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61.
Björn Andersson Gunnel Hellgren Andreas FM Nierop Ze'ev Hochberg Kerstin Albertsson-Wikland 《Proteome science》2009,7(1):40-12
Background
The broad range in growth observed in response to growth hormone (GH) treatment is mainly caused by individual variations in both GH secretion and GH sensitivity. Individual GH responsiveness can be estimated using evidence-based models that predict the response to GH treatment; however, these models can be improved. High-throughput proteomics techniques can be used to identify proteins that may potentially be used as variables in such models in order to improve their predictive ability. Previously we have reported that proteomic analyses can identify biomarkers that discriminate between short prepubertal children with idiopathic short stature (ISS) who show good or poor growth in response to GH treatment. In this study we used a pharmaco-proteomic approach to identify novel factors that correlate with the growth response to GH treatment in prepubertal children who are short due to GH deficiency or ISS. The study included 128 short prepubertal children receiving GH treatment, of whom 39 were GH-deficient and 89 had ISS. Serum protein expression profiles at study start and after 1 year of GH treatment were analyzed using SELDI-TOF. Cross-validated regression and random permutation analyses were performed to identify significant correlations between protein expression patterns and the 2-year growth response to GH treatment. 相似文献62.
Elisa Cannizzo Aliyah R. Sohani Judith A. Ferry Ephraim P. Hochberg Michael J. Kluk Michelle E. Dorn Craig Sadowski Janessa J. Bucci Adam M. Ackerman Janina A. Longtine Giovanni Carulli Frederic I. Preffer 《Journal of Hematopathology》2009,2(3):163-170
Multiple malignancies may occur in the same patient, and a few reports describe cases with multiple hematologic and non-hematologic neoplasms. We report the case of a patient who showed the sequential occurrence of four different lymphoid neoplasms together with a squamous cell carcinoma of the lung. A 62-year-old man with adenopathy was admitted to the hospital, and lymph node biopsy was positive for low-grade follicular lymphoma. He achieved a partial remission with chemotherapy. Two years later, a PET-CT scan showed a left hilar mass in the lung; biopsy showed a squamous cell carcinoma. Simultaneously, he was diagnosed with diffuse large B cell lymphoma in a neck lymph node; after chemo- and radiotherapy, he achieved a complete response. A restaging PET-CT scan 2 years later revealed a retroperitoneal nodule, and biopsy again showed a low-grade follicular lymphoma, while a biopsy of a cutaneous scalp lesion showed a CD30-positive peripheral T cell lymphoma. After some months, a liver biopsy and a right cervical lymph node biopsy showed a CD30-positive peripheral T cell lymphoma consistent with anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. Flow cytometry and cytogenetic and molecular genetic analysis performed at diagnosis and during the patient’s follow-up confirmed the presence of two clonally distinct B cell lymphomas, while the two T cell neoplasms were confirmed to be clonally related. We discuss the relationship between multiple neoplasms occurring in the same patient and the various possible risk factors involved in their development. 相似文献
63.
Courtney L. Olson Luz P. Acosta Natasha S. Hochberg Remigio M. Olveda Mario Jiz Stephen T. McGarvey Jonathan D. Kurtis David C. Bellinger Jennifer F. Friedman 《PLoS neglected tropical diseases》2009,3(10)
Background
Many studies have addressed the relationship between iron deficiency anemia (IDA) and cognitive impairment, but none have evaluated the role of non-iron deficiency anemia (NIDA). One of the main causes of NIDA in developing countries is AI, largely due to infectious diseases, whereby iron is shunted away from bio-available forms to storage forms, making it less accessible for use by host tissues. The objective of this study was to determine the effect of NIDA, due largely to AI in this context, on cognitive function after adjustment for potential confounders.Methodology
This cross-sectional study was conducted in Leyte, The Philippines among 322 children ages 7–18 years. Blood samples were collected and analyzed at the time of cognition testing. Three stool samples were collected and evaluated by the Kato Katz method for quantitative assessment for Schistosoma japonicum and geo-helminth infection. Socio-economic status (SES) was evaluated by survey. Linear regression models were used to quantify the adjusted relationship between performance in different cognitive domains and both IDA and NIDA.Principal Findings
After adjusting for age, sex, SES and nutritional status, children in the NIDA had lower scores on the PNIT (P = <0.05) and the WRAML memory domain (P<0.05) compared to children in the non-anemic group. Children in the IDA had lower performance on the PNIT compared to the non-anemic group after controlling for potential confounders (P<0.05).Conclusions
NIDA, predominantly due to AI in this context, was related to lower performance on two tests of cognitive function. This is likely due to decreased delivery of iron to host tissues in this context, including the CNS. 相似文献64.
A. B. Duncan E. Dusi F. Jacob J. Ramsayer M. E. Hochberg O. Kaltz 《Journal of evolutionary biology》2017,30(1):55-65
Antagonistic coevolution between hosts and parasites is a key process in the genesis and maintenance of biological diversity. Whereas coevolutionary dynamics show distinct patterns under favourable environmental conditions, the effects of more realistic, variable conditions are largely unknown. We investigated the impact of a fluctuating environment on antagonistic coevolution in experimental microcosms of Pseudomonas fluorescens SBW25 and lytic phage SBWΦ2. High‐frequency temperature fluctuations caused no deviations from typical coevolutionary arms race dynamics. However, coevolution was stalled during periods of high temperature under intermediate‐ and low‐frequency fluctuations, generating temporary coevolutionary cold spots. Temperature variation affected population density, providing evidence that eco‐evolutionary feedbacks act through variable bacteria–phage encounter rates. Our study shows that environmental fluctuations can drive antagonistic species interactions into and out of coevolutionary cold and hot spots. Whether coevolution persists or stalls depends on the frequency of change and the environmental optima of both interacting players. 相似文献
65.
Castellanos-Martinez S Gómez MC Hochberg FG Gestal C Furuya H 《The Journal of parasitology》2011,97(2):265-269
A new species of dicyemid mesozoan is described from Octopus hubbsorum Berry, 1953, collected in the south of Bahia de La Paz, Baja California Sur, México. Dicyema guaycurense n. sp. is a medium-size species that reaches about 1,600 μm in length. It occurs in folds of the renal appendages. The vermiform stages are characterized as having 22 peripheral cells, a conical calotte, and an axial cell that extends to the base of the propolar cells. Infusoriform embryos consist of 39 cells; 1 nucleus is present in each urn cell and the refringent bodies are solid. This is the first of a dicyemid species from a host collected in the Gulf of California. 相似文献
66.
Clara Torres-Barceló Flor I. Arias-Sánchez Marie Vasse Johan Ramsayer Oliver Kaltz Michael E. Hochberg 《PloS one》2014,9(9)
The evolution of antibiotic resistance in bacteria is a global concern and the use of bacteriophages alone or in combined therapies is attracting increasing attention as an alternative. Evolutionary theory predicts that the probability of bacterial resistance to both phages and antibiotics will be lower than to either separately, due for example to fitness costs or to trade-offs between phage resistance mechanisms and bacterial growth. In this study, we assess the population impacts of either individual or combined treatments of a bacteriophage and streptomycin on the nosocomial pathogen Pseudomonas aeruginosa. We show that combining phage and antibiotics substantially increases bacterial control compared to either separately, and that there is a specific time delay in antibiotic introduction independent of antibiotic dose, that minimizes both bacterial density and resistance to either antibiotics or phage. These results have implications for optimal combined therapeutic approaches. 相似文献
67.
Macrodasyidan gastrotrichs are hermaphrodites with complex reproductive organs that function in sperm transfer and receipt, but homology among the organs of members of different clades remains undetermined, as does a broader understanding of evolutionary trends in the reproductive biology of macrodasyidans. In this study, we investigate the evolution of reproduction in Urodasys, a clade of 15 macrodasyidan species that shows variability in reproductive mode (hermaphroditic and parthenogenetic) and sexual anatomy. We use partial 18S rDNA sequence data from 30 specimens representing five described species, sequence data from one undescribed species in GenBank, and sequence data from a potentially new species found at Capron Shoal, Florida, to gain insight into the phylogeny of the clade and clarify evolutionary trends in reproductive modality. Based on a total of 33 specimens of seven potential species, we found that members of Urodasys can be separated into three clades reflective of different reproductive modalities: Clade I, species with paired male and female gonads but without accessory sexual organs; Clade II, species with a single left testis, paired ova, and accessory organs including a sclerotic stylet; and Clade III, parthenogenetic species without testes or accessory organs. In addition, we find that the potentially new species from Florida can form spermatophores, a condition shared with another species in Clade I. Herein, we describe this novel spermatophore‐bearing species and discuss the significance of spermatophore formation in the genus. 相似文献
68.
Spectral discrimination of coral reef benthic communities 总被引:8,自引:0,他引:8
Effective identification and mapping of coral reef benthic communities using high-spatial and -spectral resolution digital
imaging spectrometry requires that the different communities are distinguishable by their spectral reflectance characteristics.
In Kaneohe Bay, Oahu, Hawaii, USA, we collected in situ a total of 247 spectral reflectances of three coral species (Montipora capitata, Porites compressa, Porites lobata), five algal species (Dictyosphaeria cavernosa, Gracilaria salicornia, Halimeda sp., Porolithon sp., Sargassum echinocarpum) and three sand benthic communities (fine-grained carbonate sand, sand mixed with coral rubble, coral rubble). Major reflectance
features were identified by peaks in fourth derivative reflectance spectra of coral (at 573, 604, 652, 675 nm), algae (at
556, 601, 649 nm) and sand (at 416, 448, 585, 652, 696 nm). Stepwise wavelength selection and linear discriminant function
analysis revealed that spectral separation of the communities is possible with as few as four non-contiguous wavebands. These
linear discriminant functions were applied to an airborne hyperspectral image of a patch reef in Kaneohe Bay. The results
demonstrate the ability of spectral reflectance characteristics, determined in situ, to discriminate the three basic benthic
community types: coral, algae and sand.
Accepted: 12 January 2000 相似文献
69.
70.
Although studies of interspecific competition have traditionally been concerned with interactions between closely related species, ecological systems teem with examples of competition between representatives not only from different phyla, but even from different kingdoms. Indeed, inter-kingdom competition may be one of the commonest forms of interaction in nature; particularly prevalent are competitive interactions for shared hosts between insect parasitoids and pathogens from four other kingdoms. Ecologists have barely started to explore the ecological and evolutionary implications of interkingdom competition. 相似文献