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101.
Isospora belli diarrhea is usually associated with immunosuppression. This parasite has rarely been reported as a cause of travelers' diarrhea in immunocompetent patients. We present a clinical case of travelers' diarrhea due to I belli in a patient with transient lymphopenia secondary to dengue infection.  相似文献   
102.
CD24, a mucin-like adhesion molecule that enhances the metastatic potential of malignant cells, has been suggested to be a marker of poor prognosis in breast carcinomas. The tumor-initiating potential of CD44posCD24pos cell populations has been recently recognized and, accordingly, distant metastases are largely composed of CD24-positive cells in breast cancer patients refractory to treatment. Therefore, new therapeutic strategies aimed at down-regulating CD24 may negatively regulate the dissemination of tumor cells and formation of metastasis. Here, we reveal that suppression of CD24 protein expression is a crucial event in the molecular mechanisms underlying the growth-inhibitory effects of the anti-diabetic drug metformin in MDA-MB-468 triple-negative (basal-like) breast cancer cells. First, we confirmed that, among the different molecular classes of breast cancer, basal-like breast cancer cells were significantly more sensitive to the growth-inhibitory effects of metformin. Second, we observed a positive correlation between the growth inhibitory activity of metformin and the relative enrichment in cells bearing the CD44posCD24pos immunophenotype. Third, high-content indirect immunofluorescence imaging assays revealed that CD24 protein levels were drastically decreased in the presence of growth-inhibitory concentrations of metformin. Fourth, to preliminary assess the clinical relevance of metformin's anti-CD24 effects we took advantage of the recently developed ROCK online interface (http://rock.icr.ac.uk/), a publicly accessible portal that allows rapid integration of breast cancer functional and molecular profiling datasets. When we evaluated the impact of CD24 expression on distant metastasis-free survival (DMFS) in microarray gene expression breast cancer datasets, Kaplan-Meier survival analyses and log-rank tests comparing DMSF for CD24-high and CD24-low breast carcinomas revealed that patients with CD24-high tumors tended to have a shorter DMFS. These findings, altogether, suggest that the ability of metformin to suppress the oncogene, metastasis promoter and breast cancer stem cell marker CD24 may open a novel molecular avenue in the therapeutic management of highly-metastastic subgroups of triple-negative (basal-like) breast cancers naturally enriched with CD44posCD24pos tumor-initiating cell populations.  相似文献   
103.
Osteoclast inhibitory lectin (OCIL) is a newly recognized inhibitor of mouse and human osteoclast differentiation whose cellular expression is similar to that of receptor activator of nuclear factor kappaB (RANKL). The main objective of the present work was to elucidate whether naturally occurring single-nucleotide polymorphisms (SNPs) in this gene could be associated with bone mass in postmenopausal women. To that end, we studied the association of bone mineral density (BMD) measured by dual-energy X-ray absorptiometry with two nonsynonymous SNPs in the OCIL gene resulting in Asn19Lys and Leu23Val substitutions in a population of 500 postmenopausal Spanish women. A weak association was detected for Asn19Lys SNP with femoral neck (FN) BMD and lumbar spine (LS) BMD in the whole population. When the population was stratified by age, however, the association was strong in older women (> or =53 years). Thus, in this group of participants, women with CG/GG genotype displayed reductions of 5.6% and 6.7% in FN BMD and LS BMD adjusted by age and body mass index (BMI), respectively, compared to women with CC genotype. The Asn19Lys SNP alleles explained about 7% of BMD variance in older women but only 1.7-3.9% in the whole population in regression models including age and BMI. In conclusion, women with a lysine (GG genotype) at position 19 of the OCIL protein displayed lower BMD at femoral neck and at lumbar spine sites than women having an asparagine residue. Since the OCIL protein inhibits osteoclast differentiation, this amino acid substitution could have consequences for OCIL functionality.  相似文献   
104.
BACKGROUND: Ectopic lymphoid neogenesis (LN) occurs in rheumatoid synovium, where it is thought to drive local antigen-dependent B cell development and autoantibody production. This process involves the expression of specific homing chemokines and the development of high endothelial venules (HEV). OBJECTIVE: To investigate whether these mechanisms occur in psoriatic arthritis (PsA) synovium, where autoantibodies have not been described and the organisation and function of B cells is not clear, and to analyse their clinical correlates. METHODS: Arthroscopic synovial biopsy specimens from patients with PsA before and after tumour necrosis factor alpha blockade were characterised by immunohistochemical analysis for T/B cell segregation, peripheral lymph node addressin (PNAd)-positive HEV, and the expression of CXCL13, CCL21 and CXCL12 chemokines in relation to the size of lymphoid aggregates. RESULTS: Lymphoid aggregates of variable sizes were observed in 25 of 27 PsA synovial tissues. T/B cell segregation was often observed, and was correlated with the size of lymphoid aggregates. A close relationship between the presence of large and highly organised aggregates, the development of PNAd+ HEV, and the expression of CXCL13 and CCL21 was found. Large organised aggregates with all LN features were found in 13 of 27 tissues. LN in PsA synovitis was not related to the duration, pattern or severity of the disease. The synovial LN pattern remained stable over time in persistent synovitis, but a complete response to treatment was associated with a regression of the LN features. CONCLUSIONS: LN occurs frequently in inflamed PsA synovial tissues. Highly organised follicles display the characteristic features of PNAd+ HEV and CXCL13 and CCL21 expression, demonstrating that the microanatomical bases for germinal centre formation are present in PsA. The regression of LN on effective treatment indicates that the pathogenic and clinical relevance of these structures in PsA merits further investigation.  相似文献   
105.
Background

Melatonin is an indole hormone secreted primarily by the pineal gland that showing anti-oxidant, anti-inflammatory and anti-apoptotic capacity. It can play an important role in the pathophysiological mechanisms of various diseases. In this regard, different studies have shown that there is a relationship between Melatonin and Multiple Sclerosis (MS). MS is a chronic immune-mediated disease of the Central Nervous System.

Aim

The objective of this review was to evaluate the mechanisms of action of melatonin on oxidative stress, inflammation and intestinal dysbiosis caused by MS, as well as its interaction with different hormones and factors that can influence the pathophysiology of the disease.

Results

Melatonin causes a significant increase in the levels of catalase, superoxide dismutase, glutathione peroxidase, glutathione and can counteract and inhibit the effects of the NLRP3 inflammasome, which would also be beneficial during SARS-CoV-2 infection. In addition, melatonin increases antimicrobial peptides, especially Reg3β, which could be useful in controlling the microbiota.

Conclusion

Melatonin could exert a beneficial effect in people suffering from MS, running as a promising candidate for the treatment of this disease. However, more research in human is needed to help understand the possible interaction between melatonin and certain sex hormones, such as estrogens, to know the potential therapeutic efficacy in both men and women.

  相似文献   
106.

Background

According to some studies, almost 40% of depressive patients – half of them previously undetected – are diagnosed of bipolar II disorder when systematically assessed for hypomania. Thus, instruments for bipolar disorder screening are needed. The Mood Disorder Questionnaire (MDQ) is a self-reported questionnaire validated in Spanish in stable patients with a previously known diagnosis. The purpose of this study is to evaluate in the daily clinical practice the usefulness of the Spanish version of the MDQ in depressive patients.

Methods

Patients (n = 87) meeting DSM-IV-TR criteria for a major depressive episode, not previously known as bipolar were included. The affective module of the Structured Clinical Interview (SCID) was used as gold standard.

Results

MDQ screened 24.1% of depressive patients as bipolar, vs. 12.6% according to SCID. For a cut-off point score of 7 positive answers, sensitivity was 72.7% (95% CI = 63.3 – 82.1) and specificity 82.9% (95% CI = 74.9–90.9). Likelihood ratio of positive and negative tests were 4,252 y 0,329 respectively.

Limitations

The small sample size reduced the power of the study to 62%.

Conclusion

Sensitivity and specificity of the MDQ were high for screening bipolar disorder in patients with major depression, and similar to the figures obtained in stable patients. This study confirms that MDQ is a useful instrument in the daily clinical assessment of depressive patients.
  相似文献   
107.
108.

Background

Routine histologic analysis of lymph nodes (LN) for detecting disseminated bladder urothelial carcinoma (BUC) lacks sensitivity.

Objective

To identify and test potential mRNA markers of BUC dissemination in LN that has been missed by histological analysis, and to compare the performance of selected markers with patients’ clinical outcome.

Design, setting, and participants

Microarray data and a literature search were used to identify potential markers expressed in BUC but absent in LN. Five genes were finally selected to be studied by quantitative real-time RT-PCR (qRT-PCR) in 181 and 29 LN from 102 BUC patients and 29 controls, respectively, collected from 2002 to 2004 (median follow-up of 35 mo).

Measurements

The three most expressed genes plus two additional markers selected from the literature were finally evaluated by qRT-PCR. Gene expression values were statistically compared with histologic results and clinical outcome.

Results and limitations

A discriminant analysis showed that the combination of FXYD3 and KRT20 genes yielded a 100% sensitivity and specificity differentiating LN with BUC dissemination from controls. Combined, the expression of both genes allowed the identification of urothelial cells in LN in 20.5% of patients with previous histologically negative LN. These patients did not have a significantly worse survival than those who were negative by qRT-PCR.

Conclusions

Using molecular markers it was possible to improve the sensitivity of LN histologic analysis. However, since 20.5% of patients that reclassified as positive by qRT-PCR did not have a significantly worse survival, we assume lymphadenectomy was important to remove residual disease.  相似文献   
109.
ObjectiveIn the year 2006 the Hospital Complex of Jaén began a new model of attention for consultation of knee osteoarthritis (CMAR), to offer quality treatment to the patient based on clinical practice guidelines. The objective of this study was to analyse the efficiency of the unit, in terms of delaying the time until a knee prostheses is needed.Patients and methodsAn analysis of a retrospective cohort of patients seen at the CMAR was made, with a minimum available data set, and a Kaplan Meier analysis carried out in order to evaluate the time until the referral of the patient to surgery, as well as a Cox regression analysis in order to study the factors related with the time until the referral.Results224 patients were included, with mean age of 65.7 years (95% CI 64 to 67), 67.9% women. 48.2% had a stage III affection (Kellgren-Lawrence), 27.5% stage 2, 15.3% stage 4, and 9% stage 1. 90.2% (202) received treatment with viscosupplementation (Hialuronic acid NASHA). Single joint affection (P<.0001; OR 0,267, 95% CI 0.130 to 0,549), a higher degree of osteoarthritis (P=.048; OR 0,410, 95% CI 0.169 to 0,992), and lower intensity of pain (P<.0001; OR 1,091, 95% CI 1.044 to 1,141), were the factors related with shorter time until surgery. Treatment with viscosupplementation increased the time until surgery in all patients.ConclusionsFactors like a lower age of the patient and the involvement of a single joint influenced the referral of the patient to surgery. The administration of viscosupplementation, delayed the time until the patient was finally referred to surgery.  相似文献   
110.
For drugs such as anticancer agents every effort should be made to minimize inter-patient variability in drug exposure in order to maximize the benefit while maintaining an acceptable risk level of serious adverse effects. Anticancer drugs generally have a preferential route of elimination, either in urine or in bile and feces. In consequence, dose individualization to renal and liver function permits excessive toxicity to be avoided and expected therapeutic benefit to be achieved. However, less is known about the most appropriate starting doses of antineoplastic agents in these individuals. In this review, we discuss trials that have specifically assessed new targeted agents dosing strategies (mainly monoclonal antibodies and tyrosine kinase inhibitors) in the setting of overt biochemical renal and liver dysfunction and we proportionate recommendations and practical guidelines for dose individualization.  相似文献   
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