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991.
Abstract: Hypercholesterolemia and elevated lipoprotein (a) (Lp[a]) levels are considered to be risk factors for the development and progression of premature atherosclerosis. The purpose of our report is to describe the effects of low density lipoprotein (LDL) apheresis (Liposorber system, Kanegafuchi Chemical Industrial Company LTD, Osaka, Japan) on serum lipoprotein concentrations and the clinical status in 2 male patients with homozygous familial hypercholesterolemia. Compared with pretreatment values, the posttreatment concentrations of total cholesterol, LDL cholesterol, and Lp(a) were significantly reduced by 50–60% (p < 0.0001). The concentration of high density lipoprotein (HDL) cholesterol was slightly affected. After one treatment session, LDL cholesterol and Lp(a) were decreased on average by 65% and then increased to reach about 70–75% of the pretreatment values before the next session. Prior to the treatment with LDL apheresis, each patient had suffered one myocardial infarction and had had 2 coronary angiographies. After treatment with LDL apheresis, neither cardiac complaints nor myocardial infarction were observed. The xanthomas were much decreased during the treatment or disappeared. We conclude that LDL apheresis can be continued safely and without major technical problems for several years. Apheresis effectively lowers the serum levels of total and LDL cholesterol. Furthermore, it reduces Lp(a), which is not influenced by lipid-lowering drugs. The reduction of LDL cholesterol and Lp(a) may delay the progression of the atherosclerotic process, thereby helping to reduce the risk of new episodes of coronary heart disease and thus extending the life expectancy in these patients.  相似文献   
992.
A randomized double-blind, placebo-controlled, trial of 5,6 benzo-[alpha]-pyrone (coumarin, '56 BaP') and of diethylcarbamazine (DEC) is being performed on patients with filaritic lymphoedema and elephantiasis over two years, using matched groups. In 169 patients there were significant (1% level) reductions in the amounts of oedema for the patients taking 56 BaP. The excess limb volumes were reduced from 40 to 25% over two years. A similar, but less significant (5% level), improvement was found for the circumference measurements. The rate of reduction was increased when the initial amount of oedema was greater. This therapy, while much slower than many other methods of treatment, does convert a slowly worsening condition into a slowly improving one. There were no significant reductions in the amount of oedema following DEC treatment.  相似文献   
993.
Carbonic anhydrase (CA) II, CA IX, and CA XII are expressed in various neoplasias and have been linked to tumorigenesis. We examined their expression in three different groups of colorectal cancer [i.e., microsatellite stable (MSS), microsatellite instable (MSI), and hereditary nonpolyposis colorectal cancer (HNPCC)]. First, we analyzed gene expression profiles of 113 specimens by a microarray method to study the expression of various CA isozymes in the subgroups of colorectal cancer. The results indicated that mRNAs for CA II and CA XII are down-regulated and CA IX mRNA is up-regulated in all three tumor categories when compared with the normal tissue. The up-regulation of CA IX was greatest in the HNPCC group. For more information, 77 specimens were immunohistochemically stained to study the levels of CA II, CA IX, and CA XII. Immunohistochemical analyses further confirmed that the subgroups express CA II, CA IX, and CA XII differentially, and the HNPCC tumors express high levels of CA IX. Expression of these CAs did not correlate to Dukes stage or grade of differentiation. Our results show that CAs are differentially expressed in the subgroups of colorectal cancer, and CA IX expression seems to be very high in most cases of HNPCC. CA IX could be a potential diagnostic and therapeutic target in HNPCC.  相似文献   
994.
The geometries, tautomerization energies, and dipole moments of the tautomeric species of the 2-amino-2-oxazoline heterocycle were calculated with full geometry optimization using semiempirical (MNDO, AM1 and PM3) and ab initio (RHF/6–31G) methods. The planar conformation of the amino form is well reproduced by the semiempirical and by the ab initio methods as compared with X-ray structures in which this form is found. However the exocyclic nitrogen atom is pyramidalized in the semiempirical geometries whereas the ab initio method reproduces a sp2 hybridization state. The twisted conformation of the imino form is better reproduced by the ab initio calculation. All methods (semiempirical and ab initio) show a stability energy value in favour of the amino tautomer of the neutral heterocycle. On the contrary, the dominant species of the charged heterocycle is the imino tautomer, protonated on the exocyclic nitrogen atom. Molecular electrostatic potential calculations confirmed this tendency. Finally the 3D-lipophilicity profile of the heterocycle completed the investigation of the tautomerism.  相似文献   
995.
OBJECTIVES: The contact of cardiopulmonary bypass surface and patient's blood activates systemic inflammatory response which aggravates ischemia-reperfusion injury. This study evaluates the effects of cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) on cerebral protection using different steroid administration protocols. METHODS: Eighteen (n=6/group) 4 week-old piglets were divided in three groups. Methylprednisolone (30 mg/kg) was administered intravenously 4 h prior to CPB in Group I, or added in pump prime in group II. Group III received no steroid. All animals were cooled to 15 degrees C followed by 100 min of DHCA, then rewarmed over 40 min and sacrificed 6 h after CPB. Post-operative weight gain, bioelectrical impedance, colloid oncotic pressure (COP) and interleukin-6 (IL-6) were evaluated. Determination of cerebral trypan blue and immunohistochemical assays of transforming growth factor (TGF)-beta1 and caspase-3 activities were performed. RESULTS: Post-operative % weight gain (13.0+/-3.8 (I) versus 26.4+/-9.9 (II) versus 22.6+/-6.4 (III), P=0.02); % bioimpedance reduction (14.5+/-8.0 (I) versus 38.3+/-13.3 (II) versus 30.5+/-8.0 (III), P=0.003); mean COP (mmHg) (14.9+/-1.8 (I) versus 10.9+/-2.0 (II) versus 6.5+/-1.8 (III), P=0.0001) and systemic IL-6 levels (pg/ml) (208.2+/-353.0 (I) versus 1562.1+/-1111.4 (II) versus 1712.3+/-533.2 (III), P=0.01) were significantly different between the groups. Spectrophotometric analysis of cerebral trypan blue (ng/g dry weight) was significantly different between the groups (0.0053+/-0.0010 (I) versus 0.0096+/-0.0026 (II) versus 0.0090+/-0.0019 (III), P=0.004). TGF-beta1 scores were 3.3+/-0.8 (I) versus 1.5+/-0.8 (II) versus 1.5+/-0.5 (III), P<0.05, groups I versus II and I versus III. Remarkable perivascular caspase-3 activity was observed in groups II and III. CONCLUSION: Different timing of steroid administration results in different inflammatory mediator response. Steroid in CPB prime is not significantly better than no steroid treatment, while systemic steroid pre-treatment significantly decreases systemic manifestation of inflammatory response and brain damage.  相似文献   
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999.
A tumor model using human squamous cell carcinoma of the cervix implanted in nude mice was developed. Hydroxyurea and Adriamycin were used as radiopotentiators. A regression delay was observed in tumors treated with radiation therapy alone and radiation therapy and Hydroxyurea. No regression delay was observed when the tumors were treated with radiation therapy and Adriamycin. Six weeks after treatment, 75% of the tumors treated with radiation therapy and Adriamycin were not palpable, while all the tumors were present in the group treated with radiation therapy alone and radiation therapy and Hydroxyurea. No difference in tumor response was noted between the group receiving radiation therapy alone and radiation therapy and Hydroxyurea. This preliminary observation shows obvious interaction between Adriamycin and radiation therapy, suggesting radiopotentiating activity. The tumor model was found useful and practical.  相似文献   
1000.
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