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101.
The newborn mouse lung adenoma model has been shown to be asensitive test for studying the tumor-igenicity of bay regiondiol epoxides and their precursor dihydrodiols. When a totaldose of 28 nmol of 7, 12-dimethylbenz[a]anthracene (DMBA) orits derivatives was injected i.p. into the preweaning mice,it was found that the 3, 4-dihydrodiols of both DMBA and 7-hy-droxymethyl-12-methylbenz[a]anthracenecaused 13.3 and 4.1 times more lung adenomas than DMBA, respectively.The mice treated with the 5, 6- and 8, 9-dihydro-diols of DMBA,7-hydroxymethyl-12-methylbenz[a]-anthracene and its 5, 6- 8,9-and 10,11-dihydrodiols, 7-methyl-12-hydroxymethylbenz[a]an-thraceneand 7,12-dihydroxymethylbenz[a]anthracene developed a levelof lung adenomas/mouse less than Mold higher than that foundin the DMSO-treated control group. Liver tumors also developedin some of the mice. The percentage of mice with liver tumorsalso indicated that the 3, 4-dihydrodiols of both DMBA and 7-hydroxymethyl-12-methylbenz[a]anthracenewere more tumorigenic than DMBA itself. These data indicatethat the 3, 4-dihydrodiols of both DMBA and its 7-hydroxymethylderivative may be proximate carcinogenic metabolites of DMBAin the newborn mouse.  相似文献   
102.
Objective: The symptoms of depression experienced by women during the postnatal period may have profound effects on the lifelong health of both the mother and the child. In this randomized controlled study, we systematically evaluated the effects of weekly supportive group meetings for women with postnatal distress. Methods: Sixty postnatally distressed women were randomly assigned to support (n=30) and control (n=30) groups. Women assigned to the support group participated in four supportive group sessions that comprised discussions concerning transition to motherhood, postnatal stress management, communication skills, and life planning. Results: Subjects who attended the support sessions had significantly decreased scores on the Beck Depression Inventory (BDI) and the Perceived Stress Scale (PSS), and significantly increased scores on the Interpersonal Support Evaluation List (ISEL) as evaluated at the end of the fourth weekly session. In contrast, no significant changes were observed in the control group during this period. Conclusion: This is the first controlled study to provide evidence that participation in support groups for postnatally distressed women provides quantifiable psychosocial benefits.  相似文献   
103.
A 36-year-old male patient was scheduled to undergo ureteroscopic lithotomy because of left ureteral stone under spinal anesthesia. After receiving a renewed spinal anesthesia with 8 mg tetracaine to compensate for the first attempt (with 10 mg tetracaine), which proved to be a failure, he was soon seized with episodic seizure attacks. Central nervous system toxicity of the local anesthetic might be the cause of the seizure. We brought forward this case for discussion for warning that the possibility of systemic toxicity of local anesthetic might exist despite a seemingly undisputable spinal anesthesia.  相似文献   
104.
We studied the effects of intermittent exposure to aflatoxin B1 (AFB1) on hepatic DNA and RNA adduct formation. Fisher-344 male rats were fed 0.01, 0.04, 0.4, or 1.6 ppm of AFB1 intermittently for 8, 12, 16, and 20 weeks, alternating with 4 weeks of dosing and 4 weeks of rest. Other groups of rats were fed 1.6 ppm of AFB1 continuously for 4, 8, 12, and 16 weeks. Control rats received AFB1-free NIH-31 meal diet. AFB1-DNA and -RNA adducts were measured by HPLC with fluorescence detection. The data are presented as total DNA or RNA adducts. The DNA and RNA adduct levels increased or decreased depending on the cycles of dosing and rest. Rats removed from treatment 1 month after 1 or 2 dosing cycles (8 and 16 weeks of intermittent exposure) showed approximately a twofold decrease in DNA adduct levels and a two- to elevenfold decrease in RNA adduct levels compared with rats euthanized immediately after the last dosing cycle (12 and 20 weeks of intermittent exposure). Our data indicate that DNA and RNA adducts increased linearly, from 0.01 ppm to 1.6 ppm of AFB1 after 12 and 20 weeks of intermittent treatment. A linear dose response was also apparent for DNA but not for RNA adducts after 8 and 16 weeks of treatment. As biomarkers of exposure, AFB1-RNA adducts were three to nine times more sensitive than AFB1-DNA adducts but showed greater variability. These results suggest that binding of AFB1 to hepatic DNA is a linear function of the dose, regardless of the way this is administered. The dose-response relationship for RNA adducts depends on the length of the no-dosing cycles and on the turnover rate of RNA.  相似文献   
105.
Recombinant human relaxin as a cervical ripening agent   总被引:3,自引:0,他引:3  
Objective The aim of this study was to investigate the efficacy and safety of recombinant human relaxin (rhRIx) as a cervical ripening agent in women with an unfavourable cervix before induction of labour at term.
Design A multi-centre, double-blind, placebo-controlled trial performed in Edinburgh, Glasgow and Oxford. Women were treated with 0, 1, 2 or 4 mg of rhRIx in a gel vehicle administered intravaginally. Analysis of variance tests were performed on all continuous variables, and Cochran Mantel-Haenszel tests employed for all discrete variables.
Participants Ninety-six women at 37 to 42 weeks of gestation with a singleton pregnancy and a modified Bishop score of 4 were recruited.
Results There was no significant difference in the change in modified Bishop score between the four treatment groups. The lengths of the first and second stages of labour were similar in all 4 groups. PGE2 and oxytocin requirements were similar in all groups, as was the mode of delivery. There was no evidence that relaxin was absorbed systemically when given in this way.
Conclusion Recombinant human relaxin 1 to 4 mg, administered as an intravaginal gel, has no effect as a cervical ripening agent before induction of labour at term.  相似文献   
106.
Apoptosisisakindofcelldeathrecognizablebyaseriesofspecializedchangesinmorphological,biochemicalandmolecularbiologicalforms.Apoptosisisanactiveprocessofcelldestruction,characterizedbycellshrinkage,chromatinaggregationwitheXtensivegenomicfragmentation,crescentbodyformingbychromosomepyknosisalongthenuclearmargin.Intheapoptosis,endouncleaseasedependentCa2 andMg2 isactivated,thisenzymemakechromosomedegradedatthelinkersectionstofragmentsequivalenttosingleandmultiplenucleosomes.Thelatterarerevealeda…  相似文献   
107.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
108.
Microcystin-LR (MC-LR), a cyanobacterial toxin, is a potent inhibitor of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A). PP1 and PP2A are critical regulators in embryonic development. However, the effects of MC-LR in embryonic development have been controversial. MC-LR has been demonstrated to be highly toxic in medaka, but not in zebrafish or rabbit embryos. The causes of difference may be due to membrane impermeability that impaired the delivery of MC-LR into cytoplasm of zebrafish and rabbit embryos. Therefore, we microinjected MC-LR directly into developing zebrafish embryos and investigated the effects of MC-LR on embryonic development. We demonstrated that MC-LR induced the lethality of zebrafish embryos in a dose- and time-dependent manner. MC-LR also induced the loss of blastomere coherence via the interference of beta-catenin and cadherins distributions. Furthermore, the MC-LR treated fry revealed various developmental defects. These results suggested that MC-LR might affect the phosphorylation equilibrium of signaling molecules, including beta-catenin and cadherins, required early in zebrafish embryonic development.  相似文献   
109.
Chou  F.H.-C.  Chou  P.  Lin  C.  Su  Tom T.-P.  Ou-Yang  W.-C.  Chien  I.-C.  Su  C.-Y.  Lu  M.-K.  Chen  M.-C. 《Quality of life research》2004,13(6):1089-1097
This purpose of this study was to investigate the relationship between quality of life and psychiatric impairment in a Taiwanese community located near the epicenter of the 1999 earthquake, as assessed four to six months after the natural catastrophe. Trained assistants interviewed the 4223 respondents using the disaster-related psychological screening test (DRPST), an instrument specifically designed and validated by senior psychiatrists for assessment of psychiatric impairment after natural catastrophe. Additionally, the 36-Item Short-Form Health Survey (SF-36) was used to evaluate quality of life. The collected results were analyzed using Windows SPSS 10.0 software. Psychiatric impairment rated moderate to severe was assessed for 1448 (34.3%) of the responding residents. The 4223 respondents were divided into 4 psychiatric-impairment groups based on DPRST score: healthy (n = 952); mild impairment (n = 1823); moderate impairment (n = 1126); and, severe impairment (n = 322). The four groups were compared for a number of salient factors, including gender, age, current marital status and psychiatric-impairment score, to determine impact on quality of life. Respondents assessed as psychiatrically impaired tended to be older, female, divorced/widowed, and less educated, and they were more likely to have experienced major familial financial loss as an immediate consequence of the earthquake. Further, the greater the severity of the psychiatric impairment, the lower the scores for quality of life, for both the physical and mental aspects of this important general indicator.  相似文献   
110.
PURPOSE: To examine interactions between emotional intelligence (EI) and smoking risk factors on smoking intentions in adolescents. METHODS: EI ios defined as the ability to: accurately perceive, appraise, and express emotion; access and/or generate feelings in facilitating thought; understand emotion and emotional knowledge; and regulate emotions. EI of 416 6th graders (53% girls) from middle schools in the Los Angeles area (mean age = 11.3 years; 32% Latino, 29% Asian/Pacific Islander, 13% white, 19% Multiethnic, 6% Other) was assessed with an abbreviated version of the Multifactor Emotional Intelligence Scale, Adolescent Version (MEIS). This was a competence-based measure assessing an individual's ability to perceive, understand, and manage emotion. Logistic regression models were fit to test interactions between EI and ever trying cigarettes, hostility, and perceived ability to refuse a cigarette from someone just met, on intentions to smoke in the next year. RESULTS: High EI adolescents were more likely to intend to smoke in the next year if they had previously experimented with smoking. Those with low EI were more likely to intend to smoke if their perceived ability to refuse a cigarette offer from a person they just met was low or hostility level was high. CONCLUSIONS: These preliminary results indicate that EI interacts with risk factors to reduce smoking intentions, and contributes evidence to a link between EI and smoking in adolescents.  相似文献   
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