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91.
Chiral combined liquid-crystalline polymers (i. e. polymers with the mesogenic groups in the main chain as well as in the side groups) with dipole moments perpendicular to the mesogenic groups were synthesized and characterized. These dipole moments were introduced by lateral substituents, which were located at different parts of the mesogen or directly at the chiral centre. The polymers, thus prepared, show crystalline or glassy phases at room temperature and smectic A, chiral smectic C* or cholesteric phases at higher temperatures. Since the lateral substituents decrease the melting temperature more strongly than the clearing temperature, the liquid-crystalline phases are broadened compared to the unsubstituted polymers. Often glassy liquid-crystalline phases are obtained. The dipole moments perpendicular to the mesogenic groups or at the chiral centre may help to obtain a high spontaneous polarisation in the chiral smectic C* phase (ferroelectricity).  相似文献   
92.
Covalently crosslinked liquid crystalline networks with elastic properties were prepared in isotropic solution from linear liquid crystalline polymers. As linear precursors for the networks were used: (i) polymers with the mesogenic groups in the side groups (polyacrylates and polymethacrylates), (ii) polymers with the mesogenic groups in the main chain (polymalonates) and (iii) polymers with the mesogenic groups in main chain and side groups (“combined liquid crystalline polymers”). In all crosslinked polymers the liquid crystalline phases of the linear polymers are retained. For low degrees of crosslinking (≤2 mol-%) the phase transition temperatures remain nearly unchanged. These elastomers are very soft above Tg and can be easily stretched for more than 100%. For higher degrees of crosslinking the phase transition temperatures are reduced.  相似文献   
93.
Tree pollens are among the most important allergen sources. Allergic cross-reactivity to pollens of trees from various plant orders has so far been classified according to botanical relationships. In this context, cross-reactivities to pollens of trees of the Fagales order (birch, alder, hazel, hornbeam, oak, chestnut), fruits and vegetables, between pollens of the Scrophulariales (olive, ash, plantain, privet, lilac) and pollens of the Coniferales (cedar, cypress, pine) are well established. The application of molecular biology methods for allergen characterization has revealed the molecular nature of many important tree pollen allergens. We review the spectrum of tree pollen allergens and propose a classification of tree pollen and related allergies based on major allergen molecules instead of botanical relationships among the allergenic sources. This molecular classification suggests the major birch pollen allergen, Bet v 1 as a marker for Fagales pollen and related plant food allergies, the major olive pollen allergen, Ole e 1, as a possible marker for Scrophulariales pollen allergy and the cedar allergens, Cry j 1 and Cry j 2, as potential markers for allergy to Coniferales pollens. We exemplify for Fagales pollen allergy and Bet v 1 that major marker allergens are diagnostic tools to determine the disease-eliciting allergen source. Information obtained by diagnostic testing with marker allergens will be important for the appropriate selection of patients for allergen-specific forms of therapy.  相似文献   
94.
Journal of Public Health - The purpose of this paper is to investigate the implementation of value-based care principles in the context of frailty in the perioperative process, highlighting the...  相似文献   
95.
This review evaluates the indications and outcomes of one-anastomosis/mini gastric bypass (OAGB/MGB) reversal to normal anatomy. A systematic literature search and meta-analysis was performed in PubMed, Web of Science, and Scopus for articles published by October 1, 2020, including the keywords “one anastomosis gastric bypass,” “OAGB,” “mini gastric bypass,” “MGB,” “reversal,” “reverse,” “malnutrition,” and “reversal bariatric surgery”. After examining 182 papers involving 11,578 patients, 14 studies were included. A reversal was performed in 119 patients on average 23.6 months after the primary OAGB/MGB surgery. The mean body mass index (BMI) was 22.92 ± 3.47 kg/m2 and the mean albumin level was 25.17 ± 4.21 g/L at reversal. The mean length of the common channel (CC) was 383.57 ± 159.35 cm, with a mean biliopancreatic limb (BPL) length of 214.21 ± 48.45 cm. Pooled estimation of the meta-analysis of prevalence studies reported a prevalence of 1% for reversal. The major signs and symptoms of protein-energy malnutrition were the leading causes of the reversal of OAGB/MGB. Bleeding, leakage, and death due to severe liver failure were the most reported complications after reversal, with an overall incidence of 10.9%. In conclusion, OAGB/MGB reversal has a prevalence of 1% and has a complication rate of 10.9%. Protein-energy malnutrition with hypoalbuminemia was the most common etiology. The mean lengths of BPL and CC were reported as 215 cm and 380 cm, respectively, in the cases. Therefore, special attention should be paid to malnutrition in all OAGB/MGB patients during follow-up to prevent severe malnutrition and subsequent increase in reversal procedures.  相似文献   
96.
97.
Background: The definition of success and failure of a bariatric procedure should include weight loss as well as improvement of comorbidity and quality-of-life (QoL) assessment. QoL measures changes in physical, functional, mental, and social health in order to evaluate benefits of new programs and interventions. Material and Methods: From April 1995 until March 1999, 287 patients underwent laparoscopic adjustable silicone gastric banding (LASGB) at Northwest Hospital Frankfurt a.M. (Germany). In this study, 100 of 287 patients (preoperative mean BMI 48.3 kg/m2; mean age 35.2 years) with a follow-up >18 month were evaluated. All patients underwent anonymous questionnaire (26 questions with a maximum score of 60) about different aspects of QoL outcome after LSAGB. Results: In this study, 4 of 100 patients refused to give an answer to the QoL questions. Therefore 96 patients were evaluated. The QoL auto-evaluation of the patients shows that QoL generally improved after surgery in 92%. Using the scoring system, 44% of patients have excellent, 52% good, and only 4% bad results. The 4 patients who refused had to be classified as failure. General acceptance of LSAGB is wide, but gastrointestinal side effects are recognizable in more than 78% of operated patients. Successful weight loss is followed by an improvement of comorbidities. Conclusions: Safe, effective bariatric procedures increase the quality of life in morbidly obese patients markedly. Bariatric surgeons are committed to support and help their patients until they reach a new quality of life after obesity surgery.  相似文献   
98.
This study investigated Subjective Quality of Life (SQOL) in 42 women with depression, 70 women with alcoholism, and 73 women with schizophrenia within 3 weeks after hospital admission. Twenty-eight of the depressive patients were re-examined after 6 months. SQOL was assessed using the German version of the Lancashire Quality of Life Profile. On average, depressive women expressed dissatisfaction with life as a whole and with 4 out of 8 life domains, and had a lower SQOL than the other two diagnostic groups. Differences remain statistically significant when the influence of age and anxiety/depression is controlled for. SQOL in depressive women improved significantly within the follow up period. Positive SQOL change was moderately correlated with an improvement of depressive symptoms. The results indicate that depressive women after hospital admission express an unusually low SQOL, which seems to have some diagnostic specificity and improves over time. Changes in depressive symptoms do not fully explain SQOL changes.  相似文献   
99.
 · Background: A prospective study was undertaken to determine the transcorneal penetration of three topically applied fluoroquinolones into aqueous humor. · Methods: Cataract patients (n=224) preoperatively received topically applied gyrase inhibitors (0.3% ciprofloxacin, 0.3% norfloxacin, 0.3% ofloxacin) in two different application modes. In application mode I, patients received on the day before operation 3×1 eye drop at 2-h intervals, and on the day of operation 3 drops at 1-h intervals. In application mode II, patients received 9 drops at 15-min intervals on the day of operation only. Just before cataract surgery 50–100 μl aqueous humor was aspirated and stored at –80 °C. The HPLC method was used for measuring the concentration. · Results: The highest concentrations of all tested antibiotics were measured after the mode of application in which one drop was given every 15 min between 06:00 and 08:00 hours before operation. In this mode, ciprofloxacin achieved a mean aqueous level of 379.8±327.8 μg/l (range 33–1388 μg/l), norfloxacin 182.1±118.1 μg/l (range 38–480 μg/l) and ofloxacin 563.9±372.1 μg/l (range 64–1455 μg/l). These mean concentration are all above the MIC90 of gram-negative bacteria like Proteus mirabilis and Escherichia coli. In some cases the concentrations of ciprofloxacin and ofloxacin, but never norfloxacin, reached therapeutic values above the MIC90 of Staphylococcus aureus and Staphylococcus epidermidis · Conclusions: The mean concentration value of 0.3% ciprofloxacin and of 0.3% ofloxacin in the aqueous humor reached the MIC90 values of the frequently occurring gram-positive and gram-negative bacteria. Of the currently available topical fluoroquinolones, ofloxacin achieved the highest aqueous humor concentration. Considering the higher antimicrobial activity of ciprofloxacin, both ciprofloxacin and ofloxacin may be useful ophthalmic agents in antibacterial management, but they are not efficient against Streptococcus pneumoniae and Pseudomonas aeruginosa. Received: 8 September 1997 Revised version received: 19 March 1998 Accepted: 8 April 1998  相似文献   
100.
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