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排序方式: 共有641条查询结果,搜索用时 15 毫秒
631.
OBJECTIVE: To evaluate the feasibility of obtaining standard echocardiographic views of the fetal heart during routine first-trimester screening and construct reference ranges for cardiac biometry at 11 + 0 to 13 + 6 weeks of gestation. METHODS: A cross-sectional study of 584 fetuses in an unselected population. Viable pregnancies with a crown-rump length (CRL) of 41-78 mm were included. Echocardiography was performed by a single obstetrician using a 5 to 7.5 MHz vaginal transducer. The course and outcome of pregnancies were recorded and information on the babies was obtained in all cases. RESULTS: A completely satisfactory visualization of the fetal heart structures was possible in 58% (43%, 56% and 62% at 11, 12 and 13 weeks, respectively). Reference ranges were constructed from the measurements of cardiac ventricles, their outflow tracts, and cardiothoracic circumference ratio in relation to CRL. CONCLUSION: Standard echocardiograhic views of the fetal heart can be obtained at 11 + 0 to 13 + 6 weeks of gestation using the transvaginal approach. New reference ranges were established for fetal cardiac biometry at 11 + 0 to 13 + 6 weeks of gestation. 相似文献
632.
Maternal haemodynamics in pre-eclampsia compared with normal pregnancy during caesarean delivery 总被引:1,自引:0,他引:1
Tihtonen K Kööbi T Yli-Hankala A Huhtala H Uotila J 《BJOG : an international journal of obstetrics and gynaecology》2006,113(6):657-663
Objective To determine how pre-eclampsia modifies maternal haemodynamics during caesarean delivery.
Design Prospective study.
Setting Tampere University Hospital, Finland.
Population Ten pre-eclamptic parturients and ten healthy parturients with uncomplicated pregnancies scheduled for elective caesarean section under spinal anaesthesia.
Methods Haemodynamic parameters were assessed by whole-body impedance cardiography noninvasively.
Main outcome measures Stroke index (SI), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and mean arterial pressure (MAP) were recorded before operation, continuously during caesarean section, during the period of dissipation of anaesthesia and on the second to fifth postpartum day.
Results Baseline haemodynamics in women with pre-eclampsia differed significantly from healthy women in higher SVRI and MAP and lower SI and CI. In women with pre-eclampsia, preload infusion increased both SI and HR, causing a significant rise in CI, while in healthy parturients, only HR rose. In both the groups, spinal blockade reduced SVRI but CI remained stable. At the moment of delivery, CI increased in both groups. In uncomplicated pregnancies, both SI and HR increased, but in women with pre-eclampsia, SI was not altered and the rise in CI was due to an increase in HR only. After the reversal of anaesthesia, haemodynamics in the control group returned to baseline values, whereas in women with pre-eclampsia, SI and CI fell to levels that were significantly lower than the levels observed before surgery.
Conclusions In women with pre-eclampsia, inability to increase SI at the moment of delivery may suggest dysfunction of the left ventricle to adapt to volume load caused by delivery and prompts concern for the increased risk of pulmonary oedema. 相似文献
Design Prospective study.
Setting Tampere University Hospital, Finland.
Population Ten pre-eclamptic parturients and ten healthy parturients with uncomplicated pregnancies scheduled for elective caesarean section under spinal anaesthesia.
Methods Haemodynamic parameters were assessed by whole-body impedance cardiography noninvasively.
Main outcome measures Stroke index (SI), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and mean arterial pressure (MAP) were recorded before operation, continuously during caesarean section, during the period of dissipation of anaesthesia and on the second to fifth postpartum day.
Results Baseline haemodynamics in women with pre-eclampsia differed significantly from healthy women in higher SVRI and MAP and lower SI and CI. In women with pre-eclampsia, preload infusion increased both SI and HR, causing a significant rise in CI, while in healthy parturients, only HR rose. In both the groups, spinal blockade reduced SVRI but CI remained stable. At the moment of delivery, CI increased in both groups. In uncomplicated pregnancies, both SI and HR increased, but in women with pre-eclampsia, SI was not altered and the rise in CI was due to an increase in HR only. After the reversal of anaesthesia, haemodynamics in the control group returned to baseline values, whereas in women with pre-eclampsia, SI and CI fell to levels that were significantly lower than the levels observed before surgery.
Conclusions In women with pre-eclampsia, inability to increase SI at the moment of delivery may suggest dysfunction of the left ventricle to adapt to volume load caused by delivery and prompts concern for the increased risk of pulmonary oedema. 相似文献
633.
RATIONALE: Perphenazine, a classical antipsychotic drug, has the potential to induce extrapyramidal side effects (EPS). Dopaminergic and serotonergic pathways are involved in the therapeutic and adverse effects of the drug. OBJECTIVES: To evaluate the impact of polymorphisms in the dopamine D(2) and D(3) and serotonin 2A and 2C receptor genes (DRD2, DRD3, HTR2A, and HTR2C) on short-term effects of perphenazine monotherapy in schizophrenic patients. MATERIALS AND METHODS: Forty-seven Estonian inpatients were evaluated before and after 4-6 weeks of treatment by Simpson-Angus rating scale, Barnes scale, and Positive and Negative Symptom Scale. Genotyping was performed for common DRD2, DRD3, HTR2A, and HTR2C gene polymorphisms, previously reported to influence receptor expression and/or function. RESULTS: Most of the patients (n = 37) responded to the treatment and no significant association was observed between the polymorphisms and antipsychotic response. The 102C allele of HTR2A and the -697C and 23Ser alleles of HTR2C were more frequent among patients with EPS (n = 25) compared to patients without EPS (n = 22) (p = 0.02, 0.01, and 0.02, respectively). The difference between patients with and without EPS in variant allele frequencies remained significant after multiple model analyses including age, gender, and duration of antipsychotic treatment as covariants. There was no significant association between EPS occurrence and polymorphisms in the DRD2 and DRD3 genes. CONCLUSIONS: An association was observed between polymorphisms in HTR2A and HTR2C genes and occurrence of acute EPS in schizophrenic patients treated with perphenazine monotherapy. Larger study populations are needed to confirm our findings. 相似文献
634.
Harju JA Eskola MJ Huhtala H Niemelä KO Karhunen PJ Nikus KC 《Journal of electrocardiology》2006,39(4):368-368.e5
Background
ST-segment elevation in the right-sided chest lead V4R in inferior wall myocardial infarction is recognized as a sign of proximal occlusion of the right coronary artery with evolving right ventricular myocardial infarction. Our objective is to study how often lead V4R is recorded in clinical practice and how this might be associated with use of reperfusion therapy and outcome of patients.Methods
Recording of lead V4R in 814 consecutive patients with acute myocardial infarction, administration of therapy, and outcome of the patients during a median follow-up of 285 days (174-313 days) were studied.Results
V4R was recorded in 52% of patients with inferior ST-elevation myocardial infarction. Patients with V4R recorded were more likely to receive fibrinolytic therapy compared with patients without recording (65% vs 51%; P = .035). In multivariate analysis, recording of lead V4R (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.2; P = .006), along with age (P < .001), previous myocardial infarction (OR 2.2, 95% CI 1.3-3.5; P = .002), and diabetes (OR 3.9, 95% CI 1.1-2.4; P = .03) correlated to the use of reperfusion therapy. Patients with lead V4R recorded had less (P = .055) reinfarction, unstable angina, stroke, and/or death during follow-up.Conclusions
Lead V4R was recorded in only half of patients with inferior ST-elevation myocardial infarction. Patients with V4R recorded were more likely to receive thrombolytic therapy than those without recording of the additional chest lead. 相似文献635.
Seppanen M Meri S Notkola IL Seppala IJ Hiltunen-Back E Sarvas H Lappalainen M Valimaa H Palikhe A Valtonen VV Lokki ML 《The Journal of infectious diseases》2006,194(5):571-578
BACKGROUND: Immunogenetic factors predisposing to recurrent genital herpes remain poorly characterized. METHODS: In a prospective case-control study, 52 consecutive patients with frequently recurring outbreaks of genital herpes were compared with 80 herpes simplex virus (HSV)-seropositive (types 1 and 2) and 70 HSV-seronegative control subjects. Immunoglobulins (Igs), type-specific anti-HSV-2 IgG and IgG subclass antibodies against glycoprotein G, levels of C3 and C4, and classical pathway hemolytic complement activity were measured, and IgG1 and IgG3 allotyping; C4 immunophenotyping; C4* real-time polymerase chain reaction (PCR) genotyping; and HLA-A*, B*, and DR* typing were performed. RESULTS: The G3m(g),G1m(a/a(x)) haplotype was more frequent in patients than in HSV-seronegative control subjects (P=.047). Compared with all control subjects, low levels of total IgG1 (odds ratio [OR], 4.9 [95% confidence interval {CI}, 2.0-12.5]; P=.001) and IgG3 (OR 3.6 [95% CI 1.7-7.8]; P=.001), but not of anti-HSV-2 antibodies, were associated with recurrences. Levels of complement were lowest in patients. The C4* null type was negatively associated with neuralgia (OR, 0.2 [95% CI, 0.06-0.81]; P=.022). CONCLUSIONS: Low levels of antibody-dependent cellular cytotoxicity-mediating IgG1 and IgG3 antibodies, partly dependent of allotype, may predispose to recurrent genital herpes. Antibodies produced by T helper type 1 responses, potentially against an unknown epitope, appear to be relevant in recurrences. In patients, C4* deficiencies are associated with protection from herpetic neuralgias, possibly through reduced inflammation. 相似文献
636.
Our aim was to study how nurses interpret patient autonomy in end-of-life decision making. This study built on our previous quantitative study, which evaluated the experiences of and views on end-of-life decision making of a representative sample of Finnish nurses taken from the whole country. We performed qualitative interviews with 17 nurses and analysed these using discourse analysis. In their talk, the nurses demonstrated three different discourses, namely, the 'supporter', the 'analyst' and the 'practical' discourses, each of which outlined a certain position for patients and relatives, and a certain identity for the nurses in end-of-life decision making. The nurses' talk showed notable differences when compared with that of physicians, highlighting the differences that take place in respect of the image of a person's work, professional culture, professional identification and responsibilities. An important finding was that the nurses often described their participation in end-of-life decision making in terms of indirect influence. 相似文献
637.
Sihvonen S Korpela M Mustonen J Huhtala H Karstila K Pasternack A 《The Journal of rheumatology》2006,33(9):1740-1746
OBJECTIVE: To evaluate mortality and causes of death in patients with rheumatoid arthritis (RA) treated with low-dose oral glucocorticoids. METHODS: Mortality was analyzed in population-based data of 604 patients with RA. In the original study in 1988, state of general health, severity of RA, and treatment including the use of oral glucocorticoids were recorded. In 1999 vital status and causes of death were evaluated. Mortality in patients with RA who had not received glucocorticoids (Group A, n = 209) was compared to that in patients treated with glucocorticoids for less than 10 years (Group B, n = 276) or for more than 10 years (Group C, n = 119). RESULTS: From onset of RA to 1999, 395 (65%) patients had been treated with oral glucocorticoids. In 1999 a total of 160 (26%) patients had died, 23% of patients in Group A, 21% in Group B, and 45% in Group C. In multivariate Cox regression analysis, male sex (hazard ratio 2.50; 95% CI 1.74-3.59), impaired functional capacity by Health Assessment Questionnaire (HR 2.11; 95% CI 1.65-2.96), heart failure (HR 1.96; 95% CI 1.36-2.84), and diabetes (HR 1.87; 95% CI 1.17-3.01) predicted increased mortality. In the same analysis glucocorticoid treatment for 1 year increased the mortality risk by 14% (HR 1.14; 95% CI 0.98-1.27, p = 0.057) and treatment over 10 years by 69% (HR 1.69; 95% CI 1.12-2.56, p = 0.011) compared to RA patients without treatment. The major cause of death was cardiovascular disease in all groups, but infections and intestinal perforations due to amyloidosis were more frequent in patients with long-lasting glucocorticoid therapy. Lymphomas were more frequent in all patients treated with glucocorticoids (Groups B and C) than in those not receiving glucocorticoids. CONCLUSION: Patients with RA treated with low-dose oral glucocorticoids for more than 10 years had increased mortality compared to those who did not receive glucocorticoids or whose duration of treatment was less than 10 years. The increased mortality was related mainly to infections and complications caused by systemic amyloidosis. 相似文献
638.
Vesa Juvonen Eeva Nikoskelainen Tarja Lamminen Maila Penttinen Pertti Aula Marja-Liisa Savontaus 《Human mutation》1997,9(5):412-417
Leber hereditary optic neuropathy (LHON) is a maternally inherited eye disease most commonly caused by mitochondrial DNA (mtDNA) point mutation at position 11778, 3460, or 14484. Approximately 14% of families show heteroplasmy for the pathogenic mutations but little is known about the mutational burden in different tissues of these heteroplasmic individuals. Consequently, estimating the risks of visual loss is difficult. This study presents quantitative mutation analyses of tissues representing all embryonal layers in two families heteroplasmic for the 11778 mutation. These analyses show that a high amount of mutated mtDNA in leukocytes is correlated with a high proportion of mutated mtDNA in other tissues. Hum Mutat 9:412–417, 1997. © 1997 Wiley-Liss, Inc. 相似文献
639.
Paakkala A Lempinen L Paakkala T Huhtala H Mustonen J 《European Journal of Internal Medicine》2004,15(5):284-290
BACKGROUND: This study was designed to evaluate radiological findings in chest and sinus radiographs and renal ultrasound (US) in patients with nephropathia epidemica (NE) and to determine whether changes in these medical images are related to each other or to the clinical course of NE. METHODS: Radiological findings and clinical course were studied in 380 hospital-treated NE patients during the years 1982-1998. RESULTS: In 35% of the patients there were clear changes in chest radiographs. Pleural effusion, atelectasis, and interstitial infiltration were the most common X-ray findings. Forty-seven percent had changes in renal US, with increased cortical echoicity and cortical swelling being the most common findings. Thirty-three percent of the patients with clinical symptoms of sinusitis had changes in sinus radiographs. Abnormal findings on chest radiographs were clearly associated with fluid volume overload, high blood pressure level, leukocytosis, degree of clinical renal insufficiency, and thrombocytopenia. Abnormal findings in renal US were associated to some extent with fluid volume overload and degree of clinical renal insufficiency. CONCLUSIONS: Some 35% of patients had clear changes in chest radiographs and 47% showed changes in renal US. Abnormal findings in chest radiographs were clearly associated, and abnormal findings in renal US were associated to some extent, with the severity of the clinical course of NE. 相似文献
640.
Fernández M Keyriläinen J Serimaa R Torkkeli M Karjalainen-Lindsberg ML Leidenius M von Smitten K Tenhunen M Fiedler S Bravin A Weiss TM Suortti P 《Physics in medicine and biology》2005,50(13):2991-3006
Twenty-eight human breast tumour specimens were studied with small-angle x-ray scattering (SAXS), and 10 of those were imaged by the diffraction enhanced x-ray imaging (DEI) technique. The sample diameter was 20 mm and the thickness 1 mm. Two examples of ductal carcinoma are illustrated by histology images, DEI, and maps of the collagen d-spacing and scattered intensity in the Porod regime, which characterize the SAXS patterns from collagen-rich regions of the samples. Histo-pathology reveals the cancer-invaded regions, and the maps of the SAXS parameters show that in these regions the scattering signal differs significantly from scattering by the surrounding tissue, indicating a degradation of the collagen structure in the invaded regions. The DEI images show the borders between collagen and adipose tissue and provide a co-ordinate system for tissue mapping by SAXS. In addition, degradation of the collagen structure in an invaded region is revealed by fading contrast of the DEI refraction image. The 28 samples include fresh, defrosted tissue and formalin-fixed tissue. The d-values with their standard deviations are given. In the fresh samples there is a systematic 0.76% increase of the d-value in the invaded regions, averaged over 11 samples. Only intra-sample comparisons are made for the formalin-fixed samples, and with a long fixation time, the difference in the d-value stabilizes at about 0.7%. The correspondence between the DEI images, the SAXS maps and the histo-pathology suggests that definitive information on tumour growth and malignancy is obtained by combining these x-ray methods. 相似文献