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121.
This article serves as an introduction to log-linear analysis, a technique used in the analysis of qualitative data arranged in multidimensional contingency tables. The steps involved in log-linear analysis are presented in the context of an investigation of a personality characteristic of a group of counselor trainees. The references cited and supplemental readings allow interested readers to pursue the topic further.  相似文献   
122.
Selecting the correct method for routine analysis by ‘method evaluation’ is an important component of quality assurance. It is a step-wise procedure that evaluates various analytical parameters like accuracy, precision etc of the given method. Finally reference intervals are established for selected population. We evaluated an enzymatic method for serum creatinine. The results show that it is an acceptable method based on the above mentioned criteria.  相似文献   
123.
Circulating levels of gonadotropins (FSH,LH), prolactin (PRL), estradiol and progesterone were measured by radioimmunoassay in the sera of 60 patients with histopathologically proven breast cancer. 30 patients belonged to the post and 30 to the premenopausal group. 30 healthy women, 15 each in the pre and post menopausal groups served as controls for the study. Prolactin was elevated in 33% and 26% of pre and post menopausal breast cancer patients respectively. Lower levels of estradiol and progesterone were observed during the luteal phase of the menstrual cycle in premenopausal breast cancer patients. Among postmenopausal patients with breast cancer, LH was elevated in 32%, FSH in 15% and estradiol in 30% of the patients studied.  相似文献   
124.
Sialic acid, the end moieties of the carbohydrate chains are biologically important and essential for functions of glycoconjugates and are reported to be altered in cancer patients. Two hundred and twenty five breast cancer (BC) patients, 100 patients with benign breast disease (BBD) and 100 healthy females (controls) were enrolled for the study. Eight hundred and twenty four follow-up samples of 225 breast carcinoma patients were also evaluated. The association of sialic acid forms, sialyltransferase and α-2–6 sialoproteins levels with presence and extent as well as prognosis of breast carcinoma was studied. Serum sialic acid forms and sialyltransferase revealed significantly elevated levels among untreated breast cancer patients as compared to the controls, patients with BBD as well as cancer patients in remission. Non-responders showed comparable levels of the markers with those found in breast cancer patients at the time of diagnosis. Higher levels of sialic acid forms at diagnosis were associated with poor prognosis. A positive correlation between serum levels of different forms of sialic acids and extent of malignant disease was observed. The changes in serum proteins with terminal α-2–6 sialic acid correlated well with alterations in the levels of sialic acid forms and sialyltransferase. Malignant tissues showed elevated levels of sialic acid and sialyltransferase as compared to surrounding normal tissues. The results suggested potential utility of these markers in evaluation of clinical outcome.  相似文献   
125.
Membrane hydrophobicity and slalidase activity of normal Poly morphonuclear Leucocyte were significantly enhanced when incubated with DSF. As a consequence, internalisation ofE. coli andS. aureus (opsonised or unopsonised) were greatly dimnished, internalisation ofE. coli being higher in either category. Although, increase in hydrophobicity of the membrane correlated well with the time of decrease of particle internalisation (both at 30 min.), enhancement of sialidase activity did not coincide with the said alterations.  相似文献   
126.
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed.  相似文献   
127.
Several methods of detecting the presence of various chemical species are considered. A specific example of atomic hydrogen in lead selenide is examined and used to illustrate some important principles.  相似文献   
128.
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and 10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase (P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death.  相似文献   
129.
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community.  相似文献   
130.
李娜  刘洋  李玉乐  孙静 《编辑学报》2020,32(2):177-180
随着泛在网络时代的到来,新媒体已成为人们获取健康知识的首要途径;但当前网络健康知识来源芜杂,各种夸大甚至歪曲医学事实的报道层出不穷,健康科普的“含金量”亟须提高。临床医学期刊是权威医学成果发布和交流的重要平台,拥有由作者、审者和编者等众多优秀医学专业工作者组成的专家团队,具有天然的健康科普优势和媒体属性。《协和医学杂志》通过将医学论文科普化、捕捉新闻热点、培养科普人才、充分利用新媒体平台等途径,证明临床医学期刊有责任更有能力在健康科普中发挥重要作用。  相似文献   
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