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431.
A solid-phase enzyme immunoassay involving microtiter plates was recently proposed by International Diagnostic Systems corporation (IDS) to screen for buprenorphine in human serum. The performance of the kit led us to investigate its applicability in other biological matrices such as urine or blood, and also hair specimens. Low concentrations of buprenorphine were detected with the ELISA test and confirmed by HPLC/MS (buprenorphine concentrations measured by HPLC/MS: 0.3 ng/mL in urine, 0.2 ng/mL in blood, and 40 pg/mg in hair). The intra-assay precision values were 8.7% at 1 ng/mL of urine (n = 8), 11.5% at 2 ng/mL in serum (n = 8), and 11.5% at 250 pg/mg of hair (n = 8), respectively. The immunoassay had no cross-reactivity with dihydrocodeine, ethylmorphine, 6-monoacetylmorphine, pholcodine, propoxyphene, dextromoramide, dextrometorphan at 1 and 10 mg/L, or codeine, morphine, methadone, and its metabolite EDDP. A 1% cross-reactivity was measured for a norbuprenorphine concentration of 50 ng/mL. Finally, the immunoassay was validated by comparing authentic specimens results with those of a validated HPLC/MS method. From the 136 urine samples tested, 93 were positive (68.4%) after the ELISA screening test (cutoff: 0.5 ng/mL) and confirmed by HPLC/MS (buprenorphine concentrations: 0.3-2036 ng/mL). From the 108 blood or serum samples screened, 27 were positive (25%) after the ELISA test with a cutoff value of 0.5 ng/mL (buprenorphine concentrations: 0.2-13.3 ng/mL). Eighteen hair specimens were positive (72%) after the screening (cutoff: 10 pg/mg) and confirmed by LC/MS (buprenorphine concentrations: 40-360 pg/mg). The ELISA method produced false positive results in less than 21% of the cases, but no false negative results were observed with the immunological test. Four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that were added to 10 positive urine specimens (buprenorphine concentrations in the range 5.3-15.6 ng/mL), did not cause a false negative response by the immunoassay.  相似文献   
432.
Evaluation of nicotine and cotinine in human hair.   总被引:4,自引:0,他引:4  
To validate data on tobacco use, the authors investigated the use of hair samples for quantifying nicotine and cotinine by gas chromatography/mass spectrometry. Hair was taken from 22 nonsmokers and 42 smokers, cut close to the scalp at the back of the head. The hair (about 100 mg from each subject) was incubated in 3 mL of 1N NaOH at 100 degrees C for 1 h. After this, the samples were extracted by diethyl ether. The drugs were separated on a 12-m BP-5 capillary column and detected using selected ion monitoring (nicotine, m/z 84; cotinine, m/z 98). Hair from nonsmokers and smokers contains nicotine and cotinine. Although it is difficult to determine an absolute cutoff level, an amount greater than 2 ng of nicotine per milligram of hair can be used to differentiate smokers from nonsmokers. In the population of nonsmokers, the influence of environmental smoke exposure was noted.  相似文献   
433.
Fatal meprobamate self-poisoning   总被引:1,自引:0,他引:1  
A case involving a suicidal overdose resulting from the ingestion of 90 tablets (400 mg) of meprobamate is presented. The drug was quantified using a gas chromatograph equipped with a flame ionization detector (FID). While the blood level was 204.6 micrograms/ml, the maximum concentration was found in the heart (708 micrograms/g), confirming the cardiac toxicity of meprobamate. Other drugs were not detected.  相似文献   
434.
A collaborative case-control study was conducted in France in order to determine the prevalence of alcohol, cannabinoids, opiates, cocaine metabolites, amphetamines and therapeutic psychoactive drugs in blood samples from drivers injured in road accidents and to compare these values with those of a control population. Recruitment was performed in emergency departments of six university or general hospitals and comprised 900 drivers involved in a non-fatal accident and 900 patients (controls) who attended the same emergency units for a non-traumatic reason. Drivers and controls were matched by sex and age. Alcohol was determined by flame ionization-gas chromatography, drugs of abuse (DOA) by gas chromatography-mass spectrometry with the same analytical procedures in the six laboratories, and medicines by high performance liquid chromatography with diode array detection. Blood alcohol concentration exceeding 0.5 g/l (i.e. the legal French threshold) was found in 26% of drivers and 9% of controls. In the 18-27 years age range, alcohol was the only toxic found in blood samples of 17% drivers and 5% controls, leading to an odds-ratio (OR) of 3.8. A significant relationship was found between alcohol blood concentrations and OR values. All age groups confounded, the main active substance of cannabis, Delta(9) tetrahydrocannabinol (THC), was found in 10% of drivers and 5% of controls. In the less than 27 years old, THC (>1 ng/ml) was detected alone in the blood of 15.3% drivers and of 6.7% controls, giving OR=2.5, whereas there was no link between THC blood concentrations and OR value. THC was found alone in 60% of cases and associated with alcohol in 32%, with OR=4.6 between drivers and controls for this association. The difference in morphine prevalence between drivers (2.7%) and controls (0.03%) was highly significant (P<0.001), with OR=8.2. The number of positive cases for amphetamines and cocaine metabolites was too low for reaching any interpretation. The most frequently observed psychoactive therapeutic drugs were by far benzodiazepines, that were found alone in 9.4% of drivers and 5.8% of controls, which led to OR=1.7 (P<0.01).This study demonstrates a higher prevalence of opiates, alcohol, cannabinoids and the combination of these last two compounds in blood samples from drivers involved in road accidents than in those from controls, which suggests a causal role for these compounds in road crashes.  相似文献   
435.
A method is presented for the simultaneous identification and quantification of several CNS stimulants, including amphetamine in plasma and urine by GC/FID using mephentermine as an internal standard. No derivation is necessary and after a single alkaline extraction, GC analysis for the 11 compounds tested is achieved in 23 min. The lower limit of detectability was found to be 4 ng/ml for amphetamine in plasma. This method is sensitive, reproducible, selective and applicable in forensic and clinical toxicological analyses. Toxicological findings, after a fatality involving phendimetrazine are presented as an application of the procedure.  相似文献   
436.
Toxicological analyses on a putrefied cadaver are sometimes difficult to achieve because of the absence of blood and urine. In this study, maggots, living material, are proposed as a new medium of investigation in forensic medicine. Five drugs (triazolam, oxazepam, phenobarbital, alimemazine, and clomipramine) were identified and assayed in some tissues of a putrefied cadaver and in the maggots found on and in the body.  相似文献   
437.
Thus history suggests that dictators come in two types: one whose personal objectives often conflict with [economic] growth promotion and another whose interests dictate a preoccupation with economic development. The theory that determines which kind of dictatorship will prevail is missing. Absent this theory, the choice of a dictatorship can be viewed as a risky investment; economic outcomes may be very good or very bad but are surely uncertain  相似文献   
438.
439.
Several bodybuilders, all winners of international competitions, were arrested for trafficking of a number of doping agents including anabolic steroids, ephedrine, beta-adrenergics, human chorionic gonadotropin, antidepressants, and diuretics. In accordance with the recent French law against doping, the judge asked to test seven bodybuilders to identify doping practices. Hair and urine specimens were collected for analysis. After decontamination, a 100 mg hair strand was pulverized in a ball mill, hydrolyzed, extracted, and derivatized to be tested by GC/MS for anabolic steroids, beta-adrenergic compounds, ephedrine, and other doping agents. Urine was analyzed for anabolic steroids and metabolites, beta-adrenergic compounds, ephedrine, and human chorionic gonadotropin, in addition to a broad spectrum screening with GC/MS. The following compounds were detected in urine: ephedrine (29 and 36 ng/mL, n = 2), clenbuterol (0.2 to 0.3 ng/mL, n = 3), norandrosterone (4.7 to 100.7 ng/mL, n = 7), norethiocholanolone (0.9 to 161.8 ng/mL, n = 6), stanozolol (1 to 25.8 ng/mL, n = 4), methenolone (2.5 to 29.7 ng/mL, n = 4), testosterone (3 to 59.6 ng/mL, n = 7), epitestosterone (1 to 20.4 ng/mL, n = 7) and ratio testosterone/epitestosterone >6 for four subjects (18.5 to 59.6). The following drugs were detected in hair: ephedrine (0.67 and 10.70 ng/mg, n = 2), salbutamol (15 to 31 pg/mg, n = 3), clenbuterol (15 to 122 pg/mg, n = 6), nandrolone (1 to 7.5 pg/mg, n = 3), stanozolol (2 to 84 pg/mg, n = 4), methenolone (17 and 34 ng/ml, n = 2), testosterone enanthate (0.6 to 18.8 ng/mg, n = 5), and testosterone cypionate (3.3 to 4.8 ng/mg, n = 2). These results document the doping practice and demonstrate repetitive exposure to anabolic compounds and confirm the value of hair analysis as a complement to urinalysis in the control of doping practice.  相似文献   
440.
Frontal sinuses (FSs) have been studied in radiology, anthropology, and forensic anthropology. This study aimed to determine whether it was possible to predict the age and sex of an individual using FS volume. Sixty‐nine anonymized CT scans were imported to MIMICS 10.01® software (Materialise N.V.), and each FS volume was calculated in mm3. There was an absence of significant difference between right and left FS volume (p = 0.173) and an absence of correlation between age and FS volume (Pearson's test; p = 0.705). Sexual dimorphism was significantly different (p = 0.001). However, the most discriminant datum for determining sex was found to be the total FS volume (sum of an individual's right and left FS volumes) with linear discriminant Fisher's function coefficients of ?2.759 for the male group and ?1.275 for the female group. With this model, 72.5% of our sample was correctly classified according to sex.  相似文献   
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