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941.
Accruing data strongly support the possible role of CD8+ T cells in immunity against tuberculosis (TB). Multivalent vaccines against Mycobacterium tuberculosis (Mtb) that incorporate CD8+ T cell antigens with those that elicit CD4+ T cells are therefore highly desirable. To screen for potential CD8+ T cell antigens that are produced by Mtb during infection, we isolated pathogen-derived peptides that bound to MHC Class I molecules expressed in adherent splenocytes obtained from Mtb-infected mice. Mass spectroscopy analysis revealed the following four nonamer peptides that had 100% homology with Mtb proteins: DGYVGAPAH (MT_0401), TTMPLFAD (MT_1164), RSGAATPVR (MT_2160.1) and LAAVVGVVL (MT_0078). The gene MT_0401 codes the protein 5′-phosphoribosylglycinamide transformylase 2 and the other three genes code for hypothetical proteins with unknown function. The NCBI/Blast analysis showed that among the four peptides DGYVGAPAH had the highest maximum alignment score and lowest E value (number of alignments expected by chance). Therefore, we assessed whether MT_0401 expressed in two genetic vaccine formulations was capable of stimulating CD8+ T cell response that is specific to DGYVGAPAH peptide. When mice were immunized with a recombinant plasmid DNA and an E1/E3-deleted Adenovirus 5 expressing MT0401 protein, using both homologous and heterologous prime-boost protocols, they developed strong DGYVGAPAH-specific CD8+ T cell response as well as antibody and CD4+ specific T cell response to the full length MT0401 protein. Equally important was the observation that mice infected with Mtb developed DGYVGAPAH-specific CD8+ T cell responses in both spleen and lungs. These results demonstrate that Mtb antigens that are processed and presented via MHC Class I machinery can be readily identified by the described approach and may be useful candidate antigens to stimulate specific CD8+ T cell responses in vaccine development programs.  相似文献   
942.

Background

Streptococcus pneumoniae is a leading cause of hospitalization in HIV-infected adults therefore pneumococcal vaccine is recommended. The ideal antipneumococcal vaccine and effective vaccination regimen remain controversial and needs further evaluation.

Methods

To assess the efficacy of pneumococcal vaccines alone and combined, a randomized, blinded clinical trial was conducted in Brazil with 331 HIV-patients aged 18–60, with CD4-T cell count ≥200 cells/mm3. Two interventions 60 days apart were done in three schedules: 23-valent pneumococcal polysaccharide vaccine (PPV23)/placebo; 7-valent pneumococcal conjugate vaccine (PCV7)/placebo; and PCV7 plus PPV23. Safety and reactogenicity were evaluated, and immunogenicity was assessed by an IgG enzyme-linked immunosorbent assay to S. pneumoniae serotypes 6B, 9V and 14, performed at baseline, 60 and 180 days after first intervention. Comparison of immunogenicity was based on geometric mean concentration (GMC), percentages of individuals with serotype-specific IgG ≥ 0.35 μg/mL and ≥1.0 μg/mL and proportion of individuals with ≥4-fold increase in specific antibody concentrations for each serotype.

Results

Demographic and HIV conditions were similar, and both vaccines were well tolerated across vaccine groups. Significant increase in IgG-antibodies was observed to all serotypes evaluated. A greater proportion of PCV7 recipients reached and sustained IgG antibody concentrations at least four times as high as those at baseline, for serotypes 6B and 9V. A PPV23 dose after PCV7 did not enhance immunogenicity.

Conclusions

In this first trial conducted with HIV-infected immunologically stable adults in South America, both PPV23 and PCV7 were safe and immunogenic. Evidence suggesting PCV7 was more immunogenic than PPV23, as it elicited higher and persistent ≥4-fold increase of antibodies for 6B and 9V serotypes in a greater proportion of HIV-patients is noteworthy. Despite current recommendation of schedules combining PCV7 and PPV23, there is little evidence to support this practice and we did not observe benefits in this combination.  相似文献   
943.
Obstetric vesicovaginal fistula is nowadays rare in developed countries. We are reporting two cases of patients with obstetric vesicovaginal fistula that occurred after operative vaginal deliveries performed in a French hospital. Early postpartum symptoms were vaginal urine leakage and infectious syndrome. The fistula has been cured by vaginal surgery one case and combined (laparotomy and vagina surgery) in the other case. Patients were totally healed a few months following the surgery.  相似文献   
944.
Clinical Rheumatology - Influenza A (H3N2) virus is the major cause of morbidity/mortality due to seasonal influenza over 50 years. Data about the safety/immunogenicity of influenza...  相似文献   
945.

Problem

The Brazilian population lacks equitable access to specialized health care and diagnostic tests, especially in remote municipalities, where health professionals often feel isolated and staff turnover is high. Telehealth has the potential to improve patients’ access to specialized health care, but little is known about it in terms of cost-effectiveness, access to services or user satisfaction.

Approach

In 2005, the State Government of Minas Gerais, Brazil, funded the establishment of the Telehealth Network, intended to connect university hospitals with the state’s remote municipal health departments; support professionals in providing tele-assistance; and perform tele-electrocardiography and teleconsultations. The network uses low-cost equipment and has employed various strategies to overcome the barriers to telehealth use.

Local setting

The Telehealth Network connects specialists in state university hospitals with primary health-care professionals in 608 municipalities of the large state of Minas Gerais, many of them in remote areas.

Relevant changes

From June 2006 to October 2011, 782 773 electrocardiograms and 30 883 teleconsultations were performed through the network, and 6000 health professionals were trained in its use. Most of these professionals (97%) were satisfied with the system, which was cost-effective, economically viable and averted 81% of potential case referrals to distant centres.

Lessons learnt

To succeed, a telehealth service must be part of a collaborative network, meet the real needs of local health professionals, use simple technology and have at least some face-to-face components. If applied to health problems for which care is in high demand, this type of service can be economically viable and can help to improve patient access to specialized health care.  相似文献   
946.
Concern over the harmful effects of drug use by the elderly has motivated studies aimed at identifying problems in such utilization. This was a household survey with retirees aged > 60 years living in Belo Horizonte, Minas Gerais State, Brazil, in 2003, who reported having a diagnosis of diabetes and/or hypertension. Quality of anti-hypertensive and anti-diabetic medication was measured by redundancy, combinations of drugs, and inappropriate drugs. Among 283 elderly patients (89%) with self-reported hypertension and use of anti-hypertensive pharmacotherapy, 68.2% were using diuretics and 37.8% ACE inhibitors. Among the 22 (64.7%) self-reported diabetic patients under pharmacotherapy, 45.5% were using insulin and 77.3% oral anti-diabetic agents. Among the 89 self-reported diabetic and hypertensive patients, 80 (90%) were using anti-hypertensive drugs and 51 (57.3%) anti-diabetic agents. The study revealed the use of dose combinations, redundant use, and inappropriate medicines, thus indicating the need to monitor treatment protocols and improve healthcare for elderly patients.  相似文献   
947.
In order to describe accidents at work at a hospital in Northern Portugal and analyze their main impact in the period from 2008 to 2010, we conducted a retrospective cross-sectional study. The information was obtained from the notification records of accidents at work for 387 workers. The highest prevalence levels of accidents referred to superior health technician (56.1%), female workers (81.9%), in the age group 30-39 years (37.2%), with a secondary education degree (55.8%), working in shifts (72.4%) and in-patient services (35.9%). Needle pricks were the main cause (45.7%) and hands were the main injury location (37.5%). Wounds (32.6%) were the most frequent type of injury, followed by sprains and strains (23%). In total, 27.4% resulted in absence from work, with sprains and strains as the main reason. Preventive strategies should be adopted, aiming to promote these workers' health.  相似文献   
948.
Melanoma is the most aggressive skin cancer type. It is characterized by pigmented lesions with high tissue invasion and metastatic potential. The early detection of melanoma is extremely important to improve patient prognosis and survival rate, since it can progress to the deadly metastatic stage. Presently, the melanoma diagnosis is based on the clinical analysis of the macroscopic lesion characteristics such as shape, color, borders following the ABCD rules. The aim of this study is to evaluate the time-resolved fluorescence lifetime of NADH and FAD molecules to detect cutaneous melanoma in an experimental in vivo model. Forty-two lesions were analyzed and the data was classified using linear discriminant analysis, a sensitivity of 99.4%, specificity of 97.4% and accuracy of 98.4% were achieved. These results show the potential of this fluorescence spectroscopy for melanoma detection.OCIS codes: (300.6500) Spectroscopy, time-resolved; (170.3650) Lifetime-based sensing; (170.3890) Medical optics instrumentation; (170.6510) Spectroscopy, tissue diagnostics; (170.6935) Tissue characterization  相似文献   
949.
950.
The objective of this study was to evaluate the bacteriological quality of raw cow's milk utilized for the production of Traditional Minas Serro cheese, a Brazilian farmstead raw milk cheese. Raw milk samples were collected from six farmstead cheese operations manufacturing raw milk cheese from cow's milk. Coliform count (CC) and Escherichia coli counts were determined using Petrifilm? EC plates, and Staphylococcus aureus counts were determined using Petrifilm? Staph Express count plates. The standard plate count (SPC) was determined using plate count agar. The somatic cell count (SCC) was determined with a DeLaval cell counter. The detection of Listeria monocytogenes was based in the ISO 11290-1 protocol. A total of 165 samples were analyzed, and the SPC was 1.85-7.88 log CFU/mL. Coliform were detected in 140 (84.8%) of the 165 samples, with counts of 1-6.39 log CFU/mL. E. coli was detected in 17 (10.3%) samples, with counts of 1-2.18 log CFU/mL. The SCC in raw milk was 10,000-1,390,000 cells per mL, with mean and geometric mean values of 247,000 and 162,181, respectively. The SCC did not differ significantly between the seasons (p>0.05), but differed between different farms (p<0.05). None of the 155 samples were positive for the presence of Listeria monocytogenes. S. aureus was isolated in 145 (94.1%) of the 154 samples, and the count was 1.47-5.03 log CFU/mL. The median of SPC, CC, and S. aureus counts differed significantly between seasons and between farms (p<0.05). Our results indicate that raw milk for production of farmstead raw milk cheese has a low incidence of L. monocytogenes and a high incidence of S. aureus, and suggest that measurements (such as SCC or SPC) may not serve as a predictor of other bacterial (including pathogenic) presence.  相似文献   
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