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1.
Some new macroinitiators ( 5 ) containing azo and peroxy groups were synthesized by transformation of esters of poly(ethylene glycol) ( 1 ) (PEG) of different molecular weight with hydroxyl end groups and an azo group in the middle into the corresponding polymers with tert-butylperoxycarbonyl end groups by reaction with terephthaloyl chloride and subsequently with tert-butyl hydroporoxide. Decomposition in the presence of styrene at 60°C or with 3,6,9-triazaun-decane-1,11-diamine in presence of methyl methacrylate gave the corresponding ABA block copolymer 6 and the ABBA block copolymer 7 , respectively. Both block copolymers were used as polymeric initiators. The ABCBA block copolymer 8 was synthesized from 6 and methyl methacrylate or from 7 and styrene by thermally induced polymerization at 80°C. The resulting block copolymers were separated from the homopolymers by selective solvent extraction and characterized by spectroscopic and fractional precipitation methods.  相似文献   
2.
3.
Nineteen patients with Fanconi anemia (FA) and bone marrow failure underwent bone marrow transplantation (BMT) from matched siblings. Median age at BMT was 8.7 years. Conditioning consisted of low-dose cyclophosphamide (CY 5 mg/kg x 4 days) and thoracoabdominal irradiation (TAI 400 cGy). Graft-versus-host disease (GVHD) prophylaxis was cyclosporin A (CsA) in 13 patients and CsA plus methotrexate in 6 patients. Antithymocyte globulin (ATG) was added in the pretransplant as well as the post-transplant period. All patients received high-dose acyclovir from day 2 pre-BMT to day 28 post BMT, and intravenous immunoglobulins (IVIG), 500 mg/kg weekly from day 7 pre-BMT to day 90 post BMT. No fungal prophylaxis was given. All patients engrafted, (median, 14 days for an absolute neutrophil count > or =0.5 x 10(9)/l; median, 37 days for platelet count > or =20 x 10(9)/l). Fourteen (74%) patients are alive with sustained engraftment and are transfusion independent. Three (16.6%) patients developed acute GVHD; none developed chronic GVHD. Five (26%) patients developed invasive fungal infections, and two (10%) developed fatal CMV disease. We believe the addition of ATG may have contributed to the increased incidence of severe life-threatening fungal and viral infections in our series.  相似文献   
4.

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.  相似文献   
5.

Purpose

Obstructive sleep apnea (OSA) is a common disease which is associated with elevated inflammatory markers and adhesion molecules, possibly due to nightly intermittent hypoxia (IH). The purpose of this study was to test the hypothesis that IH would increase systemic inflammatory markers in healthy human males.

Methods

Healthy, young male subjects (n?=?9; 24?±?2?years) were exposed to a single daily isocapnic hypoxia exposure (oxyhemoglobin saturation?=?80%, 1?h/day) for 10 consecutive days. Serum granulocyte macrophage colony-stimulating factor, interferon-??, interleukin-1??, interleukin-6, interleukin-8, leptin, monocyte chemotactic protein-1, vascular endothelial growth factor, intracellular adhesion molecule-1, and vascular cell adhesion molecule-1 were measured before and following the 10?days of IH using Luminex.

Results

Nine subjects completed the study (24?±?2?years; 24?±?2?kg/m2). The mean oxyhemoglobin saturation was 80.8?±?1.6% during the hypoxia exposures. There was no significant change in any of the markers of inflammation (paired t test, P?>?0.2 all cytokines).

Conclusions

These findings suggest that (1) a more substantial or a different pattern of hypoxemia might be necessary to activate systemic inflammation, (2) the system may need to be primed before hypoxic exposure, or (3) increases in inflammatory markers in patients with OSA may be more related to other factors such as obesity or nocturnal arousal.  相似文献   
6.
The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased (p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional and regenerative periodontal surgery.  相似文献   
7.
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative 12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects with bioactive glass compared to the treatment with bioabsorbable membrane.  相似文献   
8.
In all, 22 patients with confirmed Fanconi anemia (FA) underwent stem cell transplantation (SCT) from HLA-matched, related donors at KFSHRC. Median age at SCT was 7.6 years (range, 2.5-14.6 years). Conditioning regimen consisted of cyclophosphamide (CY) 15 mg/kg/day intravenously (i.v.) for 4 consecutive days, in addition to equine antithymocyte globulins (ATG) given i.v. at 40 mg/kg/day for four doses pre-SCT. No radiation therapy was given. For graft-versus-host disease prophylaxis, we used cyclosporin at the standard doses; ATG was added at 20 mg/kg/dose i.v. on days 2, 4, 6, 8, 10, and 12 post-SCT (total of six doses). All patients engrafted and are alive and transfusion independent with a median follow-up time of 20.2 months (range, 3.3-59 months). One patient however developed a decrease in her WBC and platelet count. Her work-up revealed slightly hypocellular bone marrow, and a series of chimerism studies over 1 year confirmed that she has stable mixed chimerism; she remains transfusion independent. We conclude that low-dose CY without radiation therapy can be used satisfactorily in the conditioning of patients with FA undergoing related SCT.  相似文献   
9.
BACKGROUND: Pregnancy complicated by endodermal sinus tumor (EST) of the ovary has rarely been reported. CASE: A huge ovarian EST causing bowel obstruction was found in a 22-year-old patient at 34 weeks of gestation. Abnormally high alpha-fetoprotein (AFP) levels suggested a malignant germ cell tumor of the ovary. The patient was submitted to cesarean section and fertility sparing surgery, and then received four courses of combination chemotherapy. There was no evidence of recurrence 19 months after initial treatment but transvaginal ultrasound (US) evaluation showed an intrauterine pregnancy of six weeks. We delivered a 3,200 g healthy male baby with Apgar scores of 8 and 9 by elective cesarean section at 39 weeks of gestation. CONCLUSIONS: Successful outcome of a second pregnancy is possible after treatment with fertility sparing surgery and combination chemotherapy for an endodermal sinus tumor associated with a first pregnancy. Moreover checking of weekly AFP levels and performing monthly abdominal US could be effective for surveillance of these pregnancies. However management of EST during pregnancy should be based on consideration of the patient's presenting condition, preferences, and gestational age.  相似文献   
10.
Successful medical treatment of cesarean scar pregnancy: a case report   总被引:2,自引:0,他引:2  
OBJECTIVE: Cesarean scar pregnancy is implantation of the pregnancy within the fibrous tissue of the cesarean scar which is completely surrounded by myometrium. METHOD AND RESULT: A 32-year-old woman, gravida 2, para 1 presented at our emergency department with mild lower abdominal pain and minimal vaginal bleeding. She was diagnosed with cesarean scar pregnancy. Conservative treatment with methotrexate 50 mg/m2 was administered IM on days 0 and 8. Her betaHCG value was zero at the 14th week after beginning of the treatment. CONCLUSION: Repeated methotrexate administration in the management of cesarean scar pregnancy should be attempted in informed patients who especially desire fertility and can be closely followed up.  相似文献   
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