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991.
Epidemiological investigation of foodborne disease outbreaks helps us to better define the risks, hazards and vehicles involved. In 1997 guidelines on epidemiological methods for investigating these outbreaks were implemented in the Lazio Region. Methods used in investigating the 410 foodborne disease outbreaks reported in the 1996-2000 period were analysed to evaluate the impact of the guide lines on health services. Specific food attack-rates (epidemiological methods) were calculated more frequently in outbreaks with setting of mass catering with many exposed people (46% of these outbreaks) than in outbreaks in home setting with few exposed people (13% of these cases). Inversely, in smaller outbreaks the proportion of cases with detected aetiology (microbiological method) was higher (66%) than in larger ones (43%). For foodborne disease outbreaks with at least 30 people exposed epidemiological methods of investigating showed temporal trend in the period 1996-2000: the epidemics in which attack rates were calculated increased from 50% to 83%, those in which epidemic curve was drawn increased from 17% to 79%, and those in which food specific attack rates were calculated increased from 33% to 58%. The hazard analysis of critical control points (HACCP) was performed only in 18.3% of the cases. In conclusion, the guide lines resulted in a wider application of epidemiological methods in large outbreaks with a well defined exposure resulting in an improved detection of vehicles of foodborne diseases. Epidemiological methods possibly are not adequate to investigate smaller foodborne outbreaks.  相似文献   
992.
Eleven mosquito species, namely Aedes hastatus, Ae. fulvus, Coquillettidia albicosta, Cq. juxtamansonia, Culex aliciae, Cx. delpontei, Cx. oedipus, Cx. pedroi, Mansonia flaveola, Uranotaenia leucoptera, and Wyeomyia oblita, are recorded for the first time from northwestern Argentina. In addition, 3 species, Cx. brethesi, Limatus durhami, and Ur. nataliae, are reported for the first time from Salta Province. These records extend the geographical distribution of these 3 species to Salta Province. This study also extends the geographical distributions of Cq. nigricans, Cx. chidesteri, and Ma. humeralis to Jujuy Province and of Ae. meprai, Ae. milleri, Ae. oligopistus, Cx. brethesi, Cx. fernandezi, and Cx. tatoi to Tucumán Province.  相似文献   
993.
Multiagent DNA vaccines for highly pathogenic organisms offer an attractive approach for preventing naturally occurring or deliberately introduced diseases. Few animal studies have compared the feasibility of combining unrelated gene vaccines. Here, we demonstrate that DNA vaccines to four dissimilar pathogens that are known biowarfare agents, Bacillus anthracis, Ebola (EBOV), Marburg (MARV), and Venezuelan equine encephalitis virus (VEEV), can elicit protective immunity in relevant animal models. In addition, a combination of all four vaccines is shown to be equally as effective as the individual vaccines for eliciting immune responses in a single animal species. These results demonstrate for the first time the potential of combined DNA vaccines for these agents and point to a possible method of rapid development of multiagent vaccines for disparate pathogens such as those that might be encountered in a biological attack.  相似文献   
994.

Background

Mounting evidence shows that multi-intervention programmes for hypertension treatment are more effective than an isolated pharmacological strategy. Full economic evaluations of hypertension management programmes are scarce and contain methodological limitations. The aim of the study was to evaluate if a hypertension management programme for elderly patients is cost-effective compared to usual care from the perspective of a third-party payer.

Methods

We built a cost-effectiveness model using published evidence of effectiveness of a comprehensive hypertension programme vs. usual care for patients 65 years or older at a community hospital in Buenos Aires, Argentina. We explored incremental cost-effectiveness between groups. The model used a life-time framework adopting a third-party payer's perspective. Incremental cost-effectiveness ratio (ICER) was calculated in International Dollars per life-year gained. We performed a probabilistic sensitivity analysis (PSA) to explore variable uncertainty.

Results

The ICER for the base-case of the "Hypertension Programme" versus the "Usual care" approach was 1,124 International Dollars per life-year gained. PSA did not significantly influence results. The programme had a probability of 43% of being dominant (more effective and less costly) and, overall, 95% chance of being cost-effective.

Discussion

Results showed that "Hypertension Programme" had high probabilities of being cost-effective under a wide range of scenarios. This is the first sound cost-effectiveness study to assess a comprehensive hypertension programme versus usual care. This study measures hard outcomes and explores robustness through a probabilistic sensitivity analysis.

Conclusions

The comprehensive hypertension programme had high probabilities of being cost-effective versus usual care. This study supports the idea that similar programmes could be the preferred strategy in countries and within health care systems where hypertension treatment for elderly patients is a standard practice.  相似文献   
995.
Longitudinal predictors of dietary behavior change are important and in need of study. This secondary data analysis combined primary data across three randomized trials to examine transtheoretical model (TTM) and specific dietary predictors of successful dietary change at 12 and 24 months separately in treatment and control groups (N = 4178). The treatment group received three TTM-tailored print interventions over 12 months between 1995 and 2000. Chi-square and MANOVA analyses were used to examine baseline predictors of dietary outcome at 12 and 24 months. Last, a multivariable logistic regression was conducted with all baseline variables included. Across all analyses in both treatment and control groups, the most robust predictors of successful change were for TTM-tailored treatment group, preparation stage of change, and increased use of dietary behavior variables such as moderating fat intake, substitution of lower fat foods, and increasing intake of healthful foods. These results provide strong evidence for treatment, stage and behavioral dietary severity effects predicting dietary behavior change over time, and for targeting these variables with the strongest relationships to outcome in interventions, such as TTM-tailored dietary interventions.  相似文献   
996.
Objective: The negative effects on cheese quality of milk contaminated by spores of Clostridium butyricum and Cl.tyrobutyricum is prevented by the use of egg white lysozyme as additive. Since the presence of lysozyme in cheese could be possibly risky in allergic subjects, we aimed at investigating its absorption as well as serum IgE antibody titers after ingestion of Grana Padano cheese, an Italian DPO, long-ripened hard cheese, in white egg allergic subjects.

Methods: Cheese lysozyme was measured by HPLC. Ten healthy volunteers and 20 patients with hen egg hypersensitivity, RAST positive (binding≥3%) to lysozyme and/or ovomucoid and ovalbumin received 15, 30 and 60 g of cheese at distance of at least 2 weeks each. Serum lysozyme was measured by ELISA and specific IgE binding to lysozyme by the radioallergosorbent test (RAST).

Results: The concentration of lysozyme in cheese was 155 ± 5 mg/kg. The area-under-the-curve of serum lysozyme after 15 g of cheese was 244.5 ± 14.0 in controls and 330.2 ± 9.9 in patients (p < 0.01). Similar results were obtained with 30 and 60 g of cheese. Only 3 patients (15%) showed positive IgE antibody responses to cheese (overall RAST mean 4.45 ± 1.25 % vs. 4.24 ± 1.02 % baseline, p = ns).

Conclusions: The amount of lysozyme absorbed with cheese was globally very low, although it was significantly lower in healthy controls than in allergic patients, where it induced an increase of IgE RAST score in 15% of subjects, without any clinical reaction. Therefore, the use of lysozyme as additive in Grana Padano cheese, does not appear to be harmful in egg allergic subjects.  相似文献   
997.
The objective of this study was to update mosquito species distribution in Argentine Patagonia based on new field collections and to examine the material deposited in the La Plata Museum. Culex coronator, Cx. brethesi, and Cx. castroi represented new records for the region, increasing mosquito fauna of Patagonia to 15 species. The expansion of the geographic distribution of Cx. apicinus, Cx. articularis, and Cx. eduardoi at the province level was also provided. Current knowledge about mosquito fauna of Patagonia is restricted mainly to geographic distribution records. Further studies on the bionomic of mosquito species in Patagonian conditions are needed.  相似文献   
998.
This is research of a qualitative nature that sought to analyze the perceptions of both the health team and users of the Pediatric Unit of the University Hospital of Santa Catarina Federal University with respect to the participation of dental surgeons in the healthcare of hospitalized children. Data were collected through interviews based on a form with semi-structured questions and analyzed by the content analysis technique and the analysis-reflection-synthesis process. Eight professionals from the health team, as well as seven caregivers and five hospitalized children took part in the interviews. The dental care provided to these children was given by students of the Undergraduate and Graduate Program in Dentistry, via an extension project of a preventive educational nature. Results revealed broad acceptance and perception of the importance of the participation of dentists in the context of the Unit as team members implementing the concept of comprehensive healthcare, and as support professionals for the health team in the care, streamlining and optimization of interdisciplinary work. Participants perceive the effective participation of dentists in the healthcare of hospitalized children as being very important and even essential.  相似文献   
999.
The genus Hantavirus, family Bunyaviridae, comprise at least 20 distinct viruses. Ten of these have been linked to specific human diseases. Hemorrhagic fever with renal syndrome has been recognized since the 1950s. Hantavirus pulmonary syndrome was recognized in the United States in 1993. Epizootiologic studies of Norway rats in the Baltimore area have shown that rodent infections with hantaviruses are common and geographically widespread with prevalence reaching 44% in tested rat populations. These viruses are antigenically related to the Seoul virus. Hantavirus infections in humans occur through transmission from a rodent reservoir, primarily by inhalation of virus laden rodent excreta. There is no evidence to support person-to-person transmission of any known Hantavirus. To establish the prevalence of Hantavirus infections in humans in the Baltimore area we collected sera from 1,212 persons attending a community based health care system. These were tested for antibodies against three reference Hantavirus strains: Hantaan (HTN), Seoul (SEO), and Convict Creek (HN017). HN017 was chosen to represent the SinNombre (SN-like) strains of Hantavirus. Sera from nine patients were positive to Hantavirus specific antibodies, HTN, and SEO by Enzyme Linked Imuno Sorbent Assay (ELISA). No sera were positive for HN017 antigen. All sera that were positive for HTN and SEO were tested by western blot for HTN. All nine sera were confirmed positive by western blot. This suggests that unrecognized infections with Hantaan or Seoul-like viruses occur in the Baltimore area in humans, although the prevalence rate in humans is low (0.74%). Epidemiologic monitoring may be warranted to establish the health implications of these infections.  相似文献   
1000.
In 2001, the Naval Health Research Center Toxicology Detachment was funded by the U.S. Army Medical Research Acquisition Activity (USAMRAA) to conduct a study of the effects of surgically implanted depleted uranium (DU) pellets on adult rat reproductive success and development across two successive generations. This article presents some of the findings for the group of offspring from adult rats mated at 30 d post surgical implantation of DU pellets. Adult male and female Sprague-Dawley rats (P1 generation) were surgically implanted with 0, 4, 8, or 12 DU pellets (1 x 2 mm). The P1 generation was then cross-mated at 30 d post surgical implantation. Urine collected from P1 animals at 27 d post surgical implantation showed that DU was excreted in the urine of DU-implanted animals in a dose-dependent manner. DU surgical implantation did not have a negative impact on P1 reproductive success, survival, or body weight gain through post surgical implantation d 90. There were no statistically significant differences in F1 birth weight, survival, and litter size at postnatal day (PND) 0, 5, and 20. No gross physical abnormalities identified in the offspring were attributable to neonatal DU exposure. A series of neurodevelopment and immune function assessments were also conducted on F1 offspring. No group differences were observed that were related to parental DU exposure. Studies are ongoing on the impact of leaving DU embedded in soft tissue for 120 d on rat reproduction and subsequent offspring survival and development.  相似文献   
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