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11.
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.  相似文献   
12.
This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process.  相似文献   
13.
Das traumatisch bedingte Kompartmentsyndrom des Unterschenkels   总被引:2,自引:0,他引:2  
Zusammenfassung Um den Stellenwert der Sonographie als Methode der Diagnostik von Sp?tsch?den der Muskulatur nach operativ behandeltem Kompartmentsyndrom zu prüfen, wurden 27 Patienten (sechs Frauen, 21 M?nner) der Abteilung für Unfallchirurgie des Universit?tsklinikums Essen am ventralen Unterschenkel nach durchschnittlich 98 Monaten (43 bis 154 Monate) nach dem Trauma standardisiert untersucht und ein Vergleich mit der gesunden Gegenseite durchgeführt. Bei 15 Patienten war die Dermatofasziotomie wegen eines drohenden und bei zw?lf Patienten wegen eines manifesten Kompartmentsyndroms erfolgt. Im Vergleich zur gesunden Gegenseite konnte eine qualitative Gradeinteilung (0 bis 3) der Ver?nderungen erstellt werden, die das Ausma? der Echogenit?tsvermehrung sowie des Verlustes der muskeltypischen Textur wiedergibt. Grauwerthistogramme konnten die qualitative Einteilung best?tigen. Die Gruppe mit manifestem Kompartmentsyndrom zeigte ausschlie?lich deutliche und massive Ver?nderungen (Grad 2 und 3). Bei drohendem Kompartmentsyndrome fand sich zweimal Grad 2 und 13mal Grad 0 oder 1. Die sonographischen Ver?nderungen sind erkl?rbar durch die bekannten pathomorphologischen Zust?nde nach Kompartmentsyndrom der Muskulatur (Denervierung, Vernarbung). Die Sonographie eignet sich zur Beurteilung der Weichteile nach Kompartmentsyndrom. Die Ergebnisse unterstützen die Forderung nach einer frühzeitigen Fasziotomie bei drohendem Kompartmentsyndrom zur Pr?vention vor Muskel- und Nervensch?digungen.
Traumatic compartment syndrome of the lower limb: Significance of ultrasonography in evaluating long-term damage of muscle after dermatofasciotomy
To determine the significance of sonography in evaluating long-term damage of muscle surgically treated for compartment syndrome 27 patients of the Department for Trauma Surgery, University Clinic Essen, Germany, were examined on their anterior lower limb after an average of 98 (43 to 154) months after trauma. They had had a fasciotomy for imminent (n=15) or manifest (n=12) compartment syndrome. Comparing the healthy side a qualitative grading (0 to 3) of the changes could be introduced reflecting the extent of the increase in echogenicity and the loss of the typical muscle texture. Gray scale histograms confirmed the qualitative grading. Patients with manifest compartment syndrome showed severe changes (grade 2 and 3). In imminent compartment syndrome 2 patients with grade 2 and 13 patients with grade 0 or 1 were found. The sonographical changes can be explained by the known pathomorphological changes after compartment syndrome (denervation, scarification). Sonography is useful in the evaluation of soft tissue after compartment syndrome. The results underline the demands of early fasciotomy in imminent compartment syndrome for prevention of damage of muscle and nerve.
  相似文献   
14.
Structure of four amplified DNA novel joints   总被引:8,自引:0,他引:8  
The structures of four novel joints present in the amplified DNA of a Syrian hamster cell line highly resistant to N-(phosphonacetyl)-l-aspartate were analyzed. Novel joints J1, J2, and J4 were formed by recombination between two regions of wild-type DNA, whereas joint J3 is the end point of an inverted duplication. A fraction of the J3 copies displays a cruciform structure in the purified genomic DNA. The formation of J1 and J2 apparently involved a simple breakage and joining of the two wild-type sequences, whereas extra nucleotides are present at the junction point of J3 and J4. The two regions of the wild-type DNA which have recombined to form J1, J2, and J4 show few sequence similarities, indicating that these joints probably resulted from nonhomologous recombination. AT-rich regions are present in the vicinity of the breakpoint for the four joints and eight of 10 crossover points could be associated with putative topoisomerase I cleavage sites. Our results indicate that different types of novel joints are present in the amplified DNA of this cell line, which was isolated after several steps of selection.  相似文献   
15.
A monoclonal antibody directed against a peptide (PS5) specified by RNA complementary to the mRNA coding for substance P (SP), was used to label SP receptors in the rat spinal cord as demonstrated by light and electron microscopy. An immunocytochemical method (avidin-biotin-peroxidase) was used on vibratome sections from rats perfused with paraformaldehyde. Immunoreactivity was observed principally in the two superficial layers of the dorsal horn, in lamina X and the region of motoneurons. The labeling was absent when the antibody was preincubated with the complementary peptide (PS5) used as immunogen. Competition between the anti-complementary peptide antibody and different ligands was tested by preincubation of tissue sections with the ligand in the presence of peptidase inhibitors before addition of the antibody. A specific agonist (SP) or antagonist (spantide, RP 67580) at 10−6M led to total absence of labeling. These results indicate that under our experimental conditions, the anti-complementary peptide antibody recognizes a SP binding site in the rat spinal cord. Electron microscopic study of the two superficial laminae of the dorsal horn showed that immunolabeling was mainly localized extracellularly at apposing neuronal plasma membranes. It was mostly associated with axodendritic or axosomatic appositions. Occasionally labeling was observed between two axon terminals. In all cases, these appositions were non junctional. Generally, neuronal processes involved in these appositions did not contain large granular vesicles. These observations suggest that SP may act in a diffuse, nonsynaptic manner probably on targets distant from SP release sites.  相似文献   
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18.
Cytosine methylation was studied at the level of the euchromatin/heterochromatin transition genomic region of the Arabidopsis chromosome 5 left arm. It has been shown using a monoclonal antibody against 5-methylcytosines that the density of DNA methylation increases from the euchromatin towards the heterochromatin. YACs mapped along this region were characterized for their repeated sequences content. Some of them, corresponding to euchromatin, euchromatin/heterochromatin border and heterochromatin regions, were used as probes for a Southern blot analysis of methylation. This revealed that the degree of mCmCGG and GATmC methylation increases significantly from the euchromatin towards the heterochromatin. Moreover, an analysis of cytosine methylation levels (% of 5-methylcytosine) of different DNA fragments, inside the same genomic region, was performed using PCR and/or Southern blot approaches. There is a gradual increase of methylation along the genomic region analyzed: CpG methylation in the euchromatic fraction, CpG and CpNpG methylation at the euchromatin/heterochromatin transition and an additional asymmetrical methylation in the repeated-heterochromatic fraction. The most methylated repeated family at CpG, CpNpG and asymmetrical sites is the 5S ribosomal DNA, highly methylated even though it is transcribed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
19.
The RGD1 gene from Saccharomyces cerevisiae, which encodes a GTPase-activating protein for the Rho3 and Rho4 small G proteins, exhibits synthetic lethality with the VRP1 and LAS17 genes. Their products are proline-rich proteins that interact with both actin and myosins to ensure polarized growth. By testing functional links, we found that the VRP1 and LAS17 genes are potent suppressors of the rho3Delta mutation. In particular, they restore the polarization of actin patches in rho3Delta cells. Moreover, the vrp1Delta and las17Delta mutations were found to display a similar pattern of genetic interactions with specific actin-linked genes. These mutations also increase the sensitivity to activated forms of both Rho3p and Rho4p. These data support our working model, in which the VRP1 and LAS17 genes define a cellular complex that works in concert with the RHO3-RHO4 signaling pathway in yeast polarized growth. In addition, other observations lead us to propose that Rvs167p may act as a linking protein between the two cellular elements.  相似文献   
20.
We investigated whether different protocols for the digestion of adult human articular cartilage influence the cell yield and capacity to attach and proliferate in culture dishes. Chondrocyte yields were expressed as a percentage of the total number of cells in the tissue, determined both histologically (using the dissector method) and biochemically (measuring the DNA content of tissue digests). Human cartilage specimens (n = 79) were digested using different protocols based on combinations of collagenase II (CGN), trypsin/EDTA, hyaluronidase, and tosyllysylchloromethane (TLCM). Yields of viable chondrocytes were the highest within a specific range of CGN concentrations and digestion times, but always < 22% of the total available cells. The combination of CGN with trypsin/EDTA or TLCM accelerated the digestion process but did not significantly increase cell yields. The percentage of viable cells that attached to culture dishes ranged 75-85% (< 19% of the total) and was reduced by TLCM. Doubling times of attached cells were comparable in all experimental groups. Our results indicate that chondrocyte yields and capacity to attach and proliferate are not highly sensitive to the specific isolation protocol used. However, typically used cartilage digestion protocols yield only a small fraction of the total available cells, possibly introducing an uncontrolled selection of certain chondrocyte subpopulations.  相似文献   
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