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The maize floury 2 (fl2) mutation enhances the lysine content of the grain, but the soft texture of the endosperm makes it unsuitable for commercial production. The mutant phenotype is linked with the appearance of a 24-kDa alpha-zein protein and increased synthesis of binding protein, both of which are associated with irregularly shaped protein bodies. We have cloned the gene encoding the 24-kDa protein and show that it is expressed as a 22-kDa alpha-zein with an uncleaved signal peptide. Comparison of the deduced N-terminal amino acid sequence of the 24-kDa alpha-zein protein with other alpha-zeins revealed an alanine to valine substitution at the C-terminal position of the signal peptide, a histidine insertion within the seventh alpha-helical repeat, and an alanine to threonine substitution with the same alpha-helical repeat of the protein. Structural defects associated with this alpha-zein explain many of the phenotypic effects of the fl2 mutation.  相似文献   
43.
目的探讨阴道超声早期诊断异位妊娠的价值,分析其漏、误诊原因。方法对43例临床可疑异位妊娠的患者进行经阴道超声检查。结果经阴道超声提示宫外孕38例,宫内妊娠4例,宫内外均未见妊娠1例。经腹腔镜或剖腹手术病理结果证实,共有37例输卵管妊娠,)例卵巢妊娠,其中l例输卵管妊娠宫内假孕囊误诊为宫内妊娠,1例输卵管妊娠漏诊,2例宫内妊娠卵巢黄体误诊为输卵管妊娠,超声诊断符合率89.5%,漏、误诊率10.53%。结论经阴道超声诊断异位妊娠准确度较高,但有一定漏、误诊。结合病史和临床表现、综合分析超声图像特征有助于提高早期诊断符合率。  相似文献   
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While assessing the prognostic implications of immunophenotyping in 382 patients enrolled in treatment protocols of the Eastern Cooperative Oncology Group (ECOG) for de novo adult acute myeloid leukaemia, we identified 95 patients with a unique antigen profile characterized by high expression of the leucocyte integrin CD11b (CD11b+ AML). High expression of CD11b was defined as 32% positive blasts based on the retrospectively established prognostic cut-off point for this antigen. Although CD11b is normally expressed by mature monocytes, natural killer cells and granulocytes, leukaemic blasts in CD11b+ AML lacked other immunologic monocytic features (e.g. CD14 and CD122, the interleukin-2 receptor β chain) and demonstrated a high degree of immaturity, as reflected by a high incidence of blasts expressing the stem cell factor receptor, CD117, and few blasts positive for the myeloid differentiation antigen CD15. Furthermore, by FAB criteria, only 41% of CD11b+ AML cases were classified as M4/M5. Patients with CD11b+ AML had a low response rate (54%) when compared with acute monocytic leukaemia (AMOL; 82%, P  = 0.006) or AML overall (68%, P  = 0.031), independent of age, cytogenetic abnormalities and P-glycoprotein expression. Because of its poor prognosis, recognition of CD11b+ AML is clinically warranted and, given its morphologic and cytogenetic ambiguity, must be based on the unique antigen profile.  相似文献   
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Background

Medication-related osteonecrosis of the jaw (MRONJ) is clinically defined as a non-healing jawbone ulcerative-necrotic lesion appearing after dental therapy or minor trauma in patients treated previously with anti-resorptive, anti-angiogenic or immunomodulators. Older patients with osteoporosis and cancer receive these pharmacological agents regularly. As these patients are long-term survivors, efficient treatment is of paramount importance for their quality of life.

Methods

Literature searches via PubMed were conducted to identify relevant MRONJ studies. Basic information on MRONJ classification, clinical features, and pathosphysiology is presented herein as well as various clinical studies dealing with MRONJ in patients with osteoporosis and cancer. Lastly, we discuss current managment of patients and new trends in treatment of MRONJ.

Results

Although close follow-up and local hygiene have been advocated by some authors, severe forms of MRONJ are not responsive to conservative therapy. At present, there is no “gold standard” therapy for this condition. However, as the physiopathological basis of MRONJ is represented by the anti-angiogenic action of various pharmacological agents, new methods to increase and promote local angiogenesis and vascularization have recently been successfully tested in vitro, limited preclinical studies, and in a pilot clinical study.

Conclusions

It appears that the best method implies application on the lesion of endothelial progenitor cells as well as pro-angiogenic factors such as Vascular Endothelial Growth Factor (VEGF) and other related molecules. More recently, scaffolds in which these factors have been incorporated have shown positive results in limited trials. However, these studies must be replicated to include a large number of cases before any official therapeutic protocol is adopted.  相似文献   
48.
BACKGROUND: The catechol O-methyltransferase inhibitor entacapone acts by extending the elimination half-life of levodopa and is currently approved as an adjunct to levodopa for the treatment of patients with Parkinson disease (PD) with motor fluctuations. OBJECTIVE: To determine if the addition of entacapone administration provides benefit to levodopa-treated PD patients who have a stable response to levodopa and do not experience motor complications. DESIGN: Prospective, double-blind, placebo-controlled trial. SETTING: Outpatient multicenter study. PATIENTS: Female and male patients 30 years or older with idiopathic PD receiving stable doses of levodopa or carbidopa with or without other dopaminergic therapies and who did not experience motor fluctuations were eligible for the study. MAIN OUTCOME MEASURES: Parkinsonian function and quality of life. RESULTS: The addition of entacapone did not improve motor scores on the Unified Parkinson's Disease Rating Scale in levodopa-treated PD patients who did not experience motor fluctuations. The mean +/- SE adjusted change between baseline and final treatment visit was -0.9 +/- 0.35 in the entacapone group and -0.8 +/- 0.35 in the placebo group (P = .83). Significant improvement with entacapone treatment was detected in several quality-of-life measures, including the Parkinson Disease Questionnaire 39, the 36-item Short-Form Health Survey, the Parkinson's Symptom Inventory, and investigator and subject Clinical Global Assessments. The drug was well tolerated by patients in this population. CONCLUSIONS: The catechol O-methyltransferase inhibitor entacapone, used as an adjunct to levodopa in PD patients who do not experience motor fluctuations, does not improve Unified Parkinson's Disease Rating Scale motor scores but does improve a variety of quality-of-life measures.  相似文献   
49.

Background  

Hypertension has been shown to start in early life and to track into adulthood. Detecting adolescents with hypertension and prehypertension will aid early intervention and reduce morbidity and mortality from the disorders. This study reports the point-prevalence of the two disorders in a semi-urban and an urban population of school-going adolescents in Nigeria.  相似文献   
50.
OBJECTIVE: To measure the efficacy of body mechanics instruction (BMI) in patients with low back pain. METHOD: The effect of BMI was measured in four participants with back injuries using a standardized lifting protocol. Static strength, weight lifted, number of lifts completed, and motion analysis data to describe the body mechanics were measured before and after work hardening to evaluate treatment effects. The participants' performances were compared with 52 controls from an earlier study. RESULTS: Starting postures, characterized by degrees of hip and knee flexion, varied by participant but favored a squat lift in three participants when compared with the controls. Dynamic motion synchrony of the hip and knee joints was similar to controls in three of the four participants. Posttest data revealed significant changes in static strength, dynamic endurance, and lifting speed. CONCLUSION: Intensive instruction in body mechanics provided during the work-hardening treatment produced major changes in lifting styles, in terms of both starting postures and dynamic aspects of repetitive lifting. The computerized measurement procedures used in this study permitted more careful and detailed analyses of body mechanics, particularly dynamic aspects, than is possible with observational methods. This study demonstrated some of the inherent intricacies in isodynamic lifting and suggests additional areas of performance that may be important to address in BMI.  相似文献   
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