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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.

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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
8.
Given the effects of environmental pollution and different biotic factors on some important biochemical markers, as enzymes, two fish species inhabiting the Sariyar Dam Lake, Turkey have been investigated. Ethoxyresorufin O-deethylase, glutathion S-transferase, lactate dehydrogenase, alkaline phosphatase, acid phosphatase, and alanine and aspartate amino transferase activities have been measured in liver samples of Cyprinus carpio and Capoeta tinca. Also, brain acetylcholinesterase and carboxylesterase activities have been measured for the same samples. Selected enzymes confirmed that Sariyar basin is polluted by urban wastes and agricultural and industrial activities for many years. Organochlorine (OC) pesticide residues, caused by intensive agricultural activities, have also been observed in water, sediment samples, and adipose tissues of carp. Monitored results showed that SDL was polluted by different kinds of OC compounds such as DDT and its derivatives which are accumulated in adipose tissues of carp. Highest accumulation was found for beta-BHC in carp. The changes of enzyme activities in this study may be related to environmental pollution, while enzyme activity variations could be attributed to variable pollutants and variable concentrations of these pollutants. The results highlighted the potential convenience of these biomarkers to be used as components of environmental monitoring program in risk assessment studies in SDL. Since a seasonal variation in selected enzyme activities was found, the possible implications of such variability in the use of these enzymes as environmental biomarkers are also discussed. Hepatic cytosolic EROD did not show any significance according to the pollution factors in the lake which may be attributed to relatively less contamination by organic compounds such as PAH products.  相似文献   
9.
10.
BACKGROUND: To determine if the distribution of prognostic factors accounted for the differences when the outcome for localised Ewing Sarcoma/PNET bone in Saudi Arabia was compared with results from countries with well developed health care systems. PROCEDURE: Retrospective analysis was undertaken of 163 consecutive patients of all ages, treated with radical intent at KFSHRC from 1975 to 1998. Standard chemotherapy was commenced in all patients. The local treatment modality was resection +/- radiation in 30% and radiation treatment alone in 67%. Size data were available for 51 patients treated from 1994 to 1998, inclusive. One third of these patients had tumors with volume >500 ml. RESULTS: Three year survival significantly increased with the year of diagnosis, 1975-1988 45%; 1989-1993 55%; and 1993-1998 63% (P = 0.006). Favorable prognostic factors were age < or =14 (P = 0.07); site, distal extremity, and skull (P = 0.08); and volume < or = 200 ml (P = 0.06). Secondary prognostic factors were response to induction chemotherapy, both histological, 100% necrosis, (P = 0.04) and clinical CR+PR, (P = 0.02). From 1994 to 1998, 3 year survival for tumors in the distal extremity and skull was 80% and for small tumors, < 200 ml, at any site was 82%. In comparison, the 3 year survival for patients with tumors at any other sites was 60%, and for tumors >200 ml, 55%. CONCLUSIONS: Overall survival progressively improved. From 1994 to 1998 the survival of patients with small tumors and/or favorable sites was similar to the best reported results. It was not possible to compare results by tumor size for large tumors, > 500 ml, due to the absence of data from elsewhere. A better staging system is required for the international comparison of results.  相似文献   
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