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61.
Cystic-glandular cystitis is considered as part of the urothelial pre-neoplastic proliferative abnormalities. This group includes atypical hyperplasia. Von Brunn's nidus, and cystitis cystica. They are a consequence of the changes experienced at the urothelium level in response to inflammation, irritation or carcinogens. Diagnosis is mainly based in the pathoanatomical study of the biopsy obtained following endoscopic resection. The signs and symptoms it presents are varied and show a clear relationship to distribution and extension of cysts. Treatment is based in the removal of irritative factors. Cystectomy with urinary by-pass may be necessary if required by clinical evolution.  相似文献   
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Yang  GY; Liao  J; Kim  K; Yurkow  EJ; Yang  CS 《Carcinogenesis》1998,19(4):611-616
In order to study the biological activities of tea preparations and purified tea polyphenols, their growth inhibitory effects were investigated using four human cancer cell lines. Growth inhibition was measured by [3H]thymidine incorporation after 48 h of treatment. The green tea catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin (EGC) displayed strong growth inhibitory effects against lung tumor cell lines H661 and H1299, with estimated IC50 values of 22 microM, but were less effective against lung cancer cell line H441 and colon cancer cell line HT-29 with IC50 values 2- to 3- fold higher. (-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was even less effective. Preparations of green tea polyphenols and theaflavins had higher activities than extracts of green tea and decaffeinated green tea. The results suggest that the growth inhibitory activity of tea extracts is caused by the activities of different tea polyphenols. Exposure of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the induction of apoptosis as determined by an annexin V apoptosis assay, showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM of these compounds, the apoptosis indices were 82, 76 and 78%, respectively. Incubation of H661 cells with EGCG also induced a dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused apoptosis in a manner similar to that caused by EGCG. The EGCG-induced apoptosis in H661 cells was completely inhibited by exogenously added catalase (50 units/ml). These results suggest that tea polyphenol-induced production of H2O2 may mediate apoptosis and that this may contribute to the growth inhibitory activities of tea polyphenols in vitro.   相似文献   
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Esophageal cancer has been associated with tobacco smoking, and nitrosamines are possible causative agents for this cancer. The present study investigated the metabolism of the tobacco carcinogens N'- nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone (NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of xenobiotic-metabolizing enzymes in human esophageal tissues from individuals in the United States and Huixian, Henan Province, China (a high-risk area for esophageal cancer). All esophageal microsomal samples activated NNN and the metabolic rate was 2-fold higher in the esophageal samples from China than the USA. All microsomal samples activated NDMA. However, most of the microsomal samples did not activate NNK. Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation of NNN-derived keto acid by 20-26% in the esophageal microsomes. The activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase, NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present in the esophageal samples. Coumarin 7-hydroxylase (a representative activity for P450 2A6) activity was not detected in the esophageal microsomal samples. The activities for nitrosamine metabolism and xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous cell carcinomas compared with their corresponding non-cancerous mucosa. The presence of activation and detoxification enzymes in the esophagus may play an important role in determining the susceptibility of the esophagus to the carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and 2E1 are involved in the activation of NNN and NDMA, respectively, in the human esophagus.   相似文献   
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CONTEXT: There is a need for community-based, culturally sensitive, cognitive-behavioral interventions to reduce sexual risk behavior among minority adolescents. Studies of adolescent risk and protective behaviors have focused on identifying modifiable psychosocial variables that predict differential outcomes for subsequent intervention efforts. Research has been scarce in studies of rural minority adolescent women. PURPOSE: To examine the protective and risk behaviors of these rural Mexican-American adolescent women and their relationship to physical or sexual abuse. METHODS: Mexican-American adolescent women aged 14-19 years were recruited through a rural health clinic and administered a self-report assessment for protective and risk behavior and sexual, physical, and psychological abuse. FINDINGS: Rural minority adolescent women endured high levels of psychological distress and many risk behaviors yet experienced few protective behaviors. Barriers to health care included access and confidentiality. Physically or sexually abused adolescents endured relatively greater risk and fewer protective behaviors than nonabused. CONCLUSIONS: Rural Mexican-American adolescent women may benefit from confidential identification and assessment of abuse history and risk and protective behaviors so that appropriate psychological treatment can accompany accessible medical treatment. The prevalence of risk behaviors and abuse among these women presents a need for development of behavioral interventions for risk reduction and promotion of health protective behaviors.  相似文献   
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OBJECTIVE: Tissue microarray (TMA) technology allows simultaneous examination of the expression of many molecular markers (protein, mRNA, DNA, etc.) with high-throughput. The application of this technology, to date, has been largely confined to the study of cancer. Placental pathology poses unique challenges because of the size of the organ, its complex anatomy, as well as its histological heterogeneity. The objective of this study was to assess the feasibility and efficiency of TMAs for immunohistochemistry and in situ hybridization of placental tissues. STUDY DESIGN: TMAs were constructed using an automated tissue arrayer. Standard 0.6-mm or 1-mm microarray needles were used. Villous parenchyma, basal plate, and chorioamniotic membranes were targeted in each block. Five mum-thick TMA sections underwent immunohistochemical analysis of both cytoplasmic and nuclear antigens using a panel of antibodies against a variety of cytoplasmic [cytokeratin-7, vascular endothelial growth factor (VEGF), and protein Z], membranous (endoglin), and nuclear (c-fos and c-jun) antigens. mRNA in situ hybridization for surfactant protein A (SP-A) and chromogenic in situ hybridization for the Y chromosome (DYZ1) were also performed. RESULTS: Validation of TMA immunoreactivity demonstrated comparable results with corresponding whole sections. When a two-tiered scoring system (positive/negative) was employed, there was agreement between two and three cores and whole tissue sections (kappa>0.7). When a three-tiered scoring system (negative, weak-positive, or strong-positive) was used, the data from three cores showed the highest agreement with whole tissue sections (kappa >0.7). In situ hybridization experiments for mRNA and DNA were also successful in that the signals were readily detectable. Successful transfer from the donor block to the recipient block differed according to the anatomical compartment. The transfer efficiency of villous parenchyma, basal plate, and chorioamniotic membranes were 96.9% (875/903), 76.7% (115/150), and 75.4% (224/297), respectively. CONCLUSION: TMA is a practical and effective tool for high-throughput molecular analysis of the human placenta. Duplicate and triplicate cores offer agreement with whole tissue sections for two-category distinction immunostaining. TMA also affords relevant results from in situ hybridization experiments for mRNA and DNA. The major advantages are the conservation of tissues and reagents, simultaneous comparison of molecular markers in different anatomical compartments of the placenta, and reduction of experimental error.  相似文献   
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There is evidence that B vitamins produce antinociception in animals. However, potentiation of NSAID‐induced antinociception by B vitamins is unclear. The current study was designed to investigate the antinociceptive interaction between a mixture of B vitamins and either acetaminophen or metamizol. Acetaminophen (56–316 mg/kg), metamizol (32–178 mg/kg), and the mixture of B vitamins (32–178 mg/kg of thiamine, pyridoxine, and cyanocobalamin in a 100:100:1 proportion, respectively) or a combination of each drug with the B vitamins mixture was administered orally to female Wistar rats, and the antinociceptive effect determined in the formalin test. Isobolographic analyses were used to define the nature of the interaction between NSAIDs and B vitamins. Oral administration of either drug produced a dose‐related antinociceptive effect. Isobolographic analyses revealed that both acetaminophen or metamizol and the B vitamins mixture interacted synergistically in the formalin test, suggesting that these two combinations could be useful in treating inflammatory pain states. Drug Dev. Res. 66:286–294, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   
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This study evaluated the effects of hepatic fibrosis on the multiexponential T2 (MET2) relaxation of ex vivo murine liver specimens using an 11.7 T MRI. This animal study was approved by the Institutional Animal Care and Use Committee. Eighteen male C57BL/6 mice were divided into control (n = 3) and experimental (n = 15) groups; the latter group was fed a 3,5‐dicarbethoxy‐1,4‐dihydrocollidine‐supplemented diet to induce hepatic fibrosis. Ex vivo liver specimens were imaged using an 11.7 T MRI scanner. A multi‐echo spin‐echo sequence was utilized for subsequent MET2 analysis. Degrees of fibrosis were determined by a pathologist, as well as by digital image analysis. Scatterplot graphs comparing various features of the MET2 signal decay with the degrees of fibrosis were generated, and correlation coefficients were calculated. Two distinct peaks of the MET2 signal decay were identified in all liver specimens: a short T2 component with a geometric mean T2 (GMT2) approximating 30 ms; and a long T2 component with GMT2 approximating 400 ms. Strong correlation was found between the degree of hepatic fibrosis and the amplitude of the short T2 component, with a higher degrees of fibrosis associated with a lower amplitude. Moderate correlation was also found between hepatic fibrosis and the GMT2 values of the long T2 component, with higher degrees of fibrosis associated with lower GMT2 values. The study of hepatic microenvironments using MET2 analyses offers potential utility in the ongoing development of the noninvasive assessment of hepatic fibrosis using MRI. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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