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901.
Enrique Blanco Gonzalez Tomoya Murakami Yuki Teshima Kouji Yoshioka Dal-Sang Jeong Tetsuya Umino 《Ichthyological Research》2009,56(1):87-91
We developed four microsatellite DNA loci to test for multiple paternity of black rockfish, Sebastes inermis, from the Seto Inland Sea of Japan. All loci showed a high degree of polymorphism (number of alleles per locus = 10–14, expected
heterozygosity = 0.80) and discriminating power (probability of identity index = 3.71 × 10−6, exclusion probability = 0.999) in unrelated wild specimens (n = 32). Genotypic assignment of five dams (109–220 mm in total length) and 50 embryos from each dam (n = 50) indicated that four dams were mated with a single sire. Only for one dam and three of her embryos we could not exclude
multiple paternity. 相似文献
902.
Muhammad Wasif Saif Ifigenia Tzannou Nektaria Makrilia Kostas Syrigos 《The Yale journal of biology and medicine》2010,83(2):53-65
PET/CT is a relatively new imaging technology, whose undoubted advantages are valuable in clinical oncology as well as in all fields of diagnosis, staging, and treatment. The hardware combination of anatomy and function has been the true evolution in imaging. PET using 18F-fluorodeoxyglucose (FDG) is increasingly used for the staging of solid malignancies, including colon, lung, etc., but anatomic information is limited. Integrated PET/CT enables optimal anatomic delineation of PET findings and identification of FDG-negative lesions on computed tomography (CT) images and might improve preoperative staging. However, controversy still exists in relation to the application of PET/CT in clinical practice, mainly because of its high cost. It is evident that apart from additional costs, potential savings also are associated with PET/CT as a result of avoiding additional imaging examinations or invasive procedures and by helping clinicians make the optimum treatment decisions. The authors review the literature on the role of PET/CT in management of various tumors and discuss the medicoeconomic usefulness. 相似文献
903.
Beatriz E. Perazzi Claudia I. Menghi Enrique F. Coppolillo Claudia Gatta Martha Cora Eliseth Ram��n A. de Torres Carlos A. Vay Angela M. R. Famiglietti 《The Korean journal of parasitology》2010,48(1):61-65
The objectives of this study were to conduct a prevalence survey of trichomoniasis in pregnant women and to evaluate the utility of different methods for its diagnosis. A total of 597 vaginal exudates from pregnant women who were examined at the Hospital de Clinicas in Buenos Aires, Argentina from 1 August 2005 to 31 January 2007, were prospectively and consecutively evaluated. The investigation of Trichomonas vaginalis was made by different microscopic examinations, and culture on liquid medium. The sensitivity and specificity of the microscopic examinations were assessed considering culture on liquid medium as the "gold standard". The prevalence of T. vaginalis obtained by culture on liquid medium was 4.0% (24/597). The prevalence of T. vaginalis obtained by direct wet smear, prolonged May-Grunwald Giemsa staining, and sodium acetate-formalin (SAF)/methylene blue staining-fixing technique was 1.8%, 2.3% and 2.5%, respectively. The sensitivity of the direct wet smear was 45.8%, that of the prolonged May-Grunwald Giemsa staining was 58.3%, and that of the SAF/methylene blue method was 62.5%. Considering the 3 microscopic examinations altogether, the sensitivity rose to 66.7% and the specificity was 100% for all of them. This is the first time that the prevalence data of T. vaginalis by culture in pregnant women are published in Argentina. Due to the low sensitivity obtained by microscopy in asymptomatic pregnant women, the use of the liquid medium is recommended during pregnancy, in order to provide an early diagnosis and treatment. 相似文献
904.
microRNA(miRNA)是一类自然形成的非编码小RNA,不少miRNA分子已被证实与癌症的生成有关联。近期的研究发现人血清中稳定存在一定水平的miRNA,并且血清miRNA表达谱的变化与多种肿瘤的发生、发展具有明确的相关性,说明血清miRNA可以作为肿瘤临床诊断和预后评估的分子标志物。因此,特定的血清miRNA表达谱可以构成识别癌症与其他疾病的"指纹",为癌症及其他疾病的诊断提供一种新的非侵入性的检测方法,同时,该技术还可用于肿瘤分类、预后判断、手术疗效监测及疾病复发预测等领域,并可能带来未来临床医学上的变革。 相似文献
905.
A new method for the early diagnosis of brain edema/brain swelling. An experimental study in rabbits
The aim of the present work is to develop a non-destructive, non-invasive technique for the early diagnosis of an oncoming brain edema based on the variation of vibration characteristics of the head system (i.e. eigenfrequency spectrum and modal damping). Besides the theoretical model that supports the basic principle, the proposed technique has been verified experimentally in animal tests. The advantage of such an approach is that the relative information is available well in advance an increase of intracranial pressure is detected. The uncontrolled intracranial hypertension is associated with increased mortality or vegetative state in head trauma. Traumatic lesions located on temporal lobe render particularly impeding the transtendorial herniation. From the medical point of view, intracranial pressure (ICP) monitoring represents an effective way for early consideration of neurological decompensation in various neurosurgical conditions particularly in the head-injured setting. However, the use of ICP monitoring is not an effective way of brain edema detection, since ICP increase very often causes irreversible problems to the patient's brain. Therefore, the determination of an earlier, less invasive and more sensitive indicator of the oncoming intracranial hypertension and of the impeding neurological deterioration is of profound importance.
The present work aims at experimental verification of both eigenfrequency shifting and modal damping increase of the spectral response of the head system of rabbits, wherever a mass increase in the content of cranial shell appears. The conducted analysis concludes that the eigenfrequency spectrum and its modal damping characteristics are sufficiently sensitive parameters in order to characterize mass increase in the cranial shell.
Therefore the combination of both the above parameters could be used with confidence for the early diagnosis of brain edema. 相似文献
906.
Chakravorty S Pathak D Dudeja M Haldar S Hanif M Tyagi JS 《FEMS microbiology letters》2006,257(2):306-311
This study was designed to assess the vital issue of gene target length and PCR assay performance in relation to the detection of Mycobacterium tuberculosis in clinical specimens. Two PCR assays that amplify fragments of varying lengths from the devR gene of M. tuberculosis were evaluated. Using M. tuberculosis DNA the 'short-length' PCR assay detected 250-500 genome equivalents vs. 500-1,000 genome equivalents by the 'long-length' assay. In comparison to a highly sensitive smear microscopy test (universal sample processing smear), the sensitivity of the 'short-length' assay was 97.8% vs. 69.9% of the 'long-length' assay in sputum specimens (n=506) from patients being evaluated for a possible diagnosis of tuberculosis. The 27.9% absolute increase in sensitivity was statistically significant (P<0.001). Our results indicate that in a clinical setting when all other conditions are equal, the amplification of a shorter gene fragment of devR increases the sensitivity and efficiency of the PCR assay in spite of using a single copy gene as target. 相似文献
907.
908.
Modra L 《Bioethics》2006,20(5):254-263
Research groups around the world are developing non‐invasive methods of prenatal genetic diagnosis, in which foetal cells are obtained by maternal blood test. Meanwhile, an increasing number of genetic tests are sold directly to the public. I extrapolate from these developments to consider a scenario in which PNGD self‐testing kits are sold directly to the public. Given the opposition to over‐the‐counter genetic tests and the continuing controversy surrounding PNGD, it is reasonable to expect objections to PNGD self‐testing kits. I focus on one potential objection, that PNGD self‐testing kits would undermine the autonomy of potential test subjects. More specifically, that ‘direct to the public’ PNGD would fail to ensure that consumers exercise autonomy in the following PNGD‐related choices:
- ? Should I use PNGD?
- ? Based on the results of the PNGD test, should I continue or terminate my pregnancy?
909.
Biomarkers in cancer screening, research and detection: present and future: a review 总被引:1,自引:0,他引:1
Biomarkers provide a powerful and dynamic approach to understanding the spectrum of malignancies with applications in observational and analytic epidemiology, randomized clinical trials, screening, diagnosis and prognosis. Defined as alterations in the constituents of tissues or body fluids, these markers offer a means for homogeneous classification of a disease and risk factor, and they can extend one's basic information about the underlying pathogenesis of disease. The goals in cancer research include finding biomarkers that can be used for the early detection of cancers, design individual therapies, and to identify underlying processes involved in the disease. Because so many myriad processes are involved in the diseased states, the goal is similar to 'finding a needle in a haystack'. However, the development of many -omic technologies, such as genomics and proteomics, has allowed us to monitor a large number of key cellular pathways simultaneously. This has enabled the identification of biomarkers and signalling molecules associated with cell growth, cell death and cellular metabolism. These are also facilitating in monitoring the functional disturbance, molecular and cellular damage, and damage response. This brief review describes the development of biomarkers in cancer research and detection with emphasis on different proteomic tools for the identification and discovery of new biomarkers, different clinical assays to detect various biomarkers in different specimens, role of biomarkers in cancer screening and last but not the least, the challenges in this direction of cancer research. 相似文献
910.
Coletta-Filho HD Takita MA Souza AA Neto JR Destéfano SA Hartung JS Machado MA 《Journal of applied microbiology》2006,100(2):279-285
AIMS: To have a PCR-based detection method for Xanthomonas axonopodis pv. citri (Xac) using primers designed in a specific region of its genome. METHODS AND RESULTS: A Xac-specific region was identified inside the rpf gene cluster of strain IAPAR 306 in an analysis of its complete genomic sequence. Two primers were designed, Xac01 and Xac02, which, when used in a standard PCR assay, direct the amplification of a 581 bp fragment from DNA of strains belonging to Xac from different regions around the world including unusual American and Asian strains. This product was not observed when DNA from strains of the closely related X. a. aurantifolli and X. a. citrumelo were used as templates. Extracts prepared from 28 xanthomonads of other species, and epiphytic bacteria isolated from citrus also failed to produce products with these primers. Amplification was obtained from cells grown in vitro, from extracts of both fresh and dried citrus canker lesions and from washes of inoculated but asymptomatic leaf surfaces. In sensitivity tests, this PCR technique detected as few as 100 cells. CONCLUSIONS: Primers Xac01 and Xac02 provide specific and sensitive detection of Xac in all citrus tissues where the pathogen is found. SIGNIFICANCE AND IMPACT OF THE STUDY: This PCR-based diagnostic test is suitable for monitoring asymptomatic plants in areas where the bacteria is endemic, in plant quarantine and regulatory situations, and also for obtaining an accurate diagnosis in a very short time. These are important characteristics for any assay to be used for the management of citrus canker disease. 相似文献