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991.
The Osler-Weber-Rendu syndrome or Hereditary Hemorrhagic Telangiectasia (HHT) is a systemic fibrovascular dysplasia characterized by defects in the elastic and vascular walls of blood vessels, making them varicose and prone to disruptions. Lesions occur in different organs and can lead to hemorrhage in the lungs, digestive tract and brain. We describe the case of a patient with cutaneous manifestations and severe impairment of the digestive tract. It is important for the dermatologist to recognize this syndrome, since the cutaneous lesions may play a key role in diagnosis.  相似文献   
992.
Objective

Investigate the effect of erosive challenge with hydrochloric acid (HCl) on the surface of five different restorative materials.

Material and methods

Ten plates of five restorative materials (Admira Fusion, Activa BioActive-Restorative, Charisma, Equia Forte HT Fil/EF, Filtek Universal Restorative/FU) were obtained. Half of the plate surfaces was covered with an adhesive tape, creating a control area, and the other side was submitted to the HCl (0.06 M HCl; pH 1.2; at 37 °C; for 30 h). Plates with control and HCl-treated areas were analyzed regarding the surface roughness (Sa), roughness profile (Rv), surface loss (SL), microhardness (MI), and gloss (GL) (n?=?10). Surface morphology was analyzed by SEM and chemical elements were identified by EDX (n?=?5). Data were evaluated by ANOVA and Tukey’s test (α?=?0.05).

Results

Most materials were not affected by HCl. FU showed the lowest Sa and Rv, and the highest GL after HCl. On the other hand, EF presented the highest Sa, Rv, and SL, and the lowest GL. The MI of materials was not changed after HCl. Topographical and chemical alterations were observed after HCl only for EF.

Conclusions

The composites showed minor surface changes after HCl, which was not observed for the glass ionomer cement (EF). FU presented the best performance regarding the parameters evaluated.

Clinical relevance

The effects of erosive challenge with HCl on composites were minimal, while the glass ionomer cements might not be indicated as restorative material for patients with gastroesophageal reflux disease.

  相似文献   
993.
994.
995.
Schizophrenia is characterized by a slow deteriorating mental illness. Although the pathophysiology mechanisms are not fully understood, different studies have suggested a role for the immune system in the pathogenesis of schizophrenia. To date, an altered expression or signaling of neurotransmitters receptors is observed in immune cells during psychiatric disorders. In the present study, we investigated the expression of different serotonin and dopamine receptors in T-cells of schizophrenic and control patients. We used flow cytometry to determine the pattern of expression of dopamine (D2 and D4) and serotonine receptors (SR1A, SR1C, SR2A, SR2B), as well as serotonin transporter (ST), in T-cell subsets (CD4 and CD8). Expression of serotonin receptors and ST in T-cells of schizophrenic patients were not different from controls. However, the percentages of CD4+D4+ and CD8+D4+ were increased in schizophrenic patients as compared to controls. In addition, increased percentages of CD8+D2+ cells were also observed in schizophrenic patients, albeit this population revealed lower CD4+D2+ cells in comparison to controls. Interestingly, a relationship between clinical symptoms and immunological parameters was also observed. We showed that the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS) and the Abnormal Involuntary Movement Scale (AIMS) were positively related to CD8+D2+ cells, though AIMS was inversely related to CD4+D4+ cells. In conclusion, the alteration in the pattern of cell population and molecules expressed by them might serve as a promising biomarker for diagnosis of schizophrenia.  相似文献   
996.
This study aimed at analyzing the relationship between slow- and fast-alpha asymmetry within frontal cortex and the planning, execution and voluntary control of saccadic eye movements (SEM), and quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 12 healthy participants performing a fixed (i.e., memory-driven) and a random SEM (i.e., stimulus-driven) condition. We find main effects for SEM condition in slow- and fast-alpha asymmetry at electrodes F3-F4, which are located over premotor cortex, specifically a negative asymmetry between conditions. When analyzing electrodes F7-F8, which are located over prefrontal cortex, we found a main effect for condition in slow-alpha asymmetry, particularly a positive asymmetry between conditions. In conclusion, the present approach supports the association of slow- and fast-alpha bands with the planning and preparation of SEM, and the specific role of these sub-bands for both, the attention network and the coordination and integration of sensory information with a (oculo)-motor response.  相似文献   
997.
998.
In this text we evaluated the in vitro antifungal activities of terbinafine combined with caspofungin, miconazole, ketoconazole, and fluconazole against 17 Pythium insidiosum strains by using the microdilution checkerboard method. Synergistic interactions were observed with terbinafine combined with caspofungin (41.2% of the strains), fluconazole (41.2%), ketoconazole (29.4%), and miconazole (11.8%). No antagonistic effects were observed. The combination of terbinafine plus caspofungin or terbinafine plus fluconazole may have significant therapeutic potential for treatment of pythiosis.Pythiosis is a life-threatening infectious disease in humans and animals that is caused by the aquatic oomycete Pythium insidiosum (9). Horses are the most frequently infected animals, and equine pythiosis typically involves ulcerative granulomas (8). In humans, the infection occurs as ophthalmic, subcutaneous, and systemic forms, which are frequently associated with α- and β-thalassemia (5, 7). Pythiosis therapy, which is based on amphotericin B or azoles, has been ineffective or controversial, and the associated prognosis for human and equine pythiosis is poor (5, 7, 8, 9, 12). Therefore, surgical procedures, including amputation, are often effective, but disease reoccurrence rates are unfortunately high (7).Combinations of antifungal agents against pythiosis have not been thoroughly studied, and therefore, such in vitro combinatory activities against P. insidiosum require attention (1, 6).The purpose of this study was to investigate the in vitro activity of terbinafine (TRB) combined with caspofungin (CAS), miconazole (MNZ), ketoconazole, and fluconazole (FLC) against 17 strains of Pythium insidiosum isolated from animals.A total of 15 Brazilian P. insidiosum strains isolated from equines with pythiosis and two standard strains (ATCC 58637 and CBS 101555) were tested. All strains were maintained in cornmeal agar, and strain identification was confirmed by a PCR-based assay (4).The susceptibility of the P. insidiosum strains to the antifungal agents was tested by microdilution, based on protocol M38-A2 (2). The inoculum consisted of P. insidiosum zoospores obtained following zoosporogenesis. Cell numbers of zoospores were counted on a hemocytometer; zoospores were diluted in RPMI 1640 containing l-glutamine and buffered to pH 7.0 with 0.165 M MOPS (morpholinepropanesulfonic acid) to obtain a final concentration range of 2 × 103 to 3 × 103 zoospores/ml (10).The combinations of TRB (Novartis) plus CAS (Merck), TRB plus MNZ (Labware), TRB plus ketoconazole (Janssen), and TRB plus FLC (Pfizer) were evaluated using the checkerboard technique, according to the broth microdilution design (2, 14). In the individual tests, 100 μl of each drug concentration was plated in microplate wells and an equal volume of the inoculum was added to each well. In the combination tests, the antifungals were plated at a 4× concentrate of 50 μl of drug A plus 50 μl of drug B and 100 μl of the inoculum, resulting in a final 1× drug concentration of each compound. The microplates were incubated at 37°C for 24 h. The MIC was defined as the lowest drug concentration at which there was 100% inhibition of fungal growth by visual readings. The tests were performed in duplicate, and the assay was repeated when disparate values were obtained. The interactions, based on the respective fractional inhibitory concentration index (FICI), were interpreted as the following: FICI ≤ 0.5, synergism; FICI > 0.5 to ≤4, indifference; FICI > 4, antagonism. FICIs were obtained using the formula FICI = (MIC of drug A in combination/MIC of drug A alone) + (MIC of drug B in combination/MIC of drug B alone).The in vitro activities of individual antifungal agents against P. insidiosum are shown in Table Table1.1. In general, the patterns of susceptibility demonstrated that individual drugs had only weak antifungal activity or none.

TABLE 1.

In vitro activities of TRB, CAS, and azoles against isolates of Pythium insidiosum
DrugMIC (mg/liter) (n = 17)
RangeaGMbMIC50MIC90c
TRB8-3214.71632
CAS8-6419.61664
MNZ4-3213.61632
Ketoconazole16-6423.13264
FLC32-6459.06464
Open in a separate windowaRange between the lowest and highest MICs for all isolates.bGM, geometric mean of MIC.cMIC of drug capable of inhibiting the growth of 90% of isolates.The combinations of TRB plus FLC and TRB plus CAS both exhibited synergistic effects against seven (41.2%) P. insidiosum strains. The combination of TRB plus ketoconazole was also synergistic against five (29.4%) isolates, while the combination of TRB plus MNZ exhibited synergistic effects against only two (11.8%) isolates (Table (Table2).2). Antagonistic effects were not indicated.

TABLE 2.

In vitro activity of TRB combined with FLC, MNZ, ketoconazole, or CAS against Pythium insidiosumc
IsolateaTRB and FLC
TRB and MNZ
TRB and ketoconazole
TRB and CAS
MIC of combination (mg/liter)
FICI (interpret.)bMIC of combination (mg/liter)
FICI (interpret.)MIC of combination (mg/liter)
FICI (interpret.)MIC of combination (mg/liter)
FICI (interpret.)
TRBFLCTRBMNZTRBKetoconazoleTRBCAS
LAPEMI 11940.1250.2 (S)40.50.3 (S)40.1250.3 (S)0.510.1 (S)
LAPEMI 12380.1251.0 (I)0.25160.6 (I)0.25161.0 (I)0.2580.6 (I)
LAPEMI 12432642.0 (I)1161.0 (I)0.2510.5 (S)0.25160.5 (S)
LAPEMI 12532642.0 (I)32322.0 (I)32322.0 (I)4160.6 (I)
LAPEMI 12640.1250.5 (S)0.25161.0 (I)480.6 (I)0.2580.6 (I)
LAPEMI 128160.1251.0 (I)0.25161.0 (I)0.2581.0 (I)0.25320.2 (S)
LAPEMI 12980.1251.0 (I)1321.1 (I)480.6 (I)0.2580.6 (I)
LAPEMI 130840.3 (S)0.25162.0 (I)0.2540.5 (S)0.2580.5 (S)
LAPEMI 13580.1250.5 (S)0.250.250.1 (S)0.25160.6 (I)0.2580.6 (I)
LAPEMI 136840.6 (I)0.25161.0 (I)0.250.50.1 (S)0.2540.2 (S)
LAPEMI 138320.1252.0 (I)481.2 (I)840.6 (I)0.25160.6 (I)
LAPEMI 14440.1250.5 (S)0.25161.0 (I)480.6 (I)141.1 (I)
LAPEMI 147320.1252.0 (I)160.251.0 (I)320.1252.0 (I)0.25161.0 (I)
LAPEMI 14816162.0 (I)0.2580.6 (I)0.25161.0 (I)0.250.50.1 (S)
LAPEMI 18740.1250.5 (S)40.250.6 (I)40.1250.5 (S)40.50.5 (S)
ATCC 58637880.7 (I)0.2581.0 (I)0.25161.0 (I)0.2541.0 (I)
CBS 10155580.1250.5 (S)0.2582.0 (I)4160.7 (I)180.6 (I)
Open in a separate windowaLAPEMI, Laboratório de Pesquisas Micológicas; ATCC, American Type Culture Collection; CBS, Centraalbureau voor Schimmelcultures.binterpret., interpretation; S, synergistic; I, indifferent.cn = 17.The use of combination therapy in the treatment of pythiosis could be an alternative to monotherapy (3), but such application would require further investigation. Herein, we examined the in vitro activities of selected antifungal agents singularly or in combination against P. insidiosum.Our results are difficult to interpret, since only a few previous studies investigating the susceptibility of P. insidiosum have been reported, and those studies were performed using different experimental techniques (1, 13). In addition, the breakpoints for susceptibility tests with antifungal agents against P. insidiosum are not defined (2). Therefore, these results suggest relatively weak antifungal activity of the individual agents, which is in accordance with the well-known therapeutic failures in pythiosis treatment. In contrast, the results obtained utilizing drug combinations, which are based on FICIs, can be interpreted with more confidence for activity.Studies focusing on the use of combination therapy against P. insidiosum are almost nonexistent. The first report on the potential synergistic effects of TRB plus itraconazole was that by Shenep et al. (13), which involved the successful treatment of deeply invasive facial infections from P. insidiosum infection in a child with this combination therapy.Argenta et al. (1) reported that the combination of TRB and either itraconazole or voriconazole was synergistic against 17% of the strains tested and no antagonistic effects were observed. In this study, we demonstrated significant synergistic effects, as the combinations of TRB plus FLC and TRB plus CAS were synergistic against 41.2% of P. insidiosum strains. Additionally, synergistic effects were indicated with combinations of TRB plus ketoconazole and TRB plus MNZ, albeit to a lower extent (against 29.4% and 11.8% of strains, respectively). To our knowledge, the synergistic effects of these antifungals against P. insidiosum are being reported for the first time in this study, and antagonistic effects of these combination antifungal treatments were not observed.However, a concern for the use of combination antifungal therapy in treating P. insidiosum infection is the great variation in susceptibility among the different strains, which may be related to the genetic variability of the strains tested (11). However, our in vitro results demonstrate that combination antifungal therapy may be an alternative in the treatment of P. insidiosum. In vivo studies must be further investigated experimentally, since 48.5% of the combined MICs were lower than the serum concentrations achieved by the respective agents, which indicates the potential therapeutic utility of our results.  相似文献   
999.
PURPOSE: To study the possibility of using independent component analysis (ICA) to identify breast lesions as separate hemodynamic sources on dynamic contrast-enhanced (DCE) MR images, as depicted by the passage of contrast medium. MATERIALS AND METHODS: Six patients who were histopathologically confirmed with breast carcinoma underwent DCE MRI with 5 precontrast and 60 postcontrast scans at a time-resolution of 8 s. A spatial ICA algorithm was applied on the DCE MRI data set to extract spatial component maps corresponding to source locations with different signal time-intensity patterns. To verify the present hypothesis of the ability of ICA to reveal tumor voxels as a separate hemodynamic phase, tumor margins were outlined by an experienced radiologist who was blinded from the ICA results, and the manual outlines were compared with the ICA maps. RESULTS: Consistently for each of the six patient study cases, it was found that ICA yields a tumor component map associated with typical tumor enhancement patterns of rapid enhancement with washout or plateau. Tumor outlines manually drawn by the radiologist were in good agreement with the tumor locations depicted in the tumor component maps. CONCLUSION: ICA may provide an objective method for identifying the outlines of enhancing breast tumors on DCE MR images and to automatically extract the tumor signal intensity-time curve for subsequent tracer kinetics analysis.  相似文献   
1000.
Two vitamins and proline (CB6Pro), three nutrients essential for bone collagen, were used in combination to a 1000 mg calcium/250 IU vitamin D (Ca/D) daily supplement to treat osteopenia as a preventive measure against osteoporosis later in life. Middle-aged women not using estrogen were screened for osteopenia using the WHO criteria and divided into three groups (n = 20 each): 1) placebo healthy controls with normal bone mineral density (BMD); 2) control Ca/D-treated osteopenic patients; and 3) Ca/D + CB6Pro-treated osteopenic patients. The three groups were comparable at baseline except for BMD. After one-year treatment, cortical diaphyseal BMD remained constant in each group, but trabecular bone loss persisted (at 5 lumbar sites) in osteopenic group 2. No further bone loss was detected in osteopenic group 3. A loss of 2% was evidenced in the placebo group at one lumbar site. Markers of bone formation (which increase in coupling to resorption) decreased significantly in both osteopenic groups. Although biomarkers of resorption did not change, hormone (PTH and 1,25(OH)2D3)-induced osteoclastic activity was significantly reduced. No decline in BMD occurred at any bone site in osteopenic group 3, highlighting the importance of improving the quality of bone matrix concomitantly to mineral replacement.  相似文献   
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