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排序方式: 共有1479条查询结果,搜索用时 15 毫秒
931.
Methadone is a potent analgesic and sedative. It is widely used in the treatment of heroin addiction and is often encountered in forensic specimens. In electron impact (EI) gas chromatography/mass spectrometry (GC/MS) mode, methadone produces predominantly a m/z 72 ion, which is not sufficiently characteristic for identification. Determination of the molecular ion, which can be achieved using chemical ionization (CI) provides diagnostic information and better identification of the drug. This paper describes the development of a positive ion CI GC/MS procedure, using a liquid reagent gas and ion trap instrumentation, for the determination of methadone and its metabolites in urine. CI generally produces a single molecular ion spectrum, but optimization of the reagent gas parameters increases the fragmentation of the molecule, allowing determination of ion ratios if required. The procedure is sensitive, diagnostic and is currently in routine use in our laboratory. 相似文献
932.
Political Behavior - For years, Republicans in Congress promised to “repeal and replace” the Affordable Care Act. The results of the 2016 elections put them in position to take action... 相似文献
933.
Melissa A. Pasquale‐Styles M.D. Christian M. Crowder Ph.D. Jeannette Fridie M.A. Sarah S. Milla M.D. 《Journal of forensic sciences》2014,59(6):1668-1671
Bilateral symmetric bone nodules were observed in the anterolateral first ribs of an infant with shaking injuries at autopsy. The location prompted diagnostic considerations of healing fractures versus anomalous articulations with pseudarthroses. The forensic pathologist worked with forensic anthropologists and pediatric radiologists to evaluate autopsy findings and compare premortem and postmortem X‐rays. Gross examination of the bones by the pathologist and anthropologists confirmed bilateral, callus‐like bone nodules in first‐rib locations associated with pseudarthroses. Histologic examination of one of the bones further showed features most consistent with pseudarthrosis, not a healing fracture. Radiologists then compared multiple premortem and postmortem radiographs that showed no remodeling of the bone over a 2‐week interval between the time of injury and death, which would be unexpected for a healing fracture in an infant. This multidisciplinary approach resulted in the appropriate diagnosis of pseudarthroses due to anomalous articulations, an uncommon finding in forensic pathology. 相似文献
934.
With the growing importance of public engagement in science policy making and declining levels of public trust in food production, the European Food Safety Authority (EFSA) has attempted to embed “good governance” approaches to strengthen scientific independence and open up risk decision making, which include the use of public consultations. However, “opening up” of risk assessment policies reveals some tensions; namely, balancing the goals of scientific excellence and transparency, protecting science from interests, addressing value judgments, and limited opportunities to debate ethical and social issues. EFSA's development of risk assessment policy for genetically modified animals is used as a case study to analyze these tensions. This analysis suggests that in order to fulfill good governance commitments and maintain trust in risk governance, closer cooperation between EFSA and the European Commission is required to provide “space” for debating the broader risk management issues. This publically accessible space may be needed alongside rather than instead of EFSA's consultation. 相似文献
935.
936.
Sarah Kerrigan Ph.D. Ashley Mott M.S. Breanna Jatzlau M.S. Francisco Ortiz M.S. Laura Perrella M.S. Sarah Martin M.S. Kelsie Bryand M.S. 《Journal of forensic sciences》2014,59(1):175-183
Designer psychostimulants are known by recreational drug users to produce a complex array of adrenergic and hallucinogenic effects. Many of these drugs are not targeted during routine toxicology testing and as a consequence, they are rarely reported. The purpose of this study was to develop a procedure for the detection of 15 psychostimulants in urine using liquid chromatography–tandem mass spectrometry (LC‐MS/MS), specifically 2,5‐dimethoxy‐4‐bromophenethylamine (2C‐B), 2,5‐dimethoxy‐4‐chlorophenethylamine (2C‐C), 2,5‐dimethoxy‐4‐methylphenethylamine (2C‐D), 2,5‐dimethoxy‐4‐ethylphenethylamine (2C‐E), 2,5‐dimethoxyphenethylamine (2C‐H), 2,5‐dimethoxy‐4‐iodophenethylamine (2C‐I), 2,5‐dimethoxy‐4‐ethylthiophenethylamine (2C‐T‐2), 2,5‐dimethoxy‐4‐isopropylthiophenethylamine (2C‐T‐4), 2,5‐dimethoxy‐4‐propylthiophenethylamine (2C‐T‐7), 2,5‐dimethoxy‐4‐bromoamphetamine (DOB), 2,5‐dimethoxy‐4‐chloroamphetamine (DOC), 2,5‐dimethoxy‐4‐ethylamphetamine (DOET), 2,5‐dimethoxy‐4‐iodoamphetamine (DOI), 2,5‐dimethoxy‐4‐methylamphetamine (DOM), and 4‐methylthioamphetamine (4‐MTA). Analytical recoveries using solid‐phase extraction were 64–92% and the limit of detection was 0.5 ng/mL for all drugs except 2C‐B (1 ng/mL). The assay was evaluated in terms of analytical recovery, precision, accuracy, linearity, matrix effect, and interferences. The technique allows for the simultaneous detection of 15 psychostimulants at sub‐ng/mL concentrations. 相似文献
937.
938.
939.
G E Moore 《Journal - Forensic Science Society》1970,10(3):179-180
940.
Assessing self-harm through brief multiple choice items is simple and less invasive than more detailed methods of assessment.
However, there is currently little validation for brief methods of self-harm assessment. This study evaluates the extent to
which adolescents’ perceptions of self-harm agree with definitions in the literature, and what level of question detail produces
optimal concordance rates. Two hundred and thirty-three (69% female) first year university students aged 17–21 completed a
self-harm coding task; we created three levels of question detail and randomly allocated participants to three study groups:
brief, low detail, and high detail. The present findings suggest that that adolescents’ perceptions of self-harm are generally concordant with a consensus definition
of self-harm. Low level of detail in the question produced greatest accuracy in responses; adolescents who demonstrated adequate
task understanding were able to correctly identify 94% of examples of self-harm behaviour and 86% of examples of behaviour
that were not self-harm. We identified lower concordance rates for eating disordered behaviour and recreational petrol sniffing.
This indicates that adolescents perceive these behaviours to be self-harm, in contrast to the reference definition we utilised.
Overall, this study provides support for using a brief assessment of self-harm where minimal detail regarding self-harm behaviour
is required. 相似文献