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991.
In this study, our four patients with angiofibroma with various atypical features are presented. Related literature is reviewed and criteria for atypicality are proposed. 14 patients, diagnosed and treated for angiofibroma in the Otorhinolaryngology Department of Faculty of Medicine in Uludag University between January 1992 and December 2003, have been evaluated. The files of the patients were examined and four patients with atypical characteristics have been included in the study. Angiofibromas presenting with at least one of the following criteria such as origin or location other than nasopharynx, presenting complaints other than nasal obstruction or epistaxis, aged younger than seven or older than 25, female sex, atypical histopathology and multifocalitiy were considered as "atypical". Four of 14 angiofibromas (28.5%), which were diagnosed and treated in our clinic, had atypical features. The reasons for atypicality were unusual localization in three patients and uncommon initial symptom in one case. In the atypical localization group, neoplasm was located in tonsil in one case, and in inferior turbinate in two patients. The only patient with atypical initial symptom presented with a bulging in the cheek. The patients, who have different characteristics other than classical angiofibromas, may be called "Atypical Angiofibroma (AAF)", under the scope of the related literature and our experience. These patients should be included in atypical group according to the characteristics such as, localization, symptom, age, sex, histopathology and multifocality.  相似文献   
992.
The bcl-3 gene at chromosome 19q13 encodes a member of the IkB family involved in regulating the nuclear factor kB pathway. Originally identified by its involvement in the t(14:19)(q32;q13), bcl-3 expression recently has been reported in 12% of non-Hodgkin lymphomas and 41% of Hodgkin lymphomas. Because the t(14;19) is detected most commonly in chronic lymphocytic leukemia (CLL), we assessed for bcl-3 expression using immunohistochemical analysis in 72 CLL cases with immunophenotypic and cytogenetic data. Of 72 CLL cases, 12 (17%) were bcl-3+. Expression of bcl-3 correlated with an atypical immunophenotype, defined using the World Health Organization scoring system. Expression also correlated with trisomy 12 and chromosome 19 abnormalities but was not limited to cases with the t(14:19)(q32;q13). Although the mechanism of bcl-3 expression is unclear, these results raise the possibility that bcl-3 may be involved in the pathogenesis of this subset of tumors and could be a potential target for investigational therapies.  相似文献   
993.
Gaucher disease, the inherited deficiency of glucocerebrosidase, is characterized by significant genetic and phenotypic heterogeneity. At the extreme end of the phenotypic continuum is the perinatal lethal variant, typically presenting in utero or during the neonatal period as hydrops and/orcongenital ichthyosis, with severe and progressive neurological involvement. Insights from the null-allele Gaucher mouse model contributed to the identification of this distinct phenotype, which has unique epidermal involvement. While multiple mutations are encountered, many affected infants are homozygous for recombinant alleles. The diagnosis is often missed due to the early lethality and the failure to recognize the association between lysosomal disorders and hydrops fetalis. The incidence of severe perinatal Gaucher disease may prove more common than currently appreciated with greater physician awareness of the disorder.  相似文献   
994.
Parkinson's disease (PD) is a progressive neurological condition with debilitating symptoms, and depression is a common comorbid condition of this disease. The authors review existing literature on the prevalence and treatment of depression in PD. Prevalence estimates of depression vary widely, ranging from 7%-76%. This variation is due to inconsistent methodology. Treatment options for depression in PD include medication therapy, electroconvulsive therapy (ECT), and psychotherapy. There are few randomized controlled trials of these treatment options. The authors argue for more systematic and controlled research examining both the prevalence and treatment of depression in PD.  相似文献   
995.
Background and purpose: The aim is to assess the magnetic resonance imaging (MRI) findings for cranial bone marrow (CBM) signal intensity and thickness in patients with chronic anemia and compared these with findings in healthy subjects. We also investigated the relationships between CBM changes and age, type of anemia (hemolytic versus non-hemolytic), and severity of anemia. Methods: We quantitatively evaluated CBM signal intensity and thickness on images from 40 patients with chronic anemia (20 with congenital hemolytic anemia (HA) and 20 with acquired anemia) and compared these to findings in 28 healthy subjects. The intensity of CBM relative to scalp, white matter (WM), gray matter (GM), and muscle intensity was also investigated in patients and subjects in the control group. The sensitivity and specificity of CBM hypointense to GM and CBM hypointense to WM as markers of anemia were evaluated. Relationships between age and CBM thickness/intensity, and between anemia severity (hemoglobin (Hb) level) and CBM thickness/intensity were evaluated. Results: Cranial bone marrow signal intensity was lower in the chronic anemia patients than in the controls (P<0.001). In the control group, CBM intensity was higher than GM intensity, whereas the opposite was true in the patient group. The finding of CBM hypointense to GM was 85% sensitive and 67% specific as a marker of anemia. The corresponding statistics for CBM hypointense to WM were 90 and 46%. The patients had thicker CBM than the controls (temporal, P<0.05; parietal, P<0.005). The subgroup with hemolytic anemia had thicker parietal CBM than the subgroup with non-hemolytic anemia (NHA) (P<0.05) and exhibited thicker temporal and parietal CBM than the controls (temporal, P<0.05; parietal, P<0.001). The CBM thicknesses in the non-hemolytic anemia subgroup were similar to control values (P>0.05 for both). There were no correlations between age and CBM intensity or thickness, or between anemia severity and CBM intensity or thickness. Conclusion: Patients with chronic anemia exhibit lower CBM signal intensity on MRI than healthy subjects. Patients with hemolytic anemia have thicker CBM than patients with non-hemolytic anemia or healthy individuals. Decreased CBM intensity may indicate that the patient has anemia, and increased CBM thickness may specifically point to hemolytic anemia. These MRI findings may signal the need for further evaluation for the clinician.  相似文献   
996.
In this study, the effect of clarithromycin on the destruction of bacterial biofilm in Pseudomonas aeruginosa osteomyelitis was investigated. Foreign body-related osteomyelitis caused by ceftazidime-sensitive Pseudomonas aeruginosa was produced in the tibias of 26 rats. After osteomyelitis was verified on Day 14, 10 rats had ceftazidime (1500 mg/kg/day) given subcutaneously, and 10 rats had ceftazidime given subcutaneously and clarithromycin (100 mg/kg/day, two 50-mg/kg doses every 12 hours) given orally; three rats formed the control group. After a treatment period of 20 days, the tibias and the foreign bodies were removed, cultured, and examined by electron microscopy. The number of microorganisms growing on the bone tissue in the group receiving combined treatment was significantly lower than in the other groups. The number of microorganisms growing on the foreign body in the group receiving only ceftazidime was significantly higher than that of the group receiving combined treatment. Electron microscope examination revealed that the biofilm layer was eradicated in the group that had combined therapy; however, biofilm formation was evident on the foreign body in the group receiving only ceftazidime. Clarithromycin enhanced the activity of concomitantly used bactericidal agents by destroying biofilm on the surface of the materials.  相似文献   
997.
Free radicals and oxidative damage play roles in aging and age-related ocular diseases such as cataracts, so defensive mechanisms become important factors for protection. Because N-acetylation is involved in a wide variety of detoxification processes, this study was conducted to examine the relationship between the acetylator phenotypes and genotypes in a group of patients with age-related cataract. Sixty-one cases of age-related cataract and 104 controls were included in this study. Blood was collected in EDTA-containing tubes, and genomic DNA was extracted from the white blood cells by high pure PCR template preparation kit. Genotyping of NAT2 polymorphisms were detected by using a LightCycler-NAT2 mutation detection kit in real-time PCR. There was a significant difference in the distribution of the NAT2*6A acetylator phenotype between cases and the controls. The odds ratio of cataract for the NAT2*6A slow phenotype was 3.8 (95% CI = 1.08 to 13.11, p = 0.032) compared with the fast type. Our results suggest that slow acetylators are at higher risk of developing age-related cataracts than fast acetylators. As NAT2 is an important xenobiotic-metabolizing enzyme and theoretically xenobiotics such as ultraviolet B radiation, smoking, and alcohol use may induce cataract formation, NAT2 gene polymorphisms may be associated with genetic susceptibility of cataract.  相似文献   
998.
PURPOSE: Caffeic acid phenethyl ester (CAPE) has antimicrobial, anti-inflammatory, antioxidant, immunomodulatory, and carcinostatic properties. In this study, the efficacy of CAPE in endotoxin-induced uveitis (EIU) in rats is investigated. METHODS: EIU was induced by a footpad injection of lipopolysaccharide (LPS). In the treatment group, 10 micromol/kg CAPE was injected intraperitoneally immediately after LPS injection. At 24 hr after LPS injection, the number of infiltrating cells, protein concentration, and levels of myeloperoxidase (MPO) in aqueous humor; malondialdehyde (MDA), MPO, and total antioxidant levels in serum were determined. Eyes were enucleated for histopathologic evaluation, and, counting inflammatory cells in iris-ciliary body (ICB), the efficacy of treatment was determined. RESULTS: CAPE significantly suppressed LPS-induced increase in the number of inflammatory cells (p = 0.0001), protein concentration (p = 0.0001), and MPO levels (p = 0.0001) in aqueous humor as well as MDA (p = 0.001) and MPO (p = 0.0001) levels in serum. Histopathologic evaluation of ICB showed significant reduction in the inflammatory cell counts in the treatment group (p = 0.0001). CONCLUSIONS: CAPE was found efficient in suppressing inflammation and ocular tissue damage induced by LPS in rats.  相似文献   
999.
In this study, a series of twelve novel 5-[2-(morpholin-4-yl)acetamido] and/or 5-[2-(4-substituted pip-erazine-1-yl)acetamido]-2-(p-substituted phenyl]benzoxazole derivatives have been synthesized and their structures were confirmed by IR, (1)H NMR, and mass spectral data. These compounds were prepared by reacting 5-(2-chloroacetamido)-2-(4-p-substituted-phenyl)benzoxazoles, which were obtained by using 5-amino-2-[p-substituted-phenyl]benzoxazoles with chloroacetyl chloride, in the presence of morpholine or 1-substituted piperazines. All synthesized compounds 3-14 were tested by using the method of twofold serial dilution technique for in vitro activities against certain strains of Gram-positive, Gram-negative bacteria as well as the yeasts Candida albicans, Candida krusei, and Candida glabrata in comparison with standard drugs. Microbiological results showed that the newly synthesized compounds possessed a broad spectrum of activity, showing MIC values of 3.12-50 mug/mL against the Candida species.  相似文献   
1000.
BACKGROUND: To evaluate the relationship between the serum oxidant-antioxidant balance and the presence of exfoliation syndrome (XFS) in a prospective study. METHODS: The study group comprised 27 cases of XFS. Serum concentrations of myeloperoxidase, malondialdehyde, vitamins A, C and E, catalase and total antioxidant were measured and compared with an independent group by t-test. RESULTS: Serum myeloperoxidase, vitamins A and E, catalase and total antioxidant parameters were not statistically different among the groups (P >0.05). Serum vitamin C concentrations were significantly lower and malondialdehyde concentrations were significantly higher in cases of XFS when compared with the control group (P=0.008 and P=0.002, respectively). CONCLUSION: An altered oxidant-antioxidant balance may play a role in the pathogenesis of XFS.  相似文献   
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