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1.
BACKGROUND: It is a common observation that superficial freezing of normal skin and skin tumors may create a transient superficial whitening effect. In this respect, cryoscopy refers to the direct observation by dermoscopy, with or without digital recording, of the visual alterations of the frozen tissues. AIMS: To define the optimal method of cryoscopy and to describe the cryoscopy patterns of normal skin and selected skin lesions. MATERIALS AND METHODS: The influence of (a) different cryogenic sources [solid carbon dioxide (-78.5 degrees C), liquid nitrogen (N(2), -196 degrees C), and a mixture of dimethyl ether and propane (-57 degrees C)], (b) various application methods (spraying, cotton chill tips, copper plate), and (c) freezing time was assessed with regard to clinical feasability, visualization quality, and persistance time of the whitening effect. Cryoscopy patterns of normal skin, callosities and of histologically proven seborrheic keratoses, verrucous hamartomas, molluscum contagiosum, keratoacanthomas, viral warts, condylomas, actinic keratoses, dermatofibromas, skin tags, basal cell carcinomas, angiomas, and melanocytic naevi were assessed. RESULTS: The cryoscopy images of skin highlighted the skin lines. They appeared similar regardless of the freezing source and the application method. The aspects differed according to the nature of the lesions. The cotton chill tip method provided a longer whitening period compared with the other cold sources, both in normal and lesional skin. Hence, it represented the most convenient way for performing digital recording cryoscopy. On normal skin, cryoapplication was limited to about 1.5 s due to pain, resulting in whitening times ranging from 6 to 9 s, which was too short for easy digital recording. On all studied skin tumors, a 10-s N(2) freezing time was not experienced as painful, and blanching time persisted for 20-34 s, allowing easy digital recording. The whitening time was longer with increasing freezing time on both normal and lesional skin. Every single examined normal skin site and all the skin lesions showed a strong whitening effect, except heavily cornified structures, including some keratoses, callosities, and viral warts. Increased contrast of the skin surface texture was observed in almost every studied lesion. CONCLUSION: The N(2) cotton chill tip technique appeared to be the most convenient technique for cryoscopy and provided longer whitening periods compared with the other freezing sources. Pain prevented its use on normal skin, but a series of exophytic skin lesions was conveniently accessible to cryoscopy. The differences in whitening periods of various epidermal components resulted in increased visual contrast, creating typical cryoscopy images for the different exophytic skin tumors. Cryoscopy represents a novel in vivo skin imaging technique that is rapid, non-invasive, cost-effective, and easily performed. It shows both investigative and diagnostic potentials. It is remarkable that cryoscopy pictures closely resemble those yielded by skin capacitance imaging.  相似文献   
2.
13C NMR analysis of relatively low-molecular-weight polypropylenes prepared using the catalyst system MgCl2/TiCl4/phthalate ester-AlEt3-external Lewis base has revealed the presence of up to around 20% butyl (n-Bu) chain ends, indicative of regioirregular (2,1-) monomer insertion followed by chain transfer with hydrogen. The effect of hydrogen on catalyst activity depends on the nature of the external donor, and the results indicate that at least part of the observed increase in catalyst activity in the presence of hydrogen can be ascribed to the regeneration of active species via chain transfer at dormant (2,1-inserted) sites.  相似文献   
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The advent of massive parallel sequencing is rapidly changing the strategies employed for the genetic diagnosis and research of rare diseases that involve a large number of genes. So far it is not clear whether these approaches perform significantly better than conventional single gene testing as requested by clinicians. The current yield of this traditional diagnostic approach depends on a complex of factors that include gene‐specific phenotype traits, and the relative frequency of the involvement of specific genes. To gauge the impact of the paradigm shift that is occurring in molecular diagnostics, we assessed traditional Sanger‐based sequencing (in 2011) and exome sequencing followed by targeted bioinformatics analysis (in 2012) for five different conditions that are highly heterogeneous, and for which our center provides molecular diagnosis. We find that exome sequencing has a much higher diagnostic yield than Sanger sequencing for deafness, blindness, mitochondrial disease, and movement disorders. For microsatellite‐stable colorectal cancer, this was low under both strategies. Even if all genes that could have been ordered by physicians had been tested, the larger number of genes captured by the exome would still have led to a clearly superior diagnostic yield at a fraction of the cost.  相似文献   
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Oral and Maxillofacial Surgery - To evaluate whether periapical surgery affects oral health-related quality of life (OHRQoL) within the first postoperative week. The primary outcomes in 133...  相似文献   
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Background

Telemonitoring of heart failure (HF) patients is increasingly discussed at conferences and addressed in research. However, little is known about actual use in specific countries.

Objective

We aimed to (1) describe the use of non-invasive HF telemonitoring, (2) clarify expectations of telemonitoring among cardiologists and nurses, and (3) describe barriers to the implementation of telemonitoring in Japan and Sweden.

Methods

This study used a cross-sectional survey of non-invasive HF telemonitoring. A total of 378 Japanese (120 cardiologists, 258 nurses) and 120 Swedish (39 cardiologists, 81 nurses) health care professionals from 165 Japanese and 61 Swedish hospitals/clinics nationwide participated in the study (210 in Japan and 98 in Sweden were approached). Data were collected between November 2013 and May 2014 with a questionnaire that was adapted from a previous Dutch study on telemonitoring.

Results

The mean age of the cardiologists and nurses was 47 years and 41 years, respectively. Experience at the current position caring for HF patients was 19 years among the physicians and 15 years among the nurses. In total, 7 Japanese (4.2%) and none of the Swedish health care institutions used telemonitoring. One fourth (24.0%, 118/498) of the health care professionals were familiar with the technology (in Japan: 21.6%, 82/378; in Sweden: 30.0%, 36/120). The highest expectations of telemonitoring (rated on a scale from 0-10) were reduced hospitalizations (8.3 in Japan and 7.5 in Sweden), increased patient self-care (7.8 and 7.4), and offering high-quality care (7.8 and 7.0). The major goal for introducing telemonitoring was to monitor physical condition and recognize signs of worsening HF in Japan (94.1%, 352/374) and Sweden (88.7%, 102/115). The following reasons were also high in Sweden: to monitor effects of treatment and adjust it remotely (86.9%, 100/115) and to do remote drug titration (79.1%, 91/115). Just under a quarter of Japanese (22.4%, 85/378) and over a third of Swedish (38.1%, 45/118) health care professionals thought that telemonitoring was a good way to follow up stable HF patients. Three domains of barriers were identified by content analysis: organizational barriers “how are we going to do it?” (categories include structure and resource), health care professionals themselves “what do we need to know and do” (reservation), and barriers related to patients “not everybody would benefit” (internal and external shortcomings).

Conclusions

Telemonitoring for HF patients has not been implemented in Japan or Sweden. However, health care professionals have expectations of telemonitoring to reduce patients’ hospitalizations and increase patient self-care. There are still a wide range of barriers to the implementation of HF telemonitoring.  相似文献   
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A longitudinal study was performed to (i) investigate the continuity of shedding of extended-spectrum-beta-lactamase (ESBL)-producing Enterobacteriaceae in dogs without clinical signs, (ii) identify dominant plasmid-mediated ESBL genes, and (iii) quantify ESBL-producing Enterobacteriaceae in feces. Fecal samples from 38 dogs were collected monthly for 6 months. Additional samples were collected from 7 included dogs on a weekly basis for 6 weeks. Numbers of CFU per gram of feces for non-wild-type Enterobacteriaceae were determined by using MacConkey agar supplemented with 1 mg/liter cefotaxime (MCC), and those for total Enterobacteriaceae were determined by using MacConkey agar. Cefotaxime-resistant isolates were screened by PCR and sequence analysis for the presence of blaCTX-M, blaCMY, blaSHV, blaOXA, and blaTEM gene families. Bacterial species were identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) analysis. PCR-negative isolates were tested by a double-disk synergy test for enhanced AmpC expression. A total of 259 samples were screened, and 126 samples were culture positive on MCC, resulting in 352 isolates, 327 of which were Escherichia coli. Nine dogs were continuously positive during this study, and 6 dogs were continuously negative. Monthly or weekly shifts in fecal shedding were observed for 23 dogs. Genotyping showed a large variety of ESBL genes and gene combinations at single and multiple consecutive sampling moments. The ESBL genes blaCTX-M-1, blaCTX-M-14, blaCTX-M-15, blaSHV-12, and blaCMY-2 were most frequently found. The mean number of CFU of non-wild-type Enterobacteriaceae was 6.11 × 108 CFU/g feces. This study showed an abundance of ESBL-producing Enterobacteriaceae in dogs in the Netherlands, mostly in high concentrations. Fecal shedding was shown to be highly dynamic over time, which is important to consider when studying ESBL epidemiology.  相似文献   
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