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排序方式: 共有618条查询结果,搜索用时 62 毫秒
1.
Ophira Salomon Joseph Moisseiev Tamara Vilganski Rima Dardik Shimon Kurtz Eva Shpringer David M Steinberg Nurit Rosenberg 《Blood coagulation & fibrinolysis》2006,17(6):485-488
To determine whether polymorphisms of platelet surface glycoprotein associated with arterial thrombosis are risk factors for branch retinal vein occlusion. A case-control study in which 69 patients with branch retinal vein occlusion and 147 controls who attended the eye clinic for nonvascular complications participated. DNA was extracted from whole blood and analyzed for genotyping of platelet glycoprotein polymorphisms by polymerase chain reactions and specific restricted enzymes. No relationship was found between the four platelet glycoprotein polymorphisms i.e. GPIa C807T, VNTR and Kozak of glycoprotein Ibalpha, the HPA-1 of glycoprotein IIIa and the occurrence of branch retinal vein occlusion. The HPA-2 polymorphism was found in 18 out 60 (30%) patients with branch retinal vein occlusion in comparison with 27 out 142 (19%) of controls, with an estimated odds ratio of 1.8 (95% confidence interval, 0.91-3.65). The four platelet glycoprotein polymorphisms are not risk factors for branch retinal vein occlusion and therefore it seems unnecessary to screen those patients for it. A larger study is required, however, to determine whether HPA-2 is a novel risk factor for branch retinal vein occlusion. 相似文献
2.
Ullmann Yehuda MD Shoshani Oren MD Fodor Adriana MD Ramon Yitzhak MD Carmi Nurit PhD Eldor Liron MD Gilhar Amos MD 《Dermatologic surgery》2005,31(10):1304-1307
BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient. 相似文献
3.
OBJECTIVE: To evaluate the effect of radiant warmers on skin barrier function in preterm infants. METHODOLOGY: Transepidermal water loss (TEWL) and stratum corneum hydration were measured in 30 preterm infants (birth weight 825 to 2220 g) in seven body areas: forehead, upper back, cubital fossa, palms, soles, abdomen, and inguinal region. Measurements were performed under radiant warmer and incubator conditions. Each patient served as his/her control. RESULTS: TEWL was significantly higher in the radiant warmer compared to the incubator condition in only two areas: forehead and back. The overall mean difference in percentage TEWL between the conditions was 15%. Stratum corneum hydration was not affected by the radiant warmer. CONCLUSIONS: The use of radiant warmers does not significantly decrease barrier function in the preterm infant. 相似文献
4.
Eldar-Geva T Margalioth EJ Gal M Ben-Chetrit A Algur N Zylber-Haran E Brooks B Huerta M Spitz IM 《Human reproduction (Oxford, England)》2005,20(7):1814-1819
BACKGROUND: Anti-Mullerian hormone (AMH) is expressed in pre- and small-antral follicles. High serum levels are found in women with polycystic ovaries (PCO), accordant with their increased content of small follicles. To evaluate the relationship between AMH, folliculogenesis and hyperandrogenism, we compared serum AMH levels between women with PCO with and without hyperandrogenism and normal controls during controlled ovarian hyperstimulation (COH). METHODS: Nineteen women with PCO and hyperandrogenism (group A), 10 women with PCO but no hyperandrogenism (group B) and 23 ovulatory women with normal ovarian morphology (group C, controls) underwent COH with the long protocol. Serum levels of AMH, estradiol, androstenedione and follicular tracking were determined before gonadotropins treatment (day 0) and every 2-4 days up to the day of HCG administration. RESULTS: AMH levels declined gradually throughout COH in the three groups, but remained higher in groups A and B compared with the controls. Significantly higher levels were found in group A compared with group B, despite comparable numbers of small follicles. Multiple regression analysis revealed that both the number of small follicles and serum androgens were correlated to AMH. CONCLUSIONS: Women with PCO have higher serum AMH levels during COH than controls. Hyperandrogenism is associated with an additional increase in AMH. It is conceivable that hyperandrogenism may reflect more severe disruption of folliculogenesis in women with PCO or may affect AMH secretion. 相似文献
5.
The bactericidal and bacteriolytic effects of lysolecithin (LL) and egg-white lysozyme (LYZ) on Staph. aureus and group A streptococci and the solubilization of phospholipids from the bacterial membranes by these agents was studied. Low concentrations of lysolecithin (1--10 microgrames/ml) are highly bactericidal for Steph. aureus and group A streptococci, but induce neither bacteriolysis nor solubilization of a substantial amount of membrane phospholipids. On the other hand, while LL at greater than 50 micrograms/ml causes substantial lipid release, a combination of LL and LYZ is absolutely needed to solubilize lipids from streptococci. This combination is, however, not bacteriolytic for this microrganism. The solubilization of lipids from staphylococci by LL is much faster than that induced in streptococci by LL + LYZ. The solubilization of the bulk of membrane lipids from staphylococci can also be achieved by Triton X-100 and by sodium lauryl sulfate and from group A streptococci by Triton X-100 plus LYZ. A variety of other detergents (e.g., Cetavlon, sodium taurocholate, cetyl pyrdinium chloride) have no lipid-releasing properties even in the presence of LYZ. The release of lipids by LYZ (in the presence of LL) from group A streptococci is related to its enzymatic activity, on a still unknown substrate, but not to its cationic nature as this muramidase cannot be replaced by a variety of cation substances (histone, polylysin, leukocyte cationic proteins, polymyxin B, and spermidine). The release of lipids from staphylococci by LL is not inhibited by a variety of anionic and cationic polyelectrocytes (heparin, liquoid, chondroitin sulfate, DNA histone, and polylysine) which markedly inhibit the release of lipids from group A streptococci by LL and LYZ. Streptococci that had been cultivated in the presence of subinhibitory concentrations of penicillin G lose their membrane phospholipids to a larger extent and by much smaller concentrations of LL and LYZ, as compared to controls, suggesting that the interference with the synthesis of the peptidoglycan increases the accessibility of the cell membrane to the lipid-releasing agents. The mechanism by which LL collaborates with LYZ in lipid release is still not known. The possible role of bacterial lipids and lyso compounds in the control of bacterial survival in inflammatory sites is briefly discussed. 相似文献
6.
7.
Abo-Ali Ehab A. Al-Ghanmi Amal Hadad Hajar Etaiwi Jumanah Bhutta Kainat Hadad Najlaa Almilaibary Abdullah Ghareeb Wesssam A. Sanad Ashraf Zaytoun Sameh 《The journal of primary prevention》2022,43(5):659-671
Journal of Prevention - Excessive smartphone use leads to several physical and psychological disorders, particularly among young adults. This study aimed to investigate the prevalence and the... 相似文献
8.
Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether
severely obese subjects (BMI 40-50 kg m−2) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition.
Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls.
Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances
(RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly
ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively.
The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2,
16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all
subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake
(20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The
intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did
not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated
with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests
the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status. 相似文献
9.
Bialer Meir Hadad Salim Kadry Bashier Abdul-Hai Ali Haj-Yehia Abdulla Sterling Jeff Herzig Yaacov Yagen Boris 《Pharmaceutical research》1996,13(2):284-289
Purpose. The described structure pharmacokinetic pharmacodynamic relationships (SPPR) study explored the utilization of tetramethylcyclopropane analogues of valpromide (VPD), or tetra-methylcyclopropane carboxamide derivatives of valproic acid (VPA) as new antiepileptics.
Methods. The study was carried out by investigating the pharmacokinetics in dogs and pharmacodynamics (anticonvulsant activity and neurotoxicity) of the following three cyclopropane analogues of VPD: 2,2,3,3-tetramethylcyclopropane carboxamide (TMCD), N-methyl TMCD (M-TMCD) and N-[(2,2,3,3-tetramethylcyclopropyl)carbonyl]-glycinamide (TMC-GLD).
Results. The three investigated compounds showed a good anticonvulsant profile in mice and rats due to the fact that they were metabolically stable VPD analogues which were not biotransformed to their non-active acid, 2,2,3,3-tetramethylcyclopropane carboxylic acid (TMCA). M-TMCD was metabolized to TMCD and TMC-GLD underwent partial biotransformation to its glycine analogue N-[(2,2,3,3-tetramethylcyclopropyl)carbonyl]-glycine (TMC-GLN). Unlike TMC-GLN, the above mentioned amides had low clearance and a relatively long half life.
Conclusions. In contrast to VPD which is biotransformed to VPA, the aforementioned cyclopropane derivatives were found to be stable to amide-acid biotransformation. TMCD and M-TMCD show that cyclic analogues of VPD, like its aliphatic isomers, must have either two substitutions at the position to the carbonyl, such as in the case of TMCD, or a substitution in the and in the positions like in the VPD isomer, valnoctamide (VCD). This paper discusses the antiepileptic potential of tetramethylcyclopropane analogues of VPD which are in animal models more potent than VPA and may be non-teratogenic and non-hepatotoxic. 相似文献
10.
The product of gene P of coliphage λ 总被引:1,自引:0,他引:1
The product of gene P of phage λ was identified. The P protein has an apparent molecular weight of 23,000 as estimated by sodium dodecyl sulfate-polyacrylamide-gel electrophoresis. The phage λimmP22c2ts 30 which carries gene 12 of phage P22 in place of the λ P gene, is unable to synthesize the 23,000-molecular weight protein band. This phage synthesizes a protein of molecular weight 50,000. 相似文献