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101.
Outbreaks of methicillin-resistant Staphylococcus aureus (MRSA) in the neonatal intensive care unit (NICU) have been reported worldwide. Some outbreaks were caused by USA300, which is a community-associated MRSA clone. In 2011, polymerase chain reaction-based open reading frame typing (POT) for the initial MRSA isolates from all inpatients was started at the Tokyo Metropolitan Children's Medical Center. From March 2014 to April 2015, a total of 131 MRSA strains were isolated, 104 of which were analyzed as healthcare-associated MRSA. Thirteen stains (12.5%) had a POT number of 106-9-93, which strongly suggested USA300; these included 6 from nasal swabs, 6 from blood cultures and 1 from subcutaneous pus. All the MRSA strains were isolated from patients in the NICU; were typed as sequence type 8, spa type t008, and staphylococcal cassette chromosome type mec IVa; and possessed the lukS-lukF and arginine catabolic mobile element-arcA gene. Pulsed-field gel electrophoresis of all the strains, with USA300-0114 as a reference, showed indistinguishable banding pattern. Based on these results, POT was useful in recognizing this first MRSA outbreak of USA300 in a Japanese NICU and was advantageous in terms of swiftness, less cost and monitoring change of the epidemic MRSA lineage.  相似文献   
102.
Persistent Gram-negative rod (GNR) bacteremia is uncommon under appropriate antibiotic therapy. A recent study showed that follow-up blood cultures (FUBCs) to confirm clearance 24–48 h after initiation of antibiotics, added little value in the management of GNR bacteremia in adults. However, the utility of FUBC in children is still unknown. We retrospectively reviewed the microbiology database to identify children aged <18 years with GNR bacteremia. Clinical information including gender, age, underlying diseases, presence of central venous line (CVC), source of bacteremia, and organisms was extracted from medical records. FUBCs for 99 episodes of GNR bacteremia in children became positive in 21%, which led to intervention in 57% of the episodes. In multivariate analysis between FUBC positive (n = 21) and negative (n = 78) groups, presence of CVC (n = 18, 86% vs n = 38, 49%, P = 0.001) and resistance to empirical antibiotics (n = 3, 14% vs n = 4, 5%, P = 0.04) were independently associated with positive FUBCs. Interestingly, no positive FUBC was observed in cases due to UTI (n = 13). Contrary to findings in adults, FUBC may still be useful in the management of GNR bacteremia in children.  相似文献   
103.
Summary A 25-year-old woman with acute dyspnea was found to have nodular shadows in a chest X-ray film. Multiple defects in a perfusion scan indicated pulmonary embolization. The cause of acute cor pulmonale was extensive metastatic embolization from chondrosarcoma of the calf. Embolization by metastasis as a rare occurrence resulting in acute cor pulmonale should be considered in patients with a malignant tumor.  相似文献   
104.
The relationships among perioperative changes in plasma antithrombin (AT) activity, platelet counts, and clinical risk factors for postoperative thromboembolism has not been studied extensively in gynecologic patients. AT activity and platelet counts were determined preoperatively and on postoperative days 1 and 7 in 74 patients who underwent gynecologic surgery. The relationships between each clinical risk factor for postoperative thromboembolism and the decrease in AT activity and platelet count were analyzed using a univariate logistic regression model. No clinically significant thromboembolism occurred in any patient. AT activity and platelet counts decreased significantly on postoperative day 1 and exceeded preoperative levels on day 7. Postoperative patients with malignancy were more likely to exhibit decreased AT activity. AT activity decreased significantly with increases in operating time and blood loss. Known risk factors for postoperative thromboembolism did not appear to be associated with postoperative decreases in platelet counts. Transient hyperconsumption of AT and platelets occurs immediately after gynecologic surgery. Surgery-induced AT deficiency may contribute to postoperative thromboembolism in patients with long operating times and significant blood loss.  相似文献   
105.
Multiple studies have shown that phospholamban (PLN) plays a key role in regulation of frequency-dependent increase of cardiac contraction, a hallmark of the contractile reserve in myocardium. However, the mechanisms underlying this relationship remain elusive. Phosphorylation of PLN occurs on residues: serine-16 (Ser(16)) and threonine-17 (Thr(17)) in vivo. In isolated wild-type cardiomyocytes, we found that increases of stimulation frequency from 0.5 to 5 Hz were associated with increased Thr(17) phosphorylation of PLN and cardiac contractility. To further delineate the role of PLN phosphorylation in the frequency-dependent increases of cardiac function, three transgenic mouse models, expressing wild-type, Ser16Ala (S16A), or Thr17Ala (T17A) mutant PLN in the null background were generated. Transgenic lines expressing similar levels of wild-type or mutant PLN were selected and isolated cardiomyocytes were paced from 0.5 to 5 Hz. Upon increases in pacing frequency, the fractional shortening (FS) and rates of contraction (+dL/dt) and relaxation (-dL/dt) increased in wild-type and S16A mutant PLN cardiomyocytes. In contrast, in myocytes expressing the T17A mutant PLN, there were no increases in FS and +/-dL/dt upon increasing the frequency of stimulation. The time to 50% peak shortening (TTP(50)) and to 50% relaxation (TTR(50)) were also abbreviated to a much higher extent (two-fold) in wild-type and S16A mutant compared to T17A mutant PLN cardiomyocytes. These results indicate that Thr(17) phosphorylation of PLN is the major contributor to frequency-dependent increases of contractile and relaxation parameters in mouse cardiomyocytes, although some increases in these parameters occur even in the absence of PLN phosphorylation. Thus, the positive force-frequency relationship in cardiomyocytes is mechanistically and mainly related to PLN phosphorylation.  相似文献   
106.
Background: It has been widely accepted that control of serum cholesterol levels is effective for prevention of cardiovascular events. Recent data have suggested that this is also the case in the elderly. Methods: A research group (chaired by T. Kita) was organized as part of the Comprehensive Research on Aging and Health conducted by the Japanese Ministry for Health, Labour, and Welfare in 1999–2002 to determine the best strategy for control of cholesterol levels in elderly Japanese with hypercholesterolemia. In order to do this a review of the literature was conducted. Conclusion: The research group concluded: (i) Japanese patients aged 65–74 years with hypercholesterolemia should be treated by following the Guideline for Diagnosis and Treatment of Atherosclerotic Cardiovascular Diseases by the Japan Atherosclerosis Society (2002), as cholesterol‐lowering therapy would bring a similar, or even larger, preventive effect to the elderly, whose absolute risk of cardiovascular events is higher than that in the younger population; (ii) target cholesterol levels in elderly Japanese aged ≥ 75 years with hypercholesterolemia should be determined individually according to their physical activities. It is noted that the elderly are more susceptible to drug‐related adverse effects than the younger since renal and liver functions, required for metabolizing drugs, in the elderly are relatively weaker.  相似文献   
107.
ObjectiveTo present our results of the external auditory canal (EAC) reconstruction procedure using rolled-up full-thickness skin graft with tympanoplasty after lateral temporal bone resection (LTBR) for early-stage EAC carcinoma.Patients and MethodsA retrospective review of 15 patients who had undergone LTBR with reconstruction of the EAC for T1 and T2 EAC cancer between 2016 and 2020.ResultsPostoperative mean air-bone gap was 30.7 decibel hearing level. Although a few patients experienced chronic granulation, persistent otorrhea, and/or laterization of the tympanic membrane, most patients showed no serious complications related to the EAC reconstruction.ConclusionEAC reconstruction using a full-thickness skin graft in combination with tympanoplasty is useful for minimizing the hearing loss, maintaining the cosmetic appearance, and facilitating the observation into the ear cavity.  相似文献   
108.
109.
Journal of Natural Medicines - Two new steroidal saponins, scrobiculosides A and B, were isolated from the deep-sea sponge Pachastrella scrobiculosa, collected at a depth of 200&nbsp;m off...  相似文献   
110.
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