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991.
In Brazil, Salmonella enterica serovar Infantis resistant to various antimicrobials, including cephalosporins, has been identified as an etiological agent of severe gastroenteritis in hospitalized children since 1994. In this study, 35 serovar Infantis strains, isolated from children admitted to four different Rio de Janeiro, Brazil, hospitals between 1996 and 2001, were characterized by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing in order to determine their genetic relatedness and antimicrobial resistance profiles. Thirty-four serovar Infantis strains were resistant to at least two antibiotic classes, and all 35 strains were susceptible to fluoroquinolones, cephamycin, and carbapenem. Extended-spectrum beta-lactamase (ESBL) screening by double-disk diffusion indicated that 32 serovar Infantis strains (91.4%) produced beta-lactamases that were inhibited by clavulanic acid. Antimicrobial resistance gene profiles were determined by PCR for a subset of 11 multidrug-resistant serovar Infantis strains, and putative ESBLs were detected by isoelectric focusing. Ten serovar Infantis strains carried bla(TEM), catI, ant(3")Ia and/or ant(3")Ib, sulI and/or sulII, and tet(D) genes as well as an integron-associated aac(6')-Iq cassette. Eight strains possessed at least four different beta-lactamases with pI profiles that confirmed the presence of both ESBLs and non-ESBLs. Our PFGE profiles indicated that 33 serovar Infantis strains isolated from Rio de Janeiro hospitals came from the same genetic lineage.  相似文献   
992.
Heat shock proteins (HSPs) are highly conserved among different organisms. A mycobacterial HSP65 DNA vaccine was previously shown to have prophylactic and immunotherapeutic effects against Mycobacterium tuberculosis infection in mice. Here, BALB/c mice were immunized with mycobacterial DNA-hsp65 or with DNA-hsp65 and trehalose dymicolate (TDM), both carried by biodegradable microspheres (MHSP/TDM), and challenged with Leishmania (Leishmania) major. MHSP/TDM conferred protection against L. major infection, as indicated by a significant reduction of edema and parasite loads in infected tissues. Although high levels of interferon-γ and low levels of interleukin (IL)-4 and IL-10 were detected in mice immunized with DNA-hsp65 or MHSP/TDM, only animals immunized with MHSP/TDM displayed a consistent Th1 immune response, i.e., significantly higher levels of anti-soluble Leishmania antigen (SLA) immunoglobulin G (IgG)2a and low anti-SLA IgG1 antibodies. These findings indicate that encapsulated MHSP/TDM is more immunogenic than naked hsp65 DNA, and has great potential to improve vaccine effectiveness against leishmaniasis and tuberculosis.  相似文献   
993.
Coal mining is an activity with a high potential for environmental pollution. Coal has been described as the most significant pollutant of all the fossil fuels, containing a heterogeneous mixture. Many elements present in coal byproducts as well as coal tailings are rich in potentially toxic and genotoxic metals, which ultimately lead to profound changes in cells, tissues, populations, and ecosystems. The purpose of this study was to assess the genotoxic potential of the mineral coal tailings using the land snail Helix aspersa. Animals were divided in three groups, clustered in plexiglass cages: control (animals fed with organic lettuce), coal tailings (animals living in a layer of pyrite tailings and fed with organic lettuce), and mine lettuce (animals fed with lettuce grown in an area located in a deposit of coal tailings). The hemolymph was collected at different exposure times (24 h, 48 h, 72 h, 96 h, 1 week, 2 weeks, 3 weeks, and 1 month) for comet assay analyses. Results showed that the animals of the coal tailings and mine lettuce groups presented higher levels of DNA damage in relation to the control group at all exposure times, but with a peak of DNA damage in 48 h and 96 h. These results demonstrate that the coal pyrite tailings are potentially genotoxic and that H. aspersa has proven to be a sensitive instrument for a better risk assessment of environmental pollution.  相似文献   
994.

Background

The etiology of patellofemoral pain (PFP) is thought to be the result of increased patellofemoral joint (PFJ) load and aberrant lower extremity mechanics, including altered vertical ground reaction forces (VGRF). However, few studies have investigated the association between an increase in pain and VGRF loading rates in the context of PFP. Thus, this study aimed to investigate the immediate effects of PFJ loading on pain and VGRF loading rate, and to see if there is a link between modification of both pain and VGRF loading rate during stair negotiation.

Methods

Thirty-four women with PFP underwent VGRF analysis during stair negotiation under two conditions: with (condition 2) and without (condition 1) being previously submitted to a PFJ loading protocol in order to or not to exacerbate their knee pain, respectively.

Results

The VGRF loading rates were significantly higher in condition 2 (Mean ± standard deviation (SD) = 4.0 ± 0.6 N/s) compared to condition 1 (Mean ± SD = 3.6 ± 0.5 N/s) during stair ascent and during stair descent (Mean ± SD: condition 1 = 6.3 ± 1.1 N/s; condition 2 = 7.0 ± 1.4 N/s). In addition, VGRF loading rates were higher during stair descent compared to stair ascent in both conditions. There were significant correlations between the increase in pain and VGRF loading rate during both tasks.

Conclusion

There seemed to be an important relation between the increase in pain and VGRF loading rates in women with PFP. Based on these findings, interventions aimed at reducing VGRF loading rates are important in the context of PFP.  相似文献   
995.
996.
ABSTRACT

The sexual exploitation of children and adolescents is a frequently underestimated health problem which includes transactional sex (TS), or the practice of sexual activity based on an expected return of benefits, favours and/or support in some form. This qualitative study focuses on age-disparate transactional sex (ATS) in urban favela communities of Rio de Janeiro between adult men (over 18) and girls and adolescents (G/A) (under 18), involving a minimum 5-year age disparity. We have employed social norms theory as a framework to identify the prevailing social norms contributing to or protecting children and adolescents from these relationships. Data collection utilised semi-structured interviews (n?=?30) and ten focus groups with a total of 130 men/boys and women/girls selected through purposive sampling and varying in age from 15 to 65. Overall the findings identify factors, especially the essentialisation of gender, which promote the acceptability of ATS. When ATS surpassed the acceptability threshold, social norms discouraged direct interference. Concluding remarks point to possible strategies for reducing the occurrence of ATS. These must include girls, boys, women and men with community involvement in the deconstruction of social norms involving gender, age and economic consumption.  相似文献   
997.
AIM:To evaluate the overlap of autoimmune hepatitis in hepatitis C virus(HCV)-infected patients with intense interface hepatitis.METHODS:Among 1759 patients with hepatitis C submitted to liver biopsy,92(5.2%) presented intense interface hepatitis.These patients were evaluated regarding the presence of antinuclear antibody(ANA),anti-smooth muscle antibody(SMA) and anti-liver/kidney microsomal antibody(LKM-1),levels of γ-globulin and histological findings related to autoimmune hepatitis(plasma cell infiltrate...  相似文献   
998.
Pituitary tumors are challenging tumors in the sellar region. Surgical approaches to the pituitary have undergone numerous refinements over the last 100 years. The introduction of the endoscope have revolutionized pituitary surgery. The aim of this study is to report the results of a consecutive series of patients undergoing pituitary surgery using a pure endoscopic endonasal approach and to evaluate the efficacy and safety of this procedure. We reviewed the data of 228 consecutive patients who underwent endonasal transsphenoidal adenoma removal over an 10-year period. Pre- and post-operative hormonal status (at least 3 months after surgery) were analyzed and compared with clinical parameters presented by the patients. Tumor removal rate, endocrinological outcomes, and complications were retrospectively assessed in 228 patients with pituitary adenomas who underwent 251 procedures between December 1998 and December 2007. There were 93 nonfunctioning adenomas, 58 growth hormone-secreting, 41 prolactin-secreting, 28 adrenocorticotropin hormone secreting, 7 FSH-LH secreting and 1 thyroid-stimulating hormone-secreting adenomas. Gross total removal was achieved in 79.3% of the cases after a median follow-up of 61.5 months. The remission results for patients with nonfunctioning adenomas was 83% and for functioning adenomas were 76.3% (70.6% for GH hormone-secreting, 85.3% for prolactin hormone-secreting, 71.4% for ACTH hormone-secreting, 85.7% for FSH-LH hormone-secreting and 100% for TSH hormone-secreting), with no recurrence at the time of the last follow-up. Post-operative complications were present in 35 (13.9%) cases. The most frequent complications were temporary and permanent diabetes insipidus (six and two cases, respectively), syndrome of inappropriate antidiuretic hormone secretion (two cases) and CSF leaks (eight cases). There was no death related to the procedure in this series. The endoscopic endonasal approach for resection of pituitary adenomas, provides acceptable results representing a safe alternative procedure to the microscopic approach. This less invasive method, associated with a small number of complications, provides excellent tumor removal rates and represents an important tool for the achievement of good results in the pituitary surgery, mainly for the complete removal of large adenomas.  相似文献   
999.
Sample preparation and DNA extraction protocols for DNA amplification by PCR, which can be applied in human fecal samples for taeniasis diagnosis, are described. DNA extracted from fecal specimens with phenol/chloroform/isoamilic alcohol and DNAzol reagent had to be first purified to generate fragments of 170 pb and 600 pb by HDP2-PCR. This purification step was not necessary with the use of QIAmp DNA stool mini kit. Best DNA extraction results were achieved after eggs disruption with glass beads, either with phenol/chloroform/isoamilic alcohol, DNAzol reagent or QIAmp DNA stool mini kit.  相似文献   
1000.
BACKGROUND: The 13C-methacetin breath test is a non-invasive method to evaluate hepatic microsomal function that allows a quantitative assessment of the functional hepatic mass. AIM: To evaluate the clinical usefulness of the 13C-methacetin breath test in patients with hepatitis C chronic liver disease. PATIENTS AND METHODS: Seventy eight patients with chronic hepatitis C and 13 matched healthy controls were studied. HCV patients were classified as having chronic hepatitis (n = 51), cirrhosis (n = 27), being seven with decompensated disease (presence of ascite, jaundice and/or encephalopathy). HbsAg/HIV co-infected patients, chronic alcohol drinker, having other chronic diseases and those using drugs that could interfere with hepatic cytochrome P450, were excluded. The disease stage and activity in biopsy fragments were determined according the Brazilian Society of Hepatology criteria. Breath test was performed with 75 mg of 13C-methacetin, and the 13CO2 in the expired air was measured through a nondispersive infra red spectrometry. The delta over baseline, and the cumulative recovery of 13CO2 at 40 (13C-methacetin breath test 40 min) and 120 minutes (13C-methacetin breath test 120 min) were calculated. RESULTS: 13C-methacetin breath test parameters correlate only with hepatic staging but not with necroinflammatory (activity) parameters, being the best correlation found between hepatic staging and the 13C-methacetin breath test 120 minutes. The mean values for 13C-methacetin breath test 120 min was significantly reduced in the cirrhotic groups (19.2 +/- 7.1% for compensated and 14.7 +/- 4.0% for decompensated cirrhotics) than in control (29.9 +/- 4.5%) and chronic hepatitis (27.8 +/- 6.1%) groups. The best diagnostic accuracy for the diagnosis of cirrhosis among HCV patients was found for 13C-methacetin breath test 120 min with 81% of sensibility and 77% of specificity. CONCLUSION: 13C-methacetin breath test is correlated with structural changes in HCV-related chronic hepatic diseases and the cumulative recovery at 120 minutes is a sensitive parameter to identify the presence of hepatic cirrhosis in these patients.  相似文献   
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