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61.
Haemophilus influenzae is a bacterium of medical interest of which the entire genome has been sequenced. The proteome of the microorganism has been analyzed by two-dimensional gel electrophoresis, during which immobilized pH 3-10 gradient strips were used and approximately 300 proteins were identified. In order to detect additional, basic proteins, we analyzed the soluble protein fraction of H. influenzae and the proteins of fractions collected from affinity chromatography on heparin, by two-dimensional gel electrophoresis, using for the first-dimensional separation immobilized pH gradient strips comprising the pH region of 6-11. The protein spots were analyzed by matrix-assisted laser desorption ionization-mass spectrometry. One hundred and two proteins were identified, of which 58 were identified for the first time. A large percentage of the basic proteins represent nucleic acid binding and, in particular, ribosomal proteins. The locations of the identified basic proteins of H. influenzae are indicated in a two-dimensional map. 相似文献
62.
RM Mu?oz LA Pulpón M Yebra J Segovia M San Martín C Salas 《Canadian Metallurgical Quarterly》1998,17(11):801-806
The fibrinolytic capacity of patients with acute myocardial infarction (AMI) is known to be impaired. The primary regulatory element of the fibrinolytic system is plasminogen activator inhibitor (PAI). It has been previously observed that there are 2 peaks in the plasma PAI level of AMI patients at 4h and 16h after thrombolytic therapy with recombinant tissue plasminogen activator (rtPA). Lanoteplase/SUN9216 is a mutant tPA with a biological half-life longer than that of rtPA. Thrombolytic therapy with mutant tPA or rtPA was carried out consecutively in 21 patients with AMI (8 patients as the mutant tPA group, and 13 patients as the rtPA group). The recanalization time of the mutant tPA group was significantly faster than that of the rtPA group (16.1 +/- 3.9 min vs 39.6 +/- 4.8 min, p<0.01). The PAI activity at 4h after the initiation of thrombolysis was significantly lower in the mutant tPA group than in the rtPA group (8.74 +/- 5.46IU/L vs 26.74 +/- 3.35 IU/L, p<0.01). There was a one mild peak in serial plasma PAI activity levels 24h after the initiation of thrombolysis. The results suggest that thrombolytic therapy with mutant tPA reduced the impairment of fibrinolytic capacity. The mutant tPA gives faster recanalization and lower PAI activity after successful thrombolysis, compared with rtPA. 相似文献
63.
A six-day-old Missouri foxtrotter colt was examined because it had had diarrhoea since it was 24 hours old. A diagnosis of colitis, septicaemia, and disruption of the arterial blood flow to the pelvic limbs was made on the basis of clinical and laboratory findings. Despite intensive medical therapy, the foal died 13 hours after being examined. Postmortem examination revealed diffuse fibrinous enteritis with lymphoid necrosis, multifocal fibrinonecrotic typhlocolitis, disseminated intravascular coagulation, and a large occluding thrombus at the aortic termination. The results of bacteriological culturing supported the diagnosis of septicaemia leading to activation of the clotting cascade, disseminated intravascular coagulation, aorto-iliac thrombosis and infarction of the pelvic limbs. 相似文献
64.
The 12 isomers of monoammine chromium(III) ATP have been used to probe the ATP binding sites of yeast 3-phosphoglycerate kinase and glycerol kinase from Candida mycoderma. Inhibition studies of 3-phosphoglycerate kinase show a dramatic decrease in isomer binding only when the ammonia is in the Delta axial facial anti position. This suggests an open site architecture with only one strong contact point between the coordination sphere and the enzyme surface. These results agree well with the computer modeling studies of bidentate chromium ATP into the nucleotide site determined by X-ray crystallography [McPhillips, T., et al. (1996) Biochemistry 35, 4118-4127]. Both methods describe an open site strongly supporting the validity of the inhibition studies. Inhibition studies of glycerol kinase show significant decreases in binding for all the tested ammonia positions, suggesting a closed site architecture with many contacts between the coordination sphere and the surface of the enzyme. This is in good agreement with X-ray studies [Hurley, T., et al. (1993) Science 259, 673-677] on the Escherichia coli glycerol kinase. Inhibition studies of hexokinase previously reported [Rawlings, J., et al. (1993) Biochemistry 32, 11204-11210] more closely resemble those of 3-phosphoglycerate kinase, suggesting the surprising result that however closely hexokinase and glycerol kinase are related structurally the site around the coordination sphere in hexokinase is functionally open like that of 3-phosphoglycerate kinase. 相似文献
65.
Immunological mimicry between host and microbial proteins has been suggested as a potential mechanism in the development of uveitis in humans. In this study immunological crossreactivity between anti-streptococcal monoclonal antibodies (MAbs) and the human eye was investigated. In indirect immunofluorescence, we demonstrated novel immunological crossreactivity of two anti-streptococcal MAbs (27 and 112) with the rod outer (and inner) segments of the retina of the human eye. In further studies, retinal S-Ag, a uveitogenic protein in the rod outer (and inner) segments, was found to react with the anti-streptococcal MAbs. In addition, several uveitogenic peptides of S-Ag were recognized by the anti-streptococcal MAbs. In the ELISA and Western immunoblot, anti-S-Ag MAbs crossreacted with group A streptococci and the streptococcal M protein further demonstrating sites of antigenic similarity. Homology between the retinal S-Ag and streptococcal M protein was observed in amino acid sequences repeated in the B repeat region of the streptococcal M5 protein. These data show that retinal S-antigen has immunological similarities with streptococcal M protein, a major virulence determinant and strong bacterial cell surface antigen. 相似文献
66.
67.
Data from all 225 women operated on for ectopic pregnancy in 1992-1994 at Sahlgrenska University Hospital were collected and compared with three previous cross-sectional investigations from our hospital (1975-1979, 1981-1982 and 1986-1987) in order to evaluate the extent to which surgical treatment and post-operative complications have changed over a 20 year period. Laparoscopic surgery, which was not possible in the 1970s, was used in almost 85% of the ectopic pregnancies in 1992-1994. Conservative treatment was still the most frequently used technique. The complication rate was 1.2% in 1975-1979 when only laparotomies were carried out. After the introduction of laparoscopic surgery (1986-1987), the complication rate rose significantly (7.3%) and continued to increase even when this procedure was established as routine (14.2% in 1992-1994). Post-operative complications were most frequent after conservative laparoscopic surgery (24.4%) while there were no complications after laparotomies. In spite of increasing complication rates the frequency of patients in pre-shock, as well as the proportion of patients with heavy intra-abdominal bleeding and tubal rupture, decreased over time. 相似文献
68.
The purpose of this study was to determine how well men recall reproductive information. By using a questionnaire, the authors surveyed men who had undergone orchiopexy for undescended testes and a group of matched control men, all of whom had had surgery at the Children's Hospital of Pittsburgh in Pittsburgh, Pennsylvania (n = 77), and their spouses. Subjects were a random subset of a larger (n = 1,212) male fertility study, which has been ongoing since 1992. In 1994, the spouses of men who participated in the study completed a short telephone survey that contained questions previously asked of their partners. Pearson correlations and kappa statistics were calculated to evaluate the accuracy of male recall of reproductive information. For the continuous measures, such as time to conception and frequency of intercourse, the correlations were high to moderate (r = 0.84 (p < 0.001) and r = 0.45 (p < 0.001), respectively). Agreement between the men and their spouses on the majority of bivariate (yes/no) questions, such as those concerning the use of birth control, as measured by the kappa statistic, was moderate to very good (K ranged from 0.14 to 0.69). Statistics were similar for formerly cryptorchid and control men. Male participants' responses to questions about their reproductive histories were accurate as compared with the responses given by their spouses. In this sample from a large cohort study, men appeared to recall reproductive information with acceptable accuracy. 相似文献
69.
70.
P Hanutsaha DR Guyer LA Yannuzzi A Naing JS Slakter JS Sorenson RF Spaide KB Freund M Feinsod DA Orlock 《Canadian Metallurgical Quarterly》1998,105(9):1632-1636
OBJECTIVE: Recent studies have shown that indocyanine-green videoangiography (ICG-V) is useful to image occult choroidal neovascularization. The authors studied the ICG-V findings in fellow drusen eyes of patients with unilateral exudative age-related macular degeneration (AMD). The authors also studied the occurrence of exudative changes to determine whether ICG-V is useful in predicting future exudative changes in these eyes with only drusen. DESIGN: Cohort study. PARTICIPANTS: The authors studied 432 consecutive patients diagnosed with unilateral exudative AMD in whom the fellow eye had only drusen by clinical fundus examination and fluorescein angiography. All of these eyes had ICG-V performed. Follow-up data were obtained in all eyes with abnormal indocyanine-green (ICG) angiograms and randomly sampled ICG angiograms of normal eyes. MAIN OUTCOME MEASURES: The initial ICG findings were classified as showing normal or abnormal hyperfluorescence. Abnormal hyperfluorescence eyes were subdivided into focal spots (focal areas of hyperfluorescence < 1 disc area in size) and plaques (areas of hyperfluorescence > 1 disc area). The development of exudative changes in eyes with normal and abnormal hyperfluorescence was compared. RESULTS: Of the 432 fellow eyes, 386 (89%) eyes with drusen had a normal ICG-V study, whereas 46 (10 focal spots and 36 plaques) (11%) eyes had an abnormal ICG-V. Exudative changes occurred in 6 (10%) of 58 normal ICG eyes and 9 (24%) of 38 eyes with abnormal ICG findings during a mean follow-up period of 21.7 months. The difference between drusen eyes with normal ICG angiograms and those with plaques on ICG-V regarding future exudative changes (10% vs. 27%, respectively) was statistically significant (P = 0.038). CONCLUSIONS: Abnormal ICG findings were found in 11% of eyes with clinically and fluorescein angiographically nonsuspicious drusen. The subgroup of patients with plaques on ICG-V had a higher chance of having exudative changes develop. Indocyanine-green videoangiography may be a predictive indicator of future exudative changes in eyes with drusen. A much larger prospective study seems justified. 相似文献