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81.
BACKGROUND:Gallbladder cancer(GBC)is a rare disease but a leading cause of cancer-related death worldwide.A number of etiological factors have been implicated in the causation of GBC and pathogenic infection by bacteria is one of these. DATA SOURCES:A PubMed search onhelicobacter,gall- bladder cancer,andbiliary tract malignancieswas done on the topic,and the relevant data were collected,reviewed,and analyzed. RESULTS:Helicobacter is an epsilon proteobacterium that infects the mucosal lining of the human gas...  相似文献   
82.

Aim

Gallbladder cancer (GBC) may be associated with Helicobacter pylori. The present study was designed to analyze the association of cytokine expression with H. pylori in patients with GBC.

Methods

GBC tissue sample and 5 mL blood were collected from each of 54 GBC patients. H. pylori was identified in tissue samples using biochemical tests, histology, culture, nested polymerase chain reaction (PCR), and partial genome sequencing. Tissue samples were categorized as H. pylori-positive (case) and H. pylori-negative groups (control) on the basis of nested PCR of tissue sample. Cytokines interleukin 1-β (IL-1β), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and interleukin-5 (IL-5) were assayed in blood samples using ELISA.

Results

Presence of H. pylori was confirmed in 18 (33 %) of 54 GBC tissue samples. Levels of IL-1β (p?=?0.001) and TNF-α (p?=?0.01) were significantly elevated in H. pylori-positive GBC compared to the control group. IFN-γ and IL-5 levels did not significantly differ between the two groups.

Conclusions

H. pylori DNA was detected in the gallbladder of a third of GBC patients and was associated with higher circulating levels of some cytokines.  相似文献   
83.
Molecular markers provide a rapid and relatively inexpensive approach for assessing antimalarial drug susceptibility. We collected 884 Plasmodium falciparum-infected blood samples from 17 Lao provinces. Each sample was genotyped for 11 codons in the chloroquine resistance transporter (pfcrt), dihydrofolate reductase (pfdhfr), and dihydropteroate synthase (pfdhps) genes. The samples included 227 collected from patients recruited to clinical trials. The pfcrt K76T mutation was an excellent predictor of treatment failure for both chloroquine and chloroquine plus sulfadoxine-pyrimethamine, and mutations in both pfdhfr and pfdhps were predictive of sulfadoxine-pyrimethamine treatment failure. In multivariate analysis, the presence of the pfdhfr triple mutation (51 + 59 + 108) was strongly and independently correlated with sulfadoxine-pyrimethamine failure (odds ratio = 9.1, 95% confidence interval = 1.4-60.2, P = 0.017). Considerable geographic heterogeneity in allele frequencies occurred at all three loci with lower frequencies of mutant alleles in southern than in northern Laos. These findings suggest that chloroquine and sulfadoxine-pyrimethamine are no longer viable therapy in this country.  相似文献   
84.
Singh M  Murriel CL  Johnson L 《Cancer research》2012,72(11):2695-2700
The high failure rate of late-stage human clinical trials, particularly in oncology, predicates the need for improved translation of preclinical data from mouse tumor models into clinical predictions. Genetically engineered mouse models (GEMM) may fulfill this need, because they mimic spontaneous and autochthonous disease progression. Using oncogenic Kras-driven GEMMs of lung and pancreatic adenocarcinoma, we recently showed that these models can closely phenocopy human therapeutic responses to standard-of-care treatment regimens. Here we review the successful preclinical application of such GEMMs, as well as the potential for discovering predictive biomarkers and gaining mechanistic insights into clinical outcomes and drug resistance in human cancers.  相似文献   
85.
In the transforming growth factor β (TGF-β) signaling pathway, TGF-β1 and TGF-β receptor 2 (TGF-βR2) are essential regulatory components which play an important role in different type of cancer. Expressions of TGF-β1 and TGF-βR2 were done by real-time qPCR in both biopsy and blood samples collected from esophageal squamous cell carcinoma (ESCC) patients (n = 76). The expression profiles were correlated with different lifestyle factors and clinicopathological parameters. Kaplan-Meier survival analysis and Cox regression analysis were performed to estimate survival and hazard outcomes of different parameters. TGF-β1 showed upregulation in 91% tissue samples (2.84 ± 1.34*) and 55% blood samples (2.43 ± 1.24*) whereas expression of TGF-βR2 showed downregulation in 89% tissue samples (0.27 ± 0.23*) and 75% blood samples (0.30 ± 0.26*). Among all the parameters, TGF-β1 expression is significant with histopathology grade, consumption of betel nut and smoked food whereas TGF-βR2 expression is significant only with dysphagia grade in both blood and tissue samples and while analyzing both male and female patients separately. Consuming alcohol and hot food, difference in tumor stage and metastasis were found to have statistically significant (P < 0.05) impact on survival and mortality of male patients while consuming hot food, tobacco, metastasis and TGF-βR2 expression in tissue level were found to associate with survival and mortality of female patients. Expression of both TGF-β1 and TGF-βR2 in tissue samples may be prospective biomarkers for screening of ESCC among the Northeast population. Survival outcomes and hazard analysis supports the importance of some clinicopathological and lifestyle factors on ESCC development, whereas expression study depicts association of change in expression of the studied genes in ESCC patients.*Mean fold change.  相似文献   
86.
The long-term objective of this work is to understand the mechanisms by which electrical stimulation based movement therapies may harness neural plasticity to accelerate and enhance sensorimotor recovery after incomplete spinal cord injury (iSCI). An adaptive neuromuscular electrical stimulation (aNMES) paradigm was implemented in adult Long Evans rats with thoracic contusion injury (T8 vertebral level, 155 ± 2 Kdyne). In lengthy sessions with lightly anesthetized animals, hip flexor and extensor muscles were stimulated using an aNMES control system in order to generate desired hip movements. The aNMES control system, which used a pattern generator/pattern shaper structure, adjusted pulse amplitude to modulate muscle force in order to control hip movement. An intermittent stimulation paradigm was used (5-cycles/set; 20-second rest between sets; 100 sets). In each cycle, hip rotation caused the foot plantar surface to contact a stationary brush for appropriately timed cutaneous input. Sessions were repeated over several days while the animals recovered from injury. Results indicated that aNMES automatically and reliably tracked the desired hip trajectory with low error and maintained range of motion with only gradual increase in stimulation during the long sessions. Intermittent aNMES thus accounted for the numerous factors that can influence the response to NMES: electrode stability, excitability of spinal neural circuitry, non-linear muscle recruitment, fatigue, spinal reflexes due to cutaneous input, and the endogenous recovery of the animals. This novel aNMES application in the iSCI rodent model can thus be used in chronic stimulation studies to investigate the mechanisms of neuroplasticity targeted by NMES-based repetitive movement therapy.  相似文献   
87.
88.
CA 125: a potential tumor marker for gallbladder cancer   总被引:2,自引:0,他引:2  
BACKGROUND: CA 125 is a glycoprotein and a commonly used tumor marker in ovarian carcinoma. Its use in gallbladder carcinoma (GBC) has not yet been reported. We have henceforth examined for the first time the diagnostic utility of CA 125 in patients with gallbladder diseases. PATIENTS AND METHODS: Serum CA 125 was measured in 64 patients with GBC, 47 Gallstone disease (GSD) and 23 healthy volunteers by ELISA. CA 125 level was compared between different cohorts by non-parametric test (Kruskal Wallis and Mann-Whitney test). Receiver operating characteristic curve (ROC) was constructed to see the diagnostic utility of CA 125. Its level was also correlated with age, sex and clinico-pathological parameters of the patients included in the study. RESULTS: Mean value of CA 125 in patients with GBC, GSD and healthy volunteers was 77.44 +/- 141.31 U/ml, 7.85 +/- 5.40 U/ml, and 8.08 +/- 3.26 U/ml respectively and showed a statistically significant difference (P < 0.001). CA 125 at cut off value of 11 U/ml yielded 64% sensitivity and 90% specificity in differentiating benign from malignant gallbladder disease. CA 125 level increased with stage and grade of the GBC though this was not statistically significant. A higher level of CA 125 was found in presence of gallbladder mass, weight loss, ascites and loss of appetite compared to patients with GSD. No association of CA 125 was apparent with either age or sex of the patients. CONCLUSION: CA 125 has a diagnostic potential for GBC and can differentiate GBC from GSD in light of other clinical details.  相似文献   
89.
Mangiferin, from the leaves of Mangifera indica Linn., has been suggested as useful in the treatment of cardiovascular disorders. In the present study this drug was examined on the alteration of cardiac energy metabolism in isoproterenol (ISPH) administered myocardial infarcted rats. ISPH (20 mg/kg b.w.), which was administered s.c. twice at an interval of 24 h, caused a significant decrease in the activities of TCA cycle enzymes and antioxidant defense enzymes with a concomitant increase in the lipid peroxidation of heart mitochondria in rat model. The ATP production and the oxidation of succinate in State 3 and 4 decreased significantly in the cardiac mitochondria of ISPH administered rats. These functional alterations were supported by severe modifications in mitochondrial ultrastructure. Pretreatment with mangiferin (100 mg/kg b.w. i.p.) for 28 days prevented these mitochondrial alterations, oxidation with energy metabolism and restored the TCA cycle enzyme activities to near normal values following ISPH administration. The structural integrity of the heart was protected by mangiferin in ISPH administered rats when compared to the untreated controls. The present findings suggest that the protective effect of mangiferin can be attributed to its reducing effect on oxidative damage and activation of mitochondrial energy metabolism. These results could be useful to study and understand the cellular events involved in this cardioprotective mechanism of mangiferin. Our studies of mangiferin on heart failure may have important implication for future therapeutic approaches involving in the prevention of cardiovascular diseases.  相似文献   
90.
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