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1.
A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.  相似文献   
2.
Growth hormone-releasing factor (GRF) synthesizing neuronal perikarya and terminals were investigated by light and electron microscopic immunocytochemistry using rat hypothalamus. Immunoreactive neuronal perikarya were located mainly in the ventrolateral part of the arcuate nucleus. They contained well developed cell organella such as mitochondria and rough surfaced endoplasmic reticulum with some expansion. They also contained immunoreactive dense granules (80-120 nm in diameter). On the surface of the immunoreactive neuronal perikarya were frequently found non-immunoreactive axo-somatic synapses. Therefore, the GRF-like immunoreactive neurons were assumed to receive neuronal inputs from other neurons on their neuronal soma. In the external layer of the median eminence large numbers of immunoreactive terminals were distributed particularly around the capillaries of the portal vessel. Electron microscopic immunocytochemistry revealed large numbers of immunoreactive terminals containing immunoreactive dense granules, synaptic vesicles and mitochondria in the vicinity of the basement membrane of the pericapillary space of the portal vessel. Therefore, we concluded that GRF-like immunoreactive substances are released into the portal capillaries from the nerve terminals, which originate from the neuronal perikarya in the ventrolateral part of the arcuate nucleus, and act on growth hormone release in the anterior pituitary. We also suggest that GRF-like immunoreactive neurons have abundant terminal arborization in the external layer of the median eminence.  相似文献   
3.
Electrocatalytic dehalogenation of organohalides was studied using a nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode. The nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode was prepared by attaching nickel(II) (6-(2′-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)perchlorate chemically to the carboxyl groups of a thin poly(acrylic acid) layer coated on the graphite felt. The modified electrode gave a reversible electron transfer for the nickel(II)/nickel(I) redox couple in cyclic voltammetry at ?0.95 V versus Ag/AgCl. A preparative electrocatalytic dehalogenation of organohalides was successfully achieved on the modified electrode with an adequate current efficiency (55.6–94.8%), conversion (34.2–100%) and turnover number of the Ni catalyst (667–3333).  相似文献   
4.
We compared the effect of seton (White pump shunt) surgery (16 eyes) with that of trabeculectomy and 5-fluorouracil (31 eyes) in treating 38 Asian patients with medically uncontrollable neovascular glaucoma. We found the probability of long-term success (intraocular pressure < or = 26 > or = 5 mm Hg) of seton surgery (53.0% at 3 years) to be similar to that obtained following trabeculectomy with adjunctive 5-fluorouracil (45.4% at 3 years). However, 3 years postoperatively, the probability of the preservation of visual acuity was significantly greater following trabeculectomy than seton surgery (67.1% vs 23.1%; P < .05). In addition, the prevalence of postoperative complications was higher with the seton procedure (P < .001). The loss of endothelial cells 6 months postoperatively was more marked with seton surgery than with trabeculectomy, whether the shunt device touched the cornea (P < .000001) or not (P < .0005). In conclusion, White's pump shunt was effective in lowering the IOP of eyes with neovascular glaucoma. However, care must be taken to prevent postoperative complications, the incidence of which exceeded those observed following trabeculectomy with adjunctive 5-fluorouracil.  相似文献   
5.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
6.
7.
Priming effect of RANTES on eosinophil oxidative metabolism   总被引:1,自引:0,他引:1  
Background RANTES has been shown to possess chemotactic activity for eosinophils, which have also been considered to play a role in allergic inflammation through reactive oxygen species. Thus, in this study, we examined the effect of RANTES on radical oxygen products from eosinophils.
Methods Purified eosinophils by CD16-negative selection or an eosinophilic cell line (EoL-1) were incubated with or without RANTES (2.5 x 10−6). To the mixture of eosinophils and luminol, calcium ionophore (A23187) or opsonized zymosan (OZ) was added, and radical oxygen products were determined by luminol-dependent chemiluminescence for 600 s.
Results Eosinophil-mediated radical oxygen products of untreated eosinophils produced with A23187 gave a peak value of 14.09 + 2.40 (mean±SE, n = 12) relative light units (RLU) and an integrated value of 3232.20 + 513.09 RLU. However, with treatment with RANTES, a peak value of 18.66 + 2.40 RLU and an integrated value of 5301.05 ±561.02 RLU were obtained. Eosinophil oxidative metabolism-induced A23187 or OZ was apparently augmented by the preincubation with RANTES. In addition, the radical oxygen products of EoL-1 showed similar results.
Conclusions Thus, we concluded that RANTES may play an important role the pathogenesis of allergic inflammation through its involvement in eosinophil activation, as evidenced by oxygen products, as well as in selective eosinophil infiltration as selective eosinophil chemoattractant.  相似文献   
8.
Expression of the Arabidopsis CGS1 gene that codes for cystathionine gamma-synthase is feedback regulated at the step of mRNA stability in response to S-adenosyl-L-methionine (AdoMet). A short stretch of amino acid sequence, called the MTO1 region, encoded by the first exon of CGS1 itself is involved in this regulation. Here, we demonstrate, using a cell-free system, that AdoMet induces temporal translation elongation arrest at the Ser-94 codon located immediately downstream of the MTO1 region, by analyzing a translation intermediate and performing primer extension inhibition (toeprint) analysis. This translation arrest precedes the formation of a degradation intermediate of CGS1 mRNA, which has its 5' end points near the 5' edge of the stalled ribosome. The position of ribosome stalling also suggests that the MTO1 region in nascent peptide resides in the ribosomal exit tunnel when translation elongation is temporarily arrested. In addition to the MTO1 region amino acid sequence, downstream Trp-93 is also important for the AdoMet-induced translation arrest. This is the first example of nascent peptide-mediated translation elongation arrest coupled with mRNA degradation in eukaryotes. Furthermore, our data suggest that the ribosome stalls at the step of translocation rather than at the step of peptidyl transfer.  相似文献   
9.
C-reactive protein levels in the serum of asthmatic patients.   总被引:1,自引:0,他引:1  
BACKGROUND: Asthma is a chronic airway inflammatory disease caused by immune cells such as T lymphocytes and eosinophils. Recently, highly sensitive C-reactive protein (hs-CRP) assays have become available for detecting small changes in CRP levels within the reference range, allowing for the evaluation of clinical inflammation. OBJECTIVE: To investigate the relationship between hs-CRP levels and bronchial asthma. METHODS: We collected blood samples from 109 patients with bronchial asthma, with or without attacks, and measured serum eosinophil cationic protein levels, pulmonary function, and serum CRP levels using an hs-CRP assay. RESULTS: Mean serum hs-CRP levels were significantly higher in patients without attacks (0.473 mg/L) and with attacks (0.908 mg/L) (P < .001 for both) than in controls (0.262 mg/L). Serum hs-CRP levels were inversely correlated with forced expiratory volume in 1 second/forced vital capacity in asthmatic patients (r = -0.4915; P < .01). CONCLUSION: Serum hs-CRP levels may be related to the state of asthma exacerbation and allergic inflammation.  相似文献   
10.
We have studied the contribution of c-Fos/activator protein-1 (AP-1) to antigen-specific T cell response with reference to T cell anergy by increasing c-Fos/AP-1 in vivo and in vitro. First, after injection of a high dose of staphylococcus enterotoxin B (SEB), clonal deletion of SEB-reactive V(beta)8(+) CD4 T cells occurred both in control B6 and H2-c-fos transgenic (fos) mice, whereas proliferation of T cells against SEB was profoundly depressed in B6 but not in fos mice. Second, the keyhole limpet hemocyanin-specific CD4 T(h)1 cell clone produced decreasing amounts of IL-2 in response to increasing amounts of concanavalin A (Con A) in vitro, whereas the decrease was less significant in the T(h)1 clones stably transfected with c-fos gene. Electrophoretic mobility shift assay with nuclear protein from the transformants showed that overexpression of the c-fos gene compensated the amounts of AP-1 in the nuclei of Con A-treated T(h)1 clones. Thus, increased c-Fos/AP-1 confers resistance against anergy induction on antigen-specific T cells.  相似文献   
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