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961.
A K Huxley R C Froede W H Birkby 《The American journal of forensic medicine and pathology》2001,22(1):51-54
A Hispanic woman, 7 1/4, to 7 1/2 lunar months pregnant, was strangled to death by her common-law husband. After receiving information from an informant, a reporter uncovered the remains of the woman and fetus in a grave in a river bank near Eloy, Arizona. The remains were submitted by local law enforcement officials to the forensic pathologist for medicolegal examination. After this analysis, they were turned over to the consulting forensic anthropologist for positive identification of the mother and for fetal age determination to assess possible viability. During the 1970s and 1980s, viability for a fetus of this age was thought possible, although not probable. Prosecution of the common-law husband on the charge of first-degree murder of his wife was successful, whereas a comparable charge for the fetus was not sought. Many issues are raised, including gestational age estimation in relation to fetal viability. Fetal age is reassessed by means of measurements from diaphyseal lengths. These measurements allowed for comparability of fetal age estimations between published studies, with discussion of changing dates of fetal viability made possible through technologic advances. Because fetal viability changes with these advances, it is necessary to establish and update the guidelines for medicolegal practice. 相似文献
962.
Inks from seven black and eight blue ballpoint pens were separated by a high-performance liquid chromatography (HPLC) method utilizing a photodiode array detection (PDA). A classifier flowchart was designed for the chromatographic data based on the presence or absence of certain peaks at different wavelengths to qualitatively discriminate between the inks. The same data were quantitatively classified by principal components analysis (PCA) to estimate the separation between a pair of classes of ink samples. It was found that the black ballpoint pen inks were discriminated satisfactorily utilizing two-dimensional data of the peak areas and retention times at the optimum wavelengths. The blue pens were discriminated by analyzing the chromatographic data at four different wavelengths simultaneously with a cross-validated PCA. The results of this study indicated that HPLC-PDA coupled with chemometrics could make a powerful discriminating tool for the forensic chemist, especially when analyzing extensive and/or complex data. 相似文献
963.
J M Mandojana S Martin-de las Heras A Valenzuela M Valenzuela J D Luna 《Journal of forensic sciences》2001,46(4):889-892
Morphological methods for age estimation from teeth have been developed and applied to samples without taking the postmortem interval into consideration. We studied differences in morphological age-related changes between fresh extracted teeth and teeth from human skeletal remains in order to develop appropriate dental age estimation methods according to the time after death. Forty-three permanent teeth from dental patients were compared to 37 teeth obtained from human skeletal remains with a postmortem interval from 21 to 37 years. Morphological age-related changes were investigated by measuring variables on intact and half-sectioned teeth. A new computer assisted image analysis procedure to avoid subjectivity was developed to measure variables in sectioned specimens. Dental color, translucency length, attrition, cementum apposition, and secondary dentin showed higher values in teeth from human skeletal remains than in fresh extracted teeth. Variables obtained by morphometric analysis of computer-generated images (tooth length, tooth width, root length, and root area) showed higher values in fresh extracted teeth than in teeth from skeletal remains. The postmortem interval affects age-related morphological changes, and therefore different methods should be used for teeth of unknown postmortem interval. 相似文献
964.
When the anterior thoracic wall is within the hypostatic area, postmortem lividity in the region of the nipples and their immediate vicinity is less intense or absent. Where hypostatic skin haemorrhages (so-called vibices) are present, these are also found outside the areola of the nipple only. This phenomenon is visible not only externally, but is particularly pronounced on the cut surface. A possible explanation may be the different distribution pattern of connective tissue, smooth muscles and blood vessels inside and outside the areola mammae. Based on 13 cases from the forensic autopsy material--mostly drug related deaths--the macromorphological findings and their histological correlates are presented. 相似文献
965.
Fraser AD Zamecnik J Keravel J McGrath L Wells J 《Forensic science international》2001,121(1-2):16-22
The Correctional Service of Canada implemented a urine drug-screening program over 10 years ago. The objective of this report is to describe the program and drug test results in this program for 1999. Offenders in Canadian federal correctional institutions and those living in the community on conditional release were subject to urine drug testing. Urine specimens were collected at correctional facilities and shipped by courier to MAXXAM Analytics Inc. laboratory. All urine specimens were analyzed for amphetamines, cannabinoids, cocaine metabolite (benzoylecgonine), opiates, phencyclidine, benzodiazepines, methyl phenidate, meperidine, pentazocine and fluoxetine by immunoassay screening (homogeneous EIA and ELISA assays) followed by GC-MS confirmation. Ethyl alcohol was analyzed when specifically requested. Alternative screening and confirmation methods with lower cut-off values were used, whenever urine specimens were dilute (creatinine <20mg/dl and specific gravity 相似文献
966.
de Boer D Bosman IJ Hidvégi E Manzoni C Benkö AA dos Reys LJ Maes RA 《Forensic science international》2001,121(1-2):47-56
1-Aryl-piperazine compounds are, depending on their substituents, selective for certain serotonin receptors and together with their easy availability and their so-called legal status, this group of psychoactive compounds are potential designer drugs-of-abuse. Internet in that respect is an important source of information and distribution facilities. Because this development may have consequences for the interpretation of future clinical and forensic toxicological case studies, some analytical aspects of 1-benzyl-piperazine (BZP), 1-[4-methoxyphenyl]-piperazine (pMeOPP) and 1-[3-trifluoromethylphenyl]-piperazine (TFMPP) were studied. BZP was not detected by the AxSYM FPIA technology designed to determine amphetamine-like compounds, but had showed some cross reactivity with EMIT d.a.u.. The cross reactivities at 300 and 12,000ng/ml (RS)-amphetamine equivalents were 0.4 and 1.3%, respectively. Although BZP was not identified directly by the REMEDi HS Drug Profiling System, it can be detected by this HPLC/UV scanning system. Using GC/NPD without derivatisation, BZP, pMeOPP and TFMPP can be analysed for and applying GC/MS without or with acetylation or trifluoroacetylation, these compounds can be identified unambiguously. The usefulness of GC/NPD and GC/MS in this respect was demonstrated by the quantitative and qualitative analysis of the content of a capsule with the synthetic stimulant A2, which proved to contain 86.4mg of BZP. 相似文献
967.
Spectra interference between diquat and paraquat by second derivative spectrophotometry 总被引:1,自引:0,他引:1
A rapid and accurate method, combining solid-phase extraction and second-order derivative spectrophotomety approaches, is developed for the simultaneous determination of diquat (DQ) and paraquat (PQ) in blood, tissue and urine samples. Supernatant resulting from the precipitation of protein (with trichloroacetic acid) in plasma and tissue or Amberlite IRA-401 resin treated urine are passed through a mini-column packed with Wakogel gel (Silica gel). Analytes are then eluted with a non-organic solvent, 0.2mol/l HCl solution containing 2mol/l NH(4)Cl. UV spectrum of the eluent in 220-350nm range provides effective screen to detect the presence of DQ and/or PQ. In the presence of DQ or PQ alone, the analyte present is quantitated by conventional zero- or second-order derivative spectrophotometry. The calibration curve in the 0.1-5.0mg/l range for either analyte obeys Beer's law. When both DQ and PQ are present, their concentrations are determined by the peak amplitudes of their respective second-derivative spectra after the addition of alkaline dithionite reagent. Interference is negligible when the DQ/PQ concentration ratio is within the 5.0-0.2 range.Using a 2-ml of sample size, the detection limits for DQ and PQ in plasma are 0.02 and 0.005mg/l. The corresponding detection limits for urine samples (10ml sample size) are 0.004 and 0.001mg/l. Recoveries of DQ and PQ in triplicate plasma and urine samples spiked with 0.5mg/l of analytes are 93 and 85%. The precision of the proposed method resulting from triplicate study of spiked urine samples varies from 3.2 to 4.6% at 0.5mg/l of DQ and PQ, respectively. 相似文献
968.
969.
Baker AM Keller G Garcia D 《The American journal of forensic medicine and pathology》2001,22(3):285-287
The authors report the case of a 21-year-old man who was killed while duck hunting when a shotgun accidentally discharged, shooting him in the head. The loaded weapon, which had been lying on the ground with the safety off and the muzzle pointed toward a river a few feet away, discharged when a hunting dog stepped on the trigger. Scene investigation confirmed that the victim had been standing in the river, planting decoys, with his head approximately level with the adjacent bank. Autopsy examination and ballistic testing confirmed a range of fire consistent with the witness' statements. Examination of the weapon in question documented a light trigger pull but no mechanical defects. The authors review the epidemiology and causality of hunting accidents and discuss the various safety rules that were violated in this highly unusual case. The importance of a complete death investigation, including autopsy, when dealing with a firearm death is emphasized. 相似文献
970.
To improve the possibilities of delimitating the time of death after longer laytime it was examined if this is possible by immunohistochemical detection of calcitonin. The results show that in our examination material the c-cells of the thyroid glands of up to 4-day-old corpses produce a positive immunoreaction towards calcitonin in all cases whereas none of the corpses older than 13 days show such a reaction. This means that in the case of a negative immunoreaction the time of death can be assumed to lie >4 days before the autopsy. The fact that a negative immunoreaction occurred consistently after 13 days leads to the conclusion that when calcitonin has been stained in a specimen, the death of the respective person must lie a maximum of 12 days earlier, whereby these time-limits may change in considerably different surrounding conditions. 相似文献