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991.
992.

Background.

Reduced estimated glomerular filtration rate (eGFR) has been associated with increased venous thromboembolism (VTE) risk in the general population. VTE incidence significantly increases in cancer patients, especially those undergoing chemotherapy. Despite the evidence that a substantial number of cancer patients have unrecognized renal impairment, as indicated by reduced eGFR in the presence of serum creatinine levels within the reference value, chemotherapy dosage is routinely adjusted for serum creatinine values. Among chemotherapies, platinum-based regimens are associated with the highest rates of VTE. A cohort study was designed to assess the value of pretreatment eGFR in the risk prediction of a first VTE episode in cancer outpatients without previous history of VTE who were scheduled for platinum-based chemotherapy.

Methods.

Serum creatinine and eGFR were evaluated before the start of standard platinum-based chemotherapy in a cohort of 322 consecutive patients with primary or relapsing/recurrent solid cancers, representative of a general practice population.

Results.

Patients who experienced a first VTE episode in the course of chemotherapy had lower mean eGFR values compared with patients who remained VTE free. Multivariate Cox analysis demonstrated that eGFR had an independent value for risk prediction of a first VTE episode during treatment, with a 3.15 hazard ratio. Indeed, 14% of patients with reduced eGFR had VTE over 1-year follow-up compared with 6% of patients with normal eGFR values.

Conclusion.

The results suggest that reductions in eGFR, even in the presence of normal serum creatinine, are associated with an increased VTE risk in cancer outpatients undergoing platinum-based chemotherapy regimens. Determining eGFR before chemotherapy could represent a simple predictor of VTE, at no additional cost to health care systems.  相似文献   
993.

Background.

The evidence supporting the use of trastuzumab (T) in a metastatic setting comes from studies that included (almost) only patients who never received prior T. We investigated the effectiveness of T as first-line therapy for metastatic breast cancer (mBC) in women previously treated with T in the adjuvant setting.

Materials and Methods.

By using record linkage of five administrative health care databases of Lombardy, Italy, we identified 2,046 women treated with T for early breast cancer (eBC) in 2006–2009, 96 of whom developed a metastasis and were retreated with T in first-line treatment for mBC (treatment group). We compared the overall survival (OS) of these women with that of 197 women treated with T in first-line treatment for mBC, who were treated with therapies other than T for early disease (control group). We computed Kaplan-Meier 2-year OS and used a proportional hazard model to estimate the multivariate hazard ratio (HR) of death in the intervention group compared with the control group, adjusted by age, use of endocrine therapy, and site of metastasis.

Results.

Two-year OS was 60.0% in the treatment group and 59.5% in the control group. The adjusted HR of death in the treatment group compared with the control group was 0.79 (95% confidence interval, 0.50–1.26).

Conclusion.

Our data provide convincing evidence that the outcome of women receiving first-line T treatment for mBC after T failure in the adjuvant setting is comparable to that of women not receiving T for eBC. These data are of specific interest, given the unavailability of data from randomized clinical trials.  相似文献   
994.

Introduction

intra-abdominal candidiasis (IAC) may include Candida involvement of peritoneum or intra-abdominal abscess and is burdened by high morbidity and mortality rates in surgical patients. Unfortunately, international guidelines do not specifically address this particular clinical setting due to heterogeneity of definitions and scant direct evidence. In order to cover this unmet clinical need, the Italian Society of Intensive Care and the International Society of Chemotherapy endorsed a project aimed at producing practice recommendations for the management of immune-competent adult patients with IAC.

Methods

A multidisciplinary expert panel of 22 members (surgeons, infectious disease and intensive care physicians) was convened and assisted by a methodologist between April 2012 and May 2013. Evidence supporting each statement was graded according to the European Society of Clinical Microbiology and Infection Diseases (ESCMID) grading system.

Results

Only a few of the numerous recommendations can be summarized in the Abstract. Direct microscopy examination for yeast detection from purulent and necrotic intra-abdominal specimens during surgery or by percutaneous aspiration is recommended in all patients with nonappendicular abdominal infections including secondary and tertiary peritonitis. Samples obtained from drainage tubes are not valuable except for evaluation of colonization. Prophylactic usage of fluconazole should be adopted in patients with recent abdominal surgery and recurrent gastrointestinal perforation or anastomotic leakage. Empirical antifungal treatment with echinocandins or lipid formulations of amphotericin B should be strongly considered in critically ill patients or those with previous exposure to azoles and suspected intra-abdominal infection with at least one specific risk factor for Candida infection. In patients with nonspecific risk factors, a positive mannan/antimannan or (1→3)-β-d-glucan (BDG) or polymerase chain reaction (PCR) test result should be present to start empirical therapy. Fluconazole can be adopted for the empirical and targeted therapy of non-critically ill patients without previous exposure to azoles unless they are known to be colonized with a Candida strain with reduced susceptibility to azoles. Treatment can be simplified by stepping down to an azole (fluconazole or voriconazole) after at least 5–7 days of treatment with echinocandins or lipid formulations of amphotericin B, if the species is susceptible and the patient has clinically improved.

Conclusions

Specific recommendations were elaborated on IAC management based on the best direct and indirect evidence and on the expertise of a multinational panel.  相似文献   
995.
Hypoxia-inducible factor-1α (HIF-1α) is frequently overexpressed and activated in many cancer types. However, its regulation and function in thyroid carcinomas are only partially known. Aim of our study was to demonstrate that adaptation to the hypoxic micro-environment by human papillary thyroid carcinoma (PTC) cells, in the absence of leukocyte infiltrate, induces a “molecular inflammation” process characterized by the expression of a large set of genes normally involved in inflammation. To address this, tumor, peritumor or normal host tissue from eleven human PTC surgical samples, were separated by laser capture microdissection (LCMD) and studied by real-time quantitative PCR and Western blot. In such condition, we observed an increased expression and activation of HIF-1α, NF-kB and pro-inflammatory genes only in tumor tissues. Importantly, an anti-inflammatory gene such as SOCS-1 was markedly down-regulated in tumor tissue compared to surrounding normal host tissue. Similar results were found in fine-needle aspiration biopsy (FNAB)-derived specimens from PTC and in hypoxic human papillary thyroid tumor cell line, BCPAP. Moreover, we also detected an elevated expression of metalloproteinase-9 (MMP9) both in solid tumor and in hypoxic-treated BCPAP cells. Our findings reveal that, in human PTC tumor, hypoxic conditions are accompanied by up-regulation of pro-inflammatory genes, down-regulation of anti-inflammatory genes and increased expression of MMP9. We propose that a better understanding of the pro- and anti-inflammatory pathways involved in the “molecular inflammation” process even in the absence of leukocyte, may help to clarify progression toward malignancy and may prove useful for new anti-tumor strategy.  相似文献   
996.
997.
This sheep study was designed to make a comparative evaluation of two external fixation pin types each with and without hydroxyapatite (HA) coating. The two pins had different taper, pitch, and self drilling capabilities. Twenty Orthofix standard, self-tapping pins (group A), 20 Orthofix HA-coated, self-tapping pins (group B), 20 X-caliber, self-drilling, self-tapping pins (group C), and 20 X-caliber HA-coated, self-drilling, self-tapping pins (group D) were selected. Four pins were implanted in the right femurs of 20 adult sheep that were euthanized at 6 weeks. Mean pin insertion torque was 2745 +/- 822 Nmm in group A, 2726 +/- 784 Nmm in group B, 2818 +/- 552 Nmm in group C, and 2657 +/- 732 Nmm in group D (ns). Mean pin extraction torque was 1567 +/- 541 Nmm in group A, 2524 +/- 838 Nmm in group B, 1650 +/- 650 Nmm in group C, and 2517 +/- 726 Nmm in group D. HA-coated pins (group B and D) had a significantly greater mean pin extraction torque compared to similar uncoated pins (group A and C) (p < 0.0005). Histological analysis showed good osteointegration of the two coated pin types. This study shows that HA-coating is more important for optimal pin fixation than the particular combination of design parameters used in each pin type.  相似文献   
998.
999.
Atypical adenomatous hyperplasia (AAH) is considered the preinvasive lesion of pulmonary adenocarcinoma, and mutations of EGFR, HER2, and K-ras are involved in the early stage of lung adenocarcinoma carcinogenesis, also predicting clinical response to anti-EGFR small molecule inhibitors. We analyzed 18 cases of primary lung adenocarcinoma with concomitant AAH foci from 13 patients for mutations of EGFR (exons 18-21), HER2 (exons 19-20), and K-ras (exon 2) by direct sequencing polymerase chain reaction. Among mutated cases, concordant mutations of EGFR or K-ras in adenocarcinoma and related AAH were observed in 5 (63%) of 8 cases. In particular, 3 of 4 adenocarcinomas with EGFR mutations (all L858R point mutations in women, never or former smokers) had a concomitant and identical mutation in AAH, and 2 of 4 adenocarcinomas with K-ras mutations (both at codon 12 in women, a never and a current smoker) showed the same mutation in concomitant AAH. All cases were wild-type for HER2. Mutations of EGFR and K-ras genes represent an early event in lung adenocarcinomagenesis, and AAH convincingly seems to be a precursor lesion in a subset of cases of adenocarcinoma.  相似文献   
1000.
An antimetastatic role for decorin in breast cancer   总被引:1,自引:0,他引:1  
Decorin, a member of the small leucine-rich proteoglycan gene family, down-regulates members of the ErbB receptor tyrosine kinase family and attenuates their signaling, leading to growth inhibition. We investigated the effects of decorin on the growth of ErbB2-overexpressing mammary carcinoma cells in comparison with AG879, an established ErbB2 kinase inhibitor. Cell proliferation and anchorage-independent growth assays showed that decorin was a potent inhibitor of breast cancer cell growth and a pro-apoptotic agent. When decorin and AG879 were used in combination, the inhibitory effect was synergistic in proliferation assays but only additive in both colony formation and apoptosis assays. Active recombinant human decorin protein core, AG879, or a combination of both was administered systemically to mice bearing orthotopic mammary carcinoma xenografts. Primary tumor growth and metabolism were reduced by approximately 50% by both decorin and AG879. However, no synergism was observed in vivo. Decorin specifically targeted the tumor cells and caused a significant reduction of ErbB2 levels in the tumor xenografts. Most importantly, systemic delivery of decorin prevented metastatic spreading to the lungs, as detected by novel species-specific DNA detection and quantitative assays. In contrast, AG879 failed to have any effect. Our data support a role for decorin as a powerful and effective therapeutic agent against breast cancer due to its inhibition of both primary tumor growth and metastatic spreading.  相似文献   
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