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1.
Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials. 相似文献
2.
John A. Tomenson Graham A. Matthews 《International archives of occupational and environmental health》2009,82(8):935-949
Purpose The present investigation looks in detail at the causes and types of health incidents reported by 6,300 mainly smallholder
agrochemical users in 24 countries during 2005 and 2006.
Methods The investigation is based on a questionnaire survey of knowledge, attitude and practice that concentrated on the sequence
of events from purchasing the pesticide to disposal. Information was also collected about health problems experienced while
using agrochemicals. The survey targeted mainly smallholder knapsack spray operators who were expected to be at a highest
risk of exposure.
Results In the 12 months prior to interview, 1.2% of users reported an agrochemical-related incident that required hospital treatment,
5.8% reported an incident requiring at least trained medical treatment but not hospitalisation and 19.8% reported only a minor
sign or symptom. Users who had experienced an incident involving agricultural equipment were 3.38 (95% CI 2.29–4.99) times
more likely to experience an agrochemical-related health incident, but confident users who felt that their use of personal
protective equipment while spraying was best practice were 0.60 (95% CI 0.44–0.84) times less likely to experience such an
incident. Over 80% of product-related incidents were caused by insecticides and the incidence rate per spraying time for incidents
linked to insecticides was significantly higher than that for fungicides or herbicides. Headache/dizziness and nausea/vomiting,
often smell related, were the most common symptoms reported by users who listed agrochemical products that had caused them
health problems (52 and 38% of product mentions, respectively).
Conclusions In most countries, the incidence of serious health effects was low; however, there was a high incidence of minor signs and
symptoms in a few countries, especially in Africa. A disproportionate number of incidents occurred during insecticide use
relative to the time that they were sprayed. Failure to exercise caution as indicated by whether users had incidents involving
agricultural equipment or livestock, and lack of confidence in their practices were the most important predictors of agrochemical-related
incidents. 相似文献
3.
4.
Maximum Residue Limits (MRLs) are standards that represent the maximum residue concentration expected to be found if a pesticide is applied according to good agricultural practice (GAP). MRLs are established only where the residues in food resulting from particular use patterns of the pesticide pass the public health risk assessment. Foodstuffs are monitored for MRL compliance and MRL exceedance can have economic and trade consequences. There is a trade-off when deciding on values for MRLs. The aim is to establish MRLs at levels that are high enough to prevent chance exceedance but not so high that misuse will not be detected. Small data sets typically available for estimating MRLs present problems for establishing consistent values. A review of MRL estimation methods is presented together with an assessment of the various methods. 相似文献
5.
Summary This article reports TLC data (corrected Rf values; R
f
c
values) of 170 commonly used pesticides which are regularly encountered in toxicological analysis. Silica gel was used as the stationary phase and three binary systems were chosen as solvents. 相似文献
6.
7.
Gomes J Lloyd OL Revitt DM 《International archives of occupational and environmental health》1999,72(1):40-45
Farm workers in developing countries tend not to use protective measures while handling pesticides. This study investigates
the use of personal protection equipment and the practice of safety and hygiene procedures in the handling of pesticides in
agriculture. Methods: Through a multi-stage sampling technique, one-fifth of the farms in a region were selected and all the farm workers at these
farms were included in the study. A comparison population matching in age, socio-economic status and stay in the region was
selected. A specifically designed questionnaire was used to collect information on the use of protective measures and the
practice of safety and hygiene during work and on the disposal of empty pesticide containers. Blood pressure and erythrocyte
acetylcholinesterase (AChE) activity were measured in the exposed and the unexposed populations. Results: Protective equipment was worn by a minority of farm workers – gloves, by 35%; work coveralls, by 36%; a scarf to cover the
nose and mouth, by 39%; and shoes at work, by 79%. With regard to personal hygiene measures, 83% of the workers changed clothes
after work and the same proportion took a shower after work; 63% and 46% drank and ate while at work respectively; and 11%
used articles of domestic use in the preparation of pesticides on the farm. Most of the farm workers (96%) were asked to prepare
pesticides for spraying by the foreman and 61% were asked to spray the pesticides on the crops. AChE activity was highly significantly
depleted in the exposed population as compared with the unexposed population. Conclusions: AChE depletion was found to be negatively associated with the use of gloves, of work coveralls, and of a scarf to cover the
nose and mouth and with the implementation of safety and hygiene procedures on the farm. AChE depletion was positively associated
with the frequency of pesticide spraying.
Received: 30 January 1998 / Accepted: 19 August 1998 相似文献
8.
H. -L. Brassow K. Baumann G. Lehnert 《International archives of occupational and environmental health》1981,48(1):81-87
Summary Sixty male workers in a lindane (y-hexachlorocyclohexane)-producing factory were examined with regard to health in comparison with an external control group of 20 clerks.Case history, physical examination, neurologic status, and ECG revealed no significant differences between groups. However, the following significant differences in clinical-chemical blood tests were ascertained: higher polymorphonuclear leukocyte count, lower lymphocyte count, higher reticulocyte count, lower prothrombin (Quick's) test, and lower blood concentrations of creatinine and uric acid. No significant differences were observed in total red and white blood cell as well as platelet counts, hemoglobin content, the other counts of differential blood picture, -GT, GOT, GPT, LDH, cholinesterase, triglycerides, cholesterol, and urea.In spite of a pronounced exposure to the -, -, and -isomers of hexachlorocyclohexane, no signs of severe impairment of health were observed; only small deviations in some laboratory tests were found having no pathologic significance. However, biological monitoring and health supervision of HCH-exposed workers should be carried out. 相似文献
9.
S. Tomczak Priv.Doz.Dr. K. Baumann G. Lehnert 《International archives of occupational and environmental health》1981,48(3):283-287
Summary In a lindane (-hexachlorocyclohexane)-producing factory 54 male workers (mean age 40 years, mean duration of exposure 8 years) were studied with regard to their blood levels of testosterone, LH, and FSH. Twenty clerks of nearly the same age were examined for control purposes in the same way. Serum-LH concentrations of the exposed workers were significantly higher than in controls. Geometric mean values were 8.8 mIU/ml and 5.7 mIU/ml respectively. On the other hand, FSH levels were insignificantly higher. Concerning testosterone concentrations in serum, these were found to be slightly lower in the group of workers than in control persons but this difference could not be proved to be statistically significant.These results indicate certain perturbations in sex hormone regulation probably as a consequence of HCH-exposure. To judge the pathological significance of these alterations further investigation will be necessary. 相似文献
10.
The challenges faced on pesticide extraction from biological samples are finding a method that allows a multi-residue extraction, pre-concentration, clean-up, and isolation of analytes in just one step. In this sense, the hollow fiber – liquid phase microextraction method (HF- LPME) in the "solvent bar" mode was used to optimize and validate a method for pesticide multi-residue analysis in blood plasma at trace levels, through gas chromatography coupled with a flame ionization detector (GC-FID). Hollow fiber solvent bar microextraction HF-SBME was carried out with octanol immobilized into the pores of hydrophobic polypropylene fiber and disposed within a matrix of blood plasma, spiked with a mixture of pesticides (monocrotophos, lindane, aldrin, methyl parathion, endosulfan, dieldrin, DDD, DDT, and endrin). The optimization parameters evaluated were: extraction temperature and time, stirring speed, and salt concentration. A principal component analysis was performed to visualize the analytes' behaviour based on their explained variance, and then, a Box-Behnken analysis was generated to identify the optimum parameters. According to the PCA, all pesticides showed similar responses to the extraction method and the response of dieldrin exhibit the lowest variance. Moreover, the stationary points selected from the Box-Behnken analysis were 25.5 °C for the extraction temperature, 870 rpm for stirring speed, 16 min for extraction time, and 8.3 % w/v of salt concentration. Moreover, the validation results proved that HF-SBME is an alternative technique for pesticide multi-residue extraction in blood plasma. The analytes were able to concentrate, reaching 46 fold enrichment. The solvent type, sample and solvent volume were narrowed down without changing the method's precision or accuracy. The relative standard deviation was under 10 %, and the recovery was between 55 % and 105 % for the different analytes excepting lindane, which had lower recovery (27 %). The detection limits were 0.02 until 0.13 μg mL−1 for most of the pesticides used. Finally, HF-SBME is a good alternative for pesticide multi-residue extraction in complex matrices like plasma. 相似文献