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1.
The cytopathogenic action of P. mallei on macrophages of golden hamsters and transplantable Hep-2 cell culture was studied. It was shown that the culture test systems may be efficient in estimation of the P. mallei virulent properties. The effect of antibacterial drugs on intracellular P. mallei was also studied.  相似文献   

2.
Lymphocytic gastritis is a recently described gastric inflammation, characterized by an increased intraepithelial lymphocytic infiltrate mainly composed of T-lymphocytes. Endoscopically it correlates mainly with diffuse varioliform gastritis. Ménétrier's disease is a hypertrophic gastropathy with enlarged gastric folds. The histological picture is that of foveolar hyperplasia and glandular cysts of the mucosa. A few small series of lymphocytic gastritis with microscopic and endoscopic features of Ménétrier's disease have been published previously. We describe a similar case associated with a gastric adenocarcinoma.  相似文献   

3.
Beta-lactamase production is one of the major mechanisms of resistance amongst bacteria especially the enteric bacilli. The purpose of this study is to assess the in-vitro activity of Sulperazon, a combination of cefoperazone and an irreversible beta-lactamase inhibitor, sulbactam, against the cefoperazone resistant isolates of aerobic gram-negative bacilli. A total of 92 such strains were tested. It was found that at a concentration of < or = 8 mg/l of sulbactam added to cefoperazone 82% of Klebsiella spp, 100% of E. coli, 100% of Enterobacter spp, 33% of Pseudomonas aeruginosa, 67% of Pseudomonas spp and 62% of Acinetobacter spp that were resistant to cefoperazone alone were susceptible to the combination. Hence it is concluded that the addition of sulbactam to cefoperazone does expand the spectrum of the in-vitro activity of cefoperazone.  相似文献   

4.
This study compared the ability of three types of engine driven instrumentation techniques to negotiate and prepare small, slightly curved root canals. Forty five mesial roots of extracted maxillary and mandibular first permanent molars were classified into three groups. Group (I) was prepared by Canal Leader system, group (II) was prepared by Nickel Titanium files and group (III) was prepared by Canal Master technique. Radiographs of the root canal space before and after preparation was carried out by the aid of an experimental model. Enlarged photographic prints obtained from radiographs were scored for shaping effectiveness of the three techniques in respect to canal course, position & width of apical constriction and lack of ledge formation. The results indicated that the Canal Leader system was an efficient technique in maintaining canal curvature, absence of zipping, transportation or ledge formation in almost all of the specimen tested, followed by the Nickel Titanium files and then the Canal Master technique which produced more straightening and destruction of apical constriction.  相似文献   

5.
6.
Diclofenac (0.5-2 mM) dose- and time-dependently reduces the viability of isolated hepatocytes. This effect cannot be counteracted by the calcium channel blockers diltiazem (0.05-0.1 mM) and verapamil (0.05-0.5 mM), the calmodulin antagonist calmidazolium (0.01 mM) or Quin 2-AM (0.1 mM), an intracellular calcium chelating agent. On the contrary, verapamil even accentuates the toxic effects of diclofenac. It is concluded from these results, that diclofenac causes cell damage by other mechanisms than calcium overload.  相似文献   

7.
Glycoprotein (GP)-specific platelet-associated IgG (PA-IgG) may be demonstrable in autoimmune-mediated thrombocytopenia. We studied 159 consecutive patients with histories of thrombocytopenia by a modified direct monoclonal antibody-specific immobilization of platelet antigens (direct MAIPA) assay, which immobilizes GP IIb/ IIIa, GP Ib/IX and GP Ia/IIa simultaneously. This modification requires smaller quantities of platelets than standard measurements performed separately. PA-IgG was present in 84/159 (53%) patients, as shown by the direct platelet immunofluorescence test (PIFT) with flow cytometry as a reference. PA-IgG against GP IIb/IIIa and/or GP Ib/IX and/or GP Ia/IIa was noted in 46 patients (29%), of whom 93% (43/46)-were also PA-IgG positive. The amount of PA-IgG detected by PIFT correlated directly with that detected by direct MAIPA (r = 0.71; P < 0.001). Only three patients 12548 with negative direct PIFT had GP-specific PA-IgG. GPV-specific PA-IgG was detected in 13 (10%) of the 125 patients, in whom further studies could be performed. In the subgroup of patients with GP-specific PA-IgG, the median fluorescence intensities of direct PIFT were higher than in patients with no GP-specific PA-IgG (P < 0.001). Direct PIFT and direct MAIPA divided the patients into asymmetric subgroups. However, the relative roles of these tests in the diagnosis of autoimmune-mediated thrombocytopenia await further studies.  相似文献   

8.
Preimplantation genetic diagnosis is currently used in clinical practice. In experienced hands the biopsy procedure alone does not affect the further in-vitro and in-vivo developmental potential of animal and human embryos. No data exist on the combination of cryopreservation of embryos at the pronuclear and/or 8-cell stage and/or biopsy at the 8-cell stage. Pronuclear stages of mouse F1 hybrids (C57Bl/jxCBA) were harvested and divided into several experimental groups. The developmental rates of zygotes, which were neither biopsied nor cryopreserved were used as data control. Others were only cryopreserved at the pronuclear stage (C-PN), or at the cleavage stage (C-CS), or both. Each of these groups was also combined with or without a biopsy. Only the hatched blastocyst rate (HBR), but not the 'simple' blastocyst rate, showed significant differences between groups. Neither C-PN (HBR = 60.42%), nor C-CS (63.16%), nor a combination of both (59.46%) had an impact on the hatched blastocyst rate when compared with that of the control group (67.46%). The biopsy procedure (55.93%) also proved not to be harmful for the embryos. The embryos, which were C-PN and C-CS, and subsequently biopsied, showed a significantly lower hatched blastocyst rate (39.62%) than that of the control, C-PN, C-CS, and C-PN/C-CS groups (P < 0.05). The combination of C-PN and cleavage-stage biopsy also lead to a lower hatched blastocyst rate (42.22%), compared with that of the control group (P < 0.05). It was concluded that couples must be advised that an effect on embryos which have undergone a combined cryopreservation and micromanipulation procedure cannot be ruled out. However, cryopreservation at the pronuclear or at the 8-cell stage alone, or in combination with a biopsy procedure, does not influence the further development of the embryo.  相似文献   

9.
The effect of thyroid hormones on lipoprotein(a) plasma concentrations and the other parameters of lipoprotein metabolism was studied in 158 patients with thyroid dysfunction and in 37 euthyroid controls (cross-sectional study). Multiple regression analysis revealed that 65.5% of the variability in lipoprotein(a) levels were predicted by changes in lipoprotein(a) phenotypes (60.5%), thyrotropin (3.5%), and age (0.8%). The lipid parameters, however, showed no significant effect on lipoprotein(a). A subgroup analysis on samples from patients with large lipoprotein(a) isoforms showed that 28% of the variability in lipoprotein(a) concentrations could be explained by changes in thyroid function (19.1%), age (6.5%) and triglycerides (3.5%). Much stronger correlations were found between thyrotropin and total cholesterol, low density lipoprotein cholesterol or apolipoprotein B respectively (R2=0.951 for low density lipoprotein cholesterol, R2=0.801 for apolipoprotein B). Our data suggest that thyroid hormone is a significant modulator of lipoprotein(a) metabolism. However, different mechanisms are responsible for the change in lipoprotein(a) levels and for the decrease in total- and low density lipoprotein cholesterol levels.  相似文献   

10.
11.
The authors analyze the possibility to reduce the number of reoperations of the thyroid gland, based on a group of thyroid operations performed at the Surgical Clinic of the Second Medical Faculty Charles University and Faculty Hospital Motol during the 22-year period from 1975-1997. 507 reoperations from a total number of 4501 thyroid operations amount to 11.3%. In the authors opinion correct indication of the operation is most important as well as the correct extent and technique of the primary operation. The achieved results are except for unilateral temporary lesions of the NLR comparable with primary operations.  相似文献   

12.
PURPOSE: To study the direct effect of heavy ions and electrons on thymidine. MATERIALS AND METHODS: The thymidine samples in the solid state were exposed to a beam of O7+ heavy ions with an energy of 10.6 MeV/u (LET approximately 500keV/microm) and to electrons of 2MeV (LET approximately 0.18keV/microm). The major decomposition products of thymidine were purified by high performance liquid chromatography (HPLC) and identified by extensive spectrometric measurements (UV, mass spectroscopy, 1H and 13C NMR). RESULTS: The main degradation products of thymidine were isolated and characterized. Reaction mechanisms, involving transient radical species, are proposed to explain the heavy ion-mediated formation of the modified products. Furthermore, a semi-quantitative comparison of the modifications induced within thymidine by the two types of radiations was performed. CONCLUSION: Several new radiation-induced thymidine decomposition products have been isolated and characterized. The comparison of the effects induced by heavy ions and electrons on thymidine in the solid state clearly indicates several significant differences in the mechanisms of action. A relative increase in the extent of the modifications of the sugar moiety with respect to those of the base is observed with the heavy ions by comparison with electrons.  相似文献   

13.
14.
The duck interrenal cell possesses ultrastructural characteristics common to other steroid-secreting cells. Lipid droplets and mitochondria are abundant and lie principally at the apical end of the cell. Lipid droplets are not membrane-limited. Cisternae of smooth endoplasmic reticulum that are occasionally continuous with the less abundant rough endoplasmic reticulum are a prominent feature of the interrenal cell. Tubular profiles of rough endoplasmic reticulum often lie tangentially to mitochondria and ribosomes are either free, grouped in polyribosomal clusters, or bound to the endoplasmic reticulum. Mitochondria possess tubular cristae in the inner regions of the gland and frequently contain a paracrystalline array of small 10nm (o.d.) tubules and less frequently a hexagonal array of 40 nm trilaminar rings. Other cytoplasmic components include dense bodies, residual bodies, microtubules, microfilaments and specialized single membrane-bound vesicles. Gap junctions, intermediate junctions and interdigitating processes constitute the main intercellular associations. No tight junctions were identified. The single membrane-bound vesicles which are occasionally filled with a low electron-dense, lipid-like material form septate-like "junctions" with the plasma membrane. The septa bridge an intracellular gap of 15-17 nm. The vesicles are usually located near the subendothelial space at the basal and basilateral regions of the cell. Occasionally, vesicles fuse with the plasma membrane. It is suggested that these vesicles represent morphological evidence for the exocytotic release of steroid hormones.  相似文献   

15.
A set of lectins with different carbohydrate specificities were used for a histochemical analysis of the duodenal glands of rats which had different food rations during 3 months. Lectin receptors in glandulocytes of the duodenum had different spectra under different food regimens: protein diets of the animals correlated with the accumulation of glycopolymers in the glandular epithelium with the terminal residues of N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, L-fucose, higher content of cellulose in food was followed by reduction of fucosoglycans in combination with accumulation of mannose-containing glycopolymers. The regular specific features found point to quantitative and qualitative changes to the formed secretion of the duodenal glands under the influence of changing conditions of nutrition.  相似文献   

16.
Continuous monitoring of dynamic changes of transcranial regional cerebral oxygenation (rSO2) was performed in 7 healthy volunteers (mean age 40.9 +/- 12.6 years; range 25-62 years) during normo- and hyperbaric oxygenation (HBO at 2.5 and at 1.95 ATA) using an INVOS 3100 cerebral oximeter. A significant change between HBO and control phase could be found in rSO2, alterations (p < 0.05; ANOVA, Tukey test). The results suggest that the calculation of rSO2 may be a useful method to monitor changes of oxygen saturation under hyperbaric conditions. However, the absolute quantification of rSO2 is useless at the moment and needs further investigation.  相似文献   

17.
30% of the student nurses promising to participate in an hypnosis study failed to keep the experimental appointment. When these pseudovolunteers are included with the volunteers, and compared with nonvolunteers, there are 2 significant differences of 38 comparisons of variables. When the pseudovolunteers are included with the non-volunteers, 8 comparisons, 1 of which was previously significant, are now significant. It is suggested that the definition of a volunteer may have bearing on the outcome of a study of volunteer personality or behavior, and that future study should utilize actual participation in an experiment as the definition. From Psyc Abstracts 36:05:5AF72L. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
The authors investigated the efficiency of the seromyotomy of the lesser curvature of the stomach in 11 dogs. Reduction of the acid production was verified by glass electrode pH measuring of the gastric mucosa. Scintigraphic examination showed that the operation did not damage the motor function (motility) of the stomach. The fact of peripheral vagotomy was established by histological examination: degeneration of nerve fibres was detected on the peripheral side of the line of the seromyotomy, vacuolar degeneration was found in the cells of parasympathetic ganglions, and amputation neurinomas were shown in the line of the seromyotomy.  相似文献   

19.
The pentagastrin stimulation test was given to ten brothers and sisters of two patients who had previously undergone total thyroidectomy for medullary carcinoma of the thyroid. 5 microng pentagastrin/kg body-weight were injected as an intravenous bolus and calcitonin levels determined before and after. The test was positive in four members of the family and the presence of a medullary carcinoma was subsequently confirmed in them histologically.  相似文献   

20.
Staphylococcus aureus produces and secretes a protein, Efb, that binds to fibrinogen, seems to be required for virulence, and may benefit the microorganism by delaying wound healing. Interactions of Efb with fibrinogen are influenced by divalent metal cations, including Ca2+. Increasing concentrations of Ca2+ increased the binding of fibrinogen to immobilized Efb, whereas binding of Efb to immobilized fibrinogen was decreased with increasing Ca2+ concentration. Studies with synthetic peptides showed that peptides from the carboxyl terminal half of Efb bound to soluble fibrinogen and enhanced the binding of fibrinogen to Efb. A peptide corresponding to a repeated sequence in the amino terminal half of the protein also bound fibrinogen and inhibited binding of fibrinogen to Efb. These results may provide clues to the biological function of Efb and aid in the rational design of agents to block the Efb fibrinogen interaction.  相似文献   

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