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61.
OBJECTIVES: Current knowledge of the cardiac manifestations of rheumatoid arthritis (RA) stems only from clinical and transthoracic echocardiography (TTE) studies. To determine the incidence and type of heart lesions in RA, we coupled TTE with transesophageal echocardiography (TEE), which is more sensitive and more accurate. METHODS: Thirty unselected RA patients (26 women and 4 men aged 27 to 84 years, with a mean age of 57.8+/-15.1 years) free of known progressive heart disease underwent a chest radiograph, an electrocardiogram, laboratory tests, and TTE coupled with TEE. Results were compared with those in age- and sex-matched patients who were free of rheumatic disease and who underwent TEE to investigate a neurologic or cardiologic disorder. RESULTS: Mitral regurgitation (MR) was evidenced in 24 cases (80%). Among the controls, only 11 (37%) had MR (P < 0.001). Aortic regurgitation was found in 10 cases (33%), versus 7 controls (not significant-NS). Seven cases (23%) versus only 2 controls (7%) had tricuspid valve abnormalities (NS). Pericarditis was found in 4 cases (13%) and in none of the controls. Eleven cases had evidence of cardiomyopathy (37%) and 12 (40%) had atheroma of the aorta, this last being missed by TTE in 10 patients. Echo-generating nodules were seen on a mitral valve in 2 cases and on an aortic valve in 1. We found no correlations linking cardiac lesions to clinical or laboratory features of RA. CONCLUSION: Our study demonstrated that cardiac involvement, particularly of the mitral valve, is extremely common in RA patients.  相似文献   
62.
BACKGROUND: Malaria represents one of the most important infectious disease threats to deployed military forces; most personnel from developed countries are nonimmune personnel and are at high risk of infection and clinical malaria. This is especially true for forces deployed to highly-endemic areas in Africa and Southeast Asia where drug-resistant malaria is common. METHODS: We conducted an outbreak investigation of malaria cases in Angola where a total of 439 nonimmune Brazilian troops were deployed for a 6-month period in 1995-1996. A post-travel medical evaluation was also performed on 338 (77%) of the 439 soldiers upon return to Brazil. Questionnaire, medical record, thick/thin smear, and serum anti-Plasmodium falciparum antibody titer (by IFA) data were obtained. Peak serum mefloquine (M) and methylmefloquine (MM) metabolite levels were measured in a subsample of 66 soldiers (42 cases, 24 nonmalaria controls) who were taking weekly mefloquine prophylaxis (250 mg). RESULTS: Seventy-eight cases of malaria occurred among the 439 personnel initially interviewed in Angola (attack rate = 18%). Four soldiers were hospitalized, and 3 subsequently died of cerebral malaria. Upon return to Brazil, 63 (19%) of 338 soldiers evaluated were documented to have had clinical symptoms and a diagnosis of malaria while in Angola. In addition, 37 (11%) asymptomatically infected individuals were detected upon return (< 1% parasitemia). Elevated, post-travel anti-P. falciparum IFA titers (> or = 1:64) were seen in 101 (35%) of 292 soldiers tested, and was associated with a prior history of malaria in-country (OR = 3.67, 95% CI 1.98-6.82, p <.001). Noncompliance with weekly mefloquine prophylaxis (250 mg) was associated with a malaria diagnosis in Angola (OR = 3.75, 95% CI 0.97-17.41, p =.03) but not with recent P. falciparum infection (by IFA titer). Mean peak levels (and ratios) of serum M and MM were also found to be lower in those who gave a history of malaria while in Angola. CONCLUSIONS: Malaria was a significant cause of morbidity among Brazilian Army military personnel deployed to Angola. Mefloquine prophylaxis appeared to protect soldiers from clinical, but not subclinical, P. falciparum infections. Mefloquine noncompliance and an erratic chemoprophylaxis prevention policy contributed to this large outbreak in nonimmune personnel. This report highlights the pressing need for development of newer, more efficacious and practical, prophylactic drug regimens that will reduce the malaria threat to military forces and travelers.  相似文献   
63.
Objectives: This study assessed the inequality in caries distribution and the association between socioeconomic indicators and caries experience of preschool children in a city in Brazil. Methods: A cross‐sectional study in a multistage random sample of 455, 1‐5‐year‐old children was conducted on National Children's Vaccination Day in Santa Maria, Brazil. Calibrated examiners evaluated the prevalence of dental caries and parents provided information about several socioeconomic indicators by means of a semi‐structured questionnaire. Data were analyzed using Poisson regression model. Results: The caries prevalence was 23.5 percent and the means for the decayed, missing and filled primary teeth was 0.8. A high inequality in the caries distribution with Gini coefficient of 0.8 and Significant Caries Index of 2.8 was observed. The oldest children, non‐white, with mothers having low level of education and from low household income had the highest prevalence of dental caries. Conclusion: Socioeconomic factors are strong predictors for the inequality in caries distribution in Brazilian preschool children.  相似文献   
64.
Alcohol abuse is an important public health problem. In Portugal with a population of 10 millions of inhabitants, there are around 10% of alcoholics or excessive alcohol drinkers and 1% of chronically infected patients with hepatitis B virus (HBV). To examine the characteristics of patients with higher levels of alcohol consumption and to investigate the association between alcohol consumption and liver damage a total of 298 chronically infected individuals, with HBV genotyped and submitted to liver biopsy, were classified with Child's grading and separated by habits of alcohol intake, less and greater than 20 g/day. No significant differences were observed about genotype but genotypes A and D were predominant in both of them. A higher percentage of males (P < .001) were observed in the group with alcohol intake above 20 g/day, as well a lower proportion of patients with HBeAg negativity (P ≤ .035). In this group, biochemistry parameters, such as alanine aminotransferase (P = .006), aspartate aminotransferase (P = .001), gamma-glutamyl transferase (P < .001) were elevated in a significantly higher proportion than in the other group. The analysis of hematological parameters showed significantly lower values of platelets (P = .042) and mean corpuscular volume (P < .001) and significantly higher values of prothrombin time (P < .001) in the group with higher levels of alcohol consumption. The characteristics of biopsy (P < .001) and Child-Phug's classification (P = .002) revealed more severe results in this group. Logistic regression showed a positive association between liver damage and alcohol intake, increasing with age. In female patients, a strong positive association between alcohol intake and liver damage was also found (odds ratio: 9.379; 95% confidence interval: 0.859-468.422; P = .037); however, the most severe cases were only observed in women older than 45 years. In patients with HBV infection, alcohol is associated with a more severe liver disease. No evidence was found concerning association with HBV genotype.  相似文献   
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66.
A pharmacokinetic model incorporating saturable rate of absorption of the Michaelis-Menten type was recently developed to fit cefatrizine (CFZ) plasma concentrations with time following oral administration of 500-mg capsules to humans. This model (MM) was statistically superior to models incorporating either first-order or zero-order absorption. However, the MM model does not predict the reduction in extent of absorption with dose observed in vivo. In this study, a model is proposed in which a time constraint, delta t, is added to the MM model. This new model (MM-delta t) is tested with data following doses of 250, 500, and 1000 mg of CFZ. When delta t is set to 1.5 hr, the predicted relative changes with dose in bioavailability, F, peak plasma concentration, Cmax, the time at which the peak concentration occurs tmax, and the mean absorption time, MAT, are generally in good agreement with the experimental data. The time interval of 1.5 hr is compatible with passage by a limited region within the small intestine where drug is absorbed by a facilitated transport mechanism. Influence of each absorption model parameter (Vmax, Km, and delta t) on total area under the concentration versus time curve (AUC), F, Cmax, and tmax, is assessed by simulation. The MM-delta t model is able to summarize the nonlinerity observed in both rate and extent of absorption.  相似文献   
67.
The increasing use of carboplatin and paclitaxel for the treatment of cancer, especially in ovarian and lung carcinomas has led to the observation of a growing number of hypersensitivity reactions to these drugs. Hypersensitivity to carboplatin usually appears in heavily pre-treated patients, and it is difficult to use carboplatin in posterior treatments. Hipersensitivity to paclitaxel, in contrast, usually takes place during the first or second infusions, although frequently it can be used again safely with a correct premedication or with the appropriate desensitization techniques. We review here the clinical, diagnostic and therapeutic management of hypersensitivity to carboplatin and paclitaxel. We provide the guidelines for the correct distinction between the two types of reactions and the clinical management.  相似文献   
68.
An enzyme-linked immunosorbent assay (ELISA), employing antigens from Toxocara canis larvae and the absortion of suspected sera with Ascaris lumbricoides extracts was used in a seroepidemiological study performed in five municipalities of S?o Paulo State, Brazil (S?o Paulo, Campinas, Santos, Marília and Presidente Prudente) in order to determine the frequency of antibodies to Toxocara. In 2,025 blood samples collected, 806 proceeded from male subjects and 1,219 from females; 483 samples were collected from subjects under 15 years of age and the remaining 1,542 from subjects aged 15 years or over. Among the 2,025 sera investigated, 3.60% had antibodies to Toxocara at significant levels. A moderate predominance of infection with Toxocara among male subjects (3.72%) was observed, although the difference was not statistically significant when this rate was compared with that for female (3.28%). Related to age, a higher frequency of positive results was detected among subjects under 15 years (6.41%) against the older group (2.53%). A trend of more elevated rates of infection was observed in municipalities with high demographic densities (S?o Paulo, Campinas and Santos). Nevertheless, such findings only appeared to be statistically significant in subjects younger than 15 years.  相似文献   
69.
70.
Background: The ability to recognize and interpret emotions in others is a crucial prerequisite of adequate social behavior. Impairments in emotion processing have been reported from the early stages of Parkinson’s disease (PD). This study aims to characterize emotion recognition in advanced Parkinson’s disease (APD) candidates for deep-brain stimulation and to compare emotion recognition abilities in visual and auditory domains. Method: APD patients, defined as those with levodopa-induced motor complications (N = 42), and healthy controls (N = 43) matched by gender, age, and educational level, undertook the Comprehensive Affect Testing System (CATS), a battery that evaluates recognition of seven basic emotions (happiness, sadness, anger, fear, surprise, disgust, and neutral) on facial expressions and four emotions on prosody (happiness, sadness, anger, and fear). APD patients were assessed during the “ON” state. Group performance was compared with independent-samples t tests. Results: Compared to controls, APD had significantly lower scores on the discrimination and naming of emotions in prosody, and visual discrimination of neutral faces, but no significant differences in visual emotional tasks. Conclusion: The contrasting performance in emotional processing between visual and auditory stimuli suggests that APD candidates for surgery have either a selective difficulty in recognizing emotions in prosody or a general defect in prosody processing. Studies investigating early-stage PD, and the effect of subcortical lesions in prosody processing, favor the latter interpretation. Further research is needed to understand these deficits in emotional prosody recognition and their possible contribution to later behavioral or neuropsychiatric manifestations of PD.  相似文献   
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