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1.

Background  

For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast.  相似文献   
2.
INTRODUCTION: The aim of this study was to review complications in a series of 1264 consecutive patients who were operated in a single centre during a 20-year-period. MATERIAL AND METHODS: Complications were documented, their incidences calculated and compared with data from the literature. RESULTS: In 35 patients (2.8%) infection developed requiring extraoral incision and drainage; in 27 patients (2.1%) the inferior alveolar nerve was inadvertently cut; 18 patients (1.4%) had to undergo re-operation due to bending or fracture of osteosynthesis material; 15 patients (1.2%) suffered from bleeding complications; in 12 patients (0.9%) an unfavourable split occurred. In 8 patients (0.6%) foreign bodies were left in situ; in 7 patients a partial weakness of the facial nerve occurred, which was permanent in 1 patient. Six patients (0.5%) with a significantly higher age than average (mean: 33.6 years in comparison with 23.1 years) developed non-union at the site of osteotomy, and the mandible had to be bone grafted. Two patients (0.2%) developed osteomyelitis, and in one patient airway problems led to a need for tracheostomy (0.1%). CONCLUSION: Although some of these complications of bilateral sagittal split with osteotomy carry severe limitations in health related quality of life, it remains an overall safe procedure, demanding, however, comprehensive informed consent. Good knowledge of technical reasons for these complications should help to reduce their incidence.  相似文献   
3.

Background  

Factors of IT adoption have largely been discussed in the literature. However, existing frameworks (such as TAM or TTF) are failing to include one important aspect, the interaction between user and task.  相似文献   
4.
Synthetic glucocorticoids are administered to pregnant women in premature labour to accelerate fetal lung maturation at a time when fetal cerebrovascular and endocrine systems are maturing. Exposure to glucocorticoids at 0.8–0.9 of gestation increases peripheral and cerebrovascular resistance (CVR) in fetal sheep. We examined whether the increase of CVR and its adverse effect on cerebral blood flow (CBF) depend on the current level of maturation of the pituitary–adrenal axis and the cerebrovascular system. Using fluorescent microspheres, regional CBF was measured in 11 brain regions before and 24 h and 48 h after the start of 3.3 μg kg−1 h−1 betamethasone ( n = 8) or vehicle ( n = 7) infusions to fetal sheep at 0.73 of gestation. Hypercapnic challenges were performed before and 24 h after the onset of betamethasone exposure to examine betamethasone effects on cerebrovascular reactivity. Betamethasone exposure decreased CBF by approximately 40% in all brain regions after 24 h of infusion ( P < 0.05). The decline in CBF was mediated by a CVR increase of 111 ± 16% in the cerebral cortex and 129 ± 29% in subcortical regions ( P < 0.05). Hypercapnic cerebral vasodilatation and associated increase in CBF were blunted ( P < 0.05). Fetal CBF recovered after 48 h of betamethasone administration. There were no differences in glucocorticoid induced CBF and CVR changes compared with our previous findings at 0.87 of gestation. We conclude that the cerebrovascular effects of antenatal glucocorticoids are independent of cerebrovascular maturation and preparturient increase in activity of the fetal pituitary–adrenal axis.  相似文献   
5.
6.
The goal of this study was to evaluate the performance of a computer-aided detection (CAD) system in full-field digital mammography (Senographe 2000D, General Electric, Buc, France) in finding out carcinomas depending on the parenchymal density. A total of 226 mediolateral oblique (MLO) and 186 craniocaudal (CC) mammographic views of histologically proven cancers were retrospectively evaluated with a digital CAD system (ImageChecker V2.3 R2 Technology, Los Altos, CA, USA). Malignant tumors were detected correctly by CAD in MLO view in 84.85% in breasts with parenchymal tissue density of the American College of Radiology (ACR) type 1, in 70.33% of the ACR type 2, in 68.12% of the ACR type 3, and in 69.70% of the ACR type 4. For the CC view, similar results were found according to the ACR types. Using the chi-square and McNemar tests, there was no statistical significance. However, a trend of better detection could be seen with decreasing ACR type. In conclusion, there seems to be a tendency for breast tissue density to affect the detection rate of breast cancer when using the CAD system.  相似文献   
7.
Four different tests for detection of rubella-specific IgM antibodies were compared: two Ig separation methods (centrifugation and chromatography) with subsequent haemagglutination inhibition test and two commercially available ELISA tests. The 114 sera tested had been sent to the diagnostic laboratory, mostly with insufficient clinical histories. Agreement between the centrifugation method and one of the ELISA tests was good (2 divergent results with 107 sera tested), while the other ELISA test yielded more positive (partly perhaps non-specific) results. The chromatographic method did not separate the Ig classes as reliably as the centrifugation method, but because of its simplicity it may be useful, if adequate test controls are performed. The divergent results are discussed. It is postulated that in cases with pending induced abortion, two independent tests should be performed.  相似文献   
8.
Antibodies against bacterial capsular polysaccharides play a critical protective role. Responses to these antigens can occur without the help or control of T cells and are associated with marginal zone (MZ) B cells. Capsular antigens are diverse and some cross-react with self-carbohydrate epitopes. This diversity may explain the recruitment of non-autoreactive recirculating B cells and memory B cells to the MZ in addition to other B cells, some of which are weakly autoreactive cells, that are recruited to the MZ without entering the recirculating pool. To test whether memory B cells respond to polysaccharide-based antigens, mice with hapten-specific memory B cells were challenged with hapten-polysaccharide. Hapten-specific plasma cells producing high affinity antibody with Ig V-region mutations were induced. To test whether naive recirculating B cells can form MZ cells that respond to polysaccharide, recirculating B cells from lymph nodes were transferred into Rag-1-deficient mice. MZ cells differentiated from the donor cells without proliferation or T cell help and responded to polysaccharide-based antigen. The differentiation of B cells both from germinal centers and the recirculating pool to the MZ phenotype is likely to make an important contribution to the repertoire of B cells that respond to polysaccharide antigens.  相似文献   
9.
In the first experiment, the effects of lesions of (1) the amygdala, (2) its major efferent projection system, the stria terminalis or (3) other non-limbic brain sites on the induction of maternal behavior in the nulliparous female rat were investigated. Animals sustaining lesions of either the amygdala or the stria terminalis became maternal more rapidly than did control animals. In the second study the effects of lesions to different portions of the amygdala on both maternal and fear responding were investigated. It was found that animals sustaining damage to the corticomedial amygdaloid nuclei became maternal more quickly than did animals sustaining either basolateral amygdaloid damage or no amygdaloid damage. Also in comparison to lesioned controls, animals with lesions of the amygdala showed reduced ‘fearfulness’ on a number of fear-mediated tasks. The third study attempted to interrelate fear responsiveness and maternal behavior by observing nulliparous animals with amygdaloid or stria terminalis lesions for their responses to unfamiliar foster pups placed daily into their preferred nesting quadrant. While control animals actively avoided pups placed into their nest sites (by moving their nest site to another quadrant of the cage), animals with amygdaloid lesions or lesions of the stria terminalis, did not. These results are interpreted to mean that nulliparous females generally do not respond maternally to pups because these females are, in general, more neophobic than parturient females and they tend to find pups and their novel odors, aversive. This aspect of their behavior is likely mediated by the amygdala. These data are discussed in terms of their relevance to the rapid maternal responsiveness normally shown by the female at parturition.  相似文献   
10.
Background: Vitamin D plays a pivotal role in calcium and phosphorus metabolism, also influencing bone tissue. Several studies have reported that vitamin D blood levels were significantly lower in people with obesity, probably due to its uptake by the adipose tissue. Clinical studies that investigated the changes of circulating levels of vitamin D following weight loss reported controversial data. A very low-calorie ketogenic diet is acknowledged as a reliable treatment to achieve a rapid weight loss. Therefore, we investigated the effect of weight loss, consequent to a very low-calorie ketogenic diet, on vitamin D blood concentrations. Methods: A cohort of 31 people with obesity underwent a very low-calorie ketogenic diet for 10–12 weeks. The serum concentrations of vitamin D, parathormone, calcium and phosphorous were measured before and after weight loss; they were compared to a control group of 20 non-obese, non-diabetic, age- and gender-matched persons. Results: Patients with obesity had a higher habitual intake of vitamin D than the control group (p < 0.05). However, the vitamin D blood levels of the obese group were significantly lower than those of the control group (p < 0.005) and they increased after weight loss (p < 0.001). At baseline, vitamin D blood concentrations of the persons with obesity were significantly correlated with both fat mass–kg (r = −0.40; p < 0.05) and body mass index (r = −0.47; p < 0.01). Following very low-calorie ketogenic diet, the change in vitamin D serum concentrations was correlated only with the change in fat mass–kg (r = −0.43; p < 0.01). Conclusion: This study confirmed that patients with obesity have lower vitamin D levels that normalize after significant weight loss, supporting the hypothesis that vitamin D is stored in the adipose tissue and released following weight loss.  相似文献   
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