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1.
A case of an uncommon congenital primitive neuroectodermal cerebellar tumor (PNET) in a 5-month-old child is reported. After subtotal surgical resection, the residual tumor did not respond to radiation and chemotherapy. Histologically, the tumor was composed of small, round, undifferentiated cells and several other patterns like astrocytomatous, oligodendrogliomatous, and ependymomatous structures. Immunostaining was positive for most of the cells for vimentin and S 100, fewer were positive for glial fibrillary acid protein (GFAP) and neuron-specific enolase, and only a few for synaptophysin. Surprisingly, the tumor showed strong expression of several monoclonal cytokeratins (CK) with different molecular weights, together with epithelial membrane antigen. Furthermore, we found a coexpression of the tumor cells for CK and vimentin, while CK-GFAP and CK-S 100 were negative. Ultrastructurally, intracyto-plasmic intermediate filaments could be observed corresponding to immunohistochemical CK expression. The very strong CK and vimentin expression in this case was interpreted as a sign of the embryonic nature of the tumor. 相似文献
2.
In order to clarify the reported discrepancies in S100 alpha protein and mRNA distribution in rat tissues, a rat S100 alpha cDNA has been isolated and this species homologous probe along with a rat S100 beta cDNA probe has been used to examine S100 mRNA expression in rat tissues. Although the rat S100 alpha cDNA was missing approximately 30 nucleotides of coding sequence, only 4 conservative changes in amino acid sequence were observed when the deduced amino acid sequence was compared to the bovine S100 alpha amino acid sequence. Thus, S100 alpha proteins, like S100 beta proteins, are highly conserved among species. All nineteen of the tissues examined (including cerebrum and cerebellum) contained S100 alpha mRNA. In addition, S100 beta mRNA was detected in thirteen of the nineteen tissues examined. These results are in agreement with previous protein distribution studies and further demonstrate that S100 proteins are not brain-specific and are expressed in a large number of tissues. Although S100 alpha and S100 beta mRNAs were detected in rat tissues which had previously been reported to contain S100 alpha and S100 beta protein, a direct correlation between the protein and mRNA levels were not observed, suggesting that different mechanisms regulate S100 expression in various tissues. S100 alpha exhibited a single similar size mRNA species (0.5 Kb) in all tissues examined, as did S100 beta (1.5 Kb), suggesting that the individual S100 proteins are expressed as single mRNA and protein products in rat tissues. 相似文献
3.
L. Ostrosky-Zeichner C. Sable J. Sobel B. D. Alexander G. Donowitz V. Kan C. A. Kauffman D. Kett R. A. Larsen V. Morrison M. Nucci P. G. Pappas M. E. Bradley S. Major L. Zimmer D. Wallace W. E. Dismukes J. H. Rex 《European journal of clinical microbiology & infectious diseases》2007,26(4):271-276
The study presented here was performed in order to create a rule that identifies subjects at high risk for invasive candidiasis
in the intensive care setting. Retrospective review and statistical modelling were carried out on 2,890 patients who stayed
at least 4 days in nine hospitals in the USA and Brazil; the overall incidence of invasive candidiasis in this group was 3%
(88 cases). The best performing rule was as follows: Any systemic antibiotic (days 1–3) OR presence of a central venous catheter
(days 1–3) AND at least TWO of the following—total parenteral nutrition (days 1–3), any dialysis (days 1–3), any major surgery
(days −7–0), pancreatitis (days −7–0), any use of steroids (days −7–3), or use of other immunosuppressive agents (days −7–0).
The rate of invasive candidiasis among patients meeting the rule was 9.9%, capturing 34% of cases in the units, with the following
performance: relative risk 4.36, sensitivity 0.34, specificity 0.90, positive predictive value 0.01, and negative predictive
value 0.97. The rule may identify patients at high risk of invasive candidiasis.
Results of this project were partially presented at Focus on Fungal Infections 14, New Orleans, LA, USA, 2004. Abstract no.
51. 相似文献
4.
Puncture-cytological and histomorphological investigation results are presented in transplanted tumor Jensen sarcoma. The tested tumors did not respond to therapy in growth reaction and reached a quarter of the body mass of the experimental animals on day 18 post transplantation. Within the five groups (untreated, cisplatin daily 0.6 mg/kg b.w., irradiated with 2 Gy S. D., 20 Gy T. D. only, and 2 groups combined therapy cisplatin and irradiation) cytological differences were shown between the several therapeutic groups already at therapy day 7 in spite of similar growth reaction, but not between centre and periphery of tumors, that were marked more distinctly and confirmed in histomorphological picture at the end of therapy at day 18 p.t. The increased occurrence of giant cells with many nuclei and leukocytic inflammation reaction seem to be a typical picture for combined therapy. 相似文献
5.
Pawe? Reichert Roman Rutowski Krzysztof Zimmer Jerzy Gosk Krzysztof Bogdan Roman Wiacek 《Chirurgia narzadów ruchu i ortopedia polska》2007,72(3):175-179
Purpose of work was estimation of the results of treatment of pseudoarthrosis of the long bone with the method of decortication, with use of autogenic bone depends on kind of pseudoarthrosis and kind of osteosynthesis. In the years 1995-2005 56 patients were treated because of pseudoarthrosis of long bone in our Clinic. Pseudoarthrosis is classified according to Weber-Cech classification. In the methodology of clinical estimation and subjective estimation of the patient Stewart and Hundley and Anderson classification were used. Union was achieved in 51 cases. Time of bone union achievement was 5 months. The results of treatment are depends on morfology of pseudoartrosis and are independs of kind of osteosynthesis. 相似文献
6.
Functional and metabolic effects of ribose in combination with prazosin, verapamil and metoprolol in rats in vivo 总被引:2,自引:0,他引:2
Ribose improves the function of the rat heart in various pathological conditions through its effects on cardiac energy metabolism, while having no direct haemodynamic actions. We therefore studied its functional and metabolic effects in closed chest rats when given in combination with prazosin, verapamil or metoprolol, all of which have direct effects on the circulation. Ribose administration for 24 h at 200 mg.kg-1.h-1 did not affect heart function but increased the available pool of 5-phosphoribosyl-1-pyrophosphate in heart (four fold) and skeletal muscle (1.7-fold), as assessed by the incorporation of 14C-adenine into the adenine nucleotides. The utilisation of adenine for adenine nucleotide synthesis, expressed as the ratio of adenine nucleotide radioactivity to tissue extract radioactivity, was 70% in heart and 20% in skeletal muscle under control conditions, and 97% and 88% after 24 h of ribose administration. Ribose decreased the 14C-adenine incorporation into the adenine nucleotides in kidney, lungs and liver. After 24 h infusion of prazosin (100 micrograms.kg-1.h-1), heart rate and LVdP/dtmax were not changed, but LVSP (-20%), mean aortic pressure (-16%) and peripheral resistance (-40%) were decreased. Cardiac output was enhanced (+40%). Verapamil (2mg.kg-1.h-1) and metoprolol (2mg.kg-1.h-1) infused for 24 h decreased the pressure-rate and pressure-volume product of the left ventricle to the same extent (-40%). Verapamil had no influence on cardiac output, while metoprolol depressed it (-30%). Simultaneous administration of prazosin, verapamil or metoprolol with ribose did not affect the ribose induced increase in the myocardial 5-phosphoribosyl-1-pyrophosphate pool.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Studies of post-lesional reorganization of central nervous connections have shown that central nerve fibers respond to nearby denervation by sprouting and formation of new terminals. The connections in the central nervous system (CNS) are accordingly much more plastic than was thought for a long time. This has revived the interest in transplantation of central nervous tissue. In this study we present some historical data on CNS transplantation supplemented by recent results obtained in our laboratory. Pieces of hippocampal tissue from embryonic or early postnatal rats were transplanted to different parts of the brain of littermates or adult rats. About two-thirds of the transplants were recovered after survival times ranging from 4 d to 2 years, and their cytological organization and intrinsic connections were monitored by cell and fiber stains and histochemical methods (AChE staining and Timm sulphide silver method). Comparison with both a normal and a lesioned control material revealed that in most transplants the tissue had developed as it does when left in situ in the donor brain, but deprived of its major afferent connections. In several instances we found evidence of a major exchange of connections between the transplants and host brains. The conditions needed for this to occur appeared to involve growth stimulation of host brain fibers by transection (host to transplant) and denervation of host neuropil (transplant to host). In cases where these conditions are met, the use of transplants may have future implications in attempts to repair lesions in the central nervous systems. 相似文献
8.
Effect of estrogen on eustachian tube performance 总被引:1,自引:0,他引:1
D Nir A Weissman A Drugan E Z Zimmer J Danino R Shenhav Z H Joachims 《The American journal of otology》1991,12(2):119-121
Changing levels of sex hormones have been previously associated with clinical symptoms due to alterations of the respiratory mucosa. Aural manifestations, however, have not yet been studied in this regard. Eustachian tube swallow test and blood levels of estrogen were evaluated daily in 25 women undergoing induction of ovulation. Most women showed a near stable eustachian tube performance over a wide range of estrogen levels, particularly in the physiologic range. However, there is a moderate decrease in eustachian tube function with increasing estrogen levels in some women, manifested mainly at levels beyond that of the normal menstrual cycle. 相似文献
9.
Transvaginal ultrasound measurements of the fetal heart at 11 to 17 weeks of gestation. 总被引:2,自引:0,他引:2
The scope of this article is to report on transvaginal ultrasound measurements of the fetal heart, which were performed in 124 healthy fetuses at 11 to 17 weeks of gestation. Normative growth charts were constructed. Statistical analysis demonstrated linear correlation (y = a + bx) between gestational age and measurements of the right and left ventricles. The ratio between fetal heart and the transverse diameter of the chest was found to be nearly constant at these gestational ages. 相似文献
10.
This study shows that arterial smooth muscle cells (SMC) isolated from rats receiving atherogenic doses of the lipid emulsion, Lipofundin-S, alter their in vitro growth properties. Compared to cells from control animals, SMC isolated from Lipofundin-S-infused rats show a reduction in both saturation density and response to increasing serum concentrations, without a change in the baseline proliferation. Also, SMC isolated from lipid-treated animals and grown for five days in the presence of 30, 150, or 300 pg/ml estradiol show a 30% increase in growth vs. cells from controls. Epinephrine at 1 microM stimulates growth in SMC from control rats, while causing no growth enhancement over five days in cells from lipid-infused animals. Thus, atherogenic infusions of Lipofundin-S into rats cause phenotypic changes in arterial SMC which can be passed to successive cell generations in vitro. 相似文献