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81.
Diagnostic imaging is undoubtedly important in modern medicine, and final clinical decisions are often made based on it. Fortunately, Japan has the highest numbers of diagnostic imaging instruments, such as CT and MRI devices, and boasts easy access to them as well as a high level of diagnostic accuracy. In consequence, a very large number of imaging examinations are performed, but diagnostic instruments are installed in so many medical facilities that expert management of these examinations tends to be insufficient. Particularly, in order to avoid risks, clinicians have recently become indifferent to indications of imaging modalities and tend to rely on CT or MRI resulting in increasing the number of imaging examinations in Japan. This is a serious problem from the viewpoints of avoidance of unnecessary exposure and medical economy. Under these circumstances, the Japan Radiological Society and Japanese College of Radiology jointly initiated the preparation of new guidelines for diagnostic imaging. However, the field of diagnostic imaging is extremely wide, and it is impossible to cover all diseases. Therefore, in drafting the guidelines, we selected important diseases and focused on “showing evidence and suggestions in the form of clinical questions (CQs)” concerning clinically encountered questions and “describing routine imaging techniques presently considered to be standards to guarantee the quality of imaging examinations”. In so doing, we adhered to the basic principles of assuming the readers to be “radiologists specializing in diagnostic imaging”, “simultaneously respecting the global standards and attending to the situation in Japan”, and “making the guidelines consistent with those of other scientific societies related to imaging”. As a result, the guidelines became the largest ever, consisting of 152 CQs, nine areas of imaging techniques, and seven reviews, but no other guidelines in the world summarize problems concerning diagnostic imaging in the form of CQs. In this sense, the guidelines are considered to reflect the abilities of diagnostic radiologists in Japan. The contents of the guidelines are essential knowledge for radiologists, but we believe that they are also of use to general clinicians and clinical radiological technicians. While the number and contents of CQs are still insufficient, and while chapters such as those on imaging in children and emergency imaging need to be supplemented, the guidelines will be serially improved through future revisions. Lastly, we would like to extend our sincere thanks to the 153 members of the drafting committee who authored the guidelines, 12 committee chairpersons who coordinated their efforts, six members of the secretariat, and affiliates of related scientific societies who performed external evaluation.  相似文献   
82.
83.
Summary The C-terminal R peptide of ecotropic murine leukemia virus (MLV) envelope protein (Env) negatively controls membrane fusion activity. The R peptide cleavage during virion maturation activates its fusogenicity and is required for viral entry. We analyzed fusogenicity and transduction efficiency of mutant Env proteins of ecotropic, amphotropic, polytropic, and xenotropic MLVs. As the result, we found that the hydrophobic amino acid residues around the R peptide cleavage site are important for membrane fusion inhibition by the R peptide. In addition, we found that Env complexes with R peptide-truncated and -containing Env proteins have lower fusogenicity and transduction efficiency than those with the R-peptide-truncated Env alone, suggesting that efficient R peptide cleavage is required for efficient MLV vector transduction. The role of R peptide cleavage in amphotropic, polytropic, and xenotropic MLV infection has not been investigated. We found in this study that the R peptide cleavage is required for amphotropic, xenotropic, and polytropic MLV vector transduction, like with ecotropic MLV. The R-peptide-truncated Env proteins of the xenotropic and polytropic MLVs, however, had much lower fusogenicity than those of the ecotropic and amphotropic MLVs. These results provide valuable information for construction of efficient MLV vectors and for understanding the retroviral entry mechanism.  相似文献   
84.

Purpose

The aim of this study was to investigate the outcomes correlated with our treatment strategy for prosthetic graft infection.

Methods

Seventeen patients were treated for prosthetic graft infections between 1997 and 2009. Initially, total graft excision was applied in five cases, partial graft excision was applied in six cases and graft preservation with drainage and irrigation was applied in six cases. Among the graft-preserved cases, four patients were infected with methicillin-resistant Staphylococcus aureus (MRSA) and treated with gentian violet (GV).

Results

The overall survival rate was 88 % at 30 days and 82 % at 1 year in this series. Of the excised cases, nine patients survived; however, two patients died. Among the cases in which MRSA-infected grafts were preserved, three patients survived; however, one patient died under a septicemic state. Infected graft preservation was applied at a high rate of 36 %, and the mortality rate remained at 16 %, without any signs of graft reinfection.

Conclusions

In the treatment of infected grafts, the patient’s condition should be considered in order to select the appropriate treatment in each case. Graft preservation should be considered as an alternative treatment option, especially in high-risk patients, and GV can be effective for conservative treatment of prosthetic graft infections, including MRSA infections.  相似文献   
85.

Background

We determined mid to long-term results of total elbow arthroplasty (TEA) by use of unlinked elbow prostheses with solid alumina ceramic trochleae, and ceramic ulnar stems (stemmed Kyocera type I; SKC-I) for patients with rheumatoid arthritis.

Patients and methods

Fifty-four elbows of 39 patients were available for detailed clinical and radiographic review after a follow-up period of at least 5 years. The mean follow-up period was 12.6 years (range 5–22 years). Clinical condition before and after surgery was assessed by use of a modified version of the Mayo Elbow Performance Score (MEPS; 0–100 points) and a Japan Orthopaedic Association Elbow score (JOA score; 0–100 points). The radiographs were reviewed and loosening was defined as a progressive radiolucent line >1 mm wide that was completely circumferential around the prosthesis. Clinical records of post-operative events affecting the elbows were used for survival analysis of the prostheses using the Kaplan–Meier method.

Results

The average modified MEPS and JOA scores improved significantly from 39.7 ± 14.3 to 44.7 ± 9.4, respectively, pre-operatively, to 89.7 ± 15.4 and 83.1 ± 12.8, respectively, post-operatively (P < 0.0001). The functional assessment score also improved from 4.9 ± 2.8 to 8.5 ± 3.3 points (P < 0.0001). With loosening or implant revision defined as end points, the likelihood of survival of the prosthesis for up to 20 years was 92.6 % (95 % confidence interval (CI), 85.6–100.0) or 86.3 % (95 % CI 75.0–97.6), respectively.

Conclusion

Satisfactory clinical results were obtained after TEA using SKC-I prostheses, which provided excellent pain relief and functional range of motion. The results of our study reveal the high reliability over a long period of the cemented SKC-I prosthesis with an alumina ceramic component.  相似文献   
86.
87.
Using the transition from cytosine of BFP (blue fluorescent protein) gene to uridine of GFP (green fluorescent protein) gene at position 199 as a model, we successfully controlled photochemical RNA editing to effect site‐directed deamination of cytidine (C) to uridine (U). Oligodeoxynucleotides (ODNs) containing 5′‐carboxyvinyl‐2′‐deoxyuridine (CVU) were used for reversible photoligation, and single‐stranded 100‐nt BFP DNA and in vitro‐transcribed full‐length BFP mRNA were the targets. Photo‐cross‐linking with the responsive ODNs was performed using UV (366 nm) irradiation, which was followed by heat treatment, and the cross‐linked nucleotide was cleaved through photosplitting (UV, 312 nm). The products were analyzed using restriction fragment length polymorphism (RFLP) and fluorescence measurements. Western blotting and fluorescence‐analysis results revealed that in vitro‐translated proteins were synthesized from mRNAs after site‐directed RNA editing. We detected substantial amounts of the target‐base‐substituted fragment using RFLP and observed highly reproducible spectra of the transition‐GFP signal using fluorescence spectroscopy, which indicated protein stability. ODNc restored approximately 10% of the C‐to‐U transition. Thus, we successfully used non‐enzymatic site‐directed deamination for genetic restoration in vitro. In the near future, in vivo studies that include cultured cells and model animals will be conducted to treat genetic disorders.  相似文献   
88.
Esophagus - Talaporfin sodium photodynamic therapy (tPDT) is an effective salvage treatment for local failure after chemoradiotherapy for esophageal cancer. Repeated tPDT could also be indicated...  相似文献   
89.
90.
We investigated the cross-sectional relationship between ankle brachial index and cardiovascular disease risk factors, including C-reactive protein (CRP), among Japanese elderly, a topic which has had little prior epidemiologic study. Our study population comprised 946 subjects aged at least 70 years in whom both CRP and ankle brachial index were measured. The participants were classified into a low (ankle brachial index<0.9) and normal ankle brachial index group. We found that current smoking, high-density lipoprotein cholesterol <40 mg/dl, a low body mass index (continuous variable), hypertension, diabetes and statin use were all significantly related to a lower ankle brachial index. Higher log-transformed CRP level was significantly related to a lower ankle brachial index after adjustment for the cardiovascular risk factors mentioned above (p <0.01). The odds ratios for low ankle brachial index compared to 0-1 risk factors were 5.79 (95% confidence interval [CI]: 2.99-11.20) for 2 risk factors and 17.45 (95% CI: 6.78-49.91) for 3 or more risk factors; independently of other risk factors, the odds ratio for CRP>1.0 mg/l was 2.10 (95% CI: 1.13-3.88) compared to lower CRP values. Thus, a high level of CRP is related to a low ankle brachial index among Japanese elderly as well as Western subjects. This is the first study to report the relationship between CRP and low ankle brachial index among Japanese elderly.  相似文献   
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