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101.
102.
The present study was conducted to evaluate the ability of a high biomass producing, drought tolerant succulent plant Mauritius hemp (Furcraea gigantea Vent.) for its tolerance to different levels of Cr (0, 25, 50, 100 and 200 mg Cr kg soil?1) and its potential for phytoremediation purposes. Based on the data on inhibition of the growth of plants with Cr, tolerance index and grade of growth inhibition, it was observed that the plant could tolerate up to 50 mg Cr kg ?1 soil. Absorption of Cr from soil to plant and its translocation into plant tissues were discussed in terms of bio concentration factor (BCF), transfer factor (TF), and translocation efficiency (TE%). Cr was mainly accumulated in the roots and exclusion of Cr was found to be the principal physiological tolerance mechanism followed by a marked increase in proline, ascorbic acid, total free amino acids in the leaf tissue and malic acid in the rhizosphere samples to counter Cr stress. Based on the tissue concentration of Cr (< 300 μg g?1 in the leaves and TF<1), it was concluded that, Furcraea gigantea could not be considered a hyperaccumulator and therefore unsuitable for phytoextraction of Cr. Nevertheless, Furcraea gigantea could be a suitable candidate for phytostablization of Cr contaminated soils.  相似文献   
103.
The potential of an ornamental shrub Crown of thorns (Euphorbia milli) was evaluated for remediation of soil contaminated with Cr. The plant is one of the rare succulent ornamental shrubs with a slow to moderate growth rate and is capable of blooming almost year-round. The plant could tolerate well up to 75 mg of applied Cr and beyond that there was mortality of plants. Though the plant could not be classified as a hyperaccumulator, the plant was still very efficient in translocating Cr from roots to shoots as evident from the data on uptake and translocation efficiency values. The translocation efficiency of over 80% in our study demonstrates that a large proportion of Cr has been translocated to the harvestable biomass of the plant and therefore, this plant could be effectively recommended for the remediation of soils contaminated with low to medium level of contamination i.e., up to 50 mg/kg soil.  相似文献   
104.

Objective

In this prospective, longitudinal study of young children, we examined whether a history of preschool generalized anxiety, separation anxiety, and/or social phobia is associated with amygdala-prefrontal dysregulation at school-age. As an exploratory analysis, we investigated whether distinct anxiety disorders differ in the patterns of this amygdala-prefrontal dysregulation.

Methods

Participants were children taking part in a 5-year study of early childhood brain development and anxiety disorders. Preschool symptoms of generalized anxiety, separation anxiety, and social phobia were assessed with the Preschool Age Psychiatric Assessment (PAPA) in the first wave of the study when the children were between 2 and 5 years old. The PAPA was repeated at age 6. We conducted functional MRIs when the children were 5.5 to 9.5 year old to assess neural responses to viewing of angry and fearful faces.

Results

A history of preschool social phobia predicted less school-age functional connectivity between the amygdala and the ventral prefrontal cortices to angry faces. Preschool generalized anxiety predicted less functional connectivity between the amygdala and dorsal prefrontal cortices in response to fearful faces. Finally, a history of preschool separation anxiety predicted less school-age functional connectivity between the amygdala and the ventral prefrontal cortices to angry faces and greater school-age functional connectivity between the amygdala and dorsal prefrontal cortices to angry faces.

Conclusions

Our results suggest that there are enduring neurobiological effects associated with a history of preschool anxiety, which occur over-and-above the effect of subsequent emotional symptoms. Our results also provide preliminary evidence for the neurobiological differentiation of specific preschool anxiety disorders.  相似文献   
105.

Background

Despite being a recognized standard of tuberculosis (TB) care internationally, mandatory TB case notification brings forth challenges from the private sector. Only three TB cases were notified in 2013 by private practitioners compared to 2000 TB cases notified yearly from the public sector in Alappuzha district. The study objective was to explore the knowledge, opinion and barriers regarding TB Notification among private practitioners offering TB services in Alappuzha, Kerala state, India.

Methods & Findings

This was a mixed-methods study with quantitative (survey) and qualitative components conducted between December 2013 and July 2014. The survey, using a structured questionnaire, among 169 private practitioners revealed that 88% were aware of mandatory notification. All patient-related details requested in the notification form (except government-issued identification number) were perceived to be important and easy to provide by more than 80% of practitioners. While more than 95% felt that notification should be mandatory, punitive action in case of failure to notify was considered unnecessary by almost two third. General practitioners (98%) were more likely to be aware of notification than specialists (84 %). (P<0.01). Qualitative purposive personal interviews (n=34) were carried out among private practitioners and public health providers. On thematic framework analysis of the responses, barriers to TB notification were grouped into three themes: ‘private provider misconceptions about notification’, ‘patient confidentiality, and stigma and discrimination ’and ‘lack of cohesion and coordination between public and private sector’. Private practitioners did not consider it necessary to notify TB cases treated with daily regimen.

Conclusion

Communication strategies like training, timely dissemination of information of policy changes and one-to-one dialogue with private practitioners to dispel misconceptions may enhance TB notification. Trust building strategies like providing feedback about referred cases from private sector, health personnel visit or a liaison private doctor may ensure compliance to public health activities.  相似文献   
106.
Nucleotide binding and oligomerization domain (NOD)-like receptors (NLRs) are innate immune receptors that recognize bacterial cell wall components and initiate host immune response. Structure and function of NLRs have been well studied in human and mice, but little information exists on genetic composition and role of these receptors in innate immune system of water buffalo—a species known for its exceptional disease resistance. Here, a comparative study on the functional domains of NOD1 and NOD2 was performed across different species. The NOD mediated in-vitro cellular responses were studied in buffalo peripheral blood mononuclear cells, resident macrophages, mammary epithelial, and fibroblast cells. Buffalo NOD1 (buNOD1) and buNOD2 showed conserved domain architectures as found in other mammals. The domains of buNOD1 and buNOD2 showed analogy in secondary and tertiary conformations. Constitutive expressions of NODs were ubiquitous in different tissues. Following treatment with NOD agonists, peripheral lymphocytes showed an IFN-γ response along-with production of pro-inflammatory cytokines. Alveolar macrophages and mammary epithelial cells showed NOD mediated in-vitro immune response through NF-κB dependent pathway. Fibroblasts showed pro-inflammatory cytokine response following agonist treatment. Our study demonstrates that both immune and non-immune cells could generate NOD-mediated responses to pathogens though the type and magnitude of response depend on the cell types. The structural basis of ligand recognition by buffalo NODs and knowledge of immune response by different cell types could be useful for development of non-infective innate immune modulators and next generation anti-inflammatory compounds.  相似文献   
107.

Aims

Patients with sickle cell disease have significant morbidity and mortality. Pulmonary hypertension is suggested to be an important contributor but its nature and severity in these patients and how best to non-invasively assess it are controversial. We hypothesised that a high-output state rather than primary pulmonary vascular pathology may be the major abnormality in sickle cell disease. This study aimed to evaluate the characteristics and severity of pulmonary hypertension in patients with sickle cell disease using detailed echocardiography.

Methods and Results

We undertook a prospective study in 122 consecutive stable outpatients with sickle cell disease and 30 age, gender and ethnicity-matched healthy controls. Echocardiographic evaluation included 3D ventricular volumes, sphericity, tissue Doppler, and non-invasive estimation of pulmonary vascular resistance. 36% of patients had a tricuspid regurgitant velocity ≥2.5 m.s-1 but only 2% had elevated pulmonary vascular resistance and the prevalence of right ventricular dysfunction was very low. Patients with raised tricuspid regurgitant velocity had significantly elevated biventricular volumes and globular left ventricular remodelling, related primarily to anaemia. In a subgroup of patients who underwent cardiac catheterization, invasive pulmonary haemodynamics confirmed the echocardiographic findings.

Conclusions

Elevated cardiac output and left ventricular volume overload secondary to chronic anaemia may be the dominant factor responsible for abnormal cardiopulmonary haemodynamics in patients with sickle cell disease. 3D echocardiography with non-invasive estimation of pulmonary vascular resistance represents a valuable approach for initial evaluation of cardiopulmonary haemodynamics in sickle cell disease.  相似文献   
108.
Insulin-stimulated translocation of glucose transporter 4 (GLUT4) to cell membrane leading to glucose uptake is the rate-limiting step in diabetes. It is also a defined target of antidiabetic drug research. Existing GLUT4 translocation assays are based on time-consuming immunoassays and are hampered by assay variability and low sensitivity. We describe a real-time, visual, cell-based qualitative GLUT4 translocation assay using CHO-HIRc-myc-GLUT4eGFP cells that stably express myc- and eGFP-tagged GLUT4 in addition to human insulin receptor (HIRc). GLUT4 translocation is visualized by live cell imaging based on GFP fluorescence by employing a cooled charge-coupled device camera attached to a fluorescent microscope. This video imaging method and further quantitative analysis of GLUT4 on the cell membrane provide rapid and foolproof visual evidence that this method is suitable for screening GLUT4 translocation modulators.  相似文献   
109.
Various efforts made to stop the deadly epidemic of HIV since its discovery in 1983 remain unsuccessful and this virus still continues to claim the lives of millions of individuals every year. The viral effect in the cell is complicated and the overall disease outcome is the result of interaction between a few viral proteins and complex host immune response. Because it has been reported that XPG (Xeroderma pigementesum group G) gene does play a role in reducing UV induced apoptosis and participate in Nucleotide Excision Repair (NER) process of DNA damage, it was hypothesized that polymorphism in this gene may have a role in HIV 1 disease progression to AIDS. The aim of the present study, therefore, was to find out the association between XPG gene polymorphism and its effect on the rate of HIV 1 disease progression to AIDS. 300 HIV seropositive cases and an equal number of age and sex matched controls were recruited for the study from north Indian population. The PCR-RFLP method was utilized to genotype 600 study subject for the XPG Asp 1104 His gene polymorphism. There was significant difference in the frequency of the His/His variant genotype (OR 1.95, 95% CI = 1.93–3.63, P = 0.04) between cases and controls indicating a probable role of this gene in host viral interactions.  相似文献   
110.
Integral membrane proteins constitute a major constituent of lipid bilayer both in prokaryotes and eukaryotes. The statistical analysis was carried out to determine the bias in amino acid distribution between prokaryotic and eukaryotic integral membrane proteins (pIntMPs and eIntMPs). Our results indicate that both pIntMPs and eIntMPs demonstrate the striking similarity in amino acid distribution in their transmembrane and extramembranous region. pIntMPs have relatively greater functional importance for Gly and Asn in comparison to eIntMPs.  相似文献   
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