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71.
Hyponatremia is an important and common electrolyte disorder in tumor patients and one that has been reported in association with a number of different primary diagnoses. The correct diagnosis of the pathophysiological basis for each patient is important because it significantly alters the treatment approach. In this article, we review the epidemiology and presentation of patients with hyponatremia, the pathophysiologic groups for the disorder with respect to sodium and water balance and the diagnostic measures for determining the correct pathophysiologic groups. We then present the various treatment options based on the pathophysiologic groups including a mathematical approach to the use of hypertonic saline in management. In cancer patients, hyponatremia is a serious comorbidity that requires particular attention as its treatment varies by pathophysiologic groups, and its consequences can have a deleterious effect on the patient's health.  相似文献   
72.
Concentrations of the calcium-binding proteins of the S100 family, myeloid-related proteins 8 and MRP 14 (MRP8/14), are elevated in chronic infections, yet the role of these proteins is not clearly defined. Using commercial and developed enzyme immunoassays, we assayed for MRP8/14 in sterile-filtered abscess fluid from tissue-cage-implanted rats and rabbits. Staphylococcus aureus abscesses were created 6 weeks after the intraperitoneal implantation of tissue cages. Leukocytes, bacteria, and non-protein-bound calcium and zinc were measured in the infection exudate at day 3 or 5 of infection and after 8 days of treatment with antimicrobials beta-lactams (18 rabbits, 35 rats) and fluoroquinolone-rifampin (6 rabbits). Half of the infected rats were depleted of neutrophils; these rats exhibited significantly lower MRP 8/14 concentrations on all days sampled, regardless of the level of infection. The level of abscess MRP 8/14 is high early in the course of infection but decreases with effective antimicrobial treatment by as much as 100-fold. Thirty-day-old abscesses with log 6 bacterial counts and low neutrophil counts showed low concentrations of MRP 8/14 in these models. In abscess fluid, interleukin-6, as a representative marker of inflammation, correlated with MRP8/14, whereas ionized calcium and zinc did not. Our data suggest that infection and inflammation are not equal stimuli for MRP 8/14. The neutrophil appears to be the main source of MRP8/14 in this model.  相似文献   
73.
74.

Background

The use of doxorubicin (DOX) an anthracycline antineoplastic agent is withdrawn due to its cardio-toxic side effects. Oxidative stress has been recognized as the primary cause of DOX induced cardiotoxicity. We have investigated whether polyphenol rich ethyl acetate extract of Acacia hydaspica (AHE) can attenuate doxorubicin-induced cardiotoxicity via inhibition of oxidative stress.

Methods

AHE was administered orally to rats once daily for 6 weeks at doses of 200 and 400 mg/kg b.w. DOX (3 mg/kg b.w. i.p., single dose/week) was administered for 6 weeks (chronic model). The parameters studied to evaluate cardioprotective potential were the serum cardiac function biomarkers (CK, CKMB, AST and LDH), hematological parameters, cardiac tissue antioxidant enzymatic status and oxidative stress markers, and histopathological analysis to validate biochemical findings.

Results

Chronic 6 week treatment of DOX significantly deteriorated cardiac function biomarkers and decreased the activities of antioxidant enzymes, whereas significant increase in oxidative stress biomarkers was noticed in comparison to control group. AHE dose dependently protected DOX-induced leakage of cardiac enzymes in serum and ameliorated DOX-induced oxidative stress; as evidenced by decreasing lipid peroxidation, H2O2 and NO content with increase in phase I and phase II antioxidant enzymes. Doxorubicin treatment produced severe morphological lesions, leucopenia, decrease in red blood cell counts and hemoglobin concentrations. AHE co-treatment protected the heart and blood elements from the toxic effects of doxorubicin as indicated by the recovery of hematological parameters to normal values and prevention of myocardial injuries in a dose dependent way. The protective potency of AHE (400 mg/kg b.w) was equivalent to silymarin.

Conclusion

Results revealed that AHE showed protective effects against DOX induce cardiotoxicity. The protective effect might attribute to its polyphenolic constituents and antioxidant properties. AHE might be helpful in combination therapies as safer and efficient.
  相似文献   
75.
A one pot approach has been explored to synthesize crosslinked beads from chitosan (CS) and carboxymethyl cellulose (CM) using arginine (ag) as a crosslinker. The synthesized beads were characterized by FTIR, SEM, EDX, XRD, TGA and XPS analysis. The results showed that CS and CM were crosslinked successfully and the obtained material (beads) was analyzed for adsorption of Cd(ii) and Pb(ii) by using batch adsorption experiments; parameters such as temperature, contact time, pH and initial ion concentration were studied. Different kinetic and thermodynamic models were used to check the best fit of the adsorption data. The results revealed that the kinetics data of the adsorption of Pb(ii) and Cd(ii) ions shows the best fit with the pseudo second order model whereas the thermodynamics data shows the best fit with the Langmuir isotherm with maximum adsorption capacities of 182.5 mg g−1 and 168.5 mg g−1 for Pb(ii) ions Cd(ii) ions, respectively. For the recovery and the regeneration after the one use of the beads, several adsorption–desorption cycles were carried out to check the reusability and recovery of both the metal ion and the adsorbent without the loss of maximum adsorption efficiency.

Remediation of Pb(ii) and Cd(ii) containing wastewater by arginine crosslinked chitosan/carboxymethyl cellulose beads.  相似文献   
76.
77.
Serological differentiation of inflammatory bowel diseases   总被引:2,自引:0,他引:2  
OBJECTIVE: In order to shorten the diagnostic procedures simple serological tests with high diagnostic value for Crohn's disease and ulcerative colitis are required. The aim of this study was therefore to evaluate the diagnostic value of a newly developed assay for the determination of antibodies to mannan of Saccharomyces cerevisiae in combination with antibodies to antigens of exocrine pancreas, goblet cells, human neutrophils and tissue transglutaminase. METHODS: Sera from 112 patients with Crohn's disease (82 confirmed and 30 suspected cases), 65 patients with ulcerative colitis, 13 patients with indeterminate colitis, 212 patients with other diseases and 250 healthy blood donors were tested for IgA and IgG antibodies to mannan of S. cerevisiae and IgA to tissue transglutaminase by enzyme-linked immunoassays. Endomysial IgA antibodies and antibodies to antigens of exocrine pancreas, goblet cells and human neutrophils were determined by indirect immunofluorescence. Sensitivity, specificity, positive and negative predictive values of antibodies to mannan of S. cerevisiae and different antibody combinations were determined regarding the diagnosis of Crohn's disease and ulcerative colitis. RESULTS: Antibodies to mannan of S. cerevisiae were detected in 50% of confirmed and 27% of patients suspected of having Crohn's disease. Among patients who did not have Crohn's disease only those suffering from gluten-sensitive enteropathy and primary biliary cirrhosis exhibited antibodies to mannan of S. cerevisiae (14%, 6%). With respect to antibody positivity, antibodies to mannan of S. cerevisiae and/or antibodies to antigens of exocrine pancreas combined with tissue transglutaminase antibody negativity yields a sensitivity, specificity, positive and negative predictive value of 60%, 100%, 100% and 90%, respectively, regarding diagnosis of Crohn's disease. CONCLUSIONS: Determination of antibodies to mannan of S. cerevisiae as a new marker for Crohn's disease is helpful for the differential diagnosis of inflammatory bowel disease. In combination with other established serological markers, antibodies to mannan of S. cerevisiae improve their diagnostic and predictive values considerably.  相似文献   
78.

Introduction

Few tools predict survival from pancreatic cancer (PAC). The McGill Brisbane Symptom Score (MBSS) based on symptoms at presentation (weight loss, pain, jaundice and smoking) was recently validated. The present study compares the ability of four strategies to predict 9-month survival: MBSS, carbohydrate antigen 19-9 (CA 19-9) alone, CA19-9-to-bilirubin ratio and a combination of MBSS and the CA19-9-to-bilirubin ratio.

Methodology

A retrospective review of 133 patients diagnosed with PAC between 2005 and 2011 was performed. Survival was determined from the Quebec civil registry. Blood CA 19-9 and bilirubin values were collected (n = 52) at the time of diagnosis. Receiver-operating characteristic (ROC) curves were used to determine a cutoff for optimal test characteristics of CA 19-9 and CA19-9-to-total bilirubin ratio in predicting survival at 9 months. Predictive characteristics were then calculated for the four strategies.

Results

Of the four strategies, the one with the greatest negative predictive value was the MBSS: negative predictive value (NPV) was 90.2% (76.9–97.3%) and the positive likelihood ratio (LR) was the greatest. The ability of CA 19-9 levels alone, at baseline, to predict survival was low. For the CA19-9-to-bilirubin ratio, the test characteristics improved but remained non-significant. The best performing strategy according to likelihood ratios was the combined MBSS and CA19-9 to the bilirubin ratio.

Conclusion

CA19-9 levels and the CA19-9-to-bilirubin ratio are poor predictors of survival for PAC, whereas the MBSS is a far better predictor, confirming its clinical value. By adding the CA19-9-to-bilirubin ratio to the MBSS the predictive characteristics improved.  相似文献   
79.
Background/PurposeThe effects of ProSeal laryngeal mask airway (PLMA) removal and tracheal extubation on cardiovascular responses were studied in elderly hypertensive patients in a randomized double-blind study.MethodsA total of 60 elderly hypertensive American Society of Anesthesiologists I–II patients were randomly allocated to two groups (n = 30 of each) for PLMA insertion or endotracheal intubation. A standardized anesthetic sequence was used for induction and maintenance of anesthesia. The two groups were then compared for pressor response at the time of extubation/PLMA removal.ResultsIn PLMA group, heart rate and rate pressure product increased during PLMA removal but remained elevated for only 3 minutes while mean arterial pressure remained elevated for only 2 minutes. The elevations of heart rate, mean arterial pressure, and rate pressure product were exaggerated in the extubation group and persisted for more than 5 minutes. No complication was observed in any patient and no difficulty was encountered in insertion of PLMA in any patient.ConclusionElderly hypertensive patients are at risk of exaggerated pressor response at the time of extubation. PLMA removal is associated with fewer hemodynamic changes than tracheal extubation and should be preferred wherever possible.  相似文献   
80.
We present a 6‐year‐old child with intraocular and extraocular mass and high intraocular pressure. The tumor mass involved a disorganized anterior segment and extended through the medial cornea and sclera. A preliminary diagnosis of retinoblastoma with extraocular extension was made. An exenteration of the left globe and orbital tissue was performed. Histological examination showed that the lesion, which occupied the posterior chamber, involved the ciliary body, extending into the iris, sclera and cornea, projecting beyond the cornea anteriorly and extending to the retina posteriorly. The tumor cells were diffusely immunoreactive to vimentin, neuron specific enolase and CD 138. The medulloepithelioma cells were focally positive to cytokeratin (AE1/AE3), cytokeratin 18, CD56,CD57, S100, HMB‐45 and bcl2 while areas of retinoblastic differentiation showed diffuse immunoreactivity to synaptophysin, neurofilament and CD138 with focal immunoreactivity to calretinin. All tumor cells showed no immunoreactivity to cytokeratin 7, cytokeratin 20, epithelial membrane antigen, carcinoembryonic antigen, desmin, GFAP, and chromogranin. Nuclear staining for P53 was seen in 80% of tumor cells. The ki‐67 index was 90%. The tumor was described as malignant intraocular non‐teratoid medulloepithelioma with retinoblastic differentiation arising from the ciliary body. Tumor satellites were seen in the adjacent periocular soft tissue. The treatment involved exenteration of the left globe and orbital tissue with secondary skin graft following chemotherapy. The patient is well and has no recurrence after 1 year of treatment. We report that medulloepithelioma can present as a case of infantile glaucoma, can show signs of intraocular calcifications and can show retinoblastic differentiation.  相似文献   
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