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381.
Acromegaly is associated with significant morbidity and mortality if it is not appropriately treated. In addition to insulin-like growth factor 1 and growth hormone normalization as well as tumor shrinkage, the treatment goals include relieving symptoms, managing complications, and improving patients’ quality of life. Surgical resection is a first-line treatment option for most patients, with few being pretreated preoperatively with medications. Somatostatin receptor ligands (SRLs), injectable and, more recently, oral capsules, have been the cornerstone of first-line medical therapy for persistent disease. However, several factors, including sparsely granulated adenomas, absent or low somatostatin receptor status, T2-hyperintensity imaging, young age, and aryl hydrocarbon receptor-interacting protein mutations, can predict first-generation SRL resistance. Patients with these characteristics may be better candidates for the growth hormone receptor antagonist pegvisomant, or in cases of large tumors, the second-generation SRL pasireotide. Combination therapy should be further pursued in patients who remain biochemically uncontrolled or have a high remnant tumor after monotherapy. An efficacious and cost-effective pegvisomant dose-sparing effect of SRLs when used in combination has been demonstrated. With such a wide array of medical treatment options, it is becoming increasingly important to tailor treatment to patients’ unique characteristics and preferences, with a goal of personalizing management to achieve high-quality outcomes. 相似文献
382.
《Journal of molecular biology》2022,434(9):167529
Missense variants are alterations to protein coding sequences that result in amino acid substitutions. They can be deleterious if the amino acid is required for maintaining structure or/and function, but are likely to be tolerated at other sites. Consequently, missense variation within a healthy population can mirror the effects of negative selection on protein structure and function, such that functional sites on proteins are often depleted of missense variants. Advances in high-throughput sequencing have dramatically increased the sample size of available human variation data, allowing for population-wide analysis of selective pressures. In this study, we developed a convenient set of tools, called 1D-to-3D, for visualizing the positions of missense variants on protein sequences and structures. We used these tools to characterize human homologues of the ARID family of gene regulators. ARID family members are implicated in multiple cancer types, developmental disorders, and immunological diseases but current understanding of their mechanistic roles is incomplete. Combined with phylogenetic and structural analyses, our approach allowed us to characterise sites important for protein-protein interactions, histone modification recognition, and DNA binding by the ARID proteins. We find that comparing missense depletion patterns among paralogs can reveal sub-functionalization at the level of domains. We propose that visualizing missense variants and their depletion on structures can serve as a valuable tool for complementing evolutionary and experimental findings. 相似文献
383.
Summary The upper thermal limit for maintenance of eleven mosquito cell lines was studied. Although most cell lines could be grown
at 32°C to 34°C,Anopheles stephensi cell line could be maintained at 37°C. At higher temperatures initial growth rate was higher, but yield of cells after about
a week of incubation was lower than at the standard temperature (28°C). Replication of several flaviviruses inAedes albopictus cell cultures adapted to 34.5°C was faster, and viral titers were higher than at 28°C. 相似文献
384.
Understanding and predicting how adaptation will contribute to species' resilience to climate change will be paramount to successfully managing biodiversity for conservation, agriculture, and human health‐related purposes. Making predictions that capture how species will respond to climate change requires an understanding of how key traits and environmental drivers interact to shape fitness in a changing world. Current trait‐based models suggest that low‐ to mid‐latitude populations will be most at risk, although these models focus on upper thermal limits, which may not be the most important trait driving species' distributions and fitness under climate change. In this review, we discuss how different traits (stress, fitness and phenology) might contribute and interact to shape insect responses to climate change. We examine the potential for adaptive genetic and plastic responses in these key traits and show that, although there is evidence of range shifts and trait changes, explicit consideration of what underpins these changes, be that genetic or plastic responses, is largely missing. Despite little empirical evidence for adaptive shifts, incorporating adaptation into models of climate change resilience is essential for predicting how species will respond under climate change. We are making some headway, although more data are needed, especially from taxonomic groups outside of Drosophila, and across diverse geographical regions. Climate change responses are likely to be complex, and such complexity will be difficult to capture in laboratory experiments. Moving towards well designed field experiments would allow us to not only capture this complexity, but also study more diverse species. 相似文献
385.
Pathy Kibungu Kembelo Dr. Emmy Tuenter Dr. Wouter Vanhove Prof. Dr. Honoré Belesi Katula Prof. Dr. Patrick Van Damme Prof. Dr. Luc Pieters 《化学与生物多样性》2023,20(9):e202300826
Kalaharia uncinata (Schinz) Moldenke, is a tropical erect bushy shrub or subshrub of the Lamiaceae family. It is an endemic plant species of Southern Africa, widely used in the pharmacopoeia against upper respiratory tract infections. A previously conducted ethnobotanical survey revealed that it is believed to contain bioactive substances. However, no relevant phytochemical information was available. This study aimed to perform a phytochemical characterization of K. uncinata and also to discuss the potential bioactivity of the identified phytochemical constituents based on documented data. Ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) was used for profiling and identification of the main phytochemical constituents from leaf extracts (MeOH 90 %, DCM, AcOEt, BuOH, hexane and residue) of K.uncinata. Twenty-four constituents, representing mainly flavonoids (14), followed by phenylethanoid glycosides (7), phenolic acids (2), and an iridoid glycoside (1) were tentatively identified. Most of the identified compounds are documented to have antiviral and anti-inflammatory properties, which could possibly be the rationale behind the use of K. uncinata against upper respiratory tract infections. 相似文献
386.
ObjectiveWe aimed to assess treatment outcomes and disease control status in patients with acromegaly using patient- and clinician-reported outcome tools and to analyze correlations among different components of both tools.MethodsThis cross-sectional study included 72 patients from a national referral center with a median follow-up of 8 (5-12) years. The baseline SAGIT score at diagnosis was determined retrospectively, whereas the follow-up SAGIT and acromegaly quality of life questionnaire (AcroQoL) results were assessed at the most recent visit and by additional telephone interviews.ResultsAll SAGIT subscores decreased significantly from baseline to follow-up (global score from 14 to 4 [P < .001]). The SAGIT scores at baseline did not discriminate the current disease control status. However, a higher baseline SAGIT score and subscore T were associated with uncontrolled disease after the first-line treatment. Diagnostic delay was correlated with baseline S, A, G, and global SAGIT scores. At the follow-up, the global SAGIT score discriminated between cured/controlled and uncontrolled groups (4 vs 6 [P = .007]). The AcroQoL score was 69.3, with the personal relations subscale being the least affected and the physical scale being the most affected. There was no difference in the AcroQoL score between patients classified as uncontrolled or cured/controlled. At baseline and follow-up, there were significant negative correlations between S and A subscores and AcroQoL score. A higher body mass index, the presence of swelling, joint symptoms, headaches, sleep apnea, and hypertension significantly impaired quality of life.ConclusionOur results emphasize the complementary nature of the patient- and clinician-reported outcome tools in acromegaly management. We identified modifiable signs, symptoms, and comorbidities as treatment targets that might help clinicians improve quality of life in this population. 相似文献
387.
Sébastien Villotte Dominique Castex Vincent Couallier Olivier Dutour Christopher J. Knüsel Dominique Henry‐Gambier 《American journal of physical anthropology》2010,142(2):224-234
Enthesopathies—that is, “musculo‐skeletal stress markers”—are frequently used to reconstruct past lifestyles and activity patterns. Relatively little attention has been paid in physical anthropology to methodological gaps implicit in this approach: almost all methods previously employed neglect current medical insights into enthesopathies and the distinction between healthy and pathological aspects has been arbitrary. This study presents a new visual method of studying fibrocartilaginous enthesopathies of the upper limb (modified from Villotte: Bull Mém Soc Anthropol Paris n.s. 18 (2006) 65–85), and application of this method to 367 males who died between the 18th and 20th centuries, from four European identified skeletal collections: the Christ Church Spitalfields Collection, the identified skeletal collection of the anthropological museum of the University of Coimbra, and the Sassari and Bologna collections of the museum of Anthropology, University of Bologna. The analysis, using generalized estimating equations to model repeated binary outcome variables, has established a strong link between enthesopathies and physical activity: men with occupations involving heavy manual tasks have significantly (P‐value < 0.001) more lesions of the upper limbs than nonmanual and light manual workers. Probability of the presence of an enthesopathy also increases with age and is higher for the right side compared with the left. Our study failed to distinguish significant differences between the collections when adjusted for the other effects. It appears that enthesopathies can be used to reconstruct past lifestyles of populations if physical anthropologists: 1) pay attention to the choice of entheses in their studies and 2) use appropriate methods. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
388.
Lower thermal tolerance in nocturnal than in diurnal ants: a challenge for nocturnal ectotherms facing global warming
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CARLOS GARCIA‐ROBLEDO HECTOR CHUQUILLANQUI ERIN K. KUPREWICZ FEDERICO ESCOBAR‐SARRIA 《Ecological Entomology》2018,43(2):162-167
1. The thermal adaptation hypothesis proposes that because thermoregulation involves a high metabolic cost, thermal limits of organisms must be locally adapted to temperatures experienced in their environments. There is evidence that tolerance to high temperatures decreases in insects inhabiting colder habitats and microclimates. However, it is not clear if thermal limits of ectotherms with contrasting temporal regimes, such as diurnal and nocturnal insects, are also adapted to temperatures associated with their circadian activities. 2. This study explores differences in heat tolerance among diurnal and nocturnal ant species in four ecosystems in Mexico: tropical montane, tropical rainforest, subtropical dry forests, and high‐elevation semi‐desert. 3. The critical thermal maximum (CTmax), i.e. the temperature at which ants lost motor control, was estimated for diurnal and nocturnal species. CTmax for 19 diurnal and 12 nocturnal ant species distributed among 45 populations was also estimated. 4. Semi‐desert and subtropical dry forest ants displayed higher tolerances to high temperatures than did ants in tropical rainforest. The lowest tolerance to high temperatures was recorded in tropical montane forest ants. In general, among all habitats, the CTmax of nocturnal ants was lower than that of diurnal ants. 5. An increase in nocturnal temperatures, combined with lower tolerance to high temperatures, may represent a substantial challenge for nocturnal ectotherms in a warming world. 相似文献
389.
Opsariichthine (sensu Oceanologi Et Limnologia Sinica, 1982, 13, 293–298) is a cyprinid group consisting of five genera and endemic to East Asia. Previous studies suggested that there may be many possible cryptic species in this group, but this has not been confirmed. In this study, using mitochondrial cyt b sequences on 1,388 samples and 739 haplotypes, we showed very high species diversity within this group. The results showed that phylogenetic relationships of the opsariichthine group were as ([Nipponocypris‐Parazacco‐Candidia] + [Zacco + Opsariichthys]), and there were multiple deep lineages within several species, flagging putative cryptic species. When a 3% genetic distance was used as a threshold for species delimitation, 35 haplogroups were found, nine haplogroups in Candidia‐Parazacco‐Nipponocypris group, six haplogroups in the Zacco group, and 20 haplogroups in the Opsariichthys group. We consider all of them to be putative until determination of distinct species based on the tree topology, geographic distributions, or a combination of both. In addition, two kinds of species delimitation tools, ABGD and PTP, were applied to construct molecular operational taxonomic units (MOTUs). The ABGD method revealed nine MOTUs in Candidia‐Parazacco‐Nipponocypris group, two MOTUs in the Zacco group, and 17 MOTUs in the Opsariichthys group. And the PTP method revealed 10 MOTUs in Candidia‐Parazacco‐Nipponocypris group, 10 MOTUs in the Zacco group, and 29 MOTUs in the Opsariichthys group. Therefore, there should be more species in the opsariichthine group than presently described. Based on the molecular data and morphological characteristics, we proposed Opsariichthys macrolepis as a valid species and described its morphological diagnostic characters. 相似文献
390.
STEFANO CONTI ENRICO SERPAGLI 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1987,20(1):1-20
A membranous, cap-like structure was discovered in the bryozoan genus Hallopora from upper Ordovician siltstones from Sardinia. The structure is interpreted to be analogous to the perimetrical attachment organ and to the part of the membranous sac sustaining the sphincter muscle in Recent cyclostomes. The progressive mineralization of the cap-like apparatus occurred in later ontogenetic stages of the colony in order to have the function of a terminal diaphragm. This diaphragm is related to a particular degeneration—regeneration cycle very similar to the cyclic growth patterns (intracolony overgrowths) of some post-Palaeozoic cyclostomes. After this phase the colony seems to end its life cycle. 相似文献