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1.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
2.
Sukal Sean A. MD PhD † Tudisco Marie HT † Strippoli Barbara HT † Nehal Kishwer S. MD † 《Dermatologic surgery》2005,31(7):763-766
Background Processing multiple tissue sections in large Mohs cases is time consuming and labor intensive.
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency. 相似文献
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency. 相似文献
3.
G Wilms G Marchal E Kersschot P Vanhoenacker P Demaerel H Bosmans H Carton A L Baert 《Journal of computer assisted tomography》1991,15(3):359-364
Axial and sagittal proton density and T2-weighted MR images (TR 2,500-3,000 ms, TE 15-22 and 85-90 ms) were performed in 50 patients with multiple sclerosis (MS) on a 1.5 T superconductive system. The number of plaques on the axial and sagittal images in the periventricular white matter, the corpus callosum, the brain stem, the cerebellum, and the basal ganglia were counted separately by two independent observers. A total of 858 lesions (mean 17.40 +/- 21.57) were seen on the axial series and 1,196 (mean 24.32 +/- 26.22) on the sagittal scans. More lesions were visualized on sagittal images in the periventricular region (mean 18.79 +/- 21.69 versus 13.34 +/- 16.45; p less than 0.001) and the corpus callosum (mean 3.00 +/- 2.72 versus 0.57 +/- 1.19; p less than 0.001). In the brain stem more lesions were visualized on the axial images (mean 1.55 +/- 2.55 versus 0.87 +/- 1.20; p less than 0.05). In the cerebellum and basal ganglia, scans in the two planes were equivalent (p greater than 0.5). In three patients lesions were seen on the sagittal series, while the axial scans were normal. Sagittal T2-weighted images appear to demonstrate significantly more MS plaques than transverse images, especially in the periventricular region and the corpus callosum. This is explained by partial volume averaging, by the orientation of some cerebral structures (e.g., corpus callosum) with regard to the section plane, and by the longer diameter of the lesions in the axial plane. 相似文献
4.
BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome. 相似文献
5.
W. D. Boeckx V. V. Vijay Haribhakti L. Bosmans J. A. Gruwez 《European journal of plastic surgery》1992,15(3):127-132
Summary In 50 rats, different types of end-to-side carotid artery anastomoses were compared. In one technique, a longitudinal split in the long axis of the vessel was performed to enhance the diameter of the anastomosis. This theoretical advantage was not confirmed in this series. The clamping time, anastomoses time, and tamponade time were increased significantly when compared with a simple, slightly oblique end-to-side anastomosis. This study highlighted that the most simple type of end-to-side anastomosis gave less bleeding, achieved a quicker water-tight anastomosis and decreased the risk of late problems. 相似文献
6.
7.
Ghrelin expression in hyperplastic and neoplastic proliferations of the enterochromaffin-like (ECL) cells 总被引:1,自引:0,他引:1
Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation
of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal
and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus
far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL)
cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as
well.
Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three
with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using
a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin,
gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation
with the ghrelin staining results.
All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains
for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia,
as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such
staining was confined to the Sevier-Munger, and VMAT-2 positive cells only.
Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability
to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the
orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL
cell proliferations needs to be investigated further. 相似文献
8.
9.
Cloning and developmental expression analysis of the murine homolog of the spinocerebellar ataxia type 1 gene (Sca1) 总被引:2,自引:0,他引:2
Banfi S; Servadio A; Chung M; Capozzoli F; Duvick LA; Elde R; Zoghbi HY; Orr HT 《Human molecular genetics》1996,5(1):33-40
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant
neurodegenerative disorder caused by the expansion of a CAG trinucleotide
repeat which encodes glutamine in the novel protein ataxin-1. In order to
characterize the developmental expression pattern of SCA1 and to identify
putative functional domains in ataxin-1, the murine homolog (Sca1) was
isolated. Cloning and characterization of the murine Sca1 gene revealed
that the gene organization is similar to that of the human gene. The murine
and human ataxin-1 are highly homologous but the CAG repeat is virtually
absent in the mouse sequence suggesting that the polyglutamine stretch is
not essential for the normal function of ataxin-1 in mice. Cellular and
developmental expression of the murine homolog was examined using RNA in
situ hybridization. During cerebellar development, there is a transient
burst of Sca1 expression at postnatal day 14 when the murine cerebellar
cortex becomes physiologically functional. There is also marked expression
of Sca1 in mesenchymal cells of the intervertebral discs during development
of the spinal column. These results suggest that the normal Sca1 gene, has
a role at specific stages of both cerebellar and vertebral column
development.
相似文献
10.
Carton AK Vandenbroucke D Struye L Maidment AD Kao YH Albert M Bosmans H Marchal G 《Medical physics》2005,32(6):1684-1695
The modulation transfer function (MTF) describes the spatial resolution properties of imaging systems. In this work, the accuracy of our implementation of the edge method for calculating the presampled MTF was examined. Synthetic edge images with known MTF were used as gold standards for determining the robustness of the edge method. These images simulated realistic data from clinical digital mammography systems, and contained intrinsic system factors that could affect the MTF accuracy, such as noise, scatter, and flat-field nonuniformities. Our algorithm is not influenced by detector dose variations for MTF accuracy up to 1/2 the sampling frequency. We investigated several methods for noise reduction, including truncating the supersampled line spread function (LSF), windowing the LSF, applying a local exponential fit to the LSF, and applying a monotonic constraint to the supersampled edge spread function. Only the monotonic constraint did not introduce a systematic error; the other methods could result in MTF underestimation. Overall, our edge method consistently computed MTFs which were in good agreement with the true MTF. The edge method was then applied to images from a commercial storage-phosphor based digital mammography system. The calculated MTF was affected by the size (sides of 2.5, 5, or 10 cm) and the composition (lead or tungsten) of the edge device. However, the effects on the MTF were observed only with regard to the low frequency drop (LFD). Scatter nonuniformity was dependent on edge size, and could lead to slight underestimation of LFD. Nevertheless, this negative effect could be minimized by using an edge of 5 cm or larger. An edge composed of lead is susceptible to L-fluorescence, which causes overestimation of the LFD. The results of this work are intended to underline the need for clear guidelines if the MTF is to be given a more crucial role in acceptance tests and routine assessment of digital mammography systems: the MTF algorithm and edge object test tool need to be publicly validated. 相似文献