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941.

Purpose

To externally validate models to predict LN metastsis; Karakiewicz nomogram, clinical nodal staging score (cNSS), and pathologic nodal staging score (pNSS) using a different cohort

Materials and Methods

Clinicopathologic data from 500 patients who underwent radical cystectomy and pelvic lymphadenectomy were analyzed. The overall predictive values of models were compared with the criteria of overall performance, discrimination, calibration, and clinical usefulness.

Results

Presence of pN+ stages was recorded in 117 patients (23.4%). Agreement between clinical and pathologic stage was noted in 174 (34.8%). Based on Nagelkerke’s peudo-R2 and brier score, pNSS demonstrated best overall performance. Area under the receiver operating characteristics curve, showed that pNSS had the best discriminatory ability. In all models, calibration was on average correct (calibration-in-the-large coefficient = zero). On decision curve analysis, pNSS performed better than other models across a wide range of threshold probabilities.

Conclusions

When compared to pNSS, current precystectomy models such as the Karakiewicz nomogram and cNSS cannot predict the probability of LN metastases accurately. The findings suggest that the application of pNSS to Asian patients is feasible.  相似文献   
942.
Autism spectrum disorders (ASD) are characterized by social impairments and restricted/stereotyped behaviors and currently affect an estimated 1 in 68 children aged 8 years old. While there has been substantial recent focus on ASD in research, both the biological pathology and, perhaps consequently, a fully effective treatment have yet to be realized. What has remained throughout is the hypothesis that ASD has neurobiological underpinnings and the observation that both the phenotypic expression and likely the underlying etiology is highly heterogeneous. Given the neurodevelopmental basis of ASD, a biologically based marker (biomarker) could prove useful not only for diagnostic and prognostic purposes, but also for stratification and response indices for pharmaceutical development. In this review, we examine the current state of the field for MEG-related biomarkers in ASD. We describe several potential biomarkers (middle latency delays [M50/M100], mismatch negativity latency, gamma-band oscillatory activity), and investigate their relation to symptomology, core domains of dysfunction (e.g., language impairment), and putative biological underpinnings.  相似文献   
943.
944.
945.

Introduction

Many cases of carbon monoxide poisoning in Taiwan are due to burning charcoal. Nevertheless, few reports have analyzed the mortality rate of these patients who survive to reach a hospital and die despite intensive treatment. Therefore, this study examined the clinical features, physiological markers, and outcomes after carbon monoxide poisoning and the associations between these findings.

Methods

We analyzed the records of 261 patients who were referred for management of carbon monoxide intoxication between 2000 and 2010. Patients were grouped according to status at discharge as alive (survivor, n = 242) or dead (non-survivor, n = 19). Demographic, clinical, laboratory, and mortality data were obtained for analysis.

Results

Approximately half of the cases (49.4%) attempted suicide by burning charcoal. Most of the patients were middle-aged adults (33±19 years), and were referred to our hospital in a relatively short period of time (6±10 hours). Carbon monoxide produced many serious complications after exposure: fever (26.1%), hypothermia (9.6%), respiratory failure (34.1%), shock (8.4%), myocardial infarction (8.0%), gastrointestinal upset (34.9%), hepatitis (18.4%), renal failure (25.3%), coma (18.0%) and rhabdomyolysis (21.8%). Furthermore, the non-survivors suffered greater incidences of hypothermia (P<0.001), respiratory failure (P<0.001), shock (P<0.001), hepatitis ((P=0.016), renal failure (P=0.003), coma (P<0.001) than survivors. All patients were treated with high concentration of oxygen therapy using non-rebreather mask. However, hyperbaric oxygen therapy was only used in 18.8% of the patients. In a multivariate-Cox-regression model, it was revealed that shock status was a significant predictor for mortality after carbon monoxide poisoning (OR 8.696, 95% CI 2.053-37.370, P=0.003). Finally, Kaplan-Meier analysis confirmed that patients with shock suffered greater cumulative mortality than without shock (Log-rank test, Chi-square 147.404, P<0.001).

Conclusion

The mortality rate for medically treated carbon monoxide-poisoned patients at our center was 7.3%. Furthermore, the analysis indicates that shock was most strongly associated with higher risk of mortality.  相似文献   
946.

Background

Sudden sensorineural hearing loss (SSNHL) is a relatively common condition that is usually of unknown etiology. A number of individual studies have investigated the association between various serum lipids and SSNHL; however, the findings have been inconsistent. In an attempt to obtain more definitive information on the relationship between serum lipids and SSNHL, we carried out a systematic review and meta-analysis.

Methods

Medline, the Cochrane Library, and EMBASE were searched using the following key words: lipid, cholesterol, triglyceride, fat, serum, blood, sudden hearing loss, hearing loss, hearing disorders. Randomized controlled trials, prospective cohort studies, and retrospective case-control studies involving patients with SSNHL and healthy controls that examined the relationship (reported as odds ratios [OR]) between lipid profiles and SSNHL were included. Primary outcomes were total cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations. Secondary outcomes were triglyceride, high-density lipoprotein cholesterol, and lipoprotein(a) concentrations.

Results

A total of 6 case-control studies were included in this systematic review/meta-analysis. The total number of participants ranged from 30 to 250 in the case group and from 43 to 271 in the control group. Meta-analysis revealed no significant difference in total cholesterol levels between the case and control groups (pooled OR = 1.79, 95% confidence interval [CI] = 0.98 to 3.26, P = 0.057). Likewise, meta-analysis revealed no significant difference in LDL-C concentrations between the case and control groups (pooled OR = 1.15, 95% CI = 0.64 to 2.07, P = 0.639). Since there were an insufficient number of studies reporting data for the secondary outcomes, meta-analysis was not possible.

Conclusions

Our results do not provide evidence for serum lipids being associated with SSNHL, nor do they definitively rule out such an association. Additional studies are needed to ascertain the relationship, or lack thereof, between serum lipids and SSNHL.  相似文献   
947.
Mammal Research - Reduction of genetic diversity can lead to reduced fitness of species, such as the loss of adaptability to changing environments. The native Eurasian beaver (Castor fiber) was...  相似文献   
948.
Copper (Cu) offers a means for producing value‐added fuels through the electrochemical reduction of carbon dioxide (CO2), i.e., the CO2 reduction reaction (CO2RR), but designing Cu catalysts with significant Faradaic efficiency to C2+ products remains as a great challenge. This work demonstrates that the high activity and selectivity of Cu to C2+ products can be achieved by atomic‐scale spacings between two facets of Cu particles. These spacings are created by lithiating CuOx particles, removing lithium oxides formed, and electrochemically reducing CuOx to metallic Cu. Also, the range of spacing (ds) is confirmed via the 3D tomographs using the Cs‐corrected scanning transmission electron microscopy (3D tomo‐STEM), and the operando X‐ray absorption spectra show that oxidized Cu reduces to the metallic state during the CO2RR. Moreover, control of ds to 5–6 Å allows a current density exceeding that of unmodified CuOx nanoparticles by about 12 folds and a Faradaic efficiency of ≈80% to C2+. Density functional theory calculations support that ds of 5–6 Å maximizes the binding energies of CO2 reduction intermediates and promotes C–C coupling reactions. Consequently, this study suggests that control of ds can be used to realize the high activity and C2+ product selectivity for the CO2RR.  相似文献   
949.
950.
The effects of the metabolic inhibitors KCN and SHAM on phototaxis and photophobic response in Amoeba proteus have been studied. Both drugs neither change amoebae photophobic response nor the phototactic reaction. The results indicate clearly that the negative phototactic orientation is not impaired by impediment of respiration thus it is not directly coupled to the differences in energy production in different parts of A. proteus body.  相似文献   
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