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991.
This study aimed to describe the temporal-spatial patterns of dengue epidemics in Belo Horizonte, Minas Gerais State, Brazil, from 1996 to 2002 and to analyze residential address as a proxy for exposure. Reported dengue cases were analyzed according to week of onset of symptoms and residential census tract. Local Moran's index was used to assess spatial autocorrelation of incidence coefficients, and recurrent census areas over different epidemic waves were also verified. Ripley's K-function was used to compare spatial distribution patterns between the two population groups, assuming that they were distributed differently around the city. A total of 99,559 dengue cases were analyzed, resulting in seven epidemic waves with different durations and intensities, with cases clustering in a small fraction of areas, thinning out both spatially and temporally. Distinct case distribution patterns were observed according to the two exposed groups, suggesting the need to improve the reporting of possible place of infection. The observed endemic pattern of the disease also requires specific strategies and poses a major challenge for health surveillance services.  相似文献   
992.
This was a cross-sectional study of workers in the pre-hospital care team in Belo Horizonte, Minas Gerais State, Brazil, aimed at evaluating adherence to precautions. The study instrument included questions on knowledge, attitudes, and facilitating factors for adherence to standard precautions. Adherence was verified by percentage of adequacy: > 75% correct answers. Drivers showed the lowest degree of knowledge and physicians the highest. In self-reported answers, none of the workers demonstrated adequate use of face masks, goggles, or personal protective equipment (PPE), and drivers reported inadequate attitudes on all the items. In the univariate analysis, job position, gender, and specific rescue unit were associated with adoption of precautions. Meanwhile, in the multivariate analysis, only job position was related (drivers and nurse technicians/aides). The most frequently cited facilitating factors for improvement of adherence were: training focusing on infections, occupational risks, and use of PPE; periodic team meetings; and creation of a central unit for cleaning, disinfecting, and sterilizing equipment and materials. Workers in the pre-hospital care service demonstrated attitudes that were compatible with knowledge, but professional class affected knowledge on standard precautions and self-reported adequate attitudes.  相似文献   
993.
This study reports the results of 12 focus group interviews with primary school students (7-10 years old, n=57) in Florianópolis, Brazil, regarding their food choices, television (TV) viewing, and physical activity habits. In 2005, an average Brazilian child aged 4-11 years watched TV almost 5 h per day. Intensive TV use in childhood and adolescence may contribute to sedentarism and unhealthy eating habits, and excessive viewing might have long-lasting adverse effects on health. Results indicated that frequent ingestion of snack foods was not a habit for most students, possibly because of an acknowledged parental interference, but these were the food items they bought with their own money. Daily TV viewing was reported by almost all students, especially during meals and before bedtime, but students still found the time to be physically active. Most of them mentioned going to sports classes and engaging in active play regularly. No attempts by the parents to regulate TV viewing in the household were mentioned. The habit of eating while watching TV, together with the students' behavior as primary consumers of food products, pointed to the need for strategies that will reduce TV viewing and educate the children as consumers.  相似文献   
994.
The aim was to evaluate the effect of control selection on risk factor analysis for extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-KP) infections. Four contemporaneous case-control studies were conducted prospectively with 372 patients: Study 1 (ESBL-KP-infected vs non-infected); Study 2 (ESBL-KP-infected vs non-ESBL-KP-infected); Study 3 (all KP-infected vs non-infected); Study 4 (non-ESBL-KP-infected vs non-infected). Time at risk (TAR, i.e. duration of hospital stay) was the most significant risk factor [Study 1: odds ratio (OR): 5.74 (95% CI: 2.26-14.59; P<0.001); Study 2: 3.52 (1.47-8.43; P=0.005); Study 3: 2.68 (1.57-4.58; P<0.001)]; central venous catheterisation (CVC) was a risk factor in Study 1: 5.31 (1.67-16.82; P=0.005) and Study 3: 2.10 (1.04-4.27; P=0.04). Prior use of cephalosporins (PUC) was a risk factor only in studies with non-infected patients as controls [Study 1: 5.64 (1.90-16.72; P=0.002) and Study 3: 4.60 (2.09-10.13; P<0.001)]. The ORs were uniformly lower with 'non-ESBL-KP-infected' (TAR: 3.52; CVC: 2.07; PUC: 1.97) compared with 'non-infected' patients (TAR: 5.74; CVC: 5.31; PUC: 5.64) as control groups. Selection of control patients has a crucial role in the evaluation of risk factors for ESBL-KP infections. A consistent underestimation of the magnitude of the risk factors is observed when the control group is defined by the non-ESBL-KP-infected patients.  相似文献   
995.
In order to evaluate the effects of uncertainty about direction of mechanical perturbation and supra-postural task constraint on postural control, young adults had their upright stance perturbed while holding a tray in a horizontal position. Stance was perturbed by moving forward or backward a supporting platform, contrasting situations of certainty versus uncertainty of direction of displacement. Increased constraint on postural stability was imposed by a supra-postural task of equilibrating a cylinder on the tray. Performance was assessed through EMG of anterior leg muscles, angular displacement of the main joints involved in the postural reactions and displacement of the tray. Results showed that both certainty on the direction of perturbation and increased supra-postural task constraint led to decreased angular displacement of the knee and the hip. Furthermore, combination of certainty and high supra-postural task constraint produced shorter latency of muscular activation. Such postural responses were paralleled by decreased displacement of the tray. These results suggest a functional integration between the tasks, with central set priming reactive postural responses from contextual cues and increased stability demand.  相似文献   
996.
This ecological study analyzed the association between pesticide use and prematurity, low weight and congenital abnormality at birth, infant death by congenital abnormality, and fetal death in Brazil in 2001. Simple linear regression analysis has determined a positive association between pesticide use and prematurity, low birth weight, and congenital abnormality. The association between pesticide use and low birth weight (p = 0.045) and, congenital abnormality (p = 0.004) and infant death rate by congenital abnormality (p = 0.039) remained after the adjustment made by the proportion of pregnant women with a low number of prenatal care visits.  相似文献   
997.
998.
Selection of the appropriate donor is essential to a successful allograft recipient outcome for solid organ transplantation. Multiple infectious diseases have been transmitted from the donor to the recipient via transplantation. Donor-transmitted infections cause increased morbidity and mortality to the recipient. In recent years, a series of high-profile transmissions of infections have occurred in organ recipients prompting increased attention on the process of improving the selection of an appropriate donor that balances the shortage of needed allografts with an approach that mitigates the risk of donor-transmitted infection to the recipient. Important advances focused on improving donor screening diagnostics, using previously excluded high-risk donors, and individualizing the selection of allografts to recipients based on their prior infection history are serving to increase the donor pool and improve outcomes after transplant. This article serves to review the relevant literature surrounding this topic and to provide a suggested approach to the selection of an appropriate solid organ transplant donor.  相似文献   
999.

Objective

To determine human papillomavirus (HPV) genotypes and the physical status of HPV-16 DNA among women from northern Portugal with cervical lesions.

Methods

The present retrospective study included samples of cervical exfoliated cells from 88 women (median age 42.0 ± 13.1 years) who attended the Gynecology Service at the Portuguese Institute of Oncology in Porto during 2010. After DNA extraction, HPV genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism analysis using the MY09/MY11 primers. The physical status of HPV-16 was determined by real-time PCR.

Results

Overall, 69.3% of the samples tested positive. The prevalence of HPV infection was 38.5% in normal samples, 57.7% in cervicitis samples, and 87.2% in all cervical lesions including invasive cancers. Sixteen genotypes were detected, the most prevalent ones being HPV-16 (42.9%), HPV-31 (12.2%), and HPV-58 (10.2%); HPV-18 was rare. The overall prevalence of HPV-16 integration was 31.6%. The physical status of HPV-16 did not differ significantly by histology.

Conclusion

The most frequent genotypes were HPV-16, -31, and -58. Integration of HPV-16 DNA seemed to be an early event in cervical carcinogenesis. Further studies are required to clarify the value of viral integration as a prognostic marker.  相似文献   
1000.
Objective: Obesity has been associated with increased risk for breast cancer (BC) mortality. Verifying in women with high breast density (HBD) post-menopausal, the frequency of polymorphisms of estrogen receptor (ER)α-PvuII, ERα-XbaI and if they influence the body mass index (BMI).

Methods: Study with 308 women with HBD post-menopause divided into two groups according to BMI: 1st group?=?BMI?2, 2nd group?=?BMI?≥?25?kg/m2. It was characterized in the clinical history: menarche, menopause, parity, family history of BC, smoking and alcohol intake.

Results: Allele and genotype frequencies for the ERα-397-Pvull and ERα-351-XbaI: P?=?43.99%, p?=?56.01%, pp?=?32.14%, Pp?=?47.73%, PP?=?X?=?20.13% and X?=?41.56%, x?=?58.44%; xx?=?33.44%; Xx?=?50.00%; XX?=?16.56%, respectively. Both PvuII and XbaI influenced BMI. When XbaI is mutated the tendency is toward higher BMI (0.039), and women with lower BMI were more frequent in PvuII genotype (p?=?0.002). More frequent risk factors for BC: menarche before the age of 12 years (35.38%), nulliparity or 1st child after 28 years old (41.66%), family history of BC (19.16%) and overweight/obesity (62.01%).

Conclusion: Variations in the ERα gene affected the BMI in women with HBD, who already are at increased risk for BC.  相似文献   
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