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81.
82.
Y-STR haplotype data was obtained using the AmpFlSTR® YFiler? PCR Amplification Kit (Applied Biosystems, Foster City, CA) for 1079 Caucasian and 766 Australian Aboriginal individuals. Haplotype diversity was similar in both populations, however discrimination capacity was higher in Caucasians than Aborigines (0.946 compared to 0.692). Locus DYS385, which was considered as a single locus, was the most diverse marker in both populations (0.836 in Caucasians and 0.905 in Aborigines).PopulationThe South Australian Aboriginal and Caucasian databases were compiled from casework reference profile information held on the South Australian Criminal, Reference and Evidence DNA Database (SACREDD). Ethnicity was assigned based on self-declaration.  相似文献   
83.
84.
A sensitive and rapid method for analysis of phosacetim in rabbit tissues and blood has been developed. It requires extraction from biological materials followed by TLC. The assay allows good reproducibility, high recoveries (about 80%), excellent linearity in the range of 0.1 to 20 micrograms with r equal to 0.999, and a low detection limit, 0.05 microgram. The results from TLC were in conformity with those from HPLC. In addition, the assay was applied to study the distribution of phosacetim in rabbit tissues.  相似文献   
85.
This report documents a case of drug-facilitated sexual assault (DFSA) under the influence of solvents. The victim was a 13-year-old female. Upon contact with law enforcement, she was still confused and could hardly explain the facts. She told authorities that she had been kidnapped 4 h previously when two individuals with covered faces put a cloth soaked in a solvent over her mouth. She spent a few hours in a room, during which she lost consciousness. The girl awakened semi-nude in the street with memory loss. No alcohol was present in the subject's body; no odor of alcohol was detected on the subject's breath. No lesions were observed during a gynecological exam. A blood sample was taken with the intent to investigate the use of chloroform or similar anesthetics. Toxicological analysis of the victim's blood revealed the presence of 7.6 mg/L of benzene, 24.8 mg/L of toluene, and 0.6 mg/L of xylene (mixture of isomers). As for other analytical findings, diazepam (0.02 mg/L) was also found. The aromatic solvents involved in this case were detected using gas chromatography with flame-ionization detection (GC-FID) and confirmed using GC-mass spectrometry (MS) in full scan mode after liquid-liquid extraction of the whole blood sample. Quantitation of the aromatic solvents was carried out using GC-FID. Diazepam was detected using GC with nitrogen-phosphorus detection (NPD) and confirmed using GC-MS with full scan mode after solid-phase extraction of the whole blood sample using Bond-Elut Certify columns. Quantitation of diazepam was carried out using GC-NPD. No other drugs, including ethanol, were detected. Recoveries for benzene, toluene, and xylene (mixture of isomers) in whole blood at 5 mg/L were 89.2%, 90.8%, and 93.4%, respectively. Intraday precisions were 5.3%, 5.0%, and 4.9%, respectively, and interday precisions were 12.1%, 11.6%, and 11.5%, respectively. The limits of detection (LOD) and quantitation (LOQ) were 30 and 100 microg/L, respectively. The linearity of the blood calibration curves was excellent with r(2) values of > 0.999 (range 0.1-10 mg/L). Recovery for diazepam in whole blood at 0.5 mg/L was 88.2% with intraday and interday precisions of 2.0% and 10.8%, respectively. The LOD and LOQ were 6 and 20 microg/L, respectively. The linearity of the blood calibration curve was excellent with r(2) values of > 0.999 (range 0.1-2 mg/L). We want to alert other toxicologists about new or unexpected products that should be taken into account when the surreptitious use of substances in DFSA is suspected.  相似文献   
86.
The injection of cadaver brains is invaluable for anatomic study, but cadavers that have been properly handled are not easy to obtain. A large number of cadavers pass through forensic departments around the world, and these cadavers could provide hundreds of research specimens, though they remain in the forensic unit for only a short time. The injection of a silicone mixture that quickly solidifies during autopsy would provide greater numbers of fresh specimens for study. The authors describe a technique for injecting a self-curing silicone mixture that can be used on autopsy specimens in a forensic unit. This technique does not interfere with routine autopsy findings. We describe the preparation of the mixture and autopsy specimens, the injection process, and the method for removing injected brains from cadavers. The solidifying process took a 1-h duration in this injection method and was in accord with autopsy procedure. The arterial bed was satisfactorily filled, and even small perforating branches and pial anastomoses were well demonstrated. Injecting autopsy specimens with the quick-solidifying silicone mixture allows anatomical studies of specimens even from cadavers admitted to forensic departments for only a short time. This method can provide neurosurgery laboratories with sufficient numbers of specimens appropriate for various studies.  相似文献   
87.
Interest in the development of polymorphic short tandem repeat (STR) markers unlinked to the CODIS loci is growing among forensic practitioners. We developed a multiplex system in which14 autosomal STR (D3S1744, D4S2366, D8S1110, D12S1090, D13S765, D14S608, Penta E, D17S1294, D18S536, D18S1270, D20S470, D21S1437, Penta D, and D22S683) could be amplified in one single polymerase chain reaction. DNA samples from 572 unrelated Taiwanese Han subjects were analyzed using this 14 STR multiplex system. Thirty parent–child pairs of parentage testing cases with a combined paternity index (CPI) below 1,000 and 32 parent–child pairs with single-step mutations found in AmpFℓSTR Identifiler loci were also recruited for validation of the newly developed system. DNA sequencing was performed for novel STRs and novel alleles found in these subjects. The distributions of allelic frequencies for these autosomal STRs and sequence data, allele nomenclature for the STRs, and forensic parameters are presented. The discrimination power in our multiplex loci ranged from 0.6858 (D18S536) to 0.9168 (Penta E), with a combined discrimination power of 0.999999999. It provides additional power to distinguish the possible single-step mutations in parent–child pairs and improves the ability to prove parentage by increasing the CPI. The combined power of exclusion of these 14 loci in Taiwanese Han in this study was 0.9999995913. In conclusion, this 14-autosomal STRs multiplex system provides highly informative STR data and appears useful in forensic casework and parentage testing.  相似文献   
88.
BackgroundResults on myocardial substrate metabolism in the failing heart have been contradictory. Insulin resistance, a common comorbidity in heart failure patients, and medical therapy may modify myocardial metabolism in complex fashions. Therefore, we characterized myocardial oxidative and free fatty acid (FFA) metabolism in patients with idiopathic dilated cardiomyopathy (IDCM) and investigated the contributions of insulin resistance and β-blocker therapy.Methods and ResultsNineteen patients with IDCM (age 58 ± 8 years, ejection fraction 33 ± 8.8%) and 15 healthy controls underwent examination of myocardial blood perfusion, oxidative and FFA metabolism using positron emission tomography and [15O]H2O, [11C]acetate and [11C]palmitate, respectively. Echocardiography was used to assess myocardial function, work, and efficiency of forward work. Insulin resistance was calculated using the homeostasis model assessment index (HOMA index) and the degree of β-blockade was estimated with a β-adrenoceptor occupancy test. IDCM patients were characterized by decreased cardiac efficiency (35 ± 2 versus 57 ± 12 mm Hg·L·g−1, P < .0001) and reduced myocardial FFA uptake (5.5 ± 2.0 versus 6.4 ± 1.2 μmol·100 g−1·min−1, P < .05), but the FFA β-oxidation rate constant was not changed. In the patients, myocardial FFA uptake was inversely associated with left ventricular (LV) ejection fraction (r = −0.63, P < .01), indicating that further depression of LV function induces an opposite switch to greater FFA uptake. The FFA β-oxidation rate constant correlated positively with the HOMA index (r = 0.53, P < .05). In patients on β-1 selective β-blockers, β-1 adrenoceptor occupancy correlated inversely with LV work, oxidative metabolism, and FFA uptake; similar relationships were not found in patients on nonselective β-blocker.ConclusionsMyocardial FFA metabolism is reduced in patients with IDCM. However, when LV function is further depressed and insulin resistance manifested, myocardial FFA uptake and oxidation are, in turn, upregulated. These findings may partly explain the discrepancies between previous studies about cardiac metabolism in heart failure.  相似文献   
89.

Aim

To analyze two phenotype characteristics – eye and hair color – using single-nucleotide polymorphisms (SNPs) and evaluate their prediction accuracy in Slovenian population.

Methods

Twelve SNPs (OCA2 – rs1667394, rs7170989, rs1800407, rs7495174; HERC2 – rs1129038, rs12913832; MC1R – rs1805005, rs1805008; TYR – rs1393350; SLC45A2 – rs16891982, rs26722; SLC24A5 – rs1426654) were used for the development of a single multiplex assay. The single multiplex assay was based on SNaPshot chemistry and capillary electrophoresis. In order to evaluate the accuracy of the prediction of eye and hair color, we used the logistic regression model and the Bayesian network model, and compared the parameters of both.

Results

The new single multiplex assay displayed high levels of genotyping sensitivity with complete profiles generated from as little as 62 pg of DNA. Based on a prior evaluation of all SNPs in a single multiplex, we focused on the five most statistically significant in our population in order to investigate the predictive value. The two prediction models performed reliably without prior ancestry information, and revealed very good accuracy for both eye and hair color. Both models determined the highest predictive value for rs12913832 (P < 0.0001), while the other four SNPs (rs1393350, rs1800407, rs1805008, and rs7495174) showed additional association for color prediction.

Conclusion

We developed a sensitive and reliable single multiplex genotyping assay. More samples from different populations should be analyzed before this assay could be used as one of the supplemental tools in tracing unknown individuals in more complicated crime investigations.Height, face structure, pigmentation of the eye, hair, and skin, the presence of freckles, and male baldness make up human externally visible characteristics (EVC). To be able to predict eye and hair color based solely on biological material left behind at a crime scene or obtained from dismembered missing persons, or even of disaster victims, is one of the major expectations from the routine forensic work in the near future (1). However, genetic understanding of human appearance is still in its infancy, mainly due to the fact that all EVCs are polygenic traits. This means that yields from a large number of different genes and the expression of these genes are further influenced by mutual interactions and environmental interactions (2). Above all, molecular mechanisms and functional protein assays must also be considered in order to really understand how allelic variation in pigmentation genes could result in such a diversity of phenotypes in different human populations (3). The human eye (iris) and hair color are one of the most highly polymorphic phenotypes in people of European origin. The non-brown iris colors and red hair are generally features of European origin resulting from positive selection in early European history. There are several hypotheses for positive selection that mainly occurred in the Baltic region and Northern Europe. These are most likely: UV exposure causing skin cancer, vitamin D deficiency, and even sexual selection (4,5). Most EVCs are complex traits with many genes and single nucleotide polymorphism (SNP) variations, so the right combination of SNPs is crucial for the correct prediction of eye and hair color. Several genome-wide association studies (GWAS) for pigmentation have revealed that SNPs within the HERC2, OCA2, MC1R, SLC24A5, SLC45A2, TYR, and ASIP (4,6-16) genes were most strongly associated with eye and hair color in European populations. The latest data have shown that the main iris color variation is associated with a highly evolutionarily preserved region in the HERC2 gene or within the short sequence between the HERC2 and OCA2 genes. It is assumed that these regions represent a regulatory region controlling the constitutive expression of OCA2 (4,11,12). As for iris color, it has also been explained that red hair color is mainly associated with polymorphisms in the MC1R gene (13,17). On the other hand, the variations of genes such as SLC24A5, SLC45A, HERC2, and ASIP seem to be responsible for influencing the shades of hair color from blond to black (18,19).In order to correctly predict human eye and hair color from genetic data for the Slovenian population, we compared two alternative prediction models that are nowadays used most often in this field of forensics – the Bayesian network model and the logistic regression model. These models were developed and compared on the basis of the informative SNPs selected from our single multiplex assay.  相似文献   
90.
Background Little is known about client characteristics that are related to outcome during inpatient treatment of adults with mild intellectual disability (ID) and severe behavioural problems. Method We explored variables that were related to a change in behavioural problems in 87 individuals with mild ID during inpatient treatment in facilities for adults with mild ID and severe behavioural problems. Emotional and behavioural problems were measured using the Adult Behaviour Checklist (ABCL) and relationships between a change in ABCL total scores and other variables (e.g. age, adaptive skills, and presence of personality disorder) were explored. Results For the sample as a whole, we found a decrease in emotional and behavioural problems within a 1‐year period of inpatient treatment (following a 3‐month observation and diagnostic period). Male clients, clients without a personality disorder classification, and/or clients who showed more improvement in adaptive and social functioning, showed a larger decrease in emotional and behavioural problems than other clients. Gender and personality disorder classification appeared to be the most important predictive factors. Conclusion Clients with mild ID and severe behavioural problems may benefit from inpatient treatment. Those with a personality disorder and/or female clients may benefit less from such a program. Results of such studies may have consequences for service provision and management. Limitations of this study were the lack of data on the quantity and quality of the treatment package and unknown reliability and validity of Axis‐I and personality disorder diagnoses.  相似文献   
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