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31.
P. Schuck V. Briard S. M jean M. Piot MH. Famelart JL. Maubois 《Drying Technology》1999,17(7):1347-1357
A drying method by desorption in a water activity meter was used to simulate the conditions of spray drying and to determine the water transfer inside dairy concentrates towards the surface and from the surface to the drying air. The concentrates were also spray dried and solubility index of powders were determined during reconstitution. Whey protein concentrates (WPC) and native phosphocaseinate suspensions (NPCS) were used to study the effect of NaCl (420 mM), CaCl2 (222 raM), sodium phosphate (173 mM) and sodium citrate (238 mM) on the water transfers. The decrease in water transfer during drying was explained by the high hygroscopicity of added mineral salts to WPC. NaCl addition to NPCS decreased the water transfer during drying, but increased the solubility index. Citrate and phosphate addition to NPCS increased the water transfer during drying and reconstitution. CaCl2 increased the water transfer during drying but the solubility index was always low. Results are discussed as a function of the aqueous environment, of the nature of mineral salts, of the structure of dairy proteins and of protein solvation. 相似文献
32.
Dextropropoxyphene hydrochloride increases significantly oxygen uptake in whole rat brain homogenates at concentrations of 10(-4), 10(-5), 10(-6) M when using sucrose 0.25 M pH 7.4 as incubation medium. If substrate and cofactors are added to the sucrose, this drug decreases oxygen uptake at 10(-3) M concentration in brain and liver rat homogenates, and it also decreases significantly the P:O quotient of mitochondria in both organs by uncoupling the oxidative phosphorylation. 相似文献
33.
In 13 patients with systemic lupus erythematosus, globulin fractions of sera from serial bleedings were assayed for the induction of serotonin release from normal platelets. Releasing activity appeared at some time in the sera of seven patients, five of whom had episodes of thrombocytopenia. Conversely, only one patient manifested thrombocytopenia without the occurrence of serotonin releasing activity at any time. In three patients with episodes of thrombocytopenia, increases in serotonin releasing activity temporally coincided with drops in platelet count. These data show that levels of circulating platelet serotonin releasing factor(s) vary in the course of systemic lupus erythematosus and these variations may be inversely related to the platelet count in particular patients. 相似文献
34.
The treatment of high blood pressure at the general medical clinic of a traditionally oriented university hospital was found to be unsatisfactory for most patients. Charts of all hypertensive patients (diastolic blood pressure, greater than or equal to 105 mm Hg) who made their first clinic visit in 1964 or 1971 were reviewed. Half of all patients were lost to follow-up within the first year, and blood pressure control was achieved by only one third of the patients. New information contained in the Veterans Administration study reports (1967 and 1970) had no effect on workup, compliance, or blood pressure decline. Furthermore, no significant relationship was found between blood pressure reduction and medical process, therapeutic regimens, or patient compliance. These data suggest that, in contrast to experience obtained in programs specifically designed for long-term management of this chronic disease, the present-day general medical clinic cannot satisfy the needs of most hypertensive patients. 相似文献
35.
1. The characteristics of absorption of individual amino acids from amino acid mixtures simulating casein and from enzymic hydrolysates of casein containing oligopeptides as well as free amino acids are known to be different. The differences, which are attributable to mucosal uptake of small peptides, involve more rapid absorption from the enzymic hydrolysates of certain amino acids which are relatively slowly absorbed from the amino acid mixtures. This could lead to more effective utilization of amino acids from the enzymic hydrolysates than from the amino acid mixtures. 2. To obtain further information bearing on this hypothesis, we have used a recently developed technique for portal cannulation in the guinea pig to make a preliminary investigation of amino acid concentrations in the portal venous plasma at intervals after the infusion into the duodenum of equivalent amounts of (a) an amino acid mixture simulating casein and (b) a partial enzymic (papain followed by kidney peptidases) hydrolysate of casein, the two preparations being infused in separate experiments. 3. For some amino acids, such as leucine, isoleucine, valine, phenylalanine and lysine, the curves after the enzymic hydrolysate were fairly similar to the corresponding curves after the amino acid mixture, though usually slightly lower. With other amino acids, the curves after the enzymic hydrolysate were very much lower than the corresponding curves after the amino acid mixture. With serine, glutamine, proline and glycine this discrepancy was particularly great. 4. The results cannot yet be fully explained, but their main features are explicable by the hypothesis that the lower amino acid concentrations in portal plasma after the enzymic hydrolysate are the result of entry of amino acids into the portal blood in peptide form, in which they would not be detectable by the analytical technique employed, and possibly also of more rapid clearance of amino acids from the blood during absorption of this preparation. 相似文献
36.
Cyclofenil is a new diphenyl ethylene derivative related to stilboestrol without oestrogenicity but with marked effects on connective tissue metabolism. The drug has been tested, in a daily dose of 200mg X3, in six patients with progressive systemic sclerosis (PSS) to analyze the expected beneficial effects on the PSS symptoms. The typical skin hardness, joint and muscle rigidity, and reduced breathing capacity were improved to varying dgrees. The only side-effect was a slight transient liver enzyme elevation in 1 out of 6 patients. A slight increase was found in urinary calcium and hydroxyproline excretion. In several cases serum calcium, cholesterol, triglyceride and in some cases the serum uric acid levels were decreased. The ANF titres diminished to varying degrees in 4 out of 6 patients. These results indicate that further detailed clinical and laboratory studies on the therapeutic potential of cyclofenil in PSS and other diseases affecting connective tissue seen to be justified. 相似文献
37.
The effects of zinc and copper salts on the survival of the two species of freshwater fish, common carp, Cyprinus carpio, and grass carp, Ctenopharyngodon idellus, were investigated. It was discovered that the levels of tolerance to the concentration of the metals were species-specific. Cyprinus carpio was found to be more susceptible to copper, whereas Ctenopharyngodon idellus was more susceptible to zinc. In general, copper was more toxic than zinc, as revealed by the survival times. The body and the gills of dead fish seemed to be covered by a veil-like film which looked like coagulated mucus and which was formed by the heavy-metal ions reacting with some constituents of the mucus and which was formed by the heavy-metal ions reacting with some constituents of the mucus secreted by the gill. The histopathological assessment of the gill and liver of Cyprinus carpio was also carried out. Particles were observed around the gills of the dead fish treated with zinc and copper salts, although no other major changes were found in the gill. Several histopathological changes were observed in the livers, including the presence of particles. The symptoms of the liver suggested that the internal injury was also an important feature of the intoxicants. 相似文献
38.
MH Safir AE Gousse ES Rovner DA Ginsberg S Raz 《Canadian Metallurgical Quarterly》1999,161(2):587-594
PURPOSE: The 4-defect repair of grade 4 cystocele corrects discrete and severe deficiencies of vesicourethral support. We describe this technique used during pelvic reconstruction in 130 women. MATERIALS AND METHODS: During a 3-year period 130 patients (age range 35 to 96 years) underwent repair of grade 4 cystocele using the 4-defect repair technique. Cystocele repair had been performed in 60 patients (46%) and hysterectomy had been performed in 85 (65%). A "goalpost incision" is used in the vaginal wall to facilitate separation of the wall from underlying perivesical fascia, entry into the retropubic space, and exposure of the urethropelvic ligament, cardinal ligament and perivesical fascia. The 4 polypropylene sutures are used to provide an anterior vaginal wall sling which is modified to incorporate perivesical fascia and cardinal ligaments. Central defect repair is achieved by approximation of the cardinal ligaments and midline plication of the perivesical fascia over absorbable mesh. RESULTS: A total of 112 patients were available for followup which ranged from 6 to 42 months (mean 21). Repair of grade 4 cystocele was accompanied by other transvaginal repairs in 94 patients (83%), including rectocele repair in 81, hysterectomy in 22 and enterocele repair in 31. Of the patients 92% had excellent objective and subjective results for anatomical cystocele repair. Of the patients with preoperative stress urinary incontinence 90% had excellent or good subjective results. De novo urge incontinence was seen in 7% of patients. CONCLUSIONS: The 4-defect repair technique relies on anatomical restoration of 4 distinct deficiencies of pelvic support and is highly effective for relief of symptoms of grade 4 cystocele. 相似文献
39.
40.
Colonization of the nasopharynx by a middle ear pathogen is the first step in the development of otitis media in humans. The establishment of an animal model of nasopharyngeal colonization would therefore be of great utility in assessing the potential protective ability of candidate vaccine antigens (especially adhesins) against otitis media. A chinchilla nasopharyngeal colonization model for nontypeable Haemophilus influenzae (NTHI) was developed with antibiotic-resistant strains. This model does not require coinfection with a virus. There was no significant difference in the efficiency of NTHI colonization between adult (1- to 2-year-old) and young (2- to 3-month-old) animals. However, the incidence of middle ear infection following nasopharyngeal colonization was significantly higher in young animals (83 to 89%) than in adult chinchillas (10 to 30%). Chinchillas that had recovered either from a previous middle ear infection caused by NTHI or from an infection by intranasal inoculation with NTHI were completely protected against nasopharyngeal colonization with a homologous strain and were found to be the best positive controls in protection studies. Systemic immunization of chinchillas with inactivated whole-cell preparations significantly protected animals not only against homologous NTHI colonization but also partially against heterologous NTHI infection. In all protected animals, significant serum anti-P6 and anti-HMW antibody responses were observed. The outer membrane P6 and high-molecular-weight (HMW) proteins appear to be promising candidate vaccine antigens to prevent nasopharyngeal colonization and middle ear infection caused by NTHI. 相似文献