tissue culture tube containing 5 ml culture medium (Ham's F12 supplemented with 15 to 20% fetal bovine serum) and filled with a mixture of 95% air:5% CO2. In explants cultured for 6 d fully differentiated melanocytes were observed in the epidermis.  相似文献   
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INTRODUCTION: One of the most common and important side effects of 5-fluorouracil (5-FU) is mucositis with ulcerations in the oral cavity. We investigated the effects of local cryotherapy on mucositis incidence administrated durng 5-FU treatment. METHODS: In a total of 99 courses, 5-FU and folinic acid combination chemotherapy was given to 40 patients. In our study, we considered every course as a single case, and cryotherapy was given to the same patient in one course but not given in the next. RESULTS: While mucositis developed in 6.7% of the courses given with cryotherapy, this ratio was 38.9% in courses given without cryotherapy. In the logistic regression analysis, development of mucositis had been found to correlate only with cryotherapy. Odds ratio (OR) = 11.5; in the 95% confidence interval (CI) = 3.2 - 41.9; (p = 0.001). DISCUSSION: Results of initial studies evaluating the effects of cryotherapy in preventing mucositis due to 5-FU based chemotherapy regimens were promising. We concluded that oral cooling prevents 5-FU induced mucositis. This effective prophylactic treatment should be used in patients who are at increased risk for developing 5-FU induced mucositis.  相似文献   
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A 16 year old with recurrent meningococcal infections is reported. Absence of haemolytic activity in both the classical and alternative pathways resulted from an absence of functional C8. Addition of functional C8 restored hemolytic activity. Antigenically deficient C8 was present in the serum and isoelectric focusing of serum confirmed the absence of the C8 beta chain. Following the infusion of fresh frozen plasma, we followed the decay in C8 functional activity as well as total haemolytic activity. C8 activity peaked at about 3 h with a half-life survival estimated to be 28 h. The kinetics of total haemolytic activity showed a slower decay with an exponential decline over 72 h and a half-life of 55 h. Fresh frozen plasma may be of value in the treatment of patients with C8 deficiency and acute Neisserial infections.  相似文献   
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Rabbit C3 has been identified in serum by agarose gel electrophoresis and by immunoelectrophoresis, and it was shown that calcium ions slow its mobility. It was purified by methods previously used for human C3. Characteristic conversion products similar to those in other species were produced after various in vitro treatments. Reproducible changes occurred during sub-anaphylactic antigenic challenges in the rabbit which were reflected in total serum complement activity. Anaphylactic death was associated with profound changes in haemolytic complement and C3. These findings provide a basis for further study in the rabbit during experimental immunological disease.  相似文献   
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