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1.
In order to investigate the clinical factors that might influence the diversity and the degree of Candida species carriage in saliva, we conducted a cross-sectional study with 133 patients with complaints of xerostomia. Anamnesis, oral examination and collection of chewing-stimulated whole saliva were performed. The samples of saliva were kept refrigerated until they were plated onto CHROMagar Candida; cfu were counted and Candida species were identified by standard methods. There was a high prevalence of mixed Candida colonization. No relationship was found between total Candida cfu counts and variables like gender, age, place of origin, underlying diseases, exposure to medications (except antibiotics), daily habits and salivary flow rates. Oral candidiasis, antibiotic exposure and dental prosthesis wearing were associated with relatively high Candida counts in saliva. Low salivary flow rates predisposed to intense colonization by C. albicans and C. parapsilosis.  相似文献   
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In this study, our objective was to evaluate Etest strips containing exponential gradients of isoniazid (INH), rifampin (RIF), and streptomycin (STR) for susceptibility testing of Mycobacterium tuberculosis. M. tuberculosis isolates were tested for antimicrobial susceptibilities by the standard proportion method using L?wenstein-Jensen (LJ) medium and by the Etest. The MICs determined by the Etest were obtained at 5, 7, or 10 days. In some strains with Etest-discrepant results, radiometric susceptibility testing (BACTEC) was performed to determine a consensus result. M. tuberculosis concordance between the two methods was 97% (86 of 89 isolates) for RIF, 96% for INH (84 of 87 isolates), and 80% (61 of 76 isolates) for STR. Most of the MICs determined by the Etest were easy to interpret and readable within 5 days. Results correlated well with those obtained by the LJ proportion and BACTEC methods for INH and RIF. However, a high proportion of false-sensitive and false-resistant results were observed, most often for STR. We also observed that variations in the inoculum size of M. tuberculosis isolates affected the MICs to a substantial degree. These discrepancies, along with the expense of the media, the Etest strips, and the specialized equipment required (CO2 incubator), make this method less useful in developing countries.  相似文献   
3.
Samples of herbal medicine used in Brazil were analyzed, after nitric digestion, for the content of cadmium, mercury and lead, by atomic absorption spectrophotometry. Fifteen samples of ginkgo biloba (Ginkgo biloba), 13 of celastraceae (Maytenus ilicifolia), 14 of cascara buckthorn (Rhamnus purshiana), 13 of eggplant (Solanum melongena), 15 of horse chestnut (Aesculus hippocastanum), 13 of Brazilian ginseng (Pffafia glomerata), 17 of centella asiatic (Hydrocotyle asiatica), 13 of guarana (Paullinia cupana), 12 of artichoke (Cynara scolymus) and five samples of chlorella (Chlorella pyrenoidosa) were analyzed. Cadmium, mercury and lead were not detected (limit of quantifications of 0.20, 0.01 and 2.0 mg/kg, respectively) in any sample of artichoke, eggplant and guarana. Cadmium was found in samples of the other medicinal herbs at levels up to 0.74 microg/g and mercury up to 0.087 microg/g. Three samples of horse chestnut contained 153, 156 and 1480 microg Pb/g, while the highest concentration found in the other samples analyzed was 22 microg Pb/g. The estimated lead intake through the consumption of horse chestnut reached 440% of Provisional Tolerable Weekly Intake (PTWI), and might be of concern to consumers if the medicine was taken on a long-term basis. Cadmium and mercury exposure through the herbal medicines does not appear to be of health concern.  相似文献   
4.
This study evaluated whether the use of continuous positive airway pressure (CPAP) in the delivery room alters the need for mechanical ventilation and surfactant during the first 5 days of life and modifies the incidence of respiratory morbidity and mortality during the hospital stay. The study was a multicenter randomized clinical trial conducted in five public university hospitals in Brazil, from June 2008 to December 2009. Participants were 197 infants with birth weight of 1000-1500 g and without major birth defects. They were treated according to the guidelines of the American Academy of Pediatrics (APP). Infants not intubated or extubated less than 15 min after birth were randomized for two treatments, routine or CPAP, and were followed until hospital discharge. The routine (n=99) and CPAP (n=98) infants studied presented no statistically significant differences regarding birth characteristics, complications during the prenatal period, the need for mechanical ventilation during the first 5 days of life (19.2 vs 23.4%, P=0.50), use of surfactant (18.2 vs 17.3% P=0.92), or respiratory morbidity and mortality until discharge. The CPAP group required a greater number of doses of surfactant (1.5 vs 1.0, P=0.02). When CPAP was applied to the routine group, it was installed within a median time of 30 min. We found that CPAP applied less than 15 min after birth was not able to reduce the need for ventilator support and was associated with a higher number of doses of surfactant when compared to CPAP applied as clinically indicated within a median time of 30 min.  相似文献   
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Purpose: This study employed three‐dimensional (3D) finite element analysis to investigate the stress distribution patterns in a microtensile test with the goal of evaluating the effects of the bond surface area and geometry on bond strength. Materials and Methods: Finite element models of six specimens were generated: three stick models and three hourglass models. All models simulated the bond strength between dentin and ceramic. The mechanical properties of the materials—the modulus of elasticity and Poisson's coefficient—were defined according to a literature review. The base of each specimen was considered inserted (constrained area) and possessed nodes with displacements restricted in all directions. A traction load, which was calculated to generate a uniformly distributed stress of 20 N/mm2 at the bond interface, was applied to the top of the specimen. The distribution pattern of the generated stress was qualitatively and quantitatively measured based on color scales ranging from blue to red, according to the von Mises equivalent stress. Results: Specimens with similar shapes demonstrated similar stress distributions. Ceramic specimens had a higher stress value (30.35 MPa) compared to specimens consisting of resinous cement (23.59 MPa) and dentin (19.77 MPa). At the bond interface, the specimens with square sections demonstrated stress values ranging from 22.00 to 24.20 MPa. For the circular section, the stress values ranged from 23.40 to 27.00 MPa. Conclusion: The maximum stress values determined for the circular and square sections were similar among specimens with the same interface area. At the bond interface, the highest stress values were observed in hourglass‐shaped specimens.  相似文献   
10.
Opportunistic infections in endogenous Cushing's syndrome are associated with severe cortisol excess and carry a high mortality. Pulmonary cryptococcosis is one of these opportunistic infections and can mimic a lung neoplasm, therefore making its diagnosis difficult. We report a case of a young male with ACTH-dependent Cushing's syndrome and severe hypercortisolism. The patient achieved cure after the transfenoidal surgery, but developed a febrile state. A chest computed tomography showed a pulmonary nodule that did not change in serial chest radiographs. Diagnosis of tuberculosis, fungal and bacterial infections were inconclusive, so the hypothesis of lung neoplasm became more probable. The necropsy, however, disclosed a pseudotumoral cryptococcosis. Opportunistic infections, like Cryptococcus neoformans, should be considered in patients with Cushing's syndrome and a pulmonary infiltrate.  相似文献   
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