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71.

Purpose

The purpose of this study was to investigate how the use of multi-modal rigid image registration integrated within a standard picture archiving and communication system affects the efficiency of a radiologist while performing routine interpretations of cases including prior examinations.

Methods

Six radiologists were recruited to read a set of cases (either 16 neuroradiology or 14 musculoskeletal cases) during two crossover reading sessions. Each radiologist read each case twice, one time with synchronized navigation, which enables spatial synchronization across examinations from different study dates, and one time without. Efficiency was evaluated based upon time to read a case and amount of scrolling while browsing a case using Wilcoxon signed rank test.

Results

Significant improvements in efficiency were found considering either all radiologists simultaneously, the two sections separately and the majority of individual radiologists for time to read and for amount of scrolling. The relative improvement for each individual radiologist ranged from 4 to 32% for time to read and from 14 to 38% for amount of scrolling.

Conclusion

Image registration providing synchronized navigation across examinations from different study dates provides a tool that enables radiologists to work more efficiently while reading cases with one or more prior examinations.
  相似文献   
72.
The present study aims to assess the effect of three forms of carbon, i.e., charcoal, biochar and activated carbon using as soil amendments (or soil conditioners) in two soils, an acid and alkaline one. For this purpose, a pot experiment was conducted by mixing six sub-samples for each soil along with the three amendments in the appropriate proportion. Total, pseudo-total and available metal concentrations were determined. Moreover, the BCR fractionation method was applied and the four soil fractions were identified. A significant decrease in the concentrations of all four metals in the water-soluble and exchangeable fraction (F1) was observed. At the same time, a high reduction was observed in the available concentrations of metals as well, ie those that were extracted after using the DTPA solution. Soil indices were also used in order to monitor and evaluate the possible ecological risk and the effect in metal concentrations after the application of the amendments. The use of the studied materials can be very promising soil conditioners, as they can precisely, economically, time-effectively, and efficiently can remediate soils, moderately contaminated with toxic metals.  相似文献   
73.
74.
It has been proposed that apolipoprotein J (apo J) and paraoxonase-1 (PON1) correlate with the extent and severity of ischemic heart disease (IHD). This article compares apo J and PON1 serum concentrations, PON1 activity, and the apo J/PON1 ratio in 138 IHD patients (64 statins users and 74 statin nonusers) referred for angiography and possible percutaneous coronary intervention. The effect of statin treatment on apo J and PON1 concentrations, PON1 activity, and the degree of coronary artery stenosis were evaluated. In both groups, apo J levels were increased, whereas PON1 concentration and activity decreased. IHD patients on statins had significantly lower apo J concentration and higher PON1 concentration and activity. Patients on statins had less coronary artery stenosis. High apo J levels, low PON1 levels, low PON1 activity, and a high apo J/PON1 ratio were associated with IHD. Statin treatment reverses these changes, probably by multiple beneficial actions.  相似文献   
75.
bcl-2/IgH fusion is considered a genetic error which occurs at the diversity (D) to joining (JH) stage of the gene rearrangement process in the immunoglobulin heavy chain (IgH) gene locus. Translocations of the bcl-2 protooncogene to the IgH locus at ontogenetically later IgH gene rearrangements are thought to represent exceptions. In the present study we analysed the junctional nucleotide sequence of 18 bcl-2/IgH fusion genes identifiable by polymerase chain reaction performed on DNA extracted from diagnostic lymph node tissue of 14 follicular lymphoma patients. In all clones studied, segments of variable length were found interposed between bcl-2 and JH gene sequences. Nucleotide sequence data analysis and comparisons performed with the corresponding germline sequences using the GenBank/EMBL database revealed the presence of D segments in most of the bcl-2/IgH fusion genes under study (13/18). By the same kind of computer-aided analysis, previously unrecognized D segments were identified in many published junctional sequences. These results suggest that bcl-2/IgH fusion events are very prevalent in rather more differentiated stages in B-cell ontogeny than previously recognized.  相似文献   
76.
The results of several cross-sectional trials suggest that patients with rheumatoid arthritis (RA) have increased vascular risk and cardiovascular mortality. It was demonstrated that inflammation plays a pivotal role in the pathogenesis of both RA and atherosclerosis. This association may explain the high incidence of cardiovascular disease in RA patients. A number of recent studies show that routine statin use in patients with RA offers considerable advantages. Statin treatment has been supported to exert a beneficial effect on disease activity, swollen joint count, endothelial dysfunction, and arterial stiffness in RA patients. These improvements are coupled with a mild to moderate improvement in plasma markers of inflammation, such as C-reactive protein and erythrocyte sedimentation rate. Statins have a satisfactory safety profile with relatively few adverse effects. In the absence of side effects and contraindications, it may be reasonable to consider statin use in selected cases, particularly in patients with a long history of active RA who are at increased cardiovascular risk.  相似文献   
77.
This paper details a novel method to improve wear resistance of dental glass ionomer cement (GIC) restorations. The purpose of this in vitro study was to evaluate the effect of a calcium chloride (CaCl2) solution treatment on surface hardness, surface roughness, compressive strength, water sorption and solubility of three conventional glass ionomer cements (GICs). Additionally, the changes of the Ca composition and morphology of the surface of the tested GICs were also investigated. The experimental groups of the study were: Group 1 (control) specimens after mixing were left in the mold to set without any treatment for 5 min; Group 2 specimens were left in the mold to set for 5 min and then each specimen was immersed in 10 ml of 42.7 wt% CaCl2 solution for 60 s. Statistical analysis was performed using one-way ANOVA and Tukey post hoc tests (a = 0.05). Calcium chloride solution treatment increased surface hardness of the GICs compared to control groups (P < 0.05), while surface roughness and compressive strength did not change after the treatment (P > 0.05). Reduction in water sorption and solubility was detected but not in all CaCl2 solution-treatment groups. No alterations were observed in surface morphology of the GICs, while surface calcium composition was increased after the treatment (P < 0.05). The use of a CaCl2 solution immediately after initial setting of GICs may be advantageous for some properties of the materials and possibly leads to improved prognosis and wear resistance of their restorations.  相似文献   
78.
Follicular lymphoma cells carry surface immunoglobulin whose heavy chain variable (VH) regions exhibit considerable divergence from the aminoacid sequence predicted by the germline nucleotide sequence as a result of the somatic hypermutation process. The present study examined the extent of somatic hypermutation in follicular lymphoma κ light chain variable region (Vκ) genes about which the available data is limited. DNA extracted from fresh frozen lymph node tissue of 14 patients with follicular lymphoma at diagnosis was subjected to polymerase chain reaction (PCR) amplification aimed at detecting clonal VH and VL (L; light chain) gene rearrangements. Clonal Vκ gene rearrangements were detected in 10/14 cases. Amplified VH and Vκ genes of these 10 cases were directly sequenced by the dideoxy-chain termination method. In all cases, rearranged VH genes demonstrated numerous mutations clustering in the complementarity determining regions (CDRs), in keeping with previous reports. The degree of divergence of the rearranged Vκ genes from the closest homologous germline Vκ genes varied significantly. Furthermore, two patterns of mutations were observed: (i) in six cases (60%), mutations were most often of the replacement (R) type (changing the aminoacid sequence of the encoded polypeptide) in the CDRs and of the silent (S) type (leaving the aminoacid sequence of the encoded polypeptide unchanged) in the framework regions (FWRs) resulting in R:S ratios significantly greater than would have occurred by chance; (ii) in four cases (40%), very few or no mutations were observed and the distribution of mutations as well as the R:S mutation ratios did not differ significantly from what would have occurred by chance alone. These findings imply that, compared to their partner heavy chains, the κ light chains of follicular lymphoma neoplastic B-cells' surface immunoglobulin (sIg): (i) are less affected by somatic hypermutation; (ii) play a less significant role in the antigen selection process.  相似文献   
79.
The activity of single-agent docetaxel in patients with platinum pretreated non-small cell lung cancer (NSCLC) has been established in two recent large randomized phase III trials, either against best supportive care or versus single-agent vinorelbine/ifosfamide. Moreover, single-agent gemcitabine has demonstrated significant activity and clinical benefit in platinum- and paclitaxel-pretreated advanced NSCLC. Combination regimens employing these two agents in various doses and schedules have recently been initiated. The gemcitabine/docetaxel combination with or without G-CSF support as salvage therapy of NSCLC pre-treated with platinum+/-paclitaxel-based regimens has been evaluated in four recently published phase II clinical studies and has been shown to represent a tolerable and active regimen in this setting, yielding a 10-33% response rate, thus, warranting randomized comparisons to single-agent gemcitabine or docetaxel, drugs currently recommended in second-line treatment of advanced NSCLC.  相似文献   
80.
Fifty-one primary total hip arthroplasties were performed using Trabecular Metal Monoblock Acetabular Cup System (Zimmer Inc, Warsaw, IN). In a 2-year prospective study, its behavior was closely monitored by clinical, radiologic, and component migration assessment by Ein-Bild-Röntgen-Analyse method. There were no complications. The mean Harris hip score was improved from 41 to 95. A polar gap at the postoperative radiograph was noted at 25% of the arthroplasties, most of which subsequently filled with bone within 6 months. The mean total absolute migration was 0.67 mm. The implant showed excellent early clinical and radiographic behavior. The 2-year migration rate study, as index of long-term survival and success, showed very good early implant stability and, in all cases except one, superior to the available studies for similar design acetabular cups.  相似文献   
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