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201.
G. N. Raval L. J. Parekh D. D. Patel F. P. Jha R. N. Sainger P. S. Patel 《Indian journal of clinical biochemistry : IJCB》2004,19(2):60-71
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
202.
S. Biswas A. Bhelwa A. Itoop S. Biswal N. Nath 《Indian journal of clinical biochemistry : IJCB》1994,9(1):9-12
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
203.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP. 相似文献
204.
Jay N. Zemel 《Journal of The Franklin Institute》1973,296(6):475-483
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
205.
T. Malati G. Rajani Kumari P. V. L. N. Murthy Ch. Ram Reddy B. Surya Prakash 《Indian journal of clinical biochemistry : IJCB》2006,21(1):34-40
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
206.
Chandrawati Kumari Bijo Varughese Siddarth Ramji Seema Kapoor 《Indian journal of clinical biochemistry : IJCB》2016,31(4):414-422
Pre analytical process of extraction for accurate detection of organic acids is a crucial step in diagnosis of organic acidemias by GCMS analysis. This process is accomplished either by solid phase extraction (SPE) or by liquid–liquid extraction (LLE). Both extraction procedures are used in different metabolic laboratories all over the world. In this study we compared these two extraction procedures in respect of precision, accuracy, percent recovery of metabolites, number of metabolites isolated, time and cost in a resource constraint setup. We observed that the mean recovery from SPE was 84.1 % and by LLE it was 77.4 % (p value <0.05). Moreover, the average number of metabolites isolated by SPE and LLE was 161.8 ± 18.6 and 140.1 ± 20.4 respectively. The processing cost of LLE was economical. In a cost constraint setting using LLE may be the practical option if used for organic acid analysis. 相似文献
207.
C.S. Badue R. Baeza-Yates B. Ribeiro-Neto A. Ziviani N. Ziviani 《Information processing & management》2007
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
208.
Sameer Hinduja 《Ethics and Information Technology》2007,9(3):187-204
Accompanying the explosive growth of information technology is the increasing frequency of antisocial and criminal behavior
on the Internet. Online software piracy is one such behavior, and this study approaches the phenomenon through the theoretical
framework of neutralization theory. The suitability and applicability of nine techniques of neutralization in determining
the act is tested via logistic regression analyses on cross-sectional data collected from a sample of university students
in the United States. Generally speaking, neutralization was found to be weakly related to experience with online software
piracy; other elements which appear more salient are suggested and discussed in conclusion. 相似文献
209.
210.
Diego Reforgiato Recupero 《Information Retrieval》2007,10(6):563-579
Text document clustering provides an effective and intuitive navigation mechanism to organize a large amount of retrieval
results by grouping documents in a small number of meaningful classes. Many well-known methods of text clustering make use
of a long list of words as vector space which is often unsatisfactory for a couple of reasons: first, it keeps the dimensionality
of the data very high, and second, it ignores important relationships between terms like synonyms or antonyms. Our unsupervised
method solves both problems by using ANNIE and WordNet lexical categories and WordNet ontology in order to create a well structured
document vector space whose low dimensionality allows common clustering algorithms to perform well. For the clustering step
we have chosen the bisecting k-means and the Multipole tree, a modified version of the Antipole tree data structure for, respectively, their accuracy and
speed.
相似文献
Diego Reforgiato RecuperoEmail: |