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91.
Steven W. Lindsay Thomas C. Lindsay Jessica Duprez Martin J. R. Hall Brenda A. Kwambana Musa Jawara Ikumapayi U. Nurudeen Neneh Sallah Nigel Wyatt Umberto D'Alessandro Margaret Pinder Martin Antonio 《PLoS neglected tropical diseases》2012,6(11)
Background
Chrysomya spp are common blowflies in Africa, Asia and parts of South America and some species can reproduce in prodigious numbers in pit latrines. Because of their strong association with human feces and their synanthropic nature, we examined whether these flies are likely to be vectors of diarrheal pathogens.Methodology/Principal Findings
Flies were sampled using exit traps placed over the drop holes of latrines in Gambian villages. Odor-baited fly traps were used to determine the relative attractiveness of different breeding and feeding media. The presence of bacteria on flies was confirmed by culture and bacterial DNA identified using PCR. A median of 7.00 flies/latrine/day (IQR = 0.0–25.25) was collected, of which 95% were Chrysomya spp, and of these nearly all were Chrysomya putoria (99%). More flies were collected from traps with feces from young children (median = 3.0, IQR = 1.75–10.75) and dogs (median = 1.50, IQR = 0.0–13.25) than from herbivores (median = 0.0, IQR = 0.0–0.0; goat, horse, cow and calf; p<0.001). Flies were strongly attracted to raw meat (median = 44.5, IQR = 26.25–143.00) compared with fish (median = 0.0, IQR = 0.0–19.75, ns), cooked and uncooked rice, and mangoes (median = 0.0, IQR = 0.0–0.0; p<0.001). Escherichia coli were cultured from the surface of 21% (15/72 agar plates) of Chrysomya spp and 10% of these were enterotoxigenic. Enteroaggregative E. coli were identified by PCR in 2% of homogenized Chrysomya spp, Shigella spp in 1.4% and Salmonella spp in 0.6% of samples.Conclusions/Significance
The large numbers of C. putoria that can emerge from pit latrines, the presence of enteric pathogens on flies, and their strong attraction to raw meat and fish suggests these flies may be common vectors of diarrheal diseases in Africa. 相似文献92.
InvertNet, one of the three Thematic Collection Networks (TCNs) funded in the first round of the U.S. National Science Foundation's Advancing Digitization of Biological Collections (ADBC) program, is tasked with providing digital access to ~60 million specimens housed in 22 arthropod (primarily insect) collections at institutions distributed throughout the upper midwestern USA. The traditional workflow for insect collection digitization involves manually keying information from specimen labels into a database and attaching a unique identifier label to each specimen. This remains the dominant paradigm, despite some recent attempts to automate various steps in the process using more advanced technologies. InvertNet aims to develop improved semi-automated, high-throughput workflows for digitizing and providing access to invertebrate collections that balance the need for speed and cost-effectiveness with long-term preservation of specimens and accuracy of data capture. The proposed workflows build on recent methods for digitizing and providing access to high-quality images of multiple specimens (e.g., entire drawers of pinned insects) simultaneously. Limitations of previous approaches are discussed and possible solutions are proposed that incorporate advanced imaging and 3-D reconstruction technologies. InvertNet couples efficient digitization workflows with a highly robust network infrastructure capable of managing massive amounts of image data and related metadata and delivering high-quality images, including interactive 3-D reconstructions in real time via the Internet. 相似文献
93.
Umberto Maggi Enzo Andorno Giorgio Rossi Luciano De Carlis Umberto Cillo Fabrizio Bresadola Vincenzo Mazzaferro Andrea Risaliti Paolo Bertoli Dario Consonni Francesco Barretta Tullia De Feo Mario Scalamogna 《PloS one》2012,7(10)
This study is the largest Italian survey on liver retransplantations (RET). Data report on 167 adult patients who received 2 grafts, 16 who received 3 grafts, and one who received 4 grafts over a 11 yr period.There was no statistically significant difference in graft survival after the first or the second RET (52, 40, and 29% vs 44, 36, and 18% at 1,5,and 10 yr, respectively: Log-Rank test, p = 0.30).Survivals at 1, 5, and 10 years of patients who underwent 2 (n = 151) or 3 (n = 15) RETs, were 65, 48,and 39% vs 59, 44, and 30%, respectively (p = 0.59).Multivariate analysis of survival showed that only the type of graft (whole vs reduced) was associated with a statistically significant difference (HR = 3.77, Wald test p = 0. 05); the donor age appeared to be a relevant factor as well, although the difference was not statistically significant (HR = 1.91, Wald test p = 0.08).Though late RETs have better results on long term survival relative to early RETs, no statistically significant difference can be found in early results, till three years after RET.Considering late first RETs (interval>30 days from previous transplantation) with whole grafts the difference in graft survival in RETs due to HCV recurrence (n = 17) was not significantly different from RETs due to other causes (n = 53) (65–58 and 31% vs 66–57 and 28% respectively at 1–5 and 10 years, p = 0.66). 相似文献
94.
95.
When someone is choosing one piece from a bowl full of fruit, many pieces are within reach and visible. Although the desired piece seems to govern the particular pattern and direction of that person's reaching movement, the selection process is not impervious to the presence of task-irrelevant information (i.e. the other fruits). Evidence suggests that the kinematics of reach-to-grasp actions for a desired object integrates the motor features of all the objects which might become potential targets. Transcranial magnetic stimulation (TMS) and motor-evoked potentials (MEPs) were used by us to establish if that motor integration process can be transferred to an onlooker. Our results indicate that observation of hybrid reach-to-grasp movement kinematics is reflected in the observer's pattern of MEP amplitudes. This effect can be defined as a form of motor resonance which operates by 'reading' the kinematics of an observed action. The brain's ability to mirror motor integration processes while observing someone else's action helps an onlooker to understand what the other person is doing and to predict his/her motor alternatives. 相似文献
96.
Donato Traversa Annunziata Giangaspero Umberto Molini Raffaella Iorio Barbara Paoletti Domenico Otranto Carla Giansante 《Applied microbiology》2004,70(7):4367-4370
Chamelea gallina clams collected from the mouths of rivers along the Adriatic Sea (central Italy) were found to harbor Cryptosporidium parvum (genotype 2), which is the lineage involved in zoonotic transmission. The clams were collected from the mouths of rivers near whose banks ruminants are brought to graze. This paper reports the environmental spread of C. parvum in Italy and highlights the fact that genotyping of seaborne Cryptosporidium isolates is a powerful tool with which to investigate the transmission patterns and epidemiology of this microorganism. 相似文献
97.
Muscatello U 《Biochemical and biophysical research communications》2008,369(1):52-56
The object of this paper is to trace the growth of a fundamental problem that for a decade hindered the development of several lines of muscle research: the molecular mechanism that allows and controls contraction and relaxation of muscle fiber. Emphasis is placed on the difficulties to be overcome; thus the paper records not only the achievements and successes, but also the unavoidable failure and disappointments. The account highlights the essential contribution of Setsuro Ebashi to find the solution of the problem. 相似文献
98.
Molecular characteristics of small intestinal and renal brush border thiamin transporters in rats. 总被引:1,自引:0,他引:1
Anna Verri Umberto Laforenza Giulia Gastaldi Marisa Tosco Gianguido Rindi 《Biochimica et biophysica acta》2002,1558(2):187-197
The molecular characteristics of thiamin (T) transport were studied in the small intestinal and renal brush border membrane vesicles of rats, using [(3)H]T at high specific activity. The effects of various chemical modifiers (amino acid blockers) on T uptake were examined and their specificity assessed. Treatment with the carboxylic specific blockers 1-cyclohexyl-3-(2-morpholinoethyl) carbodiimide metho-p-toluene sulfonate, (1-ethyl-3-[3-(dimethylamino)propyl]-carbodiimide hydrochloride and N-ethyl-5-phenylisoaxolium-3'-sulfonate (Woodward's Reagent K) and with the sulfhydryl specific blocker p-chloromercuribenzene sulfonate inhibited T transport in both types of vesicles. Phenylglyoxal, but not ninhydrin, both reagents for arginine residues, and diethylpyrocarbonate, a reagent for histidine residues, specifically decreased T transport only in renal and small intestinal vesicles respectively. Similarly 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole reacted, but not N-acetylimidazole, both of which are reagents for tyrosine residues. However, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole inhibition was aspecific. Acetylsalicylic acid, a reagent for lysine and serine residues, decreased T transport, but the lysine effect was aspecific. Acetylsalicylic acid serine blockage also eliminated T/H(+) exchange in small intestinal vesicles. Taken together, these results suggest that for T transport carboxylic and sulfhydryl groups and serine residues are essential in both renal and small intestinal brush border membrane vesicles. In addition, arginine and histidine residues are also essential respectively for renal and small intestinal transporters. Serine was essential for the T/H(+) antiport mechanism. 相似文献
99.
The self-organization of fluorescent dyes and receptors on a proper template to form an organized assembly is a new strategy for the realization of fluorescence chemosensors. In the assembly, the two subunits do not interact directly and the communication between the bound substrate and the dye is only determined by their spatial closeness ensured by the template. The method is simple and the main advantages are related to the minimization of the synthetic work, the ease of modification and optimization of the sensor, the possibility to tune its properties by the simple adjustment of the components ratio. Self-organizing methodologies can open new perspectives to fluorescence chemosensors, both by allowing a simplified preparation and by opening the way to new and more complex functions. This article deals with this new approach and discusses its evolution, applications, and limitations. 相似文献
100.
P. Pellegrini Anna Maria Berghella T. Del Beato Sergio Cicia Domenico Adorno Carlo Umberto Casciani 《Cancer immunology, immunotherapy : CII》1996,42(1):1-8
Recent theories have established that, during an ongoing immune response, the lymphokines produced by TH1 and TH2 subsets
of CD4+ T cells are critical to the effectiveness of that response. In vivo and in vitro studies have demonstrated that the type
of environmental cytokines plays a determinant role in directing the development of naive T cells into TH1 or TH2 effector
cells. Disregulated expansion of one or other subset may contribute to the development of certain diseases. To establish whether
a similar situation might exist in the cells of the peripheral blood (PBMC) of colorectal cancer patients, we have performed
immunological studies on a group of patients and a group of healthy subjects. We examined the interleukin-2 (IL-2), interferon
γ (IFNγ), IL-4, IL-6 and tumour necrosis factor α levels in serum; the production of IL-4 and IL-2, with and without activating
agents, by PBMC, tumour-draining lymph node lymphocytes and tumour cells; and the proliferative response of PBMC to IL-2,
IL-4 and anti-CD3 monoclonal antibody (anti-CD3), which were variously combined. The data of the present study lead us to
hypothesize that, because of suppressive effects probably due to environmental IL-4, in the peripheral blood of patients there
seems to be a disregulation in the functionality of TH1 and TH2 subsets of CD4+ T cells, with an expansion in TH2 and a malfunction in TH1 cells. Moreover it seems that this disregulation increases with
as the disease progresses through the stages, suggesting that it can be directly implicated in the mechanisms that allow the
tumour to locate and progress in the host.
Received: 27 June 1995 / Accepted: 13 November 1995 相似文献