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11.
AIM OF STUDY: Evaluation by transesophageal echocardiography of the effect on the characteristics of physiological regurgitant jets (JF) resulting from prosthetic disfunction due to pathologic regurgitation (JF). PATIENTS AND METHODS: We studied 69 consecutive patients with the diagnosis of prosthesis in mitral position using transesophageal echocardiography and color doppler codification. The patients were divided in two groups (N and D groups) according to the presence of prosthesis disfunction by pathologic regurgitation. In each patient we determined planimetric areas and atrial peak depth of each JF and also the sum of JF planimetric areas of each mitral prosthesis. When pathological regurgitation was present we calculated the highest planimetric area, severity degree and atrial peak depth in each JP. RESULTS: The planimetric area in each JF of group N was 330 +/- 167 mm2 and in group D 117 +/- 116 mm2 (p less than 0.001). The sum of the areas of JF in group N was 474 +/- 204 mm2 and in group D 254 +/- 176 mm2 (p less than 0.01). The atrial depth of JF in group was 32 +/- 15 mm and in group D 26 +/- 18 mm (p less than 0.01). In group D 29% of the patients had mild pathological regurgitation, 10% moderate and 61% severe. The maximum planimetric area of JP in group D was 1078 +/- 1007 mm2 with atrial depth of 37 +/- 28 mm. CONCLUSION: The pathological regurgitation in disfunction prosthesis in mitral position has a significant reduction effect in the dimension of prosthesis physiologic regurgitation jets. This transesophageal echocardiographic observation makes it possible to characterize and clarify more precisely the different types of mitral prosthesis jets.  相似文献   
12.
A 34-years-old floor-layer developed optic neuropathy and motor neuron disease after being accidentally exposed to a solvent mixture containing methanol and other substances. Optic neuropathy is a complication of methanol poisoning, but the onset of a motor neuron disorder resembling amyotrophic lateral sclerosis after the exposure to these substances has not been previously described. The temporal onset of the clinical symptoms, biological plausibility, young age of the patient and absence of neurological disorders in the family history raises suspicion of a possible causative relationship.  相似文献   
13.
INTRODUCTION: The management of children receiving small bowel grafts involves potentially life-threatening complications that affect their nutritional status. The aim of this paper was to define these factors and their influence on nutritional outcome. PATIENTS AND METHODS: Patients with intestinal failure (IF) who received an isolated small bowel transplantation (SBT) or small bowel/liver transplantation (SBLT) at our hospital during the last 6 years were reviewed for weight Z-score, biochemical nutritional parameters, total parenteral nutrition (TPN) weaning, catheter-related sepsis, rejection and steroid treatment. RESULTS: Twenty patients, 11 females and 9 males, received a SBT or a SBLT and survived the postoperative period; in the present study we only included 11 children with follow-up periods longer than 1 year. Seven males and 4 females with a mean age of 4.5 years (range, 1 to 20 years) received 6 SBLT and 5 SBT. Nine (82%) were weaned from TPN to an amino-acid or peptide enteral formula during the first 6 months after surgery. During the first year there was a significant increase in total protein from 5.11 +/- 1.8 mg/dl to 6.1 +/- 1.5 mg/dl (p < 0.05) and an increase in albumin from 3.8 +/- 0.9 mg/dl to 4.5 +/- 1.1 mg/dl (p < 0.05). There was an increase in weight Z-score in 9 patients (82%) during the first year. Mean Z-score improved from - 2.6 +/- 1 at transplant to - 1.0 +/- 0.6 (p < 0.05) after 1 year. Three patients (27.2%) had at least one rejection period, which was treated with steroids alone or in combination. Mean weight Z-score 1 year after surgery was - 0.9 +/- 0.6 for patients without rejection and - 1.24 +/- 0.8 for those with at least one rejection episode treated with steroids (p > 0.1). Four patients (36%) had at least one catheter-related sepsis episode. Mean weight Z-score 1 year after surgery was - 1.01 +/- 0.6 for patients without catheter-related sepsis and - 1.24 +/- 0.8 for those with at least one catheter-related sepsis episode (p > 0.1). CONCLUSIONS: There was a significant improvement in weight Z-score and biochemical nutritional parameters 1 year after receiving a small bowel graft. No influence of steroids or catheter-related sepsis on children's nutritional status was noted 1 year after surgery, although this point will need further evaluation.  相似文献   
14.
Insulin was found to provoke rapid increases in diacylglycerol (DAG) content and [3H]glycerol incorporation into DAG and other lipids during incubations of rat hemidiaphragms and soleus muscles. Insulin also rapidly increased phosphatidic acid and total glycerolipid labeling by [3H]glycerol, suggesting that insulin increases DAG production at least partly through stimulation of the de novo pathway. Increased DAG production may activate protein kinase C (PKC) as reported previously in the rat diaphragm. We also observed apparent insulin-induced translocation of PKC from cytosol to membrane in the rat soleus muscle. The importance of insulin-induced increases in DAG-PKC signaling in the stimulation of glucose transport in rat diaphragm and soleus muscles was suggested by 1) PKC activators phorbol esters and phospholipase C stimulation of [3H]-2-deoxyglucose (DOG) uptake and 2) PKC inhibitors staurosporine and polymixin B inhibition of insulin effects on [3H]-2-DOG uptake. Although phorbol ester was much less effective than insulin in the diaphragm, phospholipase C provoked increases in [3H]-2-DOG uptake that equaled or exceeded those of insulin. In the soleus muscle, phorbol ester, like phospholipase C, was only slightly but not significantly less effective than insulin. Similar variability in effectiveness of phorbol ester has also been noted previously in rat adipocytes (weak) and BC3H1 myocytes (strong), whereas DAG, added exogenously or generated by phospholipase C treatment, stimulates glucose transport to a degree that is quantitatively more comparable to that of insulin in each of the four tissues. Differences in effectiveness of phorbol ester and DAG could not be readily explained by postulating that the latter acts independently of PKC, because DAG provoked the apparent translocation of the enzyme from cytosol to membranes in rat adipocytes, and effects of DAG on [3H]-2-DOG uptake were blocked by inhibitors of PKC in both rat adipocytes and BC3H1 myocytes. Collectively, our findings provide further support for the hypothesis that insulin increases DAG production and PKC activity, and these processes are important in the stimulation of glucose transport in rat skeletal muscle and other tissues.  相似文献   
15.
Eighty-seven different mineral waters available for purchase in the Federal Republic of Germany were tested for the presence of heterotrophic bacteria and, specifically, antibiotic-resistant Pseudomonas species. Waters lacking carbon dioxide and Heilwasser (waters often prescribed for a variety of ailments) tended to show the highest numbers of bacteria. Eighty-one isolates of Pseudomonas were obtained from 39 samples of mineral water. Of the 9 species found, P. cepacia and P. maltophilia, most commonly associated with nosocomial infections, made up 13. 6% of the isolates. These 2 species also showed the highest resistance to the ten antibiotics used in the study. A comparison of antibiotic resistance patterns between mineral water and clinical isolates from the Medizinische Hochschule, Hannover, shows a higher similarity than that between mineral water and Massachusetts General Hospital (Boston) isolates. With the exception of P. pseudoalcaligenes, all mineral water isolates showed basically 100% resistance to cefoxitin and were highly resistant to ampicillin. Only 1 of 81 isolates (1. 2%) was resistant to tobramycin, although 2 isolates of P. cepacia showed intermediate resistance to this drug. Though no P. aeruginosa were found in any of the samples, the presence of species associated with nosocomial infections and highly resistant to commonly used antibiotics suggests that careful thought be given to the routine ingestion of mineral water by compromised individuals and those with underlying disease.  相似文献   
16.
The role of glutamate in conditioned taste aversion was investigated. Both, in the amygdala (AMYG) and in the lateral hypothalamus (LH) extracellular levels of glutamate were assessed by microdialysis and capillary electrophoresis with laser induced fluorescence detection. Rats were conditioned by pairing a novel flavor (strawberry flavor) with an intraperitoneal injection of lithium chloride. When the conditioned stimulus (strawberry flavored solution) was injected into the mouth of conditioned rats, there was an increase of glutamate release in the AMYG, and a decrease in glutamate release in the LH. These results predicted that glutamate release in the AMYG and the LH was involved in CTA. This possibility was tested by MK-801 (glutamate antagonist) and glutamate microinjections. MK-801 injections in AMYG attenuated the rejection of the novel flavor, and in the LH did not cause any effect on CTA. Glutamate microinjections in the AMYG caused CTA. These results suggest that glutamatergic activity in the AMYG might be a relevant neurochemical correlate and cause of conditioned taste aversion.  相似文献   
17.
OBJECTIVE   Genetic analysis is now essential for the accurate screening of families with multiple endocrine neoplasia type 2 (MEN2). We present the genetic analyses by both haplotype and direct RET proto-oncogene mutation analysis in seven Mediterranean MEN 2A families and have compared these results with biochemical screening tests and pathological examinations.
DESIGN  Total DNA was extracted from leucocytes. Linkage analysis was performed using five RFLP systems from three loci that flank the MEN2A locus (FNRB, RBP3, D10S15). RET proto-oncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Screening for medullary thyroid carcinoma or C-cell hyperplasia was performed by the pentagastrin provocation test. Adrenal medullary function was assessed by measurements of 24-hour urinary excretion of catecholamines and their metabolites. Serum calcium and phosphate measurements were the initial screen for hyperparathyroidism. Serum PTH was determined only if hyperparathyroidism was suggested by the former determinations.
PATIENT   Genetic study was performed in 59 individuals (39 at risk) from seven kindreds of Mediterranean origin with MEN 2A.
RESULTS   Diagnosis by linkage analysis was not possible in 30% of individuals at risk, but RET proto-oncogene analysis identified all these individuals. Mutations of the RET proto-oncogene were detected in exon 10 (codon 618) in one MEN 2A kindred and in exon 11 (codon 634) in the others. The results of direct analysis were concordant with linkage studies in each case. Three individuals from different MEN 2A kindreds, who were subsequently shown not to be gene carriers, had false positive pentagastrin stimulation tests.
CONCLUSION   Biochemical tests can be replaced by direct DNA mutation analysis as the first line screening test in order to identify gene carriers of MEN 2A.  相似文献   
18.
A comparative statistical analysis of "synaptic ribbons" evolution over a 24 hour period during two different photoluminous seasons (September, and winter) is carried out. Seventy male rats were used. Statistical analysis involved the Kolmogorov-Smirnov test, variance analysis, the Student t-test and Pearson's correlation test. The results show that "synaptic ribbons" evolve during the circadian phase and through two different seasons, with a clear and marked influence of point-time (p < 0.0001) and season (p < 0.0001).  相似文献   
19.
2,4,5-trimethylthiazoline (TMT) is a volatile component of the anal gland secretion of the red fox and elicits behavioral and physiological fear responses in the rat. Using instrumental conditioning paradigms, we determined olfactory detection thresholds for TMT in three rats, a natural prey species of the red fox, and compared their performance to that of three squirrel monkeys, three spider monkeys and four pigtail macaques, all non-prey species of the red fox. We found that the rats were able to discriminate concentrations between 0.04 and 0.10 ppt (parts per trillion) of TMT from the odorless solvent which is by far the lowest olfactory detection threshold for an odorant reported in rats so far. In contrast, the spider monkeys needed 0.14-1.38 ppb (parts per billion), the pigtail macaques 0.41-4.07 ppb, and the squirrel monkeys 4.07-13.80 ppb to detect TMT which does not rank among the lowest olfactory thresholds reported for these three primate species. Thus, these results support the assumption that the behavioral relevance of an odorant may be an important determinant of a species' olfactory sensitivity.  相似文献   
20.
A nutritionally variant Streptococcus pyogenes strain was isolated from a periorbital abscess. The organism was identified with the use of three rapid biochemical test kits, and the group A antigen was detected by conventional serology as well as direct antigen detection tests.  相似文献   
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