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601.
Large‐scale ecological surveillance data were analysed to determine the locations of apparent eutrophication effects across common British vegetation types between 1990 and 1998. Plant species composition was recorded from a total of 9514 fixed plots located in a stratified, random sample of 501 1 km squares across Britain. Changes in plant species composition along a gradient of substrate fertility were inferred from statistical tests of change in mean Ellenberg fertility value calculated for each fixed plot. Plots were grouped by eight vegetation types, five landscape features (hedges, road verges, watercourse banks, small biotopes, larger units in fields and unenclosed land) and six environmental zones. Tests of change in mean Ellenberg value were carried out on all combinations of these strata. Decision tree modelling was used to identify groups of test outcomes sharing the same direction of change and where each group was defined by a minimum number of strata. Post hoc power analysis was used to select statistically non‐significant test outcomes that could be used to infer stability in the sampled sub‐population. Out of a total of 142 tests of change in fertility value, 67% were increases, 8% were reductions and 25% indicated stability. The best overall predictor of increases in fertility value, and therefore of shifts in favour of plants suited to higher substrate fertility, was vegetation type. Irrespective of landscape feature and environmental zone, increased means were associated with infertile grasslands, moorland, upland woodlands and heath/bog. Already highly fertile grasslands and woodland assemblages in lowland Britain remained largely stable. The small number of decreasing test outcomes were associated with arable land in Scotland, Wales and western England. These patterns of change are hypothesized to reflect pervasive land‐use drivers combined with the inherent responsiveness of the vegetation.  相似文献   
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In the past decade, there have been regular outbreaks of bluetongue (BT) in many parts of Europe. Owing to the presence of BT disease and its vectors in countries adjacent to Switzerland, an initial entomological survey was conducted in 2003, which established the presence of several midges of the genus Culicoides (Diptera: Ceratopogonidae). Subsequently, a sentinel herd monitoring system was established with the primary entomological aim being the determination and further study of Culicoides population compositions. Insects were collected in 2005 and 2006 at seven sentinel herd sites in the south of Switzerland (canton of Ticino) near the border of Italy, using Onderstepoort-type light traps. This region is botanically and zoologically similar to the Mediterranean and is one of the warmest and most humid areas of the country, hence it is considered a potential access path for BT disease into Switzerland. Collections were made at four cattle farms, two equestrian centres and one goat farm. Sites were sampled four times per month from June to October. Traps were operated from dusk until dawn and samples were collected monthly for analysis through microscopy as well as a Culicoides imicola -specific PCR. Results confirmed the absence of C. imicola (Kieffer) and demonstrated that the potential BT virus vectors are highly abundant, notably: Culicoides obsoletus (Meigen), Culicoides scoticus (Downes & Kettle) and Culicoides dewulfi (Goetghebuer) subgenus Avaritia and Culicoides pulicaris (Linnaeus) subgenus Culicoides . These findings expand the current knowledge of Culicoides population composition in the southern part of the Switzerland. Culicoides cataneii (Clastrier), Culicoides flavipulicaris (Dzhafarov), Culicoides indistinctus (Khalaf), Culicoides nubeculosus (Meigen) and species of the Grisescens complex were reported for the first time in Switzerland.  相似文献   
604.
An expatriate to Ivory Coast (supposedly allergic to artemether-lumefantrine) was diagnosed with severe malaria in Spain. Parasitemia increased from 2% up to 21% within 24?h under quinine (10?mg/kg) and clindamycin (450?mg/8?h) combination treatment. Molecular profiling of the patient revealed the presence of molecular markers of quinine and other antimalarials resistance. Additionally, multiple copies of pfpm2 gene were also noticed in the patient sample, despite the absence of piperaquine drug pressure in Ivory Coast. Parasitemia was cleared with artesunate (2.4?mg/kg) under a desensitization protocol. Nevertheless, detection of early treatment failure is needed mainly in cases of suspected antimalarial resistance.  相似文献   
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1. Field populations of the teak defoliator larvae, Hyblaea puera Cramer exhibit colour polyphenism under different population densities: greyish‐green with black‐ and orange‐coloured dorsal bands in low‐density endemic populations and uniformly black or intermediate colour during high‐density population. 2. The density dependence of colour polyphenism was confirmed by field monitoring of H. puera populations during 2008–2010. 3. The above findings were later substantiated by rearing H. puera larvae under different densities (i.e. solitary and crowded in the laboratory). Ninety one per cent of the solitary reared laboratory population developed bright coloration whereas, 92% of the group reared larvae turned to black. Eight per cent of larvae from both the rearing densities were of intermediate colour. 4. Density‐dependent resistance build‐up against H. puera nucleopolyhedrovirus by H. puera were tested using the fifth instar larvae. The results showed three‐fold increase of median lethal dose (LD50) value for the group reared larvae (5332 polyhedral occlusion bodies/larvae) compared to the solitary reared ones (1727 polyhedral occlusion bodies/larva) and also significant difference for the mean time to death (3.6 and 3.3 days, respectively). 5. The study revealed the strong influence of larval density on H. puera larval melanism and resistance build‐up against H. puera nucleopolyhedrovirus.  相似文献   
607.
ObjectiveActive surveillance (AS) has been shown to be a safe approach that can effectively block transition from overdiagnosis to overtreatment in patients with low-risk papillary thyroid microcarcinoma (PTMC). This study aimed to determine whether the AS approach can be implemented in China and investigate the population characteristics of Chinese patients who underwent AS.MethodsThe epidemiologic and clinical characteristics as well as patient adherence were evaluated in 115 patients who underwent AS management as an alternative to immediate surgery for low-risk (or highly suspected) PTMC.ResultsThe mean patient age was 41.8 ± 10.3 years, with 41.7% and 4.4% of the patients aged <40 and ≥60 years, respectively. The median baseline diameter of index tumors was 4 (range, 3-6) mm, with 73.0% of the tumors being ≤5 mm. A total of 84.4% of the patients had a junior college, college, or graduate degree, and 83.5% were employed by the government, public institutions, companies, or technical posts. After a median 25-month follow-up, a tumor growth of ≥3 mm occurred in 3 patients (2.6%), and no new lymph node metastasis occurred. Surgery was performed in 4 patients because of patient preferences rather than because of disease progression. There was satisfactory adherence in 109 patients (94.8%) in a simulated ideal medical environment.ConclusionThe AS approach can be used as an alternative to low-risk PTMC management in China. Given the difference in epidemiologic and clinical characteristics, Chinese institutions should fully consider the features of the Chinese population while developing candidate criteria, surveillance intervals, and follow-up strategies for AS.  相似文献   
608.
Abstract. A survey of the dengue vector mosquito Aedes aegypti was undertaken using runnel traps to detect immature stages (larvae and pupae) in flooded disused mine shafts and wells in Charters Towers, Queensland, Northern Australia. The town has a history of dengue fever since 1885 when goldminers were the first recorded victims. During the latest dengue epidemic in 1993, 2% of the population had laboratory-confirmed dengue virus Type 2, despite source reduction of Ae.aegypti breeding-sites at ground level or above. This led to suspicions that dengue vector Ae.aegypti breeding-sites might be below ground level. When surveyed in March 1994, Ae.aegypti immatures were found in 9/10 wells and 1/6 mine shafts. The water in wells and mines had similar characteristics -except that turbidity was higher in the mines, which more often contained predators of mosquito immatures.
The copepod Mesocyclops aspericornis was collected from water in 1/10 wells and 2/6 mine shafts. Laboratory predation trials resulted in 95.5–100% predation by 25 copepods/1 on Ae.aegypti first-instar larvae up to 200 larvae/1. Five wells containing Ae.aegypti in the survey were inoculated with fifty indigenous M.aspericornis , and five wells (one positive and four negative in the survey) were left untreated as controls. Nine months later, in December 1994, Ae.aegypti had been eliminated from all five treated wells but all untreated control wells contained Ae.aegypti , except for one well that contained a natural population of M.aspericornis. The role of wells and mines as winter/ dry season refuges of Ae.aegypti in northern Australia is reviewed, and we recommend the use of M.aspericornis as a cost-effective, environmentally acceptable and persistent agent for the sustainable control of Ae.aegypti , especially in inaccessible breeding sites.  相似文献   
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《Endocrine practice》2021,27(5):383-389
ObjectiveTo understand patient perspective regarding recommended changes in the 2015 American Thyroid Association (ATA) guidelines. Specifically, in regard to active surveillance (AS) of some small differentiated thyroid cancer (DTC), performance of less extensive surgery for low-risk DTC, and more selective administration of radioactive iodine (RAI).MethodsAn online survey was disseminated to thyroid cancer patient advocacy organizations and members of the ATA to distribute to the patients. Data were collected on demographic and treatment information, and patient experience with DTC. Patients were asked “what if” scenarios on core topics, including AS, extent of surgery, and indications for RAI.ResultsSurvey responses were analyzed from 1546 patients with DTC: 1478 (96%) had a total thyroidectomy, and 1167 (76%) underwent RAI. If there was no change in the overall cancer outcome, 606 (39%) of respondents would have considered lobectomy over total thyroidectomy, 536 (35%) would have opted for AS, and 638 (41%) would have chosen to forego RAI. Moreover, (774/1217) 64% of respondents wanted more time with their clinicians when making decisions about the extent of surgery. A total of 621/1167 of patients experienced significant side effects with RAI, and 351/1167 of patients felt that the risks of treatment were not well explained. 1237/1546 (80%) of patients felt that AS would not be overly burdensome, and quality of life was the main reason cited for choosing AS.ConclusionPatient perspective regarding choice in the management of low-risk DTC varies widely, and a large proportion of DTC patients would change aspects of their care if oncologic outcomes were equivalent.  相似文献   
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