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721.
Diltiazem is a calcium channel blocker used to treat cardiovascular ailments. In addition, reports suggest that diltiazem induces cell death, which could make it a drug of choice for the treatment of cancer associated with hypertension. The goal of this research was to determine whether diltiazem is capable of inducing apoptosis in prostate cancer cells, either alone or in combination with the proteasome inhibitors, lactacystin and bortezomib (Velcade). Bortezomib is approved for the treatment of multiple myeloma; unfortunately, it has side effects that limit its utility. Presumably these side effects could be decreased by reducing its dose in combination with another drug. We have previously shown that lactacystin induces apoptosis in LNCaP cells; here, we show that this effect was enhanced by diltiazem. Furthermore, in proteasome inhibitor-resistant DU145 cells, diltiazem alone did not induce apoptosis but decreased cytosolic calcium levels and induced mitochondrial fission; likewise, lactacystin did not induce apoptosis but up-regulated the proapoptotic protein Bik. However, increasing concentrations of diltiazem in combination with lactacystin or bortezomib induced apoptosis in a dose-dependent and synergistic manner. The combination of diltiazem and lactacystin also up-regulated the levels of Bik and released Bak from Bcl-xL, indicating the involvement of the Bcl2 family pathway in this apoptosis. In addition, the drug combination up-regulated GRP78, suggesting also the involvement of endoplasmic reticulum stress in the apoptotic response. Thus, our results demonstrate a potential therapeutic advantage of combining a frequently used calcium channel blocker with proteasome inhibitors in the treatment of prostate cancer.  相似文献   
722.
Prostate cancer is the second-leading cause of cancer-associated death among men in the United States. There has been renewed interest in the potential therapeutic benefits of statins for cancer. Simvastatin, a widely used generic drug for preventing cardiovascular events, is well known for its effects on cellular proliferation and inflammation, two key processes that also determine the rate of tumor growth. Although a growing body of evidence suggests that statins have the potential to reduce the risk of many cancers, there are discrepancies over the pro- and anticancer effects of statins. In the current study, we sought to investigate the effects of simvastatin on the Akt pathway in prostate cancer cells with respect to the regulation of various cell functions in vitro and tumor growth in vivo. Time- and dose-dependent effects of simvastatin on LNCaP (androgen-dependent) and PC3 (androgen-independent) cells indicate that treatment with simvastatin at concentrations as low as 25 μM was sufficient to inhibit serum-stimulated Akt activity. Akin to this, treatment with simvastatin significantly inhibited serum-induced cell migration, invasion, colony formation, and proliferation. Simvastatin-mediated effects on colony formation were rescued by adenovirus-mediated expression of constitutively active Akt (myristoylated Akt) in PC3 cell lines. A PC3 xenograft model performed in nude mice exhibited reduced tumor growth with simvastatin treatment associated with decreased Akt activity and reduced prostate-specific antigen (PSA) levels. Our findings demonstrate the therapeutic benefits of simvastatin for prostate cancer and suggest a link between simvastatin, regulation of Akt activity, and PSA expression in prostate tumors.  相似文献   
723.
The detection of the incidents of apnoea of prematurity (AP) in preterm infants is important in the intensive care unit, but this detection is often based on simple threshold techniques, which suffer from poor specificity. Three methods for the automatic detection of AP were designed, tested and evaluated using approximately 2426 h of continuous recording from 54 neonates (μ = 44 h and σ = 7 h). The first method was based on the cumulative sum of the time series of heart rate (HR), respiratory rate (RR) and oxygen saturation (SpO(2)) along with the sum of their Shannon entropy. The performance of this method gave 94.53% sensitivity, 74.72% specificity and 77.84% accuracy. The second method was based on the correlation between the time series of HR, RR and SpO(2), which were used as inputs to an artificial neural network. This gave 81.85% sensitivity, 75.83% specificity and 76.78% accuracy. The third method utilized the derivative of the three time series and yielded a performance of 100% sensitivity, 96.19% specificity and 96.79% accuracy. Although not optimized to work in real time, the latter method has the potential for forming the basis of a real time system for the detection of incidents of AP.  相似文献   
724.

Background

Higher serological prevalence rates of helicobacter pylori (H. pylori) infection have been reported in patients with type 1 diabetes (T1DM) and autoimmune thyroiditis (AT). Patients with T1DM are at increased risk for developing other autoimmune diseases, most commonly AT. It is unknown whether H. pylori infection could explain the high prevalence of thyroid autoantibodies and AT in T1DM. The aim of the current study was to evaluate anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-Tg) autoantibodies in correlation with anti-H. pylori IgG and IgA in young patients with T1DM.

Methods

Anti-H. Pylori IgG, IgA, anti-TPO and anti-Tg antibodies titers were measured in 162 euthyroid patients with T1DM and 80 healthy controls matched for age, sex and socioeconomic status.

Results

Seroprevalence of H. pylori was significantly higher in patients with T1DM than in healthy controls; 79% vs. 51.2%, p < 0.001. Anti H. pylori IgG was positive in 61.1% of patients with T1DM and 30% of controls, p < 0.001, anti H. pylori IgA was positive in 74% of patients with T1DM and 32.5% of controls, p < 0.001. Thyroid autoimmunity was also significantly higher in patients with T1DM than in controls; 56.7% vs. 6.2%, p < 0.001. Anti-TPO was positive in 25.3% of patients with T1DM and 3.7% of controls, p < 0.001, anti-Tg was positive in 47.5% of patients with T1DM and 6.2% of controls, p < 0.001. With simple and multiple regression analysis anti-H. pylori IgG and IgA titers were positively and significantly correlated with Anti-TPO and anti-Tg titers in patients with T1DM.

Conclusion

our results support the idea of a connection between H. pylori infection and the occurrence of anti-TPO, anti-Tg autoantibodies and AT in young patients with T1DM. So, H. pylori infection could be considered as an environmental trigger for development of AT in T1DM. Young patients with T1DM should be screened for H. pylori infection.  相似文献   
725.
Objectives

The present work was conducted to estimate the prevalence of adult Behçet’s disease (BD) in adult Egyptian and to study the clinical pattern and influence of age at-onset and sex on disease phenotype. Also, we investigated the spectrum of presentation and frequencies along the north-to-south gradient of the country.

Patients and method

The population-based, multicenter, cross-sectional study included 1526 adult BD patients from 26 specialized Egyptian rheumatology centers. Demographic, clinical, and therapeutic data are assessed for all patients.

Results

The mean age of patients was 35.7 ± 9.84 years, disease duration 6.58 ± 5.25 years, and age at onset 29.37 ± 8.6 years; 91 were juvenile-onset (JoBD). There were 1102 males and 424 females (M:F 2.6:1). Regarding co-morbidities, 19.92% were diabetic, and 26.05% were hypertensive. The mean body mass index was 27.57 ± 5.24 (43.1% overweight; 25.9% obese). The mean BD current activity form was 4.48 ± 4.28. Regarding the medications use, systemic steroid and colchicine were the most common drugs used (947 (90.2%) and 611 (82.7%), respectively). The overall estimated prevalence of BD in Egypt was 3.6/100,000 population being highest in the two main cities: Alexandria (15.27) and Cairo (8.72). Pathergy test was positive in 43.4%. 90.2% were receiving systemic steroids and 8.3%, biologics. Disease characteristics were comparable between JoBD and adult-onset BD cases. Central nervous system (CNS), deep venous thrombosis (DVT), and gastrointestinal (GIT) involvement were significantly higher in males (p = 0.01, p = 0.001, and p = 0.001 respectively) while joint affection (p = 0.001) and disease activity (p = 0.011) were increased in females.

Conclusions

This study provides current prevalence of BD in Egypt; 3.6/100,000 with no remarkable north-to-south gradient. The sex influences the disease phenotype with the CNS, DVT, and GIT involvement are higher in males, while the joint affection and disease activity were increased in females.

Key Points

The prevalence and phenotype of Behçet’s disease across Egypt is presented in a multicenter nationwide study.

The potential influence of the age at onset and sex on disease phenotype is highlightened.

A review of the literature worldwide is presented allowing comparisons with studies from other nations.

  相似文献   
726.
The possibility of Toxoplasma gondii infection resulting from transplantation of a skin graft and various organs has been investigated. The parasite was detected in very low numbers in all organs examined in wild-type (WT) BALB/c (B/c) mice that received skin grafts from infected interferon gamma knockout (GKO) B/c mice both with and without sulfamethoxazole treatment; all recipient mice survived. In contrast, transplantation of skin grafts from untreated infected WT B/c mice to na?ve GKO B/c mice led to the death of all recipients within 20 days post-transplantation; T. gondii was found to be disseminated in all organs examined. Similar results were obtained after transplantation of skin from untreated and treated GKO B/c mice to na?ve GKO B/c mice, whereas the recipient GKO B/c mice died within 10 days after intraperitoneal transplantation of lung, heart, brain or small intestine from infected untreated GKO B/c mice. These results indicate that skin grafts as well as various organs infected with T. gondii can be sources of infection in immunocompromised hosts. Toxoplasmosis should therefore be taken into consideration during organ transplantation to immunocompromised hosts.  相似文献   
727.
728.
Senile changes in the middle ear joints   总被引:1,自引:0,他引:1  
  相似文献   
729.
Acoustic tumors are one of the common problems that both the otologist and the neurosurgeon face in Egypt. Early diagnosis and choice of surgical approach--whether middle fossa, translabyrinthine, or suboccipital--are discussed after review of forty-one cases of cerebellopontine angle masses we have seen over the last fifteen years. Particular attention is given to the difficulties in the diagnosis and management of acoustic tumors in developing countries. The reliability of the simple, inexpensive radiologic and audiometric tests is compared with that of the sophisticated CT scanning, polytomography, and brain stem evoked response audiometry. The high operative morbidity and mortality rates in this series are analyzed and the value of microsurgery in total extracapsular tumor resection is stressed.  相似文献   
730.
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