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1.
低价林早期诊断: 生态因子途径   总被引:3,自引:2,他引:1  
提出了低价林早期诊断的新思路,即根据低价林的形成规律,在林分还未表现出低价林状况时就能诊断出其发展趋势,以便及时采取相应的经营管理措施,以辽西油松林为例,从生态因子途径开展了低价林的早期诊断研究,建立了基于单因素实验和判别分析的生态因子途径早期诊断技术。研究表明,土层厚度X1,有机质含量X2,土壤全氮含量X3,土壤含水率X4,土壤微生物总数量X5可选择作为油松低价林早期诊断的敏感指标;在综合诊断时引入了判别分析的数量分类方法,并根据判别分析的思路建立了油松林生长状况生态因子途径早期诊断方法,其步骤:1)确定判别指标;2)建立判别函数Y=1.596X1-0.51X2-3.196X3+1.622X4+1.898X5;3)通过判别函数和研究对象的各项判别指标值进行早期诊断低价林早期诊断的技术与方法尚有待进一步地研究,检验和完善。  相似文献   

2.
Mating system and reproductive skew in the black rhinoceros   总被引:5,自引:0,他引:5  
Only approximately 2600 black rhinoceros survive today, mainly in small, isolated populations of < 100 animals. The management of remaining black rhinoceros populations aims at preserving natural levels of genetic relatedness and optimizing breeding success, which requires an accurate knowledge of the mating system, reproductive skew and effective population size. DNA was extracted from faecal samples from a community of 35 wild black rhinoceros, and microsatellites were used to characterize patterns of paternity of 19 offspring born from eight females in this community. Paternity could be ascribed unequivocally for each offspring. Although our conclusions must be considered tentative, we present the first genetic evidence that black rhinoceros males are polygynous, with a high variance in reproductive success. We also describe a noninvasive management tool that can be used for the genetic management of this critically endangered species, both in the wild and in captivity.  相似文献   

3.
The incidence of cancer has increased in recent years, especially in those over 65 years of age, posing a major health problem. Many tumours have a poor prognosis because they are diagnosed at very advanced stages. It is therefore especially important to incorporate liquid biopsy into clinical practice as a method for detecting tumours at very early stages. A systematic review was conducted, with the main objective of analysing the available literature on the use of liquid biopsy in the early diagnosis of cancer, and as a secondary objective, to determine the types of tumours that can be diagnosed early by liquid biopsy and the available biomarkers. The results indicate a lack of agreement with the biomarkers detected and the technologies applied. This highlights the need for multicentre studies to look at large cohorts and to establish protocols of action, as well as to increase analytical validity and the possibility of using a screening test for each type of tumour. This could be a very important step forward, as it could improve the management of cancer patients to a great extent.  相似文献   

4.
5.
OBJECTIVE--To examine the extent to which management of invasive breast cancer reflected consensus guidelines in the Thames regions in 1990. DESIGN--Population based study of case notes. SETTING--Thames Cancer Registry. SUBJECTS--All women with breast cancer diagnosed in early 1990 (417 cases) resident in the four Thames regions. Hospital records were traced for 346 cases, of which 12 were ineligible because of misclassification in initial registration and were excluded from the analysis. 334 cases were analysed. MAIN OUTCOME MEASURES--Investigations and treatment in the six months after diagnosis, stage of disease. RESULTS--Of the 334 women identified, 86 were aged under 50. Three years after diagnosis, 74 were dead, seven (8%) aged under 50 and 67 (27%) aged 50 or over. Axillary surgery was used to stage cancer in only 155 cases (46%), although this is recommended in the guidelines. Only 79 (24%) case notes had any information recorded on stage. Stage could be determined reliably for only half of the sample. Treatment varied widely within the same age group and stage of disease. In particular, chemotherapy was not routinely given to patients under 50 with stage II disease. Only 17 records showed evidence that the patient was participating in a clinical trial. CONCLUSIONS--There was a lack of consensus on the management of breast cancer among clinicians in 1990. More patients should be included in clinical trials.  相似文献   

6.
This paper describes the impact of a decision support system on the quality of recorded diagnoses and the completeness of medical records. The assumption is that for quality assessment purposes enough data have to be recorded in an electronic medical record so that diagnostic decisions can be justified. The hypotheses were tested that active decision support will lead to better quality recorded diagnoses and more complete medical records. Three groups of ten GPs were presented with 10 cases each. The GPs had to enter the data about these cases in a GP information system. One group of GPs was not supported. The second group was presented with the ICHPPC-II-Defined criteria that had to be fulfilled when a diagnosis was entered. In a third group, the GPs were asked those data that were needed to justify an entered diagnosis (active support). It could be shown that the last group of GPs entered better quality diagnoses than the other two groups. These latter groups also entered so little data that most of their diagnoses could not be justified. It is concluded from the study that only active decision support will lead to better diagnoses and a more complete medical record that can be used for quality assessment.  相似文献   

7.
The electrophoretic variation of blood proteins (hemoglobin, transferrin, adenylatekinase, and phosphoglucomutase) was studied in a population of 21 barbary sheep (Ammotragus lervia) living at Frankfurt Zoological Gardens. A polymorphism in hemoglobin was sufficient for pedigree analysis in most cases. It could be demonstrated that one female Barbary sheep cared for a lamb that genetically was not its own descendant. “Mismothering” has also been reported from domestic sheep. We suggest this to be critical when basing pedigree assumptions for stud-book purposes merely on behavioral evidence. Biochemical pedigree control is recommended for the genetic management of endangered social caprines during bottleneck phases of population recovery.  相似文献   

8.
A number of laboratory and field strains of Mycoplasma suipneumoniae and Mycoplasma flocculare were subjected to a comparative examination by the growth precipitation test. It was found that all the strains could readily be identified by that test. Slight evidence of cross-reaction was noted for a few of the laboratory strains, but not until late in the observation period. Only some of the field strains would form precipitates when primary cultures (from tissue suspensions) were used, but all strains could be identified already in the second and third passages. The test therefore seems well suited for distinguishing the two species from each other.  相似文献   

9.
发酵是科学技术,验证是科学的监督管理,技术离不开管理,管理也离不开技术,技术如果想飞得更稳,飞得更高,则必须插上科学管理的翅膀。介绍了验证的基础理论,将验证的理念融入到发酵技术中,建立发酵系统的验证思维,阐述了发酵系统验证由人员的确立、方案的制订、验证的实施到报告的总结的全过程。事实证明,建立发酵系统的验证是发酵过程中不可缺少的环节,也是执行GMP的要求,经过验证的发酵系统才是可靠的系统,经过验证的发酵工艺才是稳定的生产工艺。  相似文献   

10.
Swift PG 《Hormone research》2002,57(Z1):93-96
Management strategies and practicalities of insulin therapy in the first days and weeks after the diagnosis of diabetes in children and adolescents depend on the clinical situation and the facilities available. Outpatient or domiciliary management favoured by some centres is only practicable and safe if an experienced team is readily available. There is evidence showing a correlation between the level of glycaemic control achieved in the earliest years of treatment and the metabolic control in subsequent years (the 'tracking phenomenon'). The major factors influencing metabolic control in the first year after diagnosis certainly include the continuing secretion of endogenous pancreatic insulin. There has been considerable debate as to whether continuing insulin secretion and the induction of the remission phase can be significantly affected by the methods of insulin administration in the first days after clinical diagnosis; whether intravenous insulin has a protective effect; whether psychosocial factors have a more profound influence on metabolic control; and whether there is enough evidence to make valid recommendations on the optimal method(s) for treating children at the onset of diabetes. It seems likely that from the first day after diagnosis benefit is derived from attempting to obtain near normoglycaemia and the rapid induction of a partial remission phase by whatever insulin regimen is found to be most successful. This may occur not only by reducing the threat of glucotoxicity on the beta-cells but also by setting a pattern of optimal control for the child and the family. This process is enhanced by frequent contact with the team of experts in childhood diabetes who are able to give advice on insulin adjustments from the onset of diabetes.  相似文献   

11.
Role of fine needle aspiration cytology in diagnosis of pleomorphic adenomas This retrospective study was carried out to review the cases diagnosed as pleomorphic adenoma in major or minor salivary glands and determine the difficulties encountered on typing this tumour on fine needle aspiration cytology (FNAC). Over a 19‐year period (1982–2000) 488 pleomorphic adenomas were diagnosed on FNAC from different sites (parotid – 372 cases, submandibular – 95 cases; oral cavity – 21 cases). Histology was available in 232 cases. Twenty‐nine cases where a histological diagnosis of pleomorphic adenoma was made but the cytological diagnosis was variable were also reviewed. In 216 of the 232 cases a good cytohistological correlation was available. On review only 4 of the 16 cases initially diagnosed as pleomorphic adenoma on FNAC where the histology revealed a different tumour were categorized as pleomorphic adenoma, while 3 each were classified as adenoid cystic carcinoma and benign tumour ?type, and 2 each were diagnosed to be muco‐epidermoid carcinoma, monomorphic adenoma and acinic cell carcinoma. On review of the FNAC smears from 29 cases where a histological diagnosis of pleomorphic adenoma was available while the cytological diagnosis was variable, only 11 (38%) were categorized as pleomorphic adenoma. In the majority of the remaining cases the cytological diagnosis did not alter markedly, 7 of 10 cases where the tumour could not be typed on cytology initially could not be typed even on review. In conclusion, FNAC is an ideal, fairly accurate preoperative procedure for the diagnosis of pleomorphic adenomas. Certain diagnostic problems occur in differentiating pleomorphic adenomas from adenoid cystic carcinoma, monomorphic adenoma and mucoepidermoid carcinoma. Carcinoma ex‐pleomorphic adenoma is difficult to identify on FNAC and in our series all 4 such cases on histology were considered benign on cytology.  相似文献   

12.
The present document is the result of a consensus reached by a panel of experts from European and non-European countries on Occupational Rhinitis (OR), a disease of emerging relevance which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored on that of occupational asthma, as well as a diagnostic algorithm based on steps allowing for different levels of diagnostic evidence are proposed. The needs for future research are pointed out. Key messages are issued for each item.  相似文献   

13.
Objective Although practice guidelines for depression screening are evidence based, with their development relying on reviews of controlled studies, their adaptation and use as quality indicators have not been subject to rigorous study. This paper will therefore review the evidence supporting this practice.Methods A rational evaluation was carried out on both controlled studies and other sources of evidence related to the technical, clinical and policy assumptions underlying the use of depression screening guidelines as quality indicators.Results 1) Technical assumptions: depression screening could be used as a quality indicator. Current information technology does not allow accurate determination of who would benefit from being screened, whether they actually were screened, or the optimal percentage that should be screened. 2) Clinical assumptions: depression screening would improve outcomes. The evidence suggests that although depression screening might increase the diagnosis of depression, depressed patients so recognised tend to be less ill, less in need of treatment, or less likely to benefit from treatment, while screening, in the absence of other interventions, does not improve outcomes. 3) Policy assumptions: depression screening should be a focus of quality improvement. However, relative to other preventative measures, depression screening is a low priority. It does not meet usual cost-effectiveness criteria. There are more robust interventions for depression (i.e. collaborative care) that could be a focus of quality improvement efforts.Conclusion Although routine depression screening may be an acceptable practice guideline, its use as a quality measure is not supported.  相似文献   

14.
Twenty general practitioners co-operated in a study of the decision-making process in general practice respiratory illness. Ten simulated standard-patient consultations were used, each being included twice, once to make a decision on diagnosis and once to make a decision on management.Comparison of simulated behaviour with previous studies of observed and self-recorded behaviour showed encouraging agreement. Examination of 200 pairs of management and treatment decisions showed that fewer pieces of information were required for a management than a diagnostic decision on 111 occasions; in 43 pairs the quantity required was the same for each decision. The exact information required to make a decision on diagnosis was included in the information required to decide management on only 30 (15%) of the 200 possible occasions.When disagreement was found over management of a simulated case a decision to prescribe an antibiotic required less information than a decision not to prescribe an antibiotic.  相似文献   

15.
Not all non‐native species have strong negative impacts on native species. It is desirable to assess whether a non‐native species will have a negative impact at an early stage in the invasion process, when management options such as eradication are still available. Although it may be difficult to detect early impacts of non‐native species, it is necessary to ensure that management decisions can be based on case‐specific scientific evidence. We assess the impacts of a non‐native bird, the Black‐headed Weaver Ploceus melanocephalus, at an early stage in its invasion of the Iberian Peninsula. To do this we identify potential pathways by which competition for shared resources by Black‐headed Weavers could lead to population declines in two ecologically similar native species, and generate hypotheses to test for evidence of competition along these pathways. Black‐headed Weavers could potentially impact native species by displacing them from nesting habitat, or by reducing habitat quality. We found no evidence for either potential competition pathway, suggesting that Black‐headed Weavers do not currently compete with the two native species. However, it is possible that mechanisms that currently allow coexistence may not operate once Black‐headed Weavers reach higher population densities or different habitats.  相似文献   

16.
BACKGROUND: Metanephric adenoma (MA) is a relatively rare neoplasm derived from metanephric blastema and composed of well-differentiated epithelial nephroblastic cells. In view of its invariably benign clinical outcome, a preoperative diagnosis of this tumor could be of critical importance. Since computed tomography and ultrasound imaging are not per se sufficient to unequivocally distinguish between MA and malignant neoplasms, fine needle aspiration cytology (FNAC) could be the only accurate method to establish a preoperative diagnosis of this tumor. However, cytologic appearance of MA is not well characterized. CASE: A 33-year-old pregnant woman presented with erythrocytosis. Transabdominal ultrasound examination disclosed a mass in her left kidney. FNA smears showed small, uniform cells with bland nuclei arranged in compact acinar and follicular structures; immunocytochemical staining revealed a diffuse, positive reaction for CD57, WT-1 and vimentin, and epithelial membrane antigen and alpha-methylacyl-CoA racemase yielded negative results. These cytologic and immunocytochemicalfindings led to a preoperative diagnosis of MA. After delivery, the diagnosis was confirmed on the surgical specimen. CONCLUSION: A diagnosis of MA could be established by FNAC supported by immunocytochemical analysis. The present case illustrates the clinical impact that this diagnosis could have on patient management.  相似文献   

17.

Background

Prostate cancer (PCa) is the most common non-skin cancer among men in developed countries. Several novel treatments have been adopted by healthcare systems to manage PCa. Most of the observational studies and randomized trials on PCa have concurrently evaluated fewer treatments over short follow-up. Further, preceding decision analytic models on PCa management have not evaluated various contemporary management options. Therefore, a contemporary decision analytic model was necessary to address limitations to the literature by synthesizing the evidence on novel treatments thereby forecasting short and long-term clinical outcomes.

Objectives

To develop and validate a Markov Monte Carlo model for the contemporary clinical management of PCa, and to assess the clinical burden of the disease from diagnosis to end-of-life.

Methods

A Markov Monte Carlo model was developed to simulate the management of PCa in men 65 years and older from diagnosis to end-of-life. Health states modeled were: risk at diagnosis, active surveillance, active treatment, PCa recurrence, PCa recurrence free, metastatic castrate resistant prostate cancer, overall and PCa death. Treatment trajectories were based on state transition probabilities derived from the literature. Validation and sensitivity analyses assessed the accuracy and robustness of model predicted outcomes.

Results

Validation indicated model predicted rates were comparable to observed rates in the published literature. The simulated distribution of clinical outcomes for the base case was consistent with sensitivity analyses. Predicted rate of clinical outcomes and mortality varied across risk groups. Life expectancy and health adjusted life expectancy predicted for the simulated cohort was 20.9 years (95%CI 20.5–21.3) and 18.2 years (95% CI 17.9–18.5), respectively.

Conclusion

Study findings indicated contemporary management strategies improved survival and quality of life in patients with PCa. This model could be used to compare long-term outcomes and life expectancy conferred of PCa management paradigms.  相似文献   

18.
A rule-based, weight-of-evidence approach for assessing contaminated sediment on a site-by-site basis in the Laurentian Great Lakes is described. Information from four lines of evidence—surficial sediment chemistry, laboratory toxicity, invertebrate community structure and invertebrate tissue biomagnification—is integrated within each line to produce a pass (‘?’) or fail (‘+’) conclusion, then combined across lines resulting in one of 16 outcome scenarios. For each scenario, the current status of the site, interpretation, and management recommendations are given. Management recommendation(s) can range from no action to risk management required (9 of the 16 scenarios). Within each line of evidence, the strength of each response can also be ranked (e.g., score of 1 to 4), providing managers with more information to aid decision options. Other issues that influence scientific management recommendations include site stability, subsurface contamination and spatial extent of effects. The decision framework is intended to be transparent, comprehensive (incorporating exposure, effect, weight-of-evidence, and risk), and minimally uncertain.  相似文献   

19.
《Endocrine practice》2021,27(3):261-268
ObjectiveContextualizing the evaluation of older adults with thyroid nodules is necessary to fully understand which management strategy is the most appropriate. Our goal was to summarize available clinical evidence to provide guidance in the care of older adults with thyroid nodules and highlight special considerations for thyroid nodule evaluation and management in this population.MethodsWe conducted a literature search of PubMed and Ovid MEDLINE from January 2000 to November 2020 to identify relevant peer-reviewed articles published in English. References from the included articles as well as articles identified by the authors were also reviewed.ResultsThe prevalence of thyroid nodules increases with age. Although thyroid nodules in older adults have a lower risk of malignancy, identified cancers are more likely to be of high-risk histology. The goals of thyroid nodule evaluation and the tools used for diagnosis are similar for older and younger patients with thyroid nodules. However, limited evidence exists regarding thyroid nodule evaluation and management to guide personalized decision making in the geriatric population.ConclusionConsidering patient context is significant in the diagnosis and management of thyroid nodules in older adults. When making management decisions in this population, it is essential to carefully weigh the risks and benefits of thyroid nodule diagnosis and treatment, in view of older adults’ higher prevalence of high-risk thyroid cancer as well as increased risk for multimorbidity, functional and cognitive decline, and treatment complications.  相似文献   

20.
Antimicrobial drugs may be used to treat diarrheal illness in companion animals. It is important to monitor antimicrobial use to better understand trends and patterns in antimicrobial resistance. There is no monitoring of antimicrobial use in companion animals in Canada. To explore how the use of electronic medical records could contribute to the ongoing, systematic collection of antimicrobial use data in companion animals, anonymized electronic medical records were extracted from 12 participating companion animal practices and warehoused at the University of Calgary. We used the pre-diagnostic, clinical features of diarrhea as the case definition in this study. Using text-mining technologies, cases of diarrhea were described by each of the following variables: diagnostic laboratory tests performed, the etiological diagnosis and antimicrobial therapies. The ability of the text miner to accurately describe the cases for each of the variables was evaluated. It could not reliably classify cases in terms of diagnostic tests or etiological diagnosis; a manual review of a random sample of 500 diarrhea cases determined that 88/500 (17.6%) of the target cases underwent diagnostic testing of which 36/88 (40.9%) had an etiological diagnosis. Text mining, compared to a human reviewer, could accurately identify cases that had been treated with antimicrobials with high sensitivity (92%, 95% confidence interval, 88.1%–95.4%) and specificity (85%, 95% confidence interval, 80.2%–89.1%). Overall, 7400/15,928 (46.5%) of pets presenting with diarrhea were treated with antimicrobials. Some temporal trends and patterns of the antimicrobial use are described. The results from this study suggest that informatics and the electronic medical records could be useful for monitoring trends in antimicrobial use.  相似文献   

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