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171.
Murali Krishna Madisetty Konda Kumaraswami Shivakrishna Katkam Kankanala Saumya Y. Satyanarayana Raju Naval Chandra Maddury Jyotsna Sujatha Patnaik Vijay Kumar Kutala 《Indian journal of clinical biochemistry : IJCB》2016,31(3):278-285
We aimed to assess whether measuring carotid intima-media thickness (CIMT) and oxidative stress markers such as protein carbonyls, malondialdehyde, nitrate and glutathione in plasma of elderly patients without and with coronary artery disease (CAD) identifies early risk for CAD. A total of 50 cases with cardiovascular risk factors over the age of 60 years without CAD, and 50 patients with angiographically documented CAD over the age of 60 years were included in the study. Control group consists of 200 healthy individuals without the risk factors. Demographic details were obtained from all the subjects and CIMT measured by high frequency ultrasound and oxidative stress markers such protein carbonyls, malondialdehyde and total glutathione were determined in plasma by spectrophotometric methods. The distribution of cardiovascular risk factors in without CAD and CAD cases were smokers (16 vs 56 %), hypertension (26 vs 64 %), diabetes (16 vs 56 %) and dyslipidemia (18 vs 58 %) and positive family history (4 vs 38 %). None of the control group had any cardiovascular risk factors. Among the CAD cases, 16 % had single vessel disease, 44 % had double vessel disease and 40 % had triple vessel disease. The CIMT was significantly increased in CAD cases as compared to cases without CAD and healthy controls. On the other hand, CIMT was significantly increased in cases without CAD as compared to healthy controls. CIMT also increased with the duration of diabetes in patients without CAD and severity of disease in CAD cases. The levels of oxidants like plasma malondialdehyde, protein carbonyls, were significantly elevated and antioxidant glutathione levels and nitrate levels were significantly reduced in cases with and without CAD as compared to healthy controls. Oxidative stress markers and CIMT was found to be significantly increased in patients with cardiovascular risk factors like diabetes, family history of CAD, dyslipidemia, hypertension and smoking when compared to patients without risk factors. In patients with diabetes, CIMT increased as duration of disease increases and also in poorly controlled diabetes. In CAD group, when number of vessel involvement (severity of coronary disease) increases, the CIMT also increases confirming that CIMT is a quantifiable risk factor for CAD. 相似文献
172.
Ranjana Singh Rajesh K. Singh Anil K. Tripathi Nikhil Gupta Ajai Kumar Anil K. Singh Abbas A. Mahdi Rajendra Prasad Raj K. Singh 《Indian journal of clinical biochemistry : IJCB》2004,19(1):14-20
The circadian periodicity of plasma lipid peroxide levels and activities of superoxide dismutase (SOD), catalase (CAT) and
glutathione peroxidase (GPx) were studied in 50 clinically, bacteriologically and radiologically proven fresh cases of pulmonary
tuberculosis (age: 21–45 years) and 60 age-matched healthy volunteers with diurnal activity from 06∶00 to about 22∶00 and
nocturnal rest. A marked circadian variation in plasma lipid peroxide level was recorded in healthy subjects and pulmonary
tuberculosis patients with significant amplitude and acrophase around 16∶21 and 17∶12 respectively. The acrophase tended to
be delayed in tuberculosis patients. Furthermore, a statistically significant circadian rhythm was found in SOD, CAT and GPx
activities in normal volunteers and pulmonary tuberculopsis patients. SOD and CAT enzyme activity was noted to be maximum
at 06∶00 and minimum at 00∶00 in tuberculosis patients. The circadian acrophase for GPx activity was recorded at 16∶15 in
normals and around 22∶45 in patients. Moreover, the activity was found to be decreased at all sampling hours during 24-hours
sleep-awake period in patients in comparison to healthy counterparts. The MESOR and circadian amplitude also decreased markedly.
The decreased activity of measured antioxidant enzymes in pulmonary tuberculosis patients could probably be associated with
oxidative stress and/or decreased anti-oxidant defensive mechanism in such patients. 相似文献
173.
H. K. Bid Ajay Kumar R. D. Mittal 《Indian journal of clinical biochemistry : IJCB》2006,21(1):137-141
The Internet is a massive expanding body of information, which is likely to play a significant role for clinical Biochemists
and researchers in patient health care across the world. This expansion has been matched by an increase in the number of individuals
using the Internet. Since its inception in December 1969 the Internet has grown rapidly and is anticipated to expand 100%
in the coming next few years. This review illustrates to the Biochemists many uses of the Internet and hopefully provides
a useful resource for professional and personal use. To explain the origin, functions, use and impact of the Internet and
to provide a list of important website addresses related to Biochemistry. We undertook a detail scan of the Internet and identified
a large number of websites pertaining to Biochemistry. The sites were then thoroughly searched to evaluate their potential
usefulness to Biochemists, clinicians and researchers. This overview of the Internet and a compilation of important web-site
addresses are expected to stimulate and inculcate Biochemists in the use of the web in teaching, training and research. 相似文献
174.
Mukesh Nandave Ipseeta Mohanty T. C. Nag Shreesh Kumar Ojha Rajan Mittal Santosh Kumari Dharamvir Singh Arya 《Indian journal of clinical biochemistry : IJCB》2007,22(1):22-28
The present study evaluated the cardioprotective potential of vitamin-E by studying its effect on hemodynamic parameters,
lipid peroxidation, myocyte injury marker and ultrastructural changes in model of isoproterenol-induced myocardial necrosis
in rats. Wistar albino male rats (150–200 g) were randomly divided into saline, ISP control, and vit E groups. Vitamin E group
was administered vitamin E at a dose of 100mg/kg/day while saline and ISP control groups received saline orally for one month.
On 29th and 30th day, ISP (85 mg/kg, sc) was administered at an interval of 24 h to vit E and ISP control rats. On 31st day, rats of all groups were anesthetized and hemodynamic parameters were recorded. At the end of experimentation, animals
were sacrificed; hearts were excised and processed for biochemical and ultrastructural studies. ISP administration produced
marked cardiac necrosis as evidenced by significant decrease in my ocardial creatine kinase-MB as well as increase in malonaldialdehyde
levels. ISP-induced myocardial necrosis resulted in myocardial dysfunction as evidenced by significant depression in heart
rate and mean arterial pressure in the ISP control group as compared to saline control. Salient ultrastructural changes including
extensive loss of myofibrils, muscle necrosis, loss of mitochondria, and formation of several intracytoplasmic vacuoles and
lipid droplets further confirmed the ISP-induced myocardial damage. However, subsequent to ISP challenge, vit E treatment
significantly preserved the myocardium by restoring myocardial CK-MB activity, inhibiting the ISP-induced lipid peroxidation
and ultrastructural changes. Additionally, pre-and co-treatment of vit E prevented the deleterious ultrastructural changes
caused by ISP. These beneficial effects of chronic vit E treatment also translated into significant restoration of the altered
hemodynamic parameters. The present study clearly demonstrated the cardioprotective potential of vit E at dose of 100 mg/kg
in ISP-induced model of myocardial necrosis in rats. The significant restoration of altered hemodynamic parameters, myocardial
CK-MB activity, prevention of ISP-induced rise in lipid peroxidation and ultrastructural changes may confirm its cardioprotective
effect. 相似文献
175.
The white spot syndrome virus (WSSV) is one of the deadly pathogens of penaeid shrimps and other crustaceans. The WSSV virion
consists of an enveloped rod-shaped nucleocapsid enclosing a large circular double stranded DNA genome of 305 Kb with 181
open reading frames. The two major structural genes, VP19 and VP28 were amplified from the genomic DNA of Chinese isolate
of WSSV and cloned in pUCm-T vector and sub cloned in pET-30a (+) vector. The expressions of genes inE. coli (BL21) were confirmed by SDS-PAGE analysis. The clones were sequenced, submitted to the gene bank and the Xiang Shan strain
of WSSV were compared with the previous reported sequence of WSSV of various regions which revealed that VP19 and VP28 gene
sequences had certain differences from the sequences of similar genes of the isolate already reported. The recombinant proteins
expressed, purified and characterized. 相似文献
176.
Subir Kumar Das Hiran K. R. Sukhes Mukherjee D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):99-104
Damaging effects of reactive oxygen species on living systems are well documented. They include oxidative attack on vital
cell constituents. Chronic ethanol administration is able to induce an oxidative stress in the central nervous system. In
the present study, 16–18 week-old male albino rats of Wistar strain were exposed to different concentration of ethanol for
4 weeks. This exposure showed profound effect on body weight. Ascorbic acid level; and activities of alkaline phosphatase
and aspartate transaminase in the brain are dependent on the concentration of ethanol exposure. Chronic ethanol ingestion
elicits statistically significant increase in thiobarbituric acid reactive substances level and decrease in gluatathione level
in the brain. It reduces superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activities in a
dose dependent manner. However, histological examination could not reveal any pathophysiological changes. Therefore, we conclude
that biochemical alterations and oxidative stress related parameters respond early in alcoholism than the histopathological
changes in brain. 相似文献
177.
Herman Sunil D'Souza Geraldine Menezes T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2003,18(2):154-160
Heavy metals are important toxicants known to exert adverse effects in humans and animals, given sufficient exposure and accumulation
in the body. This has a great concern both at personal and public health risk. Heavy metals are also known to interact with
the essential trace minerals at the level of absorption and also during the metabolism. The adverse effects of the absorbed
and accumulated heavy metals include neurological, reproductive, renal and hematological systems. Children are more sensitive
than adults to the effects of lead. Efforts are made to understand the mechanism of the interactions of heavy metals with
essential trace minerals at the level of absorption. With available sensitive and specific methodologies like Anodic Stripping
Voltammetry for the evaluation of the levels of toxic heavy metals such as lead, cadmium, mercury etc., better understanding
of heavy metal absorption is made possible.
Due to the poor nutritional standards, risk of heavy metal exposure is still a major concern in developing countries. Studies
carried out by the author have provided evidence towards the understanding of the prevailing mechanisms of metal-metal interaction
at the intestinal level. During growth and development the demand for the essential minerals being at higher level, differentiation
of various essential metals and heavy metals pose an inherent problem due to certain common properties shared by them. With
this approach to the problem of heavy metal toxicity, it is preventable not only with environmental intervention but also
by the nutritional management. 相似文献
178.
Uday Kumar Anand Sharan Shaheena Kamal 《Indian journal of clinical biochemistry : IJCB》2003,18(2):6-7
Usually CPK, CK-MB and lactate dehydrogenase (LDH) enzymes are measured in blood during the period of myocardial infarction.
The changes in LDH assay indicates duration of the infarction.
The level of lactate dehydrogenase is 500 times greater in tissue than those found in serum. A small mass of damaged tissue
causes leakage of enzyme and increases its level in serum.
Any cause of tissue break down/hemolysis which is sufficiently severe can produce LDH pattern similar to that in myocardial
infarction.
We report this case of small bowel volvulus showing significant increase in LDH.
It may be due to tissue necrosis which increases the level of LDH in serum. 相似文献
179.
Lipid peroxidation by measurement of Thiobarbituric Acid Reactive Substances (TBARS) and antioxidant status by determining
the activities of the enzymes, Catalase (Cat), Glutathione Peroxidase (GPx) and Superoxide Dismutase (SOD) and the level of
Reduced Glutathione (GSH) in the erythrocytes of patients with type 2 Diabetes Mellitus were investigated. It was observed
that the level of TBARS in the erythrocytes was increased by 50% showing a significant generation of free radicals in the
erythrocytes of these patients. The activities of both Cat and SOD were enhanced while that of GPx was not altered. The level
of GSH was also not changed. 相似文献
180.
Minal Vaish Raj Kumar R. D. Mittal Balraj Mittal 《Indian journal of clinical biochemistry : IJCB》2004,19(2):156-162
Microsatellite instability (MSI) characterized by alterations at simple repetitive genomic sequences is a distinct mechanism in tumorogenesis. Central nervous system (CNS) tumors have been reported to exhibit MSI, indicator of defective mismatch repair system with controversies. The present study was undertaken to examine sixteen primary brain and two spinal tumors for MSI at six mono: BAT-26, BAT-40, BAX, TGFßRII, IGFIIR and hMSH3 and four dinucleotide loci: D2S123, D9S1851, D9S283 and D18S58. Polymerase chain reaction (PCR) was done to amplify tumour and blood DNA, analyzed on 8% denaturing Polyacrylamide gel followed by autoradiography. Out of 18 CNS tumors examined, 39% exhibited MSI at BAT-26, BAT-40, D9S1851, D9S283 and D18S58 in tumoral DNA. However, no alteration was observed at BAX, TGFßRII, IGFIIR, hMSH3 and D2S123 loci. Low incidence of MS1-high hypothesizes role of MSI in evolution of CNS tumors but not in cancer initiation or progression. 相似文献