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31.
Rationale: Late onset type 1 alcoholism has been suggested to be associated with an underlying dopaminergic defect. Therefore, it is
relevant to study both postsynaptic D2-receptor and presynaptic dopamine transporter (DAT) densities among alcoholics. Objective: We investigated DAT densities, along with striatal and extrastriatal dopamine D2-receptor densities, in nine non-violent late-onset male alcoholics, who had no major mental disorder nor antisocial personality
disorder (ASPD), and nine healthy controls. Methods: [123I]PE2I and [123I]epidepride were used in SPECT imaging. Results: DAT occupancy ratios (striatum/cerebellum) were significantly lower among alcoholics than in controls. Extrastriatal D2-receptor occupancy ratios (temporal pole/cerebellum) were not significantly different between the groups. Conclusions: Striatal presynaptic DAT densities are decreased among type 1 alcoholics, and this finding is not associated with recent
alcohol abuse.
Received: 22 March 1999 / Final version: 25 June 1999 相似文献
32.
Pekkarinen J Alho A Lepistö J Ylikoski M Ylinen P Paavilainen T 《The Journal of bone and joint surgery. British volume》2000,82(1):103-107
We have reviewed retrospectively 68 revisions of the femoral component in arthroplasties of the hip in 65 patients, using impaction bone grafting, at a median of three years (1 month to 6 years). We employed the cemented Exeter X-Change technique in 36 patients and the uncemented Bi-Metric allografting method in 32. The 37 bone defects were grade 3 or grade 4 on the Endo-Klinik classification. The Mayo hip score improved from a mean of 32 (SD +/- 18) to 62 (SD +/- 15). Most (25) of the 34 complications occurred in grade-3 and grade-4 defects; nine were intraoperative diaphyseal fractures and eight fractures of the greater trochanter. All the fractures united. The risk of intraoperative fracture was prevented by supporting the bone with wires in 16 hips, with reinforcement mesh in 18 and by a plate in six. Early migration of the stem of more than 10 mm during the first year indicated rotational instability; it occurred in three cases. In difficult revision cases with large defects of the femoral bone, bone-impaction techniques carry a high risk of complications. 相似文献
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34.
Jouko Hartikainen Jukka Antila Matti Varpula Pauli Puukka Heikki Sepp Reidar Grnman 《The Laryngoscope》1998,108(12):1861-1866
Objectives and Study Design: The advent of the rigid endonasal endoscope and the development of functional endoscopic sinus surgery (FESS) technique have awakened interest in an endonasal endoscopic dacryocystorhinostomy (EESC-DCR) in treating nasolacrimal obstruction. This prospective, randomized study compares EESC-DCR with traditional external dacryocystorhinostomy (EXT-DCR) for their success rates, surgical duration, and postoperative symptoms. Patients and Methods: Sixty-four cases in 60 patients with primary acquired nasolacrimal sac or duct obstruction were divided into two subgroups by symptoms (simple epiphora/ chronic dacryocystitis). These patients were randomized within both subgroups into two operation groups. Altogether 32 EESC-DCRs and 32 EXT-DCRs were performed. The final follow-up visit was at 1 year. The patency of the lacrimal passage was investigated by irrigation and patients were questioned about their symptoms. Results: The success rate at 1 year after surgery was 75% for EESC-DCR and 91% for EXT-DCR after primary surgery. The difference was not statistically significant (P = .18). The success rate after secondary surgery with a follow-up time of 1 year was 97% in both study groups. The average duration for EESC-DCR was 38 minutes, and 78 minutes for EXT-DCR, (P < .001). Conclusions: EXT-DCR, when compared with EESC-DCR, appears to give a higher, although not statistically significant, primary success rate, but the secondary success rates are equal, indicating that these two different DCR techniques are acceptable alternatives. 相似文献
35.
Jukka Uotila Consultant Tiina Solakivi Research Scientist Olli Jaakkola Senior Lecturer † Risto Tuimala Senior Lecturer Terho Lehtimaki Senior Lecturer † 《BJOG : an international journal of obstetrics and gynaecology》1998,105(10):1113-1117
Objective To measure auto-antibodies against oxidatively modified low density lipoprotein (LDL) in pre-eclamptic pregnancies using two different techniques.
Design Clinical study comparing pre-eclamptic and normal pregnancies.
Setting Tampere University Hospital, Finland.
Population Twenty-one primigravidae with pre-eclampsia and 13 healthy, normotensive primigravidae as controls.
Methods The serum titers of antibodies against both malondialdehyde-modified and copper-oxidised LDL (MDA-LDL and copper-ox LDL) were analysed and related to parameters reflecting the severity of pre-eclampsia.
Results There was a positive correlation ( r = 0.58 ) between antibodies against MDA-LDL and copper-ox LDL in women with pre-eclampsia but not in healthy pregnant controls. The antibody levels against copper-ox LDL, but not against MDA-LDL, were higher in women with pre-eclampsia than in women with a normal pregnancy ( P < 0.01 ). While the antibody titers against copper-ox LDL did not correlate with any parameter reflecting the severity of pre-eclampsia, those against MDA-LDL showed a positive correlation with the level of diastolic blood pressure ( r = 0.54 ) and a negative correlation with platelet count ( r = 461 ) in women with pre-eclampsia.
Conclusions There are increased titers of serum autoantibodies against copper-oxidised LDL in pre-eclampsia, which may reflect enhanced lipid peroxidation involving circulating lipoproteins. 相似文献
Design Clinical study comparing pre-eclamptic and normal pregnancies.
Setting Tampere University Hospital, Finland.
Population Twenty-one primigravidae with pre-eclampsia and 13 healthy, normotensive primigravidae as controls.
Methods The serum titers of antibodies against both malondialdehyde-modified and copper-oxidised LDL (MDA-LDL and copper-ox LDL) were analysed and related to parameters reflecting the severity of pre-eclampsia.
Results There was a positive correlation ( r = 0.58 ) between antibodies against MDA-LDL and copper-ox LDL in women with pre-eclampsia but not in healthy pregnant controls. The antibody levels against copper-ox LDL, but not against MDA-LDL, were higher in women with pre-eclampsia than in women with a normal pregnancy ( P < 0.01 ). While the antibody titers against copper-ox LDL did not correlate with any parameter reflecting the severity of pre-eclampsia, those against MDA-LDL showed a positive correlation with the level of diastolic blood pressure ( r = 0.54 ) and a negative correlation with platelet count ( r = 461 ) in women with pre-eclampsia.
Conclusions There are increased titers of serum autoantibodies against copper-oxidised LDL in pre-eclampsia, which may reflect enhanced lipid peroxidation involving circulating lipoproteins. 相似文献
36.
Janne L?hdesm?ki Jukka Sallinen Ewen MacDonald Mika Scheinin 《Neuropsychopharmacology》2004,29(7):1282-1293
Amphetamines are commonly used to treat attention-deficit hyperactivity disorder, but are also widely abused. They are employed in schizophrenia-related animal models as they disrupt the prepulse inhibition (PPI) of the acoustic startle response. The behavioral effects of amphetamines have mainly been attributed to changes in dopamine transmission, but they also involve increases in the synaptic concentrations of norepinephrine (NE). alpha2-Adrenoceptors (alpha2-ARs) regulate the excitability and transmitter release of brain monoaminergic neurons mainly as inhibitory presynaptic auto- and heteroreceptors. Modulation of acoustic startle and its PPI by the alpha2A-AR subtype was investigated with mice lacking the alpha2A-AR (alpha2A-KO) and their wild-type (WT) controls, without drugs and after administration of the alpha2-AR agonist dexmedetomidine or the antagonist atipamezole. The interaction of D-amphetamine (D-amph) and the alpha2-AR-noradrenergic neuronal system in modulating startle reactivity and in regulating brain monoamine metabolism was assessed as the behavioral and neurochemical responses to D-amph alone, or to the combination of D-amph and dexmedetomidine or atipamezole. alpha2A-KO mice were supersensitive to both neurochemical and behavioral effects of D-amph. Brain NE stores of alpha2A-KO mice were depleted by D-amph, revealing the alpha2A-AR as essential in modulating the actions of D-amph. Also, increased startle responses and more pronounced disruption of PPI were noted in D-amph-treated alpha2A-KO mice. alpha2A-AR also appeared to be responsible for the startle-modulating effects of alpha2-AR drugs, since the startle attenuation after the alpha2-AR agonist dexmedetomidine was absent in alpha2A-KO mice, and the alpha2-AR antagonist atipamezole had opposite effects on the startle reflex in alpha2A-KO and WT mice. 相似文献
37.
38.
Jukka Juutilainen Esa Läära Keijo Saali 《International journal of radiation biology》2013,89(5):787-793
SummaryChick embryos were exposed to sinusoidally oscillating 50 Hz magnetic fields during their first 2 days of development. In the first series of experiments magnetic field strengths of 0·1, 0·3, 1 and 10 A/m were used. The percentage of abnormal embryos (%AE) was 16 per cent in the sham-exposed control group. %AE was increased at 1 A/m (29 per cent) and 10 A/m (32 per cent), but not at 0·1 A/m (16 per cent) or 0·3 A/m (14 per cent). In the second series of experiments field strengths of 0·4, 0·6, 0·9 and 1·35 A/m were used. %AE was 17 per cent in the control group, 10 per cent at 0·4 A/m, 19 per cent at 0·6 A/m, 17 per cent at 0·9 A/m and 36 per cent at 1·35 A/m. Only the 1·35 A/m group was significantly different from the controls. The results of this study suggest that exposure of chick embryos to a 50 Hz magnetic field causes abnormal development, and that no abnormalities are induced below a threshold between 0·9 and 1 A/m. 相似文献
39.
An in vitro degradation study of three bioresorbable glass fiber-reinforced poly(l-lactide-co-dl-lactide) (PLDLA) composites was carried out in simulated body fluid (SBF), to simulate body conditions, and deionized water, to evaluate the nature of the degradation products. The changes in mechanical and chemical properties were systematically characterized over 52 weeks dissolution time to determine the degradation mechanism and investigate strength retention by the bioresorbable glass fiber-reinforced PLDLA composite. The degradation mechanism was found to be a combination of surface and bulk erosion and does not follow the typical core-accelerated degradation mechanism of poly(α-hydroxyacids). Strength retention by bioresorbable glass fiber-reinforced PLDLA composites can be tailored by changing the oxide composition of the glass fibers, but the structure–property relationship of the glass fibers has to be understood and controlled so that the phenomenon of ion leaching can be utilized to control the degradation rate. Therefore, these high performance composites are likely to open up several new possibilities for utilizing resorbable materials in clinical applications which could not be realized in the past. 相似文献
40.
Aims: In this study, we highlight the identities and actions of women with a problem-drinking relative by analysing autobiographies of women born between the 1920s and the 1950s. We ask how women describe their relationship and the problems arising because of a significant other’s drinking and how they cope with these problems. Methods: In the analysis, we pay attention to the power dynamics between family members. We, first, trace what kind of positions or identities the protagonists take in relation to the drinker. Second, we examine what kinds of harms and emotional reactions significant other’s drinking causes. Third, we consider how writers identify or take distance from events described in the autobiographies. Findings: Our analysis reveals four main identities and coping strategies: the positions of victim, helper, boundary setter and fighter. The victim and helper positions often entail women’s weakness and oppressed role, while the positions of boundary setter and fighter express women’s own power and reflexivity in action. Conclusions: Knowledge of the identities and coping strategies is important for understanding the power aspects of a relationship and developing appropriate support for women suffering from family member’s drinking. 相似文献