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51.
Objectives: The purpose of this study was to describe the role of hepatitis B virus (HBV) and hepatitis C virus (HCV) in the etiology of hepatocellular carcinoma (HCC). Methods: During a 4-year period from January 1995 to December 1998, blood samples and questionnaire data were obtained from 333 incident cases of HCC from Athens, Greece, as well as from patients in two control groups, also from Athens. Controls were 272 metastatic liver cancer (MLC) patients and 360 patients hospitalized for injuries or eye, ear, nose or throat conditions. Coded sera were tested for hepatitis B surface antigen (HBsAg) and antibodies to hepatitis C virus (anti-HCV) by third-generation enzyme immunoassays. Results: The odds ratios (with 95% confidence intervals) in logistic regression modeling comparing the HCC cases to the combined control series were 48.8 (30.5–78.3) for the presence of HBsAg and 23.2 (11.4–47.3) for the presence of anti-HCV. The odds ratio for concurrent infection with HBV and HCV was 46.2 (9.9–216.6) compared to infection with neither virus. Conclusions: Although HBV and HCV are both important causes of HCC in this study population the data do not suggest, neither do they conclusively refute, a super-additive interaction between the two infections in the development of this malignancy. In this population, 58% of HCC cases can be attributed to HBV, 12% to HCV, and 3% to dual infection with these viruses.  相似文献   
52.
Role of TGF-beta in cancer and the potential for therapy and prevention   总被引:7,自引:0,他引:7  
Transforming growth factor (TGF)-beta is a naturally occurring potent inhibitor of cell growth. TGF-beta binds first to a Type II (TGFBR2), then a Type I receptor (TGFBR1). TGFBR1 activation results in the phosphorylation of intracellular messengers, the SMADs. Unrestricted cell growth due to decreased growth inhibitory activity is a paramount feature of a defect in TGF-beta function. There is growing evidence that common variants of the TGF-beta pathway ligand and receptors that alter TGF-beta signaling modify cancer risk. Approximately 14% of the general population carry TGFBR1*6A, a variant of the TGFBR1 gene that results in decreased TGF-beta-mediated growth inhibition. Recent studies show that overall cancer risk is increased by 70 and 19% among TGFBR1*6A homozygotes and heterozygotes, respectively. This suggests that TGFBR1*6A may contribute to the development of a large proportion of common forms of cancer and may become a target for cancer chemoprevention. While decreased TGF-beta signaling increases cancer risk, TGF-beta secretion and activated TGF-beta signaling enhances the aggressiveness of several types of tumors. The activated TGF-beta signaling pathway is emerging as an attractive target in cancer and the authors predict that assessment of functionally relevant variants of this pathway will lead to the identification of individuals with a higher cancer risk and account for some forms of familial cancer susceptibility. In addition, it is predicted that inhibitors of the TGF-beta signaling pathway will find their way into cancer clinical trials, leading to delays in tumor progression and improvements in overall survival.  相似文献   
53.
O'Brien BE  Kaklamani VG  Benson AB 《Clinical colorectal cancer》2005,4(6):375-81; discussion 382-3
Cancer treatment-induced diarrhea affects a high percentage of patients with cancer that receive chemotherapy or radiation treatment. Widely used criteria for measuring treatment-induced diarrhea, such as the National Cancer Institute Common Toxicity Criteria, do not account for important characteristics of treatment-induced diarrhea. These characteristics include the assessment of the duration of the diarrhea, coexisting symptoms, abdominal cramping, or the presence of nocturnal diarrhea. Until recently, there were no universally accepted guidelines for the management of diarrhea. An expert panel developed guidelines with recommendations regarding assessment of the patient and treatment. These guidelines stress the importance of a thorough assessment of the patient, and treatment based upon severity of symptoms. By employing these guidelines, the aggressive management of diarrhea may impact the overall morbidity of this symptom. Education regarding the importance of diarrhea is essential. Patients who are informed will better understand their role in managing this side effect and when to contact their health care provider with emergent symptoms. Early recognition and management of diarrhea will be essential to improve control of diarrhea, and in turn will positively impact patients' quality of life.  相似文献   
54.
TGFBR1*6A may contribute to hereditary colorectal cancer.   总被引:14,自引:0,他引:14  
PURPOSE: TGFBR16A is a tumor susceptibility gene that increases breast, colon, and ovarian cancer risk. Fourteen percent of the general population carries TGFBR16A, and TGFBR16A homozygotes have a greater than 100% increased colon cancer risk compared with noncarriers. Low-penetrance genes such as TGFBR16A may account for a sizable proportion of familial colorectal cancer occurrences. To test this hypothesis, we determined whether TGFBR16A contributes to a proportion of mismatch repair (MMR) gene mutation-negative hereditary nonpolyposis colorectal cancer (HNPCC) patients. PATIENTS AND METHODS: A case-case study was performed of 208 index patients with HNPCC meeting the Amsterdam criteria. Patients were examined for mutations and genomic rearrangements in the MLH1, MSH2, and MSH6 genes and genotyped for TGFBR16A. Tumor microsatellite instability status was available for 95 patients. RESULTS: A total of 144 patients (69.2%) carried a deleterious mutation and were classified as positive for MMR gene mutation; 64 patients (30.8%) had no evidence of mutations and were classified as MMR negative. TGFBR16A allelic frequency was significantly higher among MMR-negative patients (0.195) than among MMR-positive patients (0.104; P = .011). The proportion of TGFBR16A homozygotes was nine-fold higher among MMR-negative (6.3%) than among MMR-positive patients (0.7%; P = .032). The highest TGFBR16A allelic frequency was found among MMR-negative patients with tumors exhibiting no microsatellite instability (0.211), and the lowest frequency was found among MMR-positive patients with tumors exhibiting microsatellite instability (0.121); the difference was not statistically significant (P = .17). CONCLUSION: TGFBR16A may be causally responsible for a proportion of HNPCC occurrences.  相似文献   
55.
One rationale for the development of new treatment strategies for advanced breast cancer is to provide targeted antineoplastic therapy, while at the same time improving the quality of life of patients. One such drug, capecitabine (Xeloda), is an oral fluoropyrimidine 5-fluorouracil carbamate. Capecitabine is converted to 5-fluorouracil primarily in cancer tissue and it has been demonstrated to combine ease of administration, a manageable toxicity profile and potent antineoplastic activity. Capecitabine is widely used in metastatic breast cancer and offers symptom palliation and in combination with docetaxel (Taxotere) improved survival compared with docetaxel alone. Its toxicity profile includes hand-foot syndrome and stomatitis and diarrhea, whereas its hematologic side effects are mild. Capecitabine has been evaluated as a single agent in women with advanced breast cancer where it offers an overall response rate of 20-30%. Capecitabine is synergistic with other chemotherapeutic agents, such as the taxanes, where it increases the response rate to over 40%. This review will place the available data on the use of capecitabine in metastatic breast cancer as a single agent or as part of a combination regime in context.  相似文献   
56.
PURPOSE: To evaluate and quantify the association between consumption of specific food groups/macronutrients and concentrations of serum insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3). SUBJECTS AND METHODS: Data from a comprehensive food-frequency questionnaire administered to 115 healthy subjects were used to study cross-sectionally the relationship between nutritional factors and circulating IGF-1 and IGFBP-3 concentrations. Adjustment for the effect of total energy intake and a series of epidemiologic parameters (age, sex, height, body mass index, smoking, alcohol consumption, and coffee drinking) was implemented through multivariate linear regression. RESULTS: We observed that serum levels of IGF-1 are positively associated with consumption of red meats, fats, and oils. In addition, serum levels of IGF-1 are independently and positively associated with energy intake from lipids and negatively associated with energy intake from carbohydrates. Finally, serum levels of IGFBP-3 are independently and negatively associated with energy intake from saturated fat. CONCLUSION: Serum IGF-1 and/or IGFBP-3 concentrations are associated with red meat, carbohydrate intake, and fat intake and, thus, may mediate the effect of these dietary factors on the pathogenesis of several disease states. Additional studies are needed to further quantify these associations and elucidate the underlying mechanisms.  相似文献   
57.
PURPOSE: Insulin-like growth factor (IGF-1) and its major binding protein (IGF-BP3) have recently been implicated in the pathogenesis of several malignancies. However, anthropometric and lifestyle predictors of these hormones have not been elucidated. Here we report the results of a cross-sectional study. SUBJECTS AND METHODS: This cross-sectional study examines the relationship of a series of epidemiologic parameters (age, sex, height, body mass index, smoking, alcohol consumption, and coffee drinking) with IGF-1 and IGF-BP3 in a sample of 130 healthy adults. RESULTS: We observed that serum levels of IGF-1 are higher, whereas levels of IGF-BP3 are lower, in men than in women. In addition, serum levels of IGF-1 are independently and negatively associated with age and positively associated with pack-year history of smoking. Finally, serum levels of IGF-BP3 are independently and negatively associated with the number of cigarettes smoked per day or pack-year history of smoking. CONCLUSION: Age, sex, and smoking are independent predictors of IGF-1 and/or IGF-BP3. The influence of these epidemiologic variables on the pathogenesis of disease states associated with IGF-1 and IGF-BP3 warrants further exploration.  相似文献   
58.
Understanding of the genetic basis of autoimmune diseases is currently incomplete. Cytokine gene polymorphisms warrant consideration as factors explaining variation in the human immune and inflammatory responses and as candidate susceptibility genes for related pathological states. Interleukin 12 (IL-12) is a key regulator of the polarisation of immune responses to T helper 1 or 2 categories and plays a role in autoimmune and infectious diseases. Using a bioinformatic strategy, we aligned cDNA and expressed sequence tag sequences to identify putative polymorphic regions of the IL-12 p40 gene. Position 1188 in the 3' untranslated region (UTR) was polymorphic with the frequency of the common allele around 80% in healthy UK Caucasoids. PCR genotyping of multiple Caucasoid groups and an African group showed significant population variation. In a case-control design, the polymorphism was not associated with rheumatoid arthritis, Felty's syndrome or large granular lymphocyte syndrome with arthritis or multiple sclerosis. A nonsignificant increase in the B allele frequency was observed in the rare large granular lymphocyte syndrome without arthritis (odds ratio 2.02 95% CI 0.95-4.3). This new genetic marker could be useful in anthropological studies and should be investigated in other autoimmune, allergic, inflammatory and infectious diseases.  相似文献   
59.
The association of certain HLA-DRB1 alleles in Greek rheumatoid arthritis (RA) patients with several features of the disease, the gender of the patient and the age at onset was investigated. This case control study includes 86 Greek RA patients and 130 healthy controls unrelated to the patients. HLA typing was performed by polymerase chain reaction (PCR) and hybridization with sequence-specific oligonucleotide (SSO) probes. HLA-DR4 was significantly increased in RA patients. The alleles *0101, *0401, *0405 and *1001 were associated with a higher risk of RA. The *0408 allele was absent from our patients. Sixty-five per cent of RA patients carried the ‘shared epitope’ (SE) compared with 31.5% of controls. The risk for RA in individuals carrying a single allele positive for SE was 2.85 times higher, and for those carrying two alleles positive for SE 8.57 times higher, than in SE-negative individuals. The risk was higher in those carrying the *0401 allele, followed by *0405 and *0101, while the genotype *0401/*0404 was absent. Alleles positive for SE comprise a predisposing factor for RA at an early age, particularly in men, and are associated with positive rheumatoid factor, nodules and erosions.  相似文献   
60.
Abstrakt Bei einem Arzt, der zahlreiche Taten des Abrechnungsbetruges über einen mehrj?hrigen Zeitraum begangen hat, ist ein l?ngerer Reifeprozess für die Wiedererlangung der Zuverl?ssigkeit erforderlich. Dass der Arzt in Zukunft nur noch privat?rztlich t?tig sein will, ist ohne Bedeutung.  相似文献   
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