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91.
HM Farsi 《Canadian Metallurgical Quarterly》1996,78(1):90-92
Examination of the long-term relation of a single fibrinogen determination to initial and recurrent atherosclerotic cardiovascular events over 20 years of follow-up revealed a powerful and comparably independent impact on initial events in both sexes but an influence on recurrent events only in men. 相似文献
92.
Between 1985 and 1994, 1223 patients with malleolar fractures of the ankle were treated by open reduction and internal fixation with absorbable pins and screws, of whom 74 (6.1%) had an obvious inflammatory foreign-body reaction to the implants. Of these 74, ten later developed moderate to severe osteoarthritis of the ankle despite no evidence of incongruity of the articular surface. The implants used in these patients were made from polyglycolide, polylactide or glycolide-lactide copolymer. The joint damage seemed to be due to polymeric debris entering the articular cavity through an osteolytic extension of an implant track. The ten patients had a long clinical course which included a vigorous local foreign-body reaction, synovial irritation and subsequent degeneration. At a follow-up of three to nine years, ankle arthrodesis had been necessary in two patients and is being considered for another two. The incidence of these changes in the whole series was 0.8%, which is not high, but awareness of this possible late complication is essential. 相似文献
93.
Two ampullary epithelial properties necessary for electroreception were used to identify the types of ion channels and transporters found in apical and basal membranes of ampullary receptor cells of skates and to assess their individual role under voltage-clamp conditions. The two essential properties are (1) a steady-state negative conductance generated in apical membranes and (2) a small, spontaneous current oscillation originating in basal membranes (Lu and Fishman, 1995). The effects of pharmacological agents and ion substitutions on these properties were evaluated from transorgan or transepithelial complex admittance determinations in the frequency range 0.125 to 50 Hz measured in individual, isolated ampullary organs. In apical membranes, L-type Ca channels were found to be responsible for generation of the steady-state negative conductance. In basal membranes, K and Ca-dependent Cl (Cl(Ca)) channels were demonstrated to contribute to a net positive membrane conductance. L-type Ca channels were also evident in basal membranes and are thought to function in synaptic transmission from the electroreceptive epithelium to the primary afferent nerve. In addition to ion channels in basal membranes, two transporters (Na+/K+ pump and Na(+)-Ca+ exchanger) were apparent. Rapid (minutes) cessation of the current oscillation after blockage of any of the basal ion channels (Ca, Cl(Ca), K) suggests critical involvement of each of these channel types in the generation of the oscillation. Suppression of either Na+/K+ transport or Na(+)-Ca2+ exchange also eliminated the oscillation but at a slower rate, indicating an indirect effect. 相似文献
94.
C Schmid M Deng D Hammel M Weyand HM Loick HH Scheld 《Canadian Metallurgical Quarterly》1998,17(10):1024-1028
BACKGROUND: The risk and outcome in patients undergoing left ventricular assist device (LVAD) implantation on an emergency basis is still unclear. METHODS: Since April 1993, 40 patients received a Novacor and 8 patients a Heartmate LVAD in our institution. Patients with emergency LVAD placement were compared with the remainder in a retrospective manner. Parameters studied included underlying heart disease, preimplantation dysfunction of kidney, liver, lung, and cerebrum, interval of mechanical support, outcome, and complications. RESULTS: Patients with emergency LVAD placement predominantly were seen with postcardiotomy heart failure (47%) or acute myocarditis (20%) (group A) whereas elective and urgent candidates for LVAD implantation mainly had dilative cardiomyopathy (67%) or ischemic heart disease (30%) (group B). The incidence of secondary organ failure was significantly higher for all organs in group A patients (p < .01). Mean support interval in patients who underwent emergency LVAD implantation was lower (74+/-79 days vs 115+/-80 days), and fewer patients could be forwarded to heart transplantation in this group (22% vs 78%, p < .01). Moreover, bleeding complications were increased in group A (66% vs 30%, p < .01), but not thromboembolism and infection. CONCLUSION: In conclusion, the overall success rate after emergency LVAD implantation was lower, with bleeding being the most frequent complication. To achieve acceptable outcomes in disastrous situations, LVADs should be placed as early as possible. 相似文献
95.
96.
PJ Franaszczuk GK Bergey PJ Durka HM Eisenberg 《Canadian Metallurgical Quarterly》1998,106(6):513-521
A Spanish-language questionnaire designed for measuring the impact of asthma on quality of life in adults was developed. It was derived, by the application of a rigorous translation protocol, from a previously validated, English-language Asthma Quality of Life (AQL) questionnaire which had been developed in Australia. The aim of this study was to evaluate the psychometric properties of the Spanish AQL questionnaire using a cross-sectional and longitudinal design. Two hundred ninety-four clinically stable subjects with asthma (168 women, mean baseline forced expiratory volume in 1 sec [FEV1] = 85% predicted), aged 17-70, attended for the initial baseline assessment. All subjects completed the AQL questionnaire and a full history and physical examination were performed. The clinical assessment of severity was based on the classification recommended by the Global Initiative on Asthma (GINA). One week after the initial assessment subjects completed the AQL questionnaire for a second time. Six months later, subjects were assessed clinically and completed all the assessment measures at baseline. Principal components analysis of the AQL questionnaire responses at the baseline visit revealed a structure that was almost identical to that seen in the original English-language questionnaire. The questionnaire was shown to be internally consistent (Cronbach's alpha 0.91 for total score and 0.80-0.86 for the four subscales) and repeatable (intraclass correlation coefficient 0.91 for the total scale and 0.78-0.92 for the subscales). The finding of expected strong correlations with the subject's global assessment of severity (p = 0.70) and dyspnea (p = 0.63), a weak inverse correlation with FEV1 (p = -0.17), and good discrimination among the four GINA severity categories (F3,291 = 37.16, p < 0.0001) supports the construct validity of the questionnaire. AQL scores increased with age (p = 0.31) and were higher in women (p < 0.005). The AQL was responsive to both improvement (mean change 1.02, p < 0.0001) and deterioration (mean change -1.13, p < 0.001) in the severity of asthma over a 6-month period. This disease-specific, Spanish-language AQL questionnaire was shown to have sound psychometric properties which make it suitable for use in cross-sectional or longitudinal studies where it is appropriate to assess the impact of asthma on the quality of life of individual patients. 相似文献
97.
We studied the effect of inhaled nitric oxide (NO) on 80 patients who had undergone cardiac surgery in our center. The indications for receiving NO inhalation and the number of patients were as follows: Pp/Ps > 0.5 for pulmonary hypertension (PH) (n = 32; 21 children and 11 adults), severe PH crisis (n = 9), high pulmonary vascular tone (Glenn pressure more than 18 mm Hg after bidirectional Glenn operation) or arterial oxygen saturation (SaO2) less than 70% despite an FiO2 of 1.0 after Blalock-Taussig shunt (n = 6), mean pulmonary artery pressure (PAP) > 15 mm Hg and transpulmonary gradient (TPG) (mean PAP - left atrial pressure [LAP]) > 8 mm Hg after Fontan-type operation (n = 18), elevated pulmonary vascular tone (mean PAP > 30 mm Hg and left ventricular assist system [LVAS] flow rate < 2.5 L/min/m2) in patients with LVAS (n = 3), and impaired oxygenation (PaO2/FiO2 < 100 under positive end-expiratory pressure [PEEP] > 5 cm H2O) (n = 12). Low dose inhaled NO (10 ppm) had the following effects. In adult PH patients, it significantly reduced the mean PAP (from 37.3 to 27.0 mm Hg; average values are given) and increased the mean systemic arterial pressure (SAP) (64.7 to 75.3 mm Hg). In infant PH patients, it increased the mean SAP (51.8 to 56.1 mm Hg). In patients with a PH crisis, it significantly reduced the central venous pressure (CVP) (13.3 to 8.8 mm Hg) while increasing both the mean SAP (49.4 to 57.9 mm Hg) and PaO2/FiO2 (135 to 206). In patients after a Fontan-type operation, it significantly reduced the mean PAP (16.8 to 13.8 mm Hg) and TPG (9.5 to 5.8 mm Hg). In patients under LVAS, it reduced the CVP (11.7 to 8.0 mm Hg) and mean PAP (32.0 to 24.7 mm Hg). In impaired oxygenation patients, PaO2/FiO2 was increased (75 to 106). Sixty-five patients were all followed for 2.0-4.3 years (average, 3.1 years). All 65 patients remained free from oxygen requirement, and possible chronic adverse effects including the occurrence of malignant tumors or chronic inflammation in the respiratory tract were not observed. 相似文献
98.
MY Chiang D Misner G Kempermann T Schikorski V Giguère HM Sucov FH Gage CF Stevens RM Evans 《Canadian Metallurgical Quarterly》1998,21(6):1353-1361
Hippocampal long-term potentiation (LTP) and long-term depression (LTD) are the most widely studied forms of synaptic plasticity thought to underlie spatial learning and memory. We report here that RARbeta deficiency in mice virtually eliminates hippocampal CA1 LTP and LTD. It also results in substantial performance deficits in spatial learning and memory tasks. Surprisingly, RXRgamma null mice exhibit a distinct phenotype in which LTD is lost whereas LTP is normal. Thus, while retinoid receptors contribute to both LTP and LTD, they do so in different ways. These findings not only genetically uncouple LTP and LTD but also reveal a novel and unexpected role for vitamin A in higher cognitive functions. 相似文献
99.
JH Tuerlings MJ Ligtenberg JA Kremer M Siers EJ Meuleman DD Braat LH Hoefsloot HM Merkus HG Brunner 《Canadian Metallurgical Quarterly》1998,13(8):2098-2101
Follicle stimulating hormone (FSH) is considered to be essential for spermatogenesis. Therefore, genetic abnormalities of FSH signalling on testicular Sertoli cells would be expected to affect sperm production negatively in males. Inactivating FSH receptor mutations have been reported earlier in both males and females. All affected males had elevated FSH serum concentrations and abnormal sperm parameters. We postulated that inactivating FSH receptor mutations might be a cause of oligozoospermia or azoospermia and reviewed the clinical data of 151 male intracytoplasmic sperm injection (ICSI) candidates with special attention to FSH serum concentrations. The exclusion criteria for mutation screening of the FSH receptor gene were: a history of operative sterilization or testicular malignancy, congenital abnormality other than cryptorchidism, and a chromosomal aberration or a Y-chromosome microdeletion. The inclusion criteria were: male (ICSI candidate) with azoospermia or oligoasthenoteratozoospermia (OAT) and elevated FSH serum concentrations. In total, 23 males with OAT and five males with azoospermia were tested for mutations of the coding sequences and the intron-exon boundaries of the FSH receptor gene by polymerase chain reaction (PCR) followed by single strand conformation polymorphism analysis (SSCP). Neutral polymorphisms were readily detected using this technique in both probands and controls. None of the 28 selected patients showed a pathogenic FSH receptor mutation. Mutations in the FSH receptor gene are not a common cause of infertility in ICSI candidates. 相似文献
100.
The Ilizarov method has broad applications for the generation of bone and soft tissue via an external fixator composed of small pins, tensional wires, rings, hinges and distractors. The success of the technique depends on adherence to Ilizarov's principles of tension-stress phenomenon: preservation of the tissues' blood supply, frequent distraction in small increments, and full function of the extremity. 相似文献