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71.
Depression in older people slightly differs from younger subjects adults. Generally, typical depressive symptoms are overlooked by other symptoms. The most frequent ones are excessive preoccupation with health and complaints about physical symptoms. Anxiety is a common accompaniment of depression in later life. Poor subjective memory or dementia-like and psychotic symptoms are also common in depression in the elderly. The exogenous depression, the most common forms of depression in elderly people, has a little response to antidepressants. The endogenous depression is associated with high risk of suicide. Depression in older people often coexists with physical disorders. The most frequently encountered is Parkinson's disease. Depression could also be one of the side effect of the use of drugs for physical illnesses. The Tricyclic antidepressants (TCAs) are generally too toxic for elderly people and should not be considered as drugs of first choice. Currently, the drugs of choice are the serotonin-selective reuptake inhibitors (SSRIs). They have an antidepressant effect similar to that of (TCAs), but they are less toxic. The antidepressant treatment in the elderly is usually initiated at a low starting dose, ideally no more than half the usually recommended for the adults. For psychotic depression a combination of an antidepressant used in conjunction with antipsychotic drug is more effective than an antidepressant administered alone. The treatment should be continued for six months at least in order to reduce the risk of relapse. Moreover, long-term treatment is recommended because of the high risk of recurrence.  相似文献   
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This review describes recent research in the development of tank systems based on complex metal hydrides for thermolysis and hydrolysis. Commercial applications using complex metal hydrides are limited, especially for thermolysis-based systems where so far only demonstration projects have been performed. Hydrolysis-based systems find their way in space, naval, military and defense applications due to their compatibility with proton exchange membrane (PEM) fuel cells. Tank design, modeling, and development for thermolysis and hydrolysis systems as well as commercial applications of hydrolysis systems are described in more detail in this review. For thermolysis, mostly sodium aluminum hydride containing tanks were developed, and only a few examples with nitrides, ammonia borane and alane. For hydrolysis, sodium borohydride was the preferred material whereas ammonia borane found less popularity. Recycling of the sodium borohydride spent fuel remains an important part for their commercial viability.  相似文献   
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Summary: The effect of vanadate on urinary excretion of acid and electrolyte in dogs with hydrochloric acid (HCI)-induced acute metabolic acidosis was studied. Vanadate caused no changes in systemic and renal haemodynamics, blood parameters and net acid excretion (NAE) in the control group. In the acute metabolic acidosis group, metabolic acidosis per se also had no effect on haemodymic parameters. Fractional excretion of bicarbonate was decreased, while NAE was markedly increased. Following vanadate treatment, acute acid-loaded animals showed an increase in mean arterial pressure (MAP), but a decreased glomerular filtration rate and effective renal plasma flow. These animals had reduced NAE compared to that seen with HCI alone. Thus, vanadate impaired the renal adaptive responses to acute metabolic acidosis. the decreased NAE induced by vanadate might be caused by its known inhibitory effect on hydrogen-potassium-adenosine triphosphatase (H-K-ATPase) and sodium-potassium-adenosine triphosphatase (Na-K-ATPase), and by renal vasoconstriction.  相似文献   
75.
Kalach 360 SL (KL) is a commercial herbicide which contains 360?g/l of glyphosate used in both agricultural and urban areas throughout the world including Tunisia. We aimed to evaluate the effects of KL on rats’ renal system. Female Wistar rats were divided into three groups: group 1 (n?=?6) received a standard diet and served as control, groups 2 and 3 (n?=?12 each) received 0.07?ml (D1: 126?mg/kg), and 0.175?ml (D2: 315?mg/kg) of KL, respectively, for 60 d. The chronic exposure to KL induced a significant increase in plasma creatinine, urea, and uric acid levels. Creatinine clearance decreased in KL-treated groups, compared with controls. Several urine parameters, such as urine-specific gravity and urine osmolality, significantly decreased, while dieresis and urinary Na/K?+?ratio increased in KL-treated groups. These findings suggested a distal tubular damage caused by tubular necrosis. Moreover, the chronic exposure to KL induced an increase in lipid peroxidation (LPO) and a decrease in antioxidant status, enzymatic activities (superoxide dismutase and catalase) and non-enzymatic levels (vitamin C), which led to an oxidative stress. Histopathological studies showed a peritubular inflammatory reaction, nephrose, fragmented glomeruli, necrotic epithelial cells, and tubular dilatation. These results could have significant health implications for animal and human populations. Further data are necessary to investigate the potential consequences of chronic dose exposure during life.  相似文献   
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Journal of NeuroVirology - Neurological cytomegalovirus (CMV) infections especially extensive longitudinal myelitis are extremely rare in immunocompetent adults. However, we hereby report a case of...  相似文献   
79.

Introduction

Several studies have shown a strong correlation between the serum vitamin D level and asthma severity and deficits in lung function.

Objective

Study the relationship between vitamin D and the severity of asthma by targeting five SNPs of vitamin D metabolism gene pathway in a Tunisian adult asthmatics population.

Methods

Our case–control study includes 154 adult asthmatic patients and 154 healthy Tunisian subjects. We genotyped many variants in three human genes encoding key components of the vitamin D metabolism, CYP2R1, CYP27B1, GC. The GC gene rs4588 and rs7041 polymorphisms were analysed using the PCR-RFLP method, while rs10741657 and rs12794714 for CYP2R1 gene and rs10877012 of CYP27B1 gene were investigated using TaqMan PCR genotyping techniques.

Results

We found that the presence of at least one copy of the rs12794714 A, allele was associated with lower risk of developing asthma (OR 0.61). Further, the rs12794714 is a protector factor against asthma severity (OR 0.5). However, the presence of rs10877012 TG genotype is a risk factor related to asthma severity (OR 1.89). When we classified the population according to sex, our results showed that rs10877012 TT genotype was a risk factor for women subjects (OR 6.7). Moreover, the expression of TT genotype was associated with a higher risk of asthma in non-smoker patients (OR 7.13). We found a significant lower VD serum levels in asthmatics than controls but no impact of the polymorphisms on VD levels.

Conclusions

We found that rs12794714 and rs10877012 SNPs were associated with asthma risk.
  相似文献   
80.
Context: Nitraria retusa (Forssk.) Asch. (Nitrariaceae) is a medicinal plant which produces edible fruits whose antioxidant activity has been demonstrated.

Objective: The current study elucidates the potential protective effect of N. retusa fruit aqueous extract against nephrotoxicity induced by penconazole, a triazole fungicide, in the kidney of adult rats.

Materials and methods: Adult Wistar rats were exposed either to penconazole (67?mg/kg body weight), or to N. retusa extract (300?mg/kg body weight) or to their combination. Penconazole was administered by intra-peritoneal injection every 2 days from day 7 until day 15, the sacrifice day, while N. retusa extract was administered daily by gavage during 15 days. Oxidative stress parameters, kidney biomarkers and histopathological examination were determined.

Results: Nitraria retusa extract administration to penconazole treated rats decreased kidney levels of malondialdehyde (?10%), hydrogen peroxide (?12%), protein carbonyls (PCOs, ?11%) and advanced oxidation protein products (AOPP, ?16%); antioxidant enzyme activities: catalase (?13%), superoxide dismutase (?8%) and glutathione peroxidase (GPx, ?14%), and the levels of non-enzymatic antioxidants: non-protein thiols (?9%), glutathione (?7%) and metallothionein (?12%). Furthermore, this plant extract prevented kidney biomarker changes by reducing plasma levels of creatinine, urea, uric acid and LDH and increasing those of ALP and GGT. Histopathological alterations induced by penconazole (glomeruli fragmentation, Bowman’s space enlargement, tubular epithelial cells necrosis and infiltration of inflammatory leucocytes) were attenuated following N. retusa administration.

Discussion and conclusion: Our results indicated that N. retusa fruit extract had protective effects against penconazole-induced kidney injury, which could be attributed to its phenolic compounds.  相似文献   
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