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971.
K. S. S. Saibaba P. V. L. N. Srinivasa Rao K. V. Dakshina Murty M. Vijaya Bhaskar 《Indian journal of clinical biochemistry : IJCB》1997,12(2):139-141
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
972.
J. Baxi Kavita Sharma Rajbala Asha Mehta A. K. Pendse P. P. Singh 《Indian journal of clinical biochemistry : IJCB》1994,9(1):47-49
Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one. 相似文献
973.
Scott Janzwood 《Research Policy》2021,50(6):104225
"Mission-oriented" public research organizations invest in R&D to improve decision-making around complex policy problems from climate change to asteroid impacts, thus producing public value. However, the estimation of benefits produced by such R&D projects is notoriously difficult to predict and measure - a challenge that is magnified for global catastrophic risks (GCRs). GCRs are highly uncertain risks that may pose enormous negative consequences for humanity. This article explores how public research organizations systematically reduce key uncertainties associated with GCRs. Building off of recent literature highlighting the organizational and political factors that influence R&D priority-setting at public research organizations, this article develops an analytical framework for explaining R&D priority-setting outcomes that integrates the key stages of decision analysis with organizational and political dynamics identified in the literature. This framework is then illustrated with a case study of the NASA Planetary Defense Coordination Office, which addresses the GCR of near-Earth object (asteroid and comet) impacts. The case study reveals how organizational and political factors interact with every stage in the R&D priority-setting process - from initial problem definition to project selection. Lastly, the article discusses the extent to which the case study can inform R&D priority-setting at other public organizations, particularly those addressing GCRs. 相似文献
974.
Lakshmi Krishnamoorthy Elizabeth Zachariah P. G. Ramaswamy N. Anantha 《Indian journal of clinical biochemistry : IJCB》1994,9(1):37-39
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
975.
J. I. Anetor F I Ajose T. S Akingbola 《Indian journal of clinical biochemistry : IJCB》2005,20(1):193-197
A 64-year-old security guard and longstanding known hypertensive presented with hypertensive heart disease (HHD), weight loss,
an enlarged prostate, and a spontaneously fractured rib. Malignancy of the prostate with possible metastases to the ribs was
strongly suspected. Biochemical profiling revealed a paraprotein. Other biochemical and hematological correlates that were
on hand before serum protein electrophoresis were rather atypical. Paraprotein studies by immunofixation revealed IgA myelomatosis.
Unlike previous reports from Caucasians there was normocalcaemia, normal protein level, microcytic hypochromia, low MCHC,
cholesterol level at the lower limit of the reference range and normal urea level (in the face of markedly raised creatinine
level). Nutritional modulation of the classical laboratory features of this disease may account for the fairly atypical laboratory
picture.
The need to appreciate the influence of nutritional status on the laboratory (especially biochemical) features of a disease
and thus interpretation of diagnostic tests appears of exceptional current importance, given the widening gap in socioeconomic
status and the level of poverty between the resource poor and developed countries from which the classical, clinical and laboratory
features of most diseases were first described.
This case report reminds of the need not only to recognize theoretically the impact of nutritional status on the laboratory
characteristics of a disease but of the practical application of the nutritional perspective in the interpretation of diagnostic
investigations, especially in nutritionally disadvantaged communities. 相似文献
976.
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
977.
The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with
those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the
fertile men was 40.7±5.2 mIU/106 sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/106 sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of
the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/106 sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased
morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly
lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa. 相似文献
978.
979.
Robert J.P. Williams 《Endeavour》1984,8(2):65-70
Zinc is as common as iron in biology. It is usually thought to be a trace element required only for catalysis. Here it is shown that the role of zinc is much more fundamental not only in catalysis but in inhibitory control. There may well be several such control elements—calcium, iron, manganese, magnesium, and zinc. 相似文献
980.