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31.
Increased microbial burden within the wound often complicates wound healing and may lead to subsequent infection or delayed healing. Here, we investigate a novel topical for addressing wound contamination that utilizes hyperosmotic saccharides with a cell membrane disrupting emulsion. These hyperosmotic nanoemulsions (HNE) were administered topically in a full‐thickness biopsy model of wound healing. Results show that HNE were well tolerated in noninfected animals with no indications of dermal irritation or acute toxicity. Additionally, HNE was able to reduce bacterial bioburden (Escherichia coli and Enterococcus faecalis) levels by 3 logs within 24 h when wounds were inoculated with 5 × 106 total CFU. These bactericidal values were similar to wounds treated with silver sulfadiazine. Wound closure showed HNE wounds closed in 7.6 ± 0.2 days while SSD and control required 10.2 ± 0.4 and 10.4 ± 0.3 days, respectively. HNE maintained a moist wound environment, were well debrided, and exhibited improved hemostatic response. Further histological examination revealed enhanced granulation tissue as compared to silver sulfadiazine and control cohorts. These results were corroborated with 3D topographical imprints of the wounds at day 14 which qualitatively showed a smoother surface. In contrast, silver sulfadiazine appeared to delay wound closure. Finally, dermal sensitization and irritation studies conducted in guinea pig and rabbits did not reveal any acute dermal side effects from HNE exposure. The cumulative data indicates nonantibiotic‐based HNEs may be a promising topical treatment for the management of contaminated wounds.  相似文献   
32.

Background

Construction-related ocular injuries are an important cause of vision loss but few studies on the incidence, epidemiology and nature of these injuries exist.

Aims

Due to the perceived increase in occupation-related eye injuries in non-nationals we aimed to investigate the nature of such injuries presenting to a single eye unit over a two-month period.

Methods

One hundred and fifty-five patients presenting to the accident and emergency department with construction related ocular injury were examined.

Results

Of 155 patients, 80 were Irish and 75 non-national, of whom 60, 21.3 and 6.7% were Polish, Lithuanian and Romanian, respectively. Common causative factors included hammering, grinding, drilling and splash injury. Average rate of eyewear protection usage was 35%, with attendance at safety courses highest in Irish nationals. A penetrating eye injury rate of 4.9% overall was observed, all in non-nationals.

Conclusion

Construction related ocular injury is a serious cause of visual loss in non-nationals. Greater adherence to safety regulations and training is required.
  相似文献   
33.
OBJECTIVE: The distribution of diabetic retinopathy in black populations is largely unknown. The authors present retinopathy data from the predominately black participants of the Barbados Eye Study (BES). DESIGN AND PARTICIPANTS: Prevalence study of 4631 participants based on a random sample of the Barbados population 40 to 84 years of age (84% participation). MAIN OUTCOME MEASURES: Diabetes was defined as self-reported history of physician-diagnosed diabetes or glycosylated hemoglobin greater than 10% (>2 standard deviations above the population mean of persons without a diabetes history). Retinopathy was assessed by independent gradings of 30 degrees color stereo fundus photographs of the disc and macula. RESULTS: Diabetes was present in 19.4% of black (n = 4314), 15.2% of mixed (black and white; n = 184), and 7.5% of white/other (n = 133) self-reported racial groups. In the black/mixed population, regardless of diabetes status, the prevalence of retinopathy was 5.9%. In the 636 black and mixed participants with diabetes, the prevalence of retinopathy was 28.5%: 19.8% had minimum changes, 7.7% had moderate changes, and 0.9% had severe retinopathy. Clinically significant macular edema (CSME) was found in 8.6% of those with diabetes. CONCLUSIONS: In the population of African origin, approximately 1 in 17 persons had retinopathy. Among those with diabetes, 28.5% had retinopathy and 8.6% had CSME. These results highlight the clinical and public health relevance of diabetic retinopathy in the black population.  相似文献   
34.
Abstract – Aims: This study sought to establish the prevalence of traumatic dental injuries in the primary dentition of Irish children and to investigate the relationship between dental trauma and non‐nutritive sucking habits. Materials and methods: Following ethical approval, a variety of schools and crèches in an urban setting were identified and parents of over 1000 children were contacted. Consent was obtained, and parental questionnaires were completed prior to a clinical examination of the children by one operator in a non‐dental setting. Signs of previous dental trauma were noted, and overbite and overjet were measured. Results: Eight hundred and thirty‐nine children were examined. The prevalence of dental trauma was 25.6%, with boys more frequently affected. The most commonly observed dental injury was fracture of enamel (39.4%), followed by crown discolouration (20.2%). Only 38.8% of the children with a reported history of trauma sought dental care. Non‐nutritive sucking habits were reported in 63.5% of the sample, and these habits, if prolonged, were significantly associated with anterior open bites and increased overjet (P < 0.001). Using regression analysis, it was established that the risk of dental injury is 2.99 times greater if the child has an overjet >6 mm and 2.02 times greater if the child has an anterior open bite. Conclusions: Non‐nutritive sucking habits are associated with the establishment of anterior open bite and increased overjet in the primary dentition. These malocclusions are, in turn, significantly associated with an increased prevalence of dental trauma in the primary dentition.  相似文献   
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The development and use of drug eluting stents has brought about significant improvements in reducing in-stent restenosis, however, their long term presence in the artery is still under examination due to restenosis reoccurring. Current studies focus mainly on stent design, coatings and deployment techniques but few studies address the issue of the physics of three dimensional mass transport in the artery wall. There is a dearth of adequate validated numerical mass transport models that simulate the physics of diffusion dominated drug transport in the artery wall whilst under compression. A novel experimental setup used in a previous study was adapted and an expansion of that research was carried out to validate the physics of three dimensional diffusive mass transport into a compressed porous media. This study developed a more sensitive method for measuring the concentration of the species of interest. It revalidated mass transport in the radial direction and presented results which highlight the need for an evaluation of the governing equation for transient diffusive mass transport in a porous media, in its current form, to be carried out.  相似文献   
37.
Milroy disease (MD) is an autosomal dominantly inherited primary lymphedema. In 1998, the gene locus for MD was mapped to 5q35.3 and variants in the VEGFR3 (FLT4) gene, encoding vascular endothelial growth factor receptor 3 (VEGFR3), were identified as being responsible for the majority of MD cases. Several reports have since been published detailing pathogenic FLT4 mutations. To date, a total of 58 different variants in FLT4, 20 of which are unpublished, have been observed in 95 families with MD. A review of published mutations is presented in this update. Furthermore, the unpublished variants are presented including clinical data. Comparison of clinical features in patients and their families with the same mutations reveals incomplete penetrance and variable expression, making genotype–phenotype correlations difficult. Most mutations are missense, but a few deletions and one splicing variant have also been reported. Several animal models have confirmed the role of VEGFR3 in lymphangiogenesis and studies show mutant VEGFR3 receptors are not phosphorylated. Here, an MD patient with the same p.Ile1053Phe change as seen in the Chy mouse is presented for the first time. This finding confirms that this mouse lineage is an excellent model for MD. All the data reviewed here has been submitted to a database based on the Leiden Open (source) Variation Database (LOVD) and is accessible online at www.lovd.nl/flt4.  相似文献   
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A variety of ecological processes influence diversity and species composition in natural communities. Most of these processes, whether abiotic or biotic, differentially filter individuals from birth to death, thereby altering species’ relative abundances. Nonrandom outcomes could accrue throughout ontogeny, or the processes that generate them could be particularly influential at certain stages. One long-standing paradigm in tropical forest ecology holds that patterns of relative abundance among mature trees are largely set by processes operating at the earliest life cycle stages. Several studies confirm filtering processes at some stages, but the longevity of large trees makes a rigorous comparison across size classes impossible without long-term demographic data. Here, we use one of the world’s longest-running, plot-based forest dynamics projects to compare nonrandom outcomes across stage classes. We considered a cohort of 7,977 individuals in 186 species that were alive in 1971 and monitored in 13 mortality censuses over 42 y to 2013. Nonrandom mortality with respect to species identity occurred more often in the smaller rather than the larger size classes. Furthermore, observed nonrandom mortality in the smaller size classes had a diversifying influence; species richness of the survivors was up to 30% greater than expected in the two smallest size classes, but not greater than expected in the larger size classes. These results highlight the importance of early life cycle stages in tropical forest community dynamics. More generally, they add to an accumulating body of evidence for the importance of early-stage nonrandom outcomes to community structure in marine and terrestrial environments.Processes that operate nonrandomly with respect to species identity contribute to the structure of natural communities (13). Evidence from diverse rain forests includes demographic transitions from seeds to seedlings (4, 5), at the seedling (6, 7) and sapling stages (8) and among large trees (912). Although the relative contributions of nonrandom processes at each life cycle stage to determining patterns of abundance and diversity in the mature canopy are unknown, one long-standing paradigm is that community assembly is mediated primarily by events occurring from seed dispersal through seedling germination and small-sapling establishment (1317). However, despite suggestive patterns (6, 7, 18, 19), evidence is lacking for the comparative strength of early-stage dynamics in determining canopy abundance and diversity.Numerous studies demonstrate significant interspecific variation in the susceptibility of tropical tree seedlings to postgermination hazards, including natural enemies (20, 21), adverse climatic or edaphic conditions (22), physical damage (23), and the crowding or shared-enemies effects of con- and heterospecific neighbors (24, 25). In other words, the per capita probability of seedling mortality is nonrandom because the probability of death is not the same for all individuals in a local community – it is dependent to some degree on species identity. In plant communities in which generation times are relatively short, experiments have demonstrated that nonrandom mortality through these early transitions can be sufficiently strong to affect the species composition of mature plants (2629). Such demonstrations are impossible in studies of a few decades or less in duration when generation times are long and even juveniles live for several decades or centuries, such as in many tropical forests. Even so, some hypotheses explicitly identify stressors that affect plants at the earliest life cycle stages (such as pests and pathogens, 13, 14, 30) as disproportionately influential. In addition, some empirical studies find a lack of support for nonrandom processes operating among larger stems (31, 32). Together these hypotheses and observations provide the rationale underpinning the considerable body of research on seed and seedling dynamics in tropical forests worldwide. However, no empirical or experimental assessment has been made of the relative contributions across life cycle stages from nonrandom mortality.Here, we evaluate the comparative contribution of early-stage dynamics using a multidecadal study of a tropical forest dynamics plot initiated by one of us (J.H.C.) in 1963 at a site in north Queensland, Australia. We considered a cohort of 7,977 individuals in 186 species that were alive on the plot in 1971, from tiny seedlings to large canopy trees, whose fates were monitored in 13 mortality censuses over 42 y to 2013. Individuals were assigned to one of six size classes (
Size class*N in 1971S in 1971S in 2013D in 2013 (% mortality)
SC1 (0-6.0-cm ht)1,46591241,421 (97.0)
SC2 (6.1–15.2-cm ht)1,275105471,156 (90.7)
SC3 (15.3–36.6-cm ht)1,29110677965 (74.7)
SC4 (36.7–182.9-cm ht)1,351124101639 (47.3)
SC5 (183.0-cm ht – 10-cm dbh)1,208135123330 (27.3)
SC6 (≥10.1-cm dbh)1,387122113357 (25.7)
Open in a separate windowS, number of species; N, number of stems alive in 1971; D, number of stems that died by 2013; dbh, diameter at breast height.*The original units of measurement on this plot were decimal inches and feet. Individuals < 3.2-inches girth have always been measured for height, to the nearest 0.1 ft. The upper height limits of size classes 1–4 are the metric equivalents of 0.2, 0.5, 1.2, and 6.0 ft.Our analyses proceeded in three stages. First, we determined the percentage, P, of species in each size class dying nonrandomly between 1971 and 13 progressively longer census periods to 2013. A species died nonrandomly within a given size class if the observed number of individuals dying over a census period was significantly different from the number of deaths expected under Monte Carlo simulations (10,000 runs) in which the probability of mortality was random with respect to species identity within the size class (i.e., “expected mortality”). Second, we determined for each census period and size class the effect of nonrandom mortality on the observed species richness of both the stems that survived (SS) and the stems that died (SD). From the simulations we generated means and 95% confidence limits for the expected numbers of survivors for each species in each size class in each census interval. We also calculated means and 95% confidence limits for the expected numbers of deaths for each species in each size class and census interval, as well as the means and 95% confidence limits for expected SS and SD. Third, we investigated frequency-dependent mortality as a potential mechanism explaining departures from expected species richness among observed survivors and the stems that died.  相似文献   
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