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501.
The adoption of e-governing practices has revolutionised the administrative machinery of governments worldwide by improving efficiency, transparency, and accountability. Researchers and administrators often aim to identify emerging research fronts and the timeline of the evolution to forecast and implement technology. In this work, we systematically investigate the trajectory of the global evolution and emerging research fronts as well as the prospects for e-governance using citation network analysis. The growth curve fitted to the number of articles published per year shows that the research activities are still in the ascendant phase. We visualise the global main path of the citation network and investigate the patterns to trace the knowledge diffusion path, major milestones, and emerging research fronts. The cluster analysis identifies the major topics of research as administration and information system management, e-governance framework design, efficiency or quality evaluation, and the application of social networks and open data leading to e-democracy. The adoption of open data and social networking for user interactions with government that leads to participatory governance are the emerging research trends. We also identify research that can have a future impact based on network parameters. The results contribute to the literature by setting the focus of future research, and assisting administrators in selecting suitable models and methodologies, and manufacturers with the development of required technical devices suitable for the upcoming phase of symbiosis.  相似文献   
502.
Adenosine deaminase (ADA) and 5′-nucleotidase (5′-NT) activities were measured in sera of patients with ovarian cancer and patients with benign ovarian tumour. The results were compared with that of a control group consisting of healthy women. ADA levels were significantly increased (P<0.001) in the ovarian cancer group (n=50) but not in the benign group (n=28) when compared to the controls (n=20). The results indicate that ADA and 5′-NT levels may help to differentiate malignant conditions from benign tumours of the ovary in addition to the existing tests such as serum CA-125 levels and histopathological study.  相似文献   
503.
Effect of feeding ripe and unripe papaya fruit pulps were investigated on blood lipid profile of normal male adult albino rabbits by giving them pulps separately at the dose of 15 and 30g per day along with standard diet over a period of six weeks. As compared to controls both fruit pulps resulted in highly significant (p<0.001) and consistent lowering of serum cholesterol, low density lipoprotein cholesterol and triglycerides and elevation in phospholipids and high density lipoprotein cholesterol levels at 1,3 and 6 weeks of fruit pulp feeding indicating a dose dependent effect. Observations clearly support medicinal value ofC. Papaya in the management of atherosclerosis, fatty liver, ischaemic changes and consequential myocardial infarction.  相似文献   
504.
This study was carried out to estimate the levels of glutathione peroxidase and selenium in blood of abortion cases. Glutathione peroxidase and selenium were determined in 52 abortion cases (22 in 1st trimester, 30 in second trimester), 45 normal pregnant cases and 25 nonpregnant control cases. The selenium concentration in whole blood and plasma in abortion cases was almost the same as in normal pregnant women but significantly low when compared with the control non-pregnant group. The glutathione levels was higher in abortion cases when compared with normal pregnant and non-pregnant control groups. Red cell and plasma glutathione peroxidase activities of women who had abortion were significantly lower compared with both non-pregnant control group and normal pregnancies.  相似文献   
505.
506.
Tuberculosis is still a major health problem in most developing countries and its incidence is rising in many developed countries. This resurgence has been attributed to the HIV epidemic and TB has been declared as a global health emergency by WHO in 1993. The diagnosis of tuberculosis mainly depends upon initial clinical suspicion and radiographic findings with subsequent bacteriological confirmation by sputum smear examination and culture. Lack of sensitivity in smear examination, non specificity of radiological findings, extended tum around time ofMycobacterium tuberculosis culture and difficulties in diagnosing paucibacillary, childhood and extrapulmonary tuberculosis has necessitated to explore the utility of immunodiagnosis of tuberculosis as a convenient and cost effective test to supplement clinical information for definite diagnosis. Many commercial tests are available in the market for diagnosis of TB. Most of these tests are based on the detection of IgG, IgA and IgM antibodies to specific mycobacterial antigen or mixture of antigens. Indigenous immunoassay systems have explored excretory-secretory ES-31 mycobacterial antigen for immunodiagnosis of TB. Many a time there is lack of consistent elevation in all the three Ig classes in active infection thus making it more important to determine the ideal antibody isotype assay for reliable diagnosis of tuberculosis and to save the costs of the patient for unnecessary investigations.  相似文献   
507.
Serodiagnosis by ELISA has been widely explored over the years, in the diagnosis of tuberculosis. Two ELISA systems were evaluated for detection of mycobacterial antibodies in pulmonary and extra pulmonary tuberculosis. The two test assays explored were ERBA LISA (TB IgG) test (Anda Biologicals) which uses A60 antigen complex found in the cytosol of typical and atypical mycobacteria, and SEVA TB (IgG) ELISA, which uses a 31 kDa, glycoprotein antigen purified fromM. tb H37Ra culture filtrate. Sera from 98 proven tuberculosis [pulmonary TB (48), tuberculous lymphadenopathy (30), tuberculous meningitis (15) & genitourinary TB (5)] were studied along with 32 healthy controls. The overall positivity obtained using ERBA LISA (TB IgG) test and SEVA TB (IgG) ELISA test was 72.9% and 91.6% in pulmonary tuberculosis, 43.3% and 76.6% in tuberculous lymphadenopathy respectively. The sensitivity of ERBA LISA test in tuberculous meningitis and genito-urinary TB was significantly low (26.6% & 40% respectively) compared to sensitivity obtained using SEVA TB ELISA (86.6% & 60% respectively) with overall specificity of 60% and 87.5%. Thus SEVA TB IgG ELISA test was found to be more sensitive than ERBA LISA in detecting IgG antibodies in tuberculous sera, in particular in extra pulmonary tuberculosis cases.  相似文献   
508.
The normal coagulation process is initiated by disruption and exposure of the subendothelial components of blood vessels. Platelets adhere to subendothelium-bound von Willebrand factor via glycoprotein (GP) Ib complex. This initial interaction per se and the release of platelet agonists transduce signals that leads to the rise in intracellular Ca2+ which induces shape change, prostaglandin synthesis, release of granular contents and conformational changes in platelet Gp IIb-IIIa. Gp IIb-IIIa in activated platelets binds fibrinogen and other adhesive proteins and mediates platelet cohesion the primary haemostatic plug. Furthermore, the activated platelets due to aggregation, result in the formation of fibrin (secondary hemostasis). Normally the haemostatic process plays a delicate balance between keeping the blood in the fluid state to maintain flow and rapidly forming an occluding plug following vessel injury. Thrombosis occurs because of alteration in this delicate balance. Arterial thrombosis occurs in the setting of previous vessel wall injury mostly because of atherosclerosis, while venous thrombosis occurs in areas of stasis. The recent advances in understanding of the haemostatic process have led to a better understanding of the mechanism of action of many antithrombotic drugs and identification of new targets for drug development. The molecular target of the ticlopidine has been identified. Large numbers of IIb-IIIa inhibitors have been developed. The mechanism of action of heparin has been defined at the molecular level. As a result, a synthetic pentasaccharide, based on antithrombin-binding domain of heparin, has been developed and tested successfully in clinical trials. New generation direct thrombin inhibitors are being developed. Factor Xa has a critical position at the convergence of intrinsic and extrinsic pathway. The clinical tolerability and the efficacy of low molecular weight heparins has established that inhibition of further thrombin generation, by blocking factor Xa alone can be an effective way of preventing thrombus growth without inactivating thrombin. A large number of specific factor Xa inhibitors are under development. Some of these are in preliminary clinical trials and appear to be promising. Future clinical trials will determine whether these new drugs will provide better risk-benefit ratio in treatment of thrombotic disorders. Similarly role of thrombolytics has been clearly established in many diseases including coronary artery disease.  相似文献   
509.
The semiconductor industry operates in a constant state of deflation. It is vital to our survival and progress in this knowledge era. The industry is extremely competitive and requires ongoing technological advances to improve performance while reducing costs to remain competitive. Gaining an understanding of important facets of this industry is essential. Besides knowing about semiconductor history, other aspects of interest include types of semiconductor products in the marketplace and their uses, typical semiconductor-chip making process, overall industry review and trends. One critical tool used by the industry to direct product and technology development is a technology roadmap. Review of the initial and current semiconductor technology roadmap would further enhance our understanding of semiconductor industry.  相似文献   
510.
The chemical modifications that occur during vulcanization of rubber and methods for controlling the process are discussed.  相似文献   
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