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991.
Neoadjuvant endocrine therapy is safe and can be effective in many postmenopausal women with estrogen receptor positive breast cancer. There are limited data available for premenopausal women taking aromatase inhibitors in combination with estrogen suppression. Letrozole, anastrozole, and exemestane have all been shown to be equivalent or superior to tamoxifen in relatively small neoadjuvant trials in postmenopausal women. Tumor factors that appear to have good response are estrogen receptor positivity, characteristics consistent with the so-called Luminal A subtype and lobular carcinomas. Response to neoadjuvant treatment may inform decision making regarding adjuvant treatment, which should include radiotherapy following breast-conserving surgery, or mastectomy, made feasible by neoadjuvant treatment to maintain low local recurrence rates. Chemotherapy may also be required in some cases based on the biological characteristics of the residual tumor and the extent of residual disease.  相似文献   
992.
993.

Background  

Ergosterol peroxide (EP) derived from edible mushroom has been shown to exert anti-tumor activity in several cancer cells. In the present study, anti-angiogenic activity of EP was investigated with the underlying molecular mechanisms in human multiple myeloma U266 cells.  相似文献   
994.

Background  

Curcumin (diferuloylmethane), the yellow pigment in the Asian spice turmeric, is a hydrophobic polyphenol from the rhizome of Curcuma longa. Because of its chemopreventive and chemotherapeutic potential with no discernable side effects, it has become one of the major natural agents being developed for cancer therapy. Accumulating evidence suggests that curcumin induces cell death through activation of apoptotic pathways and inhibition of cell growth and proliferation. The mitotic checkpoint, or spindle assembly checkpoint (SAC), is the major cell cycle control mechanism to delay the onset of anaphase during mitosis. One of the key regulators of the SAC is the anaphase promoting complex/cyclosome (APC/C) which ubiquitinates cyclin B and securin and targets them for proteolysis. Because APC/C not only ensures cell cycle arrest upon spindle disruption but also promotes cell death in response to prolonged mitotic arrest, it has become an attractive drug target in cancer therapy.  相似文献   
995.

Background  

Development of accurate therapeutic approaches to salivary gland neoplasms depends on better understanding of their molecular pathogenesis. Tumour growth is regulated by the balance between proliferation and apoptosis. Few studies have investigated apoptosis in salivary tumours relying almost exclusively on immunohistochemistry or TUNEL assay. Furthermore, there is no information regarding the mRNA expression profile of apoptotic genes in salivary tumors. Our objective was to investigate the quantitative expression of BCL-2 (anti-apoptotic), BAX and Caspase3 (pro-apoptotic genes) mRNAs in salivary gland neoplasms and examine the association of these data with tumour size, proliferative activity and p53 staining (parameters associated with a poor prognosis of salivary tumours patients).  相似文献   
996.
997.
The principle of symmetry-asymmetry is widely presented in the structural and functional organization of the nonliving and living nature. One of the most complex manifestations of this principle is the left-right asymmetry of the human brain. The present review summarizes previous and contemporary literary data regarding the role of brain asymmetry in neuroimmunomodulation. Some handedness-related peculiarities are outlined additionally. Brain asymmetry is considered to be imprinted in the formation and regulation of the individual’s responses and relationships at an immunological level with the external and internal environment. The assumptions that the hemispheres modulate immune response in an asymmetric manner have been confirmed in experiments on animals. Some authors assume that the right hemisphere plays an indirect role in neuroimmunomodulation, controlling and suppressing the left hemispheric inductive signals.  相似文献   
998.
The aim of this study was to determine influence of selected lifestyle factors on kidney cancer. The study brings data from two centres of international multicentric hospital-based analytical observational case-control studies. Data were obtained from a group of 300 patients newly diagnosed with kidney cancer (ICD-O-2 code C64) and 335 controls from two centres in the Czech Republic. Results showed that smoking increased OR to 1.09 (95% CI 0.77–1.55) and 1.06 (95% CI 0.73–1.52), but the results were not statistically significant. Obesity (BMI⩾30) created adjusted OR 1.71 (95% CI 1.11–2.66) and 1.44 (95% CI 0.91–2.28), showing a minor, statistically insignificant, effect of obesity on the development of kidney cancer. For hypertension, adjusted OR was 1.73 (95% CI 1.25–2.40), suggesting a minor to moderate effect of hypertension on kidney cancer. The analysis results showed a positive association between hereditary predisposition and the development of kidney cancer with an OR of 1.97 (95% CI 1.41–2.76) and 1.97 (95% CI 1.40–2.77) depending on the model of adjustment. The reasons for the high incidence of kidney cancer are not fully understood. Genetic polymorphisms, together with other lifestyle and environmental factors, are likely to contribute to various rates of kidney cancer incidence throughout the world.  相似文献   
999.
Quality assurance becomes an increasingly important part of clinical medicine and of the field of endoscopy. Endoscopic sphincterotomy is associated with a fairly high complication rate. We aimed to assess our quality of sphincterotomy for benchmarking by using a prospective electronic database registry, and to identify potential risk factors for post-interventional complications. Over 2 years, 471 sphincterotomies were performed in a single tertiary referral centre. Patient- and procedure-related variables were prospectively recorded with the support of a multi-centre international sphincterotomy registry. Multivariate analysis was performed. The overall post-interventional complication rate was 9.3%. Pancreatitis happened in 5.5%, bleeding in 2.1%, perforation in 1.3%, and cholangitis in 0.4%. In the multivariate analysis following variables remained highly significant and predictive for complications: ‘papilla only in lateral view’ (p=0.001), antiplatelet therapy (p=0.024), and opacification with contrast up to the pancreatic tail (p=0.001). The primary success rate of sphincterotomy was 95.1%. The rate of post-interventional pancreatitis did not differ significantly regardless of the presence of prophylactic pancreatic stent (p=0.56). The outcome of sphincterotomy in our centre matches with literature data. The extent of pancreatic duct opacification has an influence on the pancreatitis rate. Prevention of pancreatitis by inserting pancreatic stents is not confirmed.  相似文献   
1000.
The purpose of this study was to investigate the relationship between weight status and recreational drug use in Korean adolescents. A total of 72,399 adolescent students (38,152 boys and 34,247 girls) from the middle first to high third grade participated in the 5th Korea Youth Risk Behaviour Web-based Survey (KYRBWS-V) project in 2009. They were assessed for body mass index (BMI) and recreational drug abuse. The associations between BMI and recreational drug use were examined using multivariable logistic regression analysis after adjusting for the covariate variables of age, smoking frequency and cigarette consumption, frequency of alcohol consumption and severe alcohol intoxication, amount of alcohol consumed, parents’ education level, economic status, sedentary activities during the week, mental stress, sleep duration, frequency of vigorous and moderate physical activities, and muscular strength exercises during the week. For boys, the odds ratio (OR) (95% confidence interval [CI]) between overweight and drug use were 0.990 (0.723–1.356; p = 0.950) for almost none, 0.939 (0.521–1.693; p = 0.834) for past use, and 0.791 (0.385–1.624; p = 0.523) for present use. The OR (95% CI) between obesity and drug use was 0.731(0.508–1.052; p = 0.091) for almost none, 0.755 (0.389–1.465; p = 0.407) for past use, and 0.701 (0.314–1.565; p = 0.386) for present use. For girls, the OR (95% CI) between overweight and drug use was 1.112 (0.702–1.763; p = 0.650) for almost none, 1.103 (0.464–2.619; p = 0.825) for past use, and 0.927 (0.267–3.218; p = 0.905) for present use. The OR (95% CI) between obesity and drug abuse was 0.594 (0.261–1.352; p = 0.215) for almost none, 1.318 (0.462–3.764; p = 606) for past use, and <0.001(<0.001–<0.001; p = 0.998) for present use. We concluded that recreational drug use had no correlation with overweight and obesity in Korean adolescents.  相似文献   
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