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41.
42.
《Vaccine》2015,33(45):6112-6119
BackgroundAttenuated vaccinia virus strain, LC16m8, defective in the B5R envelope protein gene, is used as a stockpile smallpox vaccine strain in Japan against bioterrorism: the defect in the B5R gene mainly contributes to its highly attenuated properties.MethodsThe protective activity of LC16m8 vaccine against challenge with a lethal dose of vaccinia Western Reserve strain was assessed in wild-type and immunodeficient mice lacking CD4, MHC class I, MHC class II or MHC class I and II antigens.ResultsThe immunization with LC16m8 induced strong protective activity comparable to that of its parent strain, Lister (Elstree) strain, in wild-type mice from 2 days to 1 year after vaccination, as well as in immunodeficient mice at 2 or 3 weeks after vaccination. These results implicated that the defect in the B5R gene hardly affected the potential activity of LC16m8 to induce innate, cell-mediated and humoral immunity, and that LC16m8 could be effective in immunodeficient patients.ConclusionLC16m8 with truncated B5 protein has an activity to induce immunity, such as innate immunity and subsequent cell-mediated and humoral immunity almost completely comparable to the activity of its parental strain Lister.  相似文献   
43.
《Vaccine》2015,33(24):2813-2822
BackgroundIn the first five I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe) influenza seasons vaccine effectiveness (VE) results were relatively homogenous among participating study sites. In 2013–2014, we undertook a multicentre case-control study based on sentinel practitioner surveillance networks in six European Union (EU) countries to measure 2013–2014 influenza VE against medically-attended influenza-like illness (ILI) laboratory-confirmed as influenza. Influenza A(H3N2) and A(H1N1)pdm09 viruses co-circulated during the season.MethodsPractitioners systematically selected ILI patients to swab within eight days of symptom onset.We compared cases (ILI positive to influenza A(H3N2) or A(H1N1)pdm09) to influenza negative patients. We calculated VE for the two influenza A subtypes and adjusted for potential confounders. We calculated heterogeneity between sites using the I2 index and Cochrane's Q test. If the I2 was <50%, we estimated pooled VE as (1 minus the OR) × 100 using a one-stage model with study site as a fixed effect. If the I2 was >49% we used a two-stage random effects model.ResultsWe included in the A(H1N1)pdm09 analysis 531 cases and 1712 controls and in the A(H3N2) analysis 623 cases and 1920 controls. For A(H1N1)pdm09, the Q test (p = 0.695) and the I2 index (0%) suggested no heterogeneity of adjusted VE between study sites. Using a one-stage model, the overall pooled adjusted VE against influenza A(H1N1)pdm2009 was 47.5% (95% CI: 16.4–67.0).For A(H3N2), the I2 was 51.5% (p = 0.067). Using a two-stage model for the pooled analysis, the adjusted VE against A(H3N2) was 29.7 (95% CI: −34.4–63.2).ConclusionsThe results suggest a moderate 2013–2014 influenza VE against A(H1N1)pdm09 and a low VE against A(H3N2). The A(H3N2) estimates were heterogeneous among study sites. Larger sample sizes by study site are needed to prevent statistical heterogeneity, decrease variability and allow for two-stage pooled VE for all subgroup analyses.  相似文献   
44.
《Vaccine》2015,33(28):3200-3207
PurposeIn April 2007, Panama introduced Hepatitis A universal vaccination using a two-dose schedule (Havrix® junior; GSK Vaccines, Belgium). We assessed the impact of this hepatitis A vaccine three years after it was recommended for universal mass vaccination in Panama.Materials and methodsHepatitis A vaccination impact was assessed using two different approaches. The first approach used retrospective data (incidence and number of cases for all age groups), collected from the passive surveillance of the Epidemiologic Surveillance System of the Ministry of Health of hepatitis A and unspecified hepatitis before (2000–2006) and after (2008–2010) introduction of hepatitis A vaccine. The second approach was a prospective hospital-based active surveillance for hepatitis cases conducted in subjects (0–14years) during 2009–2011 at three sentinel hospitals in Panama.ResultsOverall, the annual incidence of hepatitis A and unspecified hepatitis in 2008, 2009 and 2010 were 13.1, 7.9 and 3.7 per 100,000 subjects, lower than the baseline incidence of 51.1 per 100,000 subjects. In comparison to the mean baseline period (2000–2006), there was an 82% mean reduction in the overall hepatitis-related outcomes (hepatitis A and unspecified hepatitis) after vaccine introduction (2008–2010) in all age groups.In the hospital-based surveillance (2009–2011), of the 42 probable viral hepatitis A cases, nine cases were confirmed as acute hepatitis A (8 in 2009, 1 in 2010). Of these confirmed cases, two belonged to the targeted vaccine group (1–4 years) but were not vaccinated.ConclusionsOur study suggests that the introduction of two-dose hepatitis A vaccines in Panama has contributed to the reduction in the incidence of overall hepatitis-related outcomes for all age groups, suggesting herd protection. Additional monitoring is required to document a sustained long-term effect.  相似文献   
45.
Clonal hematopoiesis (CH)—an expansion of blood cells derived from a single hematopoietic stem cell—is a defining feature of hematologic cancers, but recently CH was also found to be a frequent consequence of aging. When aging-associated CH results from acquisition of a somatic mutation in a driver gene associated with leukemia, and this mutation is present at a variant allele frequency of at least 0.02 (2%) yet the patient does not meet World Health Organization diagnostic criteria for a hematologic neoplasm, this state is termed clonal hematopoiesis of indeterminate potential (CHIP). CHIP is present in approximately 10% to 15% of people older than 70 years and more than 30% by age 85 years and represents a precursor state for neoplasia akin to monoclonal gammopathy of undetermined significance. Recently, CHIP was unexpectedly found to be an important risk factor for cardiovascular events, with accumulating evidence supporting a mechanism of accelerated atherogenesis as a result of vascular inflammation driven by clonally derived monocytes/macrophages. Risk factors for CHIP include aging, male sex, cigarette smoking, and a common germline variant in the telomere-associated gene TERT. Clonal hematopoiesis can also occur after cytotoxic chemotherapy or radiotherapy for a solid tumor, after hematopoietic stem cell transplant, in the context of aplastic anemia, or after induction chemotherapy for acute leukemia; in each setting, CH has distinct clinical implications. This review summarizes recent studies of CH and CHIP and outlines challenges in clinical management of affected patients.  相似文献   
46.

Background

Obesity as one of the risk factors for cardiovascular diseases increases mortality in general population. Several clinical studies investigated clinical outcomes in patients with different body mass index (BMI) after cardiac arrest (CA). Controversial data regarding BMI on clinical outcomes in those patients exist in those studies. Therefore, we conducted a meta-analysis to evaluate the effect of BMI on survival condition and neurological prognosis in those patients.

Methods

We searched Pubmed, Embase, Ovid/Medline and EBM reviews databases for relational studies investigating the association between BMI and clinical outcomes of patients after CA. Seven studies involving 25,035 patients were included in this meta-analysis. Primary outcome was survival condition and secondary outcome was neurological prognosis. Three comparisons were conducted: underweight (BMI < 18.5) versus normal weight (18.5  BMI < 25), overweight (25  BMI < 30) versus normal weight and obese (BMI  30) versus normal weight.

Results

Using normal weight patients as reference, underweight patients had a higher mortality (odds ratio [OR] 1.35; 95% confidence interval [CI] 1.10 to 1.66; P = 0.004; I2 = 17%). Overweight was associated with increased hospital survival (OR 0.80; 95% CI 0.65 to 0.98; P = 0.03; I2 = 62%) and better neurological recovery (OR 0.72; 95% CI 0.61 to 0.85; P < 0.001; I2 = 0%). No significant difference was found in clinical outcomes between obese and normal weight patients.

Conclusions

Low BMI was associated with lower survival rate in CA patients. Overweight was associated with a higher survival rate and better neurological recovery. Clinical outcomes did not differ between obese and normal weight patients. Further studies are needed to explore the underlying mechanisms.  相似文献   
47.
Many trace elements are considered essential [iron (Fe), zinc (Zn), copper (Cu)], whereas others may be harmful [lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As)], depending on their concentration and chemical form. In most cases, the diet is the main pathway by which they enter our organism. The presence of toxic trace elements in food has been known for a long time, and many of the food matrices that carry them have been identified. This has led to the appearance of legislation and recommendations concerning consumption. Given that the main route of exposure is oral, passage through the gastrointestinal tract plays a fundamental role in their entry into the organism, where they exert their toxic effect. Although the digestive system can be considered to be of crucial importance in their toxicity, in most cases we do not know the events that occur during the passage of these elements through the gastrointestinal tract and of ascertaining whether they may have some kind of toxic effect on it. The aim of this review is to summarize available information on this subject, concentrating on the toxic trace elements that are of greatest interest for organizations concerned with food safety and health: Pb, Cd, Hg and As.  相似文献   
48.
Mycotoxins are secondary metabolites produced by fungi contaminating the food chain that are toxic to animals and humans. Children up to 12 years old are recognized as a potentially vulnerable subgroup with respect to consumption of these contaminants. Apart from having a higher exposure per kg body weight, they have a different physiology from that of adults. Therefore they may be more sensitive to neurotoxic, endocrine and immunological effects. For these reasons, a specific and up-to-date risk analysis for this category is of great interest.In this review, an accurate analysis of the main mycotoxins occurring in food intended for children (deoxynivalenol, aflatoxins, ochratoxins, patulin and fumonisins) is presented. In particular, known mechanisms of toxicity and levels of exposure and bioaccessibility in children are shown. In addition, recent discoveries about the strategies of mycotoxins managing are discussed.  相似文献   
49.
The silicate mineral asbestos is categorized into two main groups based on fiber structure: serpentine asbestos (chrysotile) and amphibole asbestos (crocidolite, amosite, anthophyllite, tremolite, and actinolite). Chrysotile is used in more than 2 000 applications and is especially prevalent in the construction industry. Although its use is banned or restricted in more than 52 countries, an estimated 107 000 workers die from asbestos exposure each year, and approximately 125 million workers continue to be exposed. Furthermore, ambient exposures persist to which the public is exposed, globally. Today, the primary controversies regarding the use of asbestos are the potencies of different types of asbestos, as opposed whether or not asbestos causes morbidity and mortality. The asbestos industry has promoted and funded research based on selected literature, ignoring both clinical and scientific knowledge. In this piece, we highlight a prominent example of a conflicted publication that sought to undermine the World Health Organization (WHO) campaign to stop the use of all forms of asbestos, including chrysotile asbestos. Independent and rigorous scientific data provide sufficient evidence that chrysotile asbestos, like other forms of asbestos, is a cause of asbestos-related morbidity and premature mortality  相似文献   
50.
Myelodysplastic syndromes (MDS) are clonal haematopoietic stem cell disorders characterised by ineffective and dyspoietic haematopoiesis. The natural history of these disorders is variable and ranges from a chronic to a rapid course towards leukaemic progression. Certain shortcomings have been encountered in the French-American-British (FAB) classification over the years, and therefore there is a need for an alternative method of classification. In 1999, the WHO published a revised classification of MDS. In the present study, we have analysed the clinical, haematological and histomorphological features in 96 cases of primary MDS seen in the department of haematology at the All India Institute of Medical Sciences (AIIMS) over a 6-yr period (1996-2001). Both FAB and WHO classifications have been incorporated and the Bournemouth scoring system applied in each case at presentation. The Bournemouth scoring system, in the absence of a cytogenetic study, offers a good prognostication and long-term survival estimate.  相似文献   
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