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731.
732.
When a pregnant woman presented with a syndrome suggesting obstruction and fever together with jaundice and oliguria the authors remembered the difficulty of clinical diagnosis and the biology of pancreatitis. They studied the connection of this condition with pregnancy, its pathogenesis, its prognosis and its treatment, as well as the various factors that were favourable (treatment with diuretics, the right ovarian vein syndrome). 相似文献
733.
JF Nielsen 《Canadian Metallurgical Quarterly》1996,13(5):423-434
Motor evoked potentials were recorded from the first dorsal interosseous muscle on the dominant side evoked by transcranial magnetic stimulation in 20 healthy volunteers. Amplitude data revealed skewness of distribution and variance heterogeneity. Natural logarithmic transformation of amplitude data results in normal distribution and ensures variance homogeneity. There was a negative first-order autocorrelation between consecutive recordings, which indicates that a stimulus-free interval of 5 s in consecutive stimulations is insufficient to ensure independent events. In a variability study, no systematic changes in latency and amplitude during day-to-day examinations or in consecutive examinations were found. There was a significant change in latency data (p = 0.02) during a gradual increase of constant elements in the stimulation procedure, whereas the amplitude data were unchanged. Estimation of random contributors to the total variability in the magnetic stimulation technique was performed. Intersubject differences were the major contributor to the variability of latency data but not to variability of logarithmic amplitude data. The variance estimates of different examiners' contribution to the variability was 0.02 for latency data and 0 for amplitude data. This indicates that staff members familiar with the principles in magnetic stimulation and following a thorough verbal and written instruction in the standardized examination procedure can perform the stimulation procedure without increasing the data variability. 相似文献
734.
The present study reduced the levels of ovarian hormones to early postmenopausal levels by a GnRH agonist and evaluated the effects of a temporary suppression of ovarian hormones on premenopausal women's cardiovascular and neuroendocrine responses to laboratory challenges. The stress responses of 24 healthy young women were evaluated during three tasks during the early follicular phase and then after three monthly injections of Lupron, which suppressed their levels of estradiol, FSH, and LH. Thereafter, half the group resumed menstrual cycles (labeled Cycle), and half continued having Lupron injections in combination with transdermal estradiol (labeled Patch) and all were reevaluated a third time. A third group (labeled Control) of 12 women had four monthly injections of Lupron first and then were evaluated the first time. After their cycles resumed, they were reevaluated twice 3 months apart. Results showed that the magnitude of the blood pressure and catecholamine changes declined over the three evaluations, suggesting that the women's stress responses habituated. Although the suppression of ovarian hormone levels led to alterations in ovarian hormones for several months, which were accompanied by typical menopausal symptoms, cardiovascular and neuroendocrine responses to stress did not vary. This study did not test the effects of current estrogen exposure or of long term suppression of ovarian hormones upon cardiovascular and neuroendocrine responses. 相似文献
735.
736.
When chaperonins GroEL and GroES are incubated under functional conditions in the presence of ATP (5 mM) and K+ (150 mM), GroEL-GroES complexes appear in the incubation mixture, that are either asymmetric (1:1 GroEL:GroES oligomer ratio) or symmetric (1:2 GroEL:GroES oligomer ratio). The percentage of symmetric complexes present is directly related to the [ATP]/[ADP] ratio and to the K+ concentration. Kinetic analysis shows that there is a cycle of formation and disappearance of symmetric complexes. A correlation between the presence of symmetric complexes in the incubation mixture and its rhodanese folding activity suggests some active role of these complexes in the protein folding process. Accordingly, under functional conditions, symmetric complexes are found to contain denatured rhodanese. These data suggest that binding of substrate inside the GroEL cavity takes place before the symmetric complex is formed. 相似文献
737.
RP Adang AW Ambergen JL Talmon A Hasman JF Vismans RW Stockbrügger 《Canadian Metallurgical Quarterly》1996,57(2):118-134
The discriminative value of patient characteristics and dyspeptic symptoms for upper gastrointestinal endoscopic findings was prospectively assessed in 1,147 patients attending for their first diagnostic endoscopy and who answered paper (n = 431) or computerized (n = 716) questionnaires. The questionnaires provided detailed information concerning present dyspeptic symptoms, with special attention to provoking and/or relieving factors, and smoking and/or drinking habits. In logistic regression models each of a number of 'specific endoscopic diagnoses' was contrasted with normal endoscopy (n = 390), and 'relevant endoscopic disease' (oesophagitis, peptic ulcers, cancers; n = 269) was contrasted with 'irrelevant' and normal endoscopic findings (n = 878). From the regression model a receiver operating characteristic (ROC) curve could be constructed, and the area under the ROC curve (AUC) was calculated to summarize the discriminative power of the regression model. The best discrimination from patients with a normal endoscopy was achieved for patients with gastric (AUC = 0.86) or duodenal (AUC = 0.85) ulcers, followed by patients with hiatus hernia (AUC = 0.78 or oesophagitis (AUC = 0.77). The discriminative performance of the regression models was somewhat less for duodenitis/bulbitis (AUC = 0.75) and endoscopic gastritis (AUC = 0.73). In an open-access endoscopy unit setting, the value of preinvestigation history-taking for the prediction of clinically relevant endoscopic disease was very limited (AUC = 0.63). 相似文献
738.
The cytosolic nucleotide binding domains of cystic fibrosis transmembrane conductance regulator (NBD1 and NBD2) mediate ATP-dependent opening and closing of the Cl- channel pore. To learn more about NBD structure and function, we introduced a cysteine residue into the Walker A motif or the LSGGQ motif of each NBD and examined modification by N-ethylmaleimide (NEM). Covalent modification of either Walker A motif partially inhibited cystic fibrosis transmembrane conductance regulator channel activity, decreasing the open state probability by prolonging the long closed duration. An increase in cytosolic ATP concentration slowed the rate of modification. The data suggest that both NBDs interact with ATP to influence channel opening and that inhibition by NEM modification was in part due to decreased ATP binding. When cysteine was placed in the NBD2 Walker A motif, it was modified more rapidly than when it was placed in NBD1, suggesting that the NBDs are not structurally or functionally identical. Modification of a cysteine inserted in the LSGGQ motif of either NBD1 or NBD2 also inhibited channel activity. The rate of modification was comparable with that of a thiol in free solution, suggesting that the LSGGQ motif resides in a surface-exposed position in both NBDs. 相似文献
739.
740.
R Steffensen T Melchior J Bech H Nissen B Haastrup P Grande V Rasmussen JF Hansen K Skagen T Haghfelt 《Canadian Metallurgical Quarterly》1997,11(5):629-635
This study was designed to compare once-daily administration of 5-10 mg amlodipine with two daily doses of 40 mg sustained-release isosorbide dinitrate in 59 patients with stable angina using a randomized, double-blind, crossover study design. Anginal episodes, nitroglycerin consumption, and possible adverse events were recorded in a diary. A maximal symptom-limited bicycle exercise test and 48-hour ambulatory ECG monitoring were performed at baseline and at the end of each 5-week period of therapy. Exercise time, time to angina, time to ST depression, and maximal ST depression were measured during exercise. During ambulatory monitoring, the number of ischemic episodes and the duration per hour of ST depression were assessed. Amlodipine significantly reduced anginal episodes (P < 0.001) when compared with isosorbide dinitrate. Furthermore, amlodipine prolonged time to ST depression (P < 0.001) and time to angina (P < 0.05) when compared with isosorbide dinitrate. The number and duration of ischemic episodes during ambulatory monitoring were significantly reduced with amlodipine when compared with baseline values (P < 0.05), whereas no differences were found between isosorbide dinitrate and baseline. Adverse events were reported more frequently with isosorbide dinitrate than with amlodipine (P < 0.02). Amlodipine appears to be more effective and tolerable than sustained-release isosorbide dinitrate as monotherapy for chronic stable angina. 相似文献