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1.
ABSTRACT. The efficacy of low-dose doxapram therapy (0.2 mg/kg/h) in combination with methylxanthines was evaluated in 20 premature infants with idiopathic apnea unresponsive to methylxanthines alone, and in 13 premature infants with secondary apnea. The serum concentrations of doxapram and, in some infants, the simultaneous cerebrospinal fluid and serum concentrations were measured, and the correlation between cerebrospinal fluid and serum concentrations in the postnatal period was determined. The following results were obtained: 1) In idiopathic apnea of prematurity, low-dose doxapram therapy was as effective as a dose of 1.0-2.5 mg/kg/h and the side effects were few, mild, and reversible. 2) In premature infants over seven days of age, serum concentrations of doxapram were almost stable but were significantly lower than in infants within the first six days of life. 3) The ratio of the cerebrospinal fluid to serum doxapram concentration was 0.48 ± 0.13 (mean ± SD). There was a good correlation between cerebrospinal fluid and serum concentrations ( r = 0.933, p < 0.001). The initial doxapram dose can be set as low as 0.2 mg/kg/h in very young premature infants with idiopathic apnea of prematurity unresponsive to methylxanthines.  相似文献   
2.
Abstract: This case report describes a patient with a rectal ulcer who had an unusual defecation habit. Complete healing was recognized colonoscopically after the patient was instructed to break this habit. A polyp of the ascending colon was detected by a barium enema in a 37-year-old man complaining of anal bleeding. He was admitted to our division to undergo a polypectomy. At the time of the polypectomy, a round ulcer, measuring 1 cm in diameter, was detected on the right wall of the rectum 3 cm from the anal verge. A diagnosis of mucosal prolapse syndrome of the rectum could not be made because the patient did not exhibit the characteristic habit of excessive “straining” mentioned by patients with this syndrome, and no characteristic finding of fibromuscular obliteration was found on histological examination of biopsied specimens taken endoscopically from the lesion. Repeated history taking, however, revealed that the patient had the unusual habit of inserting his finger into his rectum after defecation. He broke this habit following instruction to do so. As a result, on colonoscopic examination 15 month later, the ulcer was found to have become a scar:  相似文献   
3.

Background  

Single-nucleotide polymorphisms (SNPs) are considered to be useful polymorphic markers for genetic studies of polygenic traits. Single-stranded conformational polymorphism (SSCP) analysis has been widely applied to detect SNPs, including point mutations in cancer and congenital diseases. In this study, we describe an application of the fluorescent labeling of PCR fragments using a fluorescent-adapted primer for SSCP analysis as a novel method.  相似文献   
4.
BACKGROUND: Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE: Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN: Case series. SETTING AND PATIENTS: A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION: ESD. MAIN OUTCOME MEASUREMENTS: En bloc resection rate, complete resection rate, operation time, and complications. RESULTS: En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION: Short duration of follow-up. CONCLUSIONS: ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists.  相似文献   
5.
Abstract: Background/Aims: The molecular mechanism involved in hepatocellular injury in viral hepatitis remains to be clarified. Methods: We investigated the in situ expression of effector molecules of cytotoxic T lymphocytes such as Fas‐ligand (Fas‐L), perforin and Granzyme B (Gr‐B) immunohistochemically in liver tissues from 20 patients with chronic hepatitis B (CHB) and C (CHC). The degree of cell infiltration was analysed semi‐quantitatively and compared with the histological activity index (HAI). Fas‐L was expressed in both CD4 and CD8 T‐cells in the portal tract as well as in the parenchyma. Results: Immunostaining of serial sections demonstrated that mononuclear cells at interface hepatitis and focal necrosis were mainly Fas‐L positive CD8 T‐cells. On the other hand, the expression of perforin or Gr‐B was limited to a few mononuclear cells in the portal tract and parenchyma. Semi‐quantitative analysis showed a positive correlation between HAI and the grade of infiltration of CD8 T‐cells or Fas‐L‐positive cells, while the correlation was not apparent between HAI and the number of Gr‐B positive cells. The expression of these molecules was not different between types of viruses. Conclusions: These results suggest that Fas‐L‐positive CD8 T‐cells play a major role in the pathogenesis of liver cell injury in chronic hepatitis.  相似文献   
6.
5-Aminolevulinic acid (ALA) is a naturally occurring amino acid present in diverse organisms and a precursor of heme biosynthesis. ALA is commercially available as a component of cosmetics, dietary supplements, and pharmaceuticals for cancer diagnosis and therapy. Recent reports demonstrated that the combination of ALA and ferrous ion (Fe2+) inhibits the in vitro growth of the human malaria parasite Plasmodium falciparum. To further explore the potential application of ALA and ferrous ion as a combined antimalarial drug for treatment of human malaria, we conducted an in vivo efficacy evaluation. Female C57BL/6J mice were infected with the lethal strain of rodent malaria parasite Plasmodium yoelii 17XL and orally administered ALA plus sodium ferrous citrate (ALA/SFC) as a once-daily treatment. Parasitemia was monitored in the infected mice, and elimination of the parasites was confirmed using diagnostic PCR. Treatment of P. yoelii 17XL-infected mice with ALA/SFC provided curative efficacy in 60% of the mice treated with ALA/SFC at 600/300 mg/kg of body weight; no mice survived when treated with vehicle alone. Interestingly, the cured mice were protected from homologous rechallenge, even when reinfection was attempted more than 230 days after the initial recovery, indicating long-lasting resistance to reinfection with the same parasite. Moreover, parasite-specific antibodies against reported vaccine candidate antigens were found and persisted in the sera of the cured mice. These findings provide clear evidence that ALA/SFC is effective in an experimental animal model of malaria and may facilitate the development of a new class of antimalarial drug.  相似文献   
7.
The process and the site of hepatitis C virus (HCV) particle formation in cells after infection remain unknown. The aim of this study was to create an in vitro model for the study of HCV particle formation. HeLa G cells were transfected with the full-length sequence of the HCV genome. Viral protein expression was analyzed using immunoblotting. The cells were examined using immunoelectron and conventional electron microscopy. Core, E2, NS3, NS5a, and NS5b proteins were identified using immunoblotting. Immunoelectron microscopy showed that the core antigen was located along the membrane of the endoplasmic reticulum (ER) and occasionally in its cisternae. Core antigen-positive particles of 30 nm in diameter were found in the cytosol and in the cisternae of the ER. The particles in the cisternae were coated with an outer membrane that was connected to the ER membrane. Conventional electron microscopy revealed particles of 45 nm in diameter with electrondense cores in the cisternae of the ER. The outer membrane of the particles was occasionally connected to the ER membrane. The findings suggest that HCV core proteins are synthesized and assembled into particles in the cytosol and that they bud into the cisternae of the ER to form coated particles.  相似文献   
8.
Ventricular Tachycardia After Alcohol Septal Ablation. A 76‐year‐old female developed 2 different ventricular tachycardias (VTs) 5 years after alcohol septal ablation (ASA) for symptomatic hypertrophic obstructive cardiomyopathy. VT#1 was a small macroreentry at the anterior border of the low‐voltage zone, suggesting the ASA‐scar and eliminated by endocardial ablation at a site recording fractionated potentials covering the mid‐diastolic and presystolic periods. VT#2 was a focal VT and eliminated by epicardial cryoablation at the basal posterior left ventricle, suggesting the posterior border of the ASA‐scar. Using the electroanatomical mapping, we demonstrated that the mechanism of the VTs was reentry at the edge of the ASA‐scar. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1296‐1299, November 2010)  相似文献   
9.
10.
The role of growth factor networks in regulating the progression of human melanocytes towards tumorigenicity and ultimately the malignant phenotype is poorly understood. In particular, the autocrine and paracrine influences that modulate cellular invasion and extracellular matrix degradative enzymes of melanoma cells remain undefined at the molecular level. We report here that nerve growth factor (NGF) can modify some metastasis-associated cellular properties of human and mouse melanoma cells. Treatment of early-passage human metastatic melanoma cells (MeWo) or their variants (3S5, 70W) with biologically active 2.5S NGF resulted in (a) delayed density-dependent inhibition of melanoma cell growth; (b) increased in vitro invasion through a reconstituted basement membrane; and (c) time- and dose-dependent induction of heparanase, a heparan-sulfate-specific endo-β-D-glucuronidase associated with human melanoma metastasis. These effects of NGF were most marked in the 70W brain-colonizing cells (70W > MeWo > 3S5). The NGF enhancement of heparanase secretion was not species-specific, since it was also observed in murine B16 melanoma cells; the highest NGF stimulation of heparanase was found in brain-colonizing murine B16-B15b variant (B16-B15b > B16-BL6, B16-F10, B16-F1). NGF also increased the invasive capacity of the human 70W and murine B16-B15b sublines in a chemoinvasion assay performed with filters coated with purified heparan sulfate proteoglycan (HSPG). The enhancement of chemotactic response and heparanase production was detected at NGF concentrations sufficient to fully saturate both low- and high-affinity NGF receptors (NGFR), the neurotrophin receptor (p75) and the trkA gene product, respectively. The results suggest that, in addition to the effects of NGF on cellular development and differentiation within the peripheral and central nervous systems, NGF can exert changes in the invasive properties of neuroectoderm-derived melanoma cells.  相似文献   
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