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1.
Quisqualic acid NBM lesions had no effect on water maze performance, but slightly impaired passive avoidance acquisition. GammavinylGABA treatment alone had no effect on the passive avoidance and water maze performance, but aggravated acquisition deficit in rats subjected to NBM lesioning. However, gammavinylGABA-treated NBM-lesioned rats reached control level of performance.  相似文献   
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The aim of the study was clinical and X-ray evaluation of two patients treated because of fractures of shaft of femur with coexisting hip joint osteoarthritis with cemented THR. Both patients were treated just after the injury. Reduction of fractures were made to both patients. Stabilization of fracture in one patient was made with metal plate and cables, stabilization with only cables was made to second patient. Exeter THR with standard stem was implanted to first patient, and with long stem to the second one. Both patients have good clinical results - 90 and 92 pts. in Harris Hip Score after 36 and 48 months accordingly. The fracture healed in the first patient. The evidence of fracture healing of the second patient was impossible to examine because of lack of X-ray. Conclusions. 1) The use of THR in the treatment of femoral shaft fractures with coexisting osteoarthritis gives a chance of simultaneous fracture treatment and joint replacement. 2) Fracture stabilization requires the use of metal plates and cables.  相似文献   
4.
Cultured bovine adrenal medullary chromaffin cells were stimulated with the secretogogues Ba2+ or carbamyl choline plus Ca2+ in the presence of a monospecific rabbit IgG fraction directed against bovine dopamine beta-hydroxylase. The anti-dopamine beta-hydroxylase was labeled either with fluorescent protein A or with a fluorescent second antibody to rabbit IgG. Stimulation produced a patchy cell surface distribution of fluorescence. There was no noticeable internalization of the fluorescence for up to 2 h. In similar experiments using fluorescent monovalent fragments (Fab) of the same monospecificidopamine-beta-hydroxylase IgG, a more uniform distribution of the fluorescence was observed. A few min after a 5 min period of stimulation with Ba2+, the fluorescence appeared to be on or near the cell surface; however, after 20 min or more it was distributed throughout the cytoplasm except that the cell nuclei were not labeled. Thus, dopamine beta-hydroxylase which appeared on the cell surface as a consequence of exocytosis was internalized in the presence of monovalent antibody fragments, but not in the presence of the divalent (polyclonal) antibody, presumably because endocytosis of dopamine beta-hydroxylase was inhibited by crosslinking of the dopamine beta-hydroxylase molecules. The internalized anti-dopamine beta-hydroxylase Fab fragments were found to reappear on the cell surface during a second secretory response. It is concluded that the interior of the chromaffin granule membrane, for which dopamine beta-hydroxylase is a marker, becomes exposed on the surface of the cell during secretion and that the membrane is then retrieved back into the cell where it can be re-used in a further secretory cycle.  相似文献   
5.
The authors present an algorithm for determining the stiffness of the bone tissue for individual ranges of bone density. The paper begins with the preparation and appropriate mechanical processing of samples from the bovine femur and their imaging using computed tomography and then processing DICOM files in the MIMICS system. During the processing of DICOM files, particular emphasis was placed on defining basic planes along the sides of the samples, which improved the representation of sample geometry in the models. The MIMICS system transformed DICOM images into voxel models from which the whole bone FE model was built in the next step. A single voxel represents the averaged density of the real sample in a very small finite volume. In the numerical model, it is represented by the HEX8 element, which is a cube. All voxels were divided into groups that were assigned average equivalent densities. Then, the previously prepared samples were loaded to failure in a three-point bending test. The force waveforms as a function of the deflection of samples were obtained, based on which the global stiffness of the entire sample was determined. To determine the stiffness of each averaged voxel density value, the authors used advanced optimization analyses, during which numerical analyses were carried out simultaneously, independently mapping six experimental tests. Ultimately, the use of genetic algorithms made it possible to select a set of stiffness parameters for which the error of mapping the global stiffness for all samples was the smallest. The discrepancies obtained were less than 5%, which the authors considered satisfactory by the authors for such a heterogeneous medium and for samples collected from different parts of the bone. Finally, the determined data were validated for the sample that was not involved in the correlation of material parameters. The stiffness was 7% lower than in the experimental test.  相似文献   
6.

Background

As estimated from the number of published studies, in Poland the research into the perinatal care experiences of women with low vision or total blindness remains limited.

Objectives

The purpose of the study was to fill this gap by investigating satisfaction with perinatal care received by women with visual impairment in four city hospitals in Warsaw, Poland, and to recommend, if required, modifications in midwives' education and care standards based on the women's perceptions and expectations.

Methods

Hour-long interviews were conducted between 30 August 2014 and 2 September 2015 with 16 blind or low vision women in perinatal care, audio-recorded and transcribed verbatim. The accounts were subsequently evaluated using the Interpretative Phenomenological Analysis (IPA) approach. Five major themes were pre-selected: perceived stigma and lack of affirmation for the interviewee's motherhood, accessibility of childbirth preparation, accessibility of perinatal care and hospital facilities, midwives' attitudes and the interviewees' expectations for care improvements.

Results

Overall, the accounts demonstrated the lack of satisfaction with the quality of perinatal care, including the childbirth preparation classes, hospital facilities and hospital staff approach as not actually meeting specific functional needs. They also suggested how the quality of care could be improved.

Conclusions

Specific standards and procedures for perinatal care for women who are blind or have low vision should be developed and introduced in clinical practice in Poland based on research into the experiences of these women. Also, the training of health care professionals should be modified and their attitudes changed to meet maternal needs.  相似文献   
7.
Virus Genes - Mink astrovirus infection remains a poorly understood disease entity, and the aetiological agent itself causes disease with a heterogeneous course, including gastrointestinal and...  相似文献   
8.
Background. The purpose of the study is to evaluate the risk of fractures in long bones with metastases based on intact cortical bone index (ICBI) and functional assessment.
Material and methods. We evaluate radiograms of 36 (25 fractures) and 86 patients (56 fractures) with the upper and lower extremity metastases, respectively. We measured on radiograms intact cortical bone index (ICBI) using the schedule K-G/K-J x100%, where is K-shaft diameter, G-size of destruction, J-bone marrow diameter above or below the metastases. We asses the extremity function by the ability to elevate and abduct it straight.
Results. We found that fracture occurs if the ICBI is lower than 46% and 40% in upper and lower extremity, respectively. 7 (5,7%) patients develop fracture despite higher ICBI. If the metastases are located in upper part of the femur and humerus and he/she can not elevate or abduct the extremity the fracture inevitably occurs.
Conclusions. Counting the ICBI and simple functional assessment allows to predict fracture in 94,3% of patients with long bone metastases.  相似文献   
9.
AIMS--To investigate the effect of pregnancy on serum concentrations of lipids, lipoproteins, and apolipoproteins. METHODS--Fasting serum concentrations of total cholesterol, triglyceride, low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), apolipoproteins AI, AII, and B, and lipoprotein (a) were measured in 178 women with normal glucose tolerance in the second and third trimesters of pregnancy and in a control group of 58 non-pregnant women of similar age. Data were analysed using the unpaired t test and by one-way analysis of variance. RESULTS--The pregnant women had significantly higher concentrations of total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, and apolipoproteins AI and B (p < 0.001) and apolipoprotein AII (p = 0.003) than the control women. The ratio of apolipoprotein B:apolipoprotein AI was significantly higher in the pregnant women than in the controls (p < 0.001), but the total cholesterol:HDL cholesterol ratio was not significantly different. No significant difference was found in the concentration of lipoprotein (a). CONCLUSIONS--Hyperlipidaemia is common in the second half of pregnancy. This may be a purely physiological response to pregnancy or it may be indicative of pathology in some women. These results warrant a follow up study to investigate whether the hyperlipidaemic response to pregnancy is variable and if so, whether it can predict future hyperlipidaemia in a manner analogous to that of impaired glucose tolerance during pregnancy, predicting non-insulin dependent diabetes in later life.  相似文献   
10.
Studies were undertaken to assess the ability of human polymerase alpha (pol alpha) and polymerase gamma (pol gamma) to incorporate 2'-fluoro- and 2'-O-methyldeoxynucleotides into DNA. In vitro DNA synthesis systems were used to detect incorporation and determine K(m) and V(max) for 2'-FdATP, 2'-FdUTP, 2'-FdCTP, 2'-FdGTP, 2'-O-MedATP, 2'-O-MedCTP, 2'-O-MedGTP, 2'-O-MedUTP, dUTP, UTP, and FIAUTP, in addition to normal deoxynucleotides. Pol alpha incorporated all 2'-FdNTPs except 2'-FdATP, but not 2'-O-MedNTPs. Pol gamma incorporated all 2'-FdNTPs, but not 2'-O-MedNTPs. In general, 2'-fluorine substitution decreased V(max)/K(m) 2'-FdUTP. Because kinetics of insertion of pol alpha can be affected by the nature of the primer, we examined the ability of pol alpha to polymerize 2'-fluoro- and 2'-O-MedATP and dGTP when elongating a primer synthesized by DNA primase. Under these conditions, both 2'-FdATP and 2'-FdGTP were polymerized, but 2'-O-MedATP and 2'-O-MedGTP were not. Primase alone could not readily polymerize these analogs into RNA primers. Previous studies showed that 2'-deoxy-2'-fluorocytosine (2'-FdC) is incorporated by several non-human DNA polymerases. The current studies showed that human polymerases can polymerize numerous 2'-FdNTPs but cannot polymerize 2'-O-MedNTPs.  相似文献   
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