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71.
Wolf–Hirschhorn syndrome is a rare genetic disease caused by a chromosomal deletion of the distal short arm of Chromosome 4. It is associated with multisystem abnormalities, including delayed growth, characteristic facial features, epilepsy, and skeletal abnormalities. We report three patients who developed hip displacement, and describe the occurrence of delayed and nonunion in patients who underwent corrective proximal femoral osteotomy for hip displacement. We also performed a literature review identifying common musculoskeletal presentations associated with the condition. Patients with Wolf–Hirschhorn Syndrome are at risk of hip displacement (subluxation), and we would advocate annual hip surveillance in this patient group.  相似文献   
72.
The growing energy demand speed up the designing of competent photovoltaic materials. Herein, five zinc phthalocyanine-based donor materials T1–T5 are designed by substituting various groups (isopropoxy, cyano, fluoro, methoxycarbonyl, and dicyanomethyl) around zinc phthalocyanine. B3LYP/6-31G (d,p) level density functional theory (DFT) was used to investigate the optoelectronic properties of five zinc phthalocyanine-based dyes T1–T5 for dye-sensitized solar cells. The designed molecule T1 shows maximum absorption wavelength (λmax) in the absorption spectrum at 708.89 and 751.88 nm both in gaseous state and in THF (tetrahydrofuran) solvent. The Eg value of T1 (1.86 eV) is less than reference R, indicating a greater charge transfer rate for T1 among the molecules. The values of open-circuit voltages achieved with acceptor polymer PC71BM are higher than R except for T1 and are 0.69 V, 1.95 V, 1.20 V, 1.44 V, and 1.84 V for T1, T2, T3, T4, and T5, respectively. The lower the reorganization energy, the higher the charge transfer for T1 due to its lower hole mobility (0.06297 eV) than R. Thus, the designed T1–T5 molecules are expected to exhibit superior performance in dye-sensitized solar cells.

We used a quantum chemical approach to investigate the optoelectronic properties of dyes T1–T5 for dye-sensitized solar cells using DFT and TD-DFT computation. The newly designed molecules exhibited outstanding photovoltaic and optoelectronic properties.  相似文献   
73.
BACKGROUND: Wear of the underside of modular tibial inserts (backside wear) in total knee replacements has been reported by several authors. Although, for some implant designs, this phenomenon seems to contribute to osteolysis, the actual volume of material lost through wear of the backside surface has not been quantified. This study describes the results of computerized measurements of tibial inserts of one design known to be associated with a high prevalence of backside wear in situ. METHODS: A series of retrieved total knee components of one design were examined. The duration of implantation of the retrieved components ranged from thirty-six to 146 months. Laser surface profilometry and computer-aided design software were used to develop individual three-dimensional models of each worn, retrieved tibial insert to compare with scanned unused inserts. Volumetric subtraction of both models revealed the material lost because of backside wear. RESULTS: Worn and unworn areas on the backside surface were easily identified by stereomicroscopy and laser profilometry. The computer reconstructions showed that, in all retrievals, all unworn surfaces on the nonarticulating surface lay in one plane. The average volume (and standard deviation) of the material lost because of backside wear was 925 +/- 637 mm(3) (range, 197 to 2720 mm(3)). On the basis of the time in situ for each implant, the average volumetric wear rate was 138 +/- 95 mm(3)/yr. CONCLUSIONS: The predicted volume of material removed because of backside wear is substantial and may be sufficient to induce osteolysis. Our results suggest that peg-like protrusions are not generated by the extrusion of polyethylene into screw-holes within the base-plate but by abrasion of the underside of the bearing insert, leaving the protruding pegs as the only remnants of the original surface.  相似文献   
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Sea buckthorn (Hippophae rhamnoides ssp. turkestanica) is a very important medicinal plant in northern areas of Pakistan. The fruit of sea buckthorn is rich in nutrients and medicinal compounds such as vitamins, carotene, flavonoids, essential oil, carbohydrates, organic acids, amino acids, and minerals. In order to compare various populations of sea buckthorn for chemical composition, eight populations from different areas of northern Pakistan were compared using fruit characteristics. Phytochemical analysis of berries showed vitamin C (250-333 mg/100 g), seed oil (7.69-13.7%), oil in softer pulp (19.2-29.1%), phytosterol content of seed oil (3.3-5.5%), and anthocyanin (0.5-25 mg/L), while the mineral element composition analysis revealed high contents of potassium (140-360 ppm), sodium (20-80 ppm), calcium (70-98 ppm), magnesium (150-240 ppm), iron (40-150 ppm), and phosphorus (110-133 ppm). This study established sea buckthorn berries as a good source of biochemical and mineral elements. The high variation between different populations shows the potential of selecting and breeding of the raw material for various defined purposes.  相似文献   
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β-Seleno amines were screened for in vitro antioxidant activity. The compounds (C1-C4) were tested against lipid peroxidation induced by iron and sodium nitroprusside in rat brain and liver homogenates. The compounds showed inhibition against thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants (10μM FeSO(4) and 5μM sodium nitroprusside (SNP) in rat brain and liver homogenates. The compounds exhibited strong antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and phosphomolybdenum assays. The IC(50) values revealed that the β-seleno amines in which the amino group was protected with protecting groups tert-butyloxycarbonyl (Boc) and Tosyl (Ts) groups showed better antioxidant profiles compared to the free monoselenides. The total antioxidant activity of C1, C2, C3 and C4 were found to be 85.2±11.5, 114±7.9, 138±8.5, 125.81±5.2μM/ml of ascorbic acid respectively. Therefore, these compounds may be used as synthetic antioxidants.  相似文献   
79.
ABSTRACT: BACKGROUND: The aim of the study was to evaluate potential chemotherapy-induced microsatellite instability, loss of heterozygosity, loss of expression in mismatch repair proteins and associations with clinical findings in breast cancer patients, especially resistance to chemotherapy and/or development of other tumors in the four years following chemotherapy treatment. METHODS: A comprehensive study of chemotherapy-related effects with a follow-up period of 48 months post treatment was conducted. A total of 369 peripheral blood samples were collected from 123 de novo breast cancer patients. Microsatellite instability and loss of heterozygosity in five commonly used marker loci (including Tp53-Alu of the tumor suppressor gene TP53) were analyzed in blood samples. Sampling was conducted on three occasions; 4--5 weeks prior to the first chemotherapy session (pre-treatment), to serve as a baseline, followed by two consecutive draws at 12 weeks intervals from the first collection. Mismatch repair protein expression was evaluated in cancer tissues using immunohistochemistry for three mismatch-repair related proteins. RESULTS: A total of 70.7% of the patients showed microsatellite instability for at least one locus, including 18.6% marked as high-positive and 52.1% as low-positive; 35.8% showed loss of heterozygosity in addition to microsatellite instability, while 29.3% exhibited microsatellite stability. The following incidence rates for microsatellite instability and loss of heterozygosity were detected: 39.08% positive for Tp53-Alu, 31.1% for locus Mfd41, and 25.3% for locus Mfd28. A higher occurrence of loss of heterozygosity was noted with alleles 399 and 404 of Tp53-Alu. The mismatch repair protein expression analysis showed that the chemotherapy caused a loss of 29.3% in hMLH1 expression, and 18.7% and 25.2% loss in hMSH2 and P53 expression, respectively. A strong correlation between low or deficient hMSH2 protein expression and occurrence of mismatch repair/loss of heterozygosity events in Mfd41, Tp53-Alu, and Mfd28 was evident. A significant association between mismatch repair/loss of heterozygosity and incidence of secondary tumors was also established CONCLUSION: Our results suggest that microsatellite instability, loss of heterozygosity, and deficiency in mismatch repair may serve as early prognostic factors for potential chemotherapy-related side effects in breast cancer patients.  相似文献   
80.
Synthetic bovine Lys-gamma 3MSH was found to potentiate the steroidogenic action of ACTH during incubation of rat adrenal fasciculata-reticularis cells in vitro. On the other hand, Lys-gamma 3MSH did not increase basal levels of or ACTH-induced (submaximal) increases in cellular concentrations of cAMP or phosphatidylinositol. Thus, Lys-gamma 3MSH does not appear to simply increase the overall action of ACTH, and moreover, it appears to potentiate steroidogenesis by a mechanism that is considerably different from that employed by ACTH. Observance of an effect of ACTH and failure to observe an effect of gamma 3MSH on adrenal phosphatidylinositol are in keeping with our previous postulation that phospholipids in the phosphatidate-inositide cycle play an important role in promoting cholesterol side-chain cleavage, since ACTH, but not gamma 3MSH, reportedly increases cholesterol side-chain cleavage. In addition, we also presently observed that Lys-gamma 3MSH can markedly increase corticosterone production in the face of a fixed, relatively small, submaximal, ACTH-induced increase in phosphatidylinositol. Thus, if gamma 3MSH enhances steroidogenesis by increasing free cholesterol availability, the latter may require another factor to initiate steroidogenesis, but is, nevertheless, an important determinant of the rate of steroidogenesis.  相似文献   
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