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Summary.  Quercus × warburgii A. Camus, the Cambridge Oak, is a semi‐evergreen tree of hybrid origin, possibly between Q. rugosa Née and Q. robur L., and is only known in cultivation. Mature trees in gardens are extremely rare. Its history and cultivation are discussed.  相似文献   

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Summary.  The hybrid hazel, Corylus  ×  vilmorinii Rehder is described and illustrated. Its robust habit and showy catkins make it an interesting and worthwhile tree to cultivate.  相似文献   

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2021年5月24日—28日第十一届国际根系研究大会和第九届根系发育研讨会(Rooting2021)联席会议由美国密苏里州州立大学和英国汉诺丁大学共同组织并在线举办。本次大会主题为“探索根系:发现新前沿”,参加会议的有来自世界51个国家,主要包括:美国、英国,澳大利亚、中国以及来自南美、欧洲和非洲的部分国家,共计693人参会。本届根系大会研讨领域广泛,涉及根的宏观到微观不同尺度的研究。预计未来根系领域研究热点主要集中在:根系表型研究技术的研究、根系的生态系统服务功能、根系的逆境生理学研究、根系与土壤交互作用、根系与微生物互作的研究以及根和根系发育等。  相似文献   

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Summary.  Rosa 'Cantabrigiensis' is a hybrid whose history is connected with Cambridge University Botanic Garden where it was raised and first recognised in 1922. Its origin in the experimental work on Rosa by Charles Hurst is discussed, and its likely parentage is given.  相似文献   

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《Médecine Nucléaire》2023,47(3):120-130
Bone scintigraphy is a nuclear imaging scan using a radiopharmaceutical composed of a bisphosphonate coupled to a radionuclide (technetium 99 m). Radiopharmaceutical uptake is particularly important at the level of the bone structures having a strong osteoblastic activity. These uptakes can be due to a benign pathology (fracture, loosening of prosthesis, rheumatic pathologies, etc.) or to a malignant pathology (primary or secondary bone lesion). The high sensitivity of bone scintigraphy makes it particularly interesting at the initial stage of the pathology, especially when x-rays are normal. In addition, its specificity has clearly improved in recent years with the increasingly use of tomoscintigraphy coupled with X-ray scanning (SPECT/CT). We describe the operating principle of bone scintigraphy, normal uptakes with its variants as well as pathological uptake features in traumatic, rheumatic, prosthetic or cancerous pathologies.  相似文献   

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Human papillomaviruses and Chlamydia trachomatis are two of the most commonly found sexually transmitted infections in cervical Pap smears. They are often asymptomatic and if left untreated can progress to cause serious complications such as pre-cancerous lesions and tubal factor infertility, respectively. The aim of this study was to develop a rapid multiplex PCR for the simultaneous detection of HPV and C. trachomatis in ThinPrep® liquid cytology samples. Two multiplexes were optimized. (A) For the detection of C. trachomatis using primers for the cryptic plasmid and for a chromosomal gene ( Hsp60 ); (B) for the simultaneous detection of HPV and C. trachomatis using consensus primers for HPV and plasmid primers for C. trachomatis . Both multiplexes included a set of primers for a human housekeeping gene- β -globin. DNA from 34 ThinPrep® cervical samples was extracted using the QiAmp DNA Mini Kit (Qiagen Ltd, UK). All 34 samples were previously confirmed positive for C. trachomatis using another nucleic-acid based test. Using multiplex A.for the detection of C. trachomatis , 33 of 34 samples were positive for C. trachomatis by either the plasmid or chromosomal gene primer set. All samples were positive for β -globin. Ten of the 34 C. trachomatis positive samples were known positives for HPV. Using the combined HPV and C. trachomatis multiplex 10 of 10 were positive for both HPV and C. trachomatis . These simple multiplexes are cost-effective, rapid and have potential for rapid screening of cervical ThinPrep samples simultaneously for both HPV and C. trachomatis .  相似文献   

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The past decades have seen an explosion in our knowledge of the molecular events underpinning the pathogenesis of many disease processes. Furthermore, there have been enormous technical advances with the ability to identify, clone and sequence genes and to characterize their protein products now being common place in research settings. However, despite many claims as to the utility of molecular and biochemical methods in pathology only very few laboratories employ such methods in a clinical setting. Indeed the impact of molecular medicine has been more talked about than real. Why is this? The goal of this presentation is to address this question and present some perspectives on the future of Molecular Pathology. I shall overview, for the BSCC, the current state of the technology available for gene analysis and to explore the developments needed before the mirage of molecular pathology becomes a clinical reality.  相似文献   

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Background  ERCP-directed brush cytology is used to sample lesions of the pancreatic and biliary ducts and the ampulla of Vater. With conventional preparations, the sensitivity and specificity range from 44% to 63% and 80% to 98%, respectively, and increased N : C ratio, nuclear molding and loss of honeycombing are reliable features of malignancy. The performance and morphology of specimens prepared by ThinPrep, a liquid-based cytology technique is mostly unknown.
Methods  The laboratory information system was searched for all cases prepared by ThinPrep. Patient disease classification of benign or malignant was determined by linkage with the provincial cancer registry and was the gold standard against which sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. True positives and negatives were reviewed to identify predictive cytomorphologic features.
Results  Between 1996 and 2001, there were 149 ThinPrep specimens; 55 (37%) were reported as positive for malignancy and 94 (63%) as negative. Disease was classified as malignant in 86 (58%) patients and benign in 63 (42%). There were 42 false negative, 11 false positive, 52 true negative, and 44 true positive cytology results. Sensitivity was 51.2% (CI; 40.2 : 62.0), specificity 82.5% (CI; 70.5 : 90.6), and PPV and NPV 80.0% (CI; 66.6 : 89) and 55.3% (CI; 44.7 : 65.5), respectively. Cell groups with crowded, enlarged, irregular nuclei and nuclear features of vesicular chromatin and large, multiple irregular nucleoli correlated with malignant disease, while monolayered sheets of uniform columnar cells, regular nuclei and a finely granular chromatin correlated with benign disease.
Conclusions  The performance of ThinPrep brushings from this anatomic site equals conventional preparations. Cytomorphologic features of malignancy are more frequent and pronounced with ThinPrep.  相似文献   

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The success of the Cervical Screening Programme (CSP) is due in part to its management being underpinned by Quality Assurance. These measures ensure uniform standards across the country. Since 1992 Colposcopy Guidelines have been in place; these were updated in 1997 and have just been redefined. It is entirely consistent with the National CSP that colposcopy is governed by Guidelines.
The aim of clinical practice guidelines is to raise the standard of care and improve outcomes. The objectives are, therefore:

    The credibility of guidelines is crucial to their adoption and this depends far more on the demonstration of an evidence base than that the authors are 'experts'. Development by a professional group or body who are seen as having a legitimate role is very important as is involvement of all 'stakeholders' in ensuring acceptability.
    In terms of their nature, guidelines should be valid i.e. they will achieve what they are intended to achieve, and they should be robust i.e. they will work when implemented by different individuals in different settings. Colposcopy lends itself well to guidelines because it is largely a routine practice, but substandard care can have serious consequences.
    In previous years there has been a set of Guidelines for Practice 1, 2 and a set of Quality Standards 3 . On this occasion these two components have been put together in a simple publication.
    It needs to be borne in mine that the new guidelines were being developed in the context of a number of potential changes which could interact with each other and impact on the Guidelines. These include:
     
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    Introduction  Colposcopy Quality Standards state that more than 85% of excisional biopsies should show CIN 1 or worse. Data from the National KC65 reports show a large difference between units (50% to 100%). This study investigates the reasons for failure to meet the standard.
    Methods  A review of 1158 consecutive new and 1043 follow-up colposcopy examinations from a colposcopy database in East Somerset. Patients were treated at the time of initial examination if there was a clinically significant lesion, or at follow-up depending on the results of investigations.
    Results  Only 59% of excisional biopsies showed CIN 1 or worse. The possible reasons for failure to meet the standard were explored. Possible explanations explored are erroneous colposcopy, false negative histology, and false positive cytology. The cytology–histology correlation was compared between excisional and directed biopsies, and between the two local cytology screening departments.
    Conclusions  The collection of meaningful national data has more to do with careful definition than clinical practice or data collection.  相似文献   

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    Both the original Bethesda system and the current UK classifications of cervical cytology have proved robust but each has a major weakness in the area of abnormalities of uncertain significance. Cytologists recognize that sometimes it is simply impossible to differentiate between reactive and dyskaryotic material. For this reason, the Australian version of the Bethesda system introduced a new category of 'high grade inconclusive' with a recommendation for referral to colposcopy. Approximately 60% of such cases are found to have high grade lesions at colposcopy (Schoolland M, Sterrett G, Knowles S et al .). The present UK system even with the proposed changes requires of the pathologist, a decision as to whether such cases are probably high grade (=a report of moderate dyskaryosis) or not (= a report of borderline). This continues to ignore the fact that sometimes you just cannot tell, even on review. We have taken a consecutive series of 50 referral smears, reported as moderate dyskaryosis, where the histological outcome (by loop cone) is known. These cases were rescreened and then reviewed blind by a pathologist with extensive experience of the Australian NH & MRC modified Bethesda system. On review, the material was reclassified along NH & MRC lines. The results were compared with the biopsy findings in order to determine whether the category of 'inconclusive' might be of value in the context of the NHSCSP.  相似文献   

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    Multiple sclerosis (MS) is considered an autoimmune demyelinating disease of the CNS and myelin‐derived glycolipids are one of the targets of this autoimmune attack. In this study, we examined for the first time the plasma distribution of sulfatide isoforms. Sulfatides with long‐chain (C24 : 0 or C24 : 1) and short‐chain (C16 : 0 or C18 : 0) fatty acids were quantified in plasma of relapsing–remitting MS patients by ultra‐high‐performance liquid chromatography tandem mass spectrometry. We found that C18 : 0 and C24 : 1 sulfatide plasma levels positively correlated with the Expanded Disability Status Scale. C16/C18 : 0 and C16/C24 : 0 ratios also correlated with the age and the time since last relapse. Healthy women showed higher levels of C16 : 0 sulfatide than healthy men; however, this gender difference disappeared in MS patients. Our data underline the potential use of sulfatides as biomarkers in relapsing–remitting MS and points to a possible association with the higher susceptibility of women to develop MS.

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