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981.
Parasitology Research - Pathogenic bacteria share their natural habitat with many other organisms such as animals, plants, insects, parasites and amoeba. Interactions between these organisms...  相似文献   
982.
Porcine bocavirus (PBoV) has a high prevalence in both healthy and diseased swine around the world. It was recently reported that PBoV and porcine circovirus type 2 (PCV2)—which contribute to porcine diarrheal disease—have a high rate of co-infection. To clarify the pathogenesis of PBoV, we examined the co-infection rate and effects of these two pathogens in IPEC-J2 porcine intestinal enterocytes. Both single and co-infection had cytopathic effects in IPEC-J2 cells. The apoptosis and proliferation rates of cells infected with both viruses did not differ significantly from those of cells infected with either one alone. PBoV and PCV2 induced the upregulation of inflammatory cytokines and the downregulation of the tight junction proteins occludin and claudin 1 in the early stage of infection, leading to destruction of epithelial barrier integrity and enhanced cytotoxicity. These findings provide insight into the pathogenic mechanisms of PBoV and PCV2 and a basis for developing effective strategies to prevent the spread of gastrointestinal diseases in pigs and other livestock.  相似文献   
983.
984.
A ventricular septal defect is the most common congenital cardiac abnormality encountered in infants and children. Many of them survive through adulthood before diagnosis. Two‐thirds of the cases involve the membranous part of the septum. In the absence of an interventricular shunt or concomitant cardiac surgery, guidelines for surgical intervention or resection of isolated aneurysms of the membranous septum are not well established. In this report, we discuss a multi–imaging modality approach for the diagnosis and assessment of membranous ventricular septal aneurysms and review the experts' consensuses for follow‐up and treatment strategies.  相似文献   
985.
986.
Using the polymerase chain reaction (PCR) assay, we developed a rapid diagnosis method for Salmonella typhi infection in blood specimens from patients with typhoid fever. Primers were designed from the flagellin gene sequence, which would give an amplification product of 367 base pairs. In this study, the specificity of the assay, with no amplification, was seen for the other Salmonella strains with the flagellin gene, and not for non-Salmonella bacteria. For the sensitivity test, the protocol described allowed the detection of two to three copies of the Salmonella typhi genome, as determined by serial dilution of genomic DNA from Salmonella typhi. With the PCR technique, genomic DNA of Salmonella typhi was detected in 46 of 73 blood samples collected from patients with clinically suspected typhoid fever who had fever within 3 days of admission to the General Hospital, Makassar, South Sulawesi, Indonesia, and who had had no prior antibiotic treatment. The PCR results (63% positive cases) were compared with those of blood culture (13.7% positive cases) and the Widal test (35.6% positive cases), using the same samples from each of the 73 patients admitted to the General Hospital in Makassar. The time taken for PCR analysis of each sample was less than 12h, compared with 3 to 5 days for blood or clot culture. The PCR with one pair of primers can be used as a novel, rapid diagnotic method for typhoid fever, particularly when results of standard culture assays are negative.  相似文献   
987.
OBJECTIVE: To study the effectiveness and side effects of polyarticular corticosteroid injection compared to systemic administration in patients with rheumatoid arthritis (RA), and to examine the differential response to injection among joints. METHODS: Sixty-nine RA patients presenting with 6-12 swollen joints were enrolled to participate in a randomized trial consisting of polyarticular injection in 6-8 swollen joints of intraarticular (IA) triamcinolone hexacetonide (IA group) or intramuscular (IM) mini-pulse therapy with triamcinolone acetonide in equivalent doses (IM group). Blind examination at baseline (T0), Weeks 1 (T1), 4 (T4), 12 (T12), and 24 (T24) postintervention included American College of Rheumatology improvement criteria ACR20%, 50% and 70%, visual analog scale for articular pain, pain on movement, joint count, range of motion, morning stiffness, quality of life (Medical Outcome Study Short Form-36), use of nonsteroidal antiinflammatory drugs and oral corticosteroid, blood pressure, adverse effects, calls to the physician, and hospital visits. RESULTS: Significantly better results were observed for IA compared to IM patients as follows: ACR20% (61.7% vs 28.5% at T1; 73.5% vs 42.8% at T4), ACR50% (29.4% vs 5.7% at T1; 44.1% vs 20% at T4), ACR70% (11.7% vs 0% at T1), patient's evaluation of disease activity, lower tender joint count, lower blood pressure, lower number of adverse effects, calls to the physician, and hospital visits (p < 0.05). Less significant adrenocorticotropic hormone reduction was observed for IA group at T4 and T12 (p < 0.05). Elbows and metacarpophalangeal joints had the best response to corticosteroid injection. CONCLUSION: In the short term, polyarticular IA injection was better than IM corticosteroid, as shown by ACR improvement criteria and number of adverse effects.  相似文献   
988.
Dubin-Johnson syndrome with systemic lupus erythematosus: a case report   总被引:3,自引:0,他引:3  
Introduction Dubin-Johnson syndrome (DJS) is a rare recessively inherited conjugated hyperbilirubi- nemia caused by deficiency of the canalicular multi-drug resistance/multi-specific organic anionic transporter protein (MDR2/cMOAT). Thus bilirubin is conjugated but inefficiently secreted into bile, which results in accumulation of conjugated and, to some extent, unconjugated bilirubin in blood, leading to hyperbilirubinemia and bilirubinuria. But, the results of liver function tests are no…  相似文献   
989.

BACKGROUND:

Dihydropyridine calcium channel blockers are widely used for the treatment of hypertension and angina. Despite safety concerns associated with short-acting agents, increasing evidence supports the safety of long-acting dihydropyridines. Although amlodipine is the best studied of these, there are few studies comparing it with nifedipine.

OBJECTIVE:

To examine the association between hospitalization for acute coronary syndromes and treatment with amlodipine or extended-release nifedipine in patients 65 years of age and older. The primary objective was a composite of hospital admission for angina or acute myocardial infarction.

METHODS:

The present population-based, retrospective cohort study used linked health care databases from Ontario. Propensity scores were used to identify highly similar patients started on amlodipine or extended-release nifedipine between April 1997 and March 2002. Time-to-event analysis was conducted using Cox proportional hazards models.

RESULTS:

The analysis included 24,190 patients (44% male; mean age 75 years) treated with amlodipine or extended-release nifedipine (n=12,095 each). The number of patients reaching the primary end point was 362 (3%) and 294 (2.4%) in the amlodipine and nifedipine groups, respectively. The groups were similar in a large number of demographic and clinical characteristics. No significant differences were observed among users of extended-release nifedipine (adjusted hazard ratio 0.91, 95% CI 0.74 to 1.13) relative to amlodipine.

CONCLUSIONS:

These findings suggest that amlodipine and extended-release nifedipine are not associated with differential rates of acute coronary events in older patients.  相似文献   
990.
Bone marrow mesenchymal stem cells (MSCs) participate in myocardial repair following myocardial infarction. However, their in vivo reparative capability is limited due to lack of their survival in the infarcted myocardium. To overcome this limitation, we genetically engineered male rat MSCs overexpressing CXCR4 in order to maximize the effect of stromal cell-derived factor-1α (SDF-1α) for cell migration and regeneration. MSCs were isolated from adult male rats and cultured. Adenoviral transduction was carried out to over-express either CXCR4/green fluorescent protein (Ad-CXCR4/GFP) or Ad-null/GFP alone (control). Flow cytometry was used to identify and isolate GFP/CXCR4 over-expressing MSCs for transplantation. Female rats were assigned to one of four groups (n = 8 each) to receive GFP-transduced male MSCs (2 × 106) via tail vein injection 3 days after ligation of the left anterior descending (LAD) coronary artery: GFP-transduced MSCs (Ad-null/GFP-MSCs, group 1) or MSCs over-expressing CXCR4/GFP (Ad-CXCR4/GFP-MSCs, group 2), or Ad-CXCR4/GFP-MSCs plus SDF-1α (50 ng/μl) (Ad-CXCR4/GFP-MSCs/SDF-1α, group 3), or Ad-miRNA targeting CXCR4 plus SDF-1α (Ad-miRNA/GFP-MSCs + SDF-1α treatment, group 4). Cardiodynamic data were obtained 4 weeks after induction of regional myocardial infarction (MI) using echocardiography after which hearts were harvested for immunohistochemical studies. The migration of GFP and Y-chromosome positive cells increased significantly in the peri- and infarct areas of groups 2 and 3 compared to control group (p < 0.05), or miRNA-CXCR4 group (p < 0.01). The number of CXCR4 positive cells in groups 2, 3 was intimately associated with angiogenesis and myogenesis. MSCs engraftment was blocked by pretreatment with miRNA (group 4). Cardiac function was significantly improved in rats receiving MSCs over-expressing CXCR4 alone or with SDF-1α. The up-regulation of matrix metalloproteinases (MMPs) by CXCR4 overexpressing MSCs perhaps facilitated their engraftment in the collagenous tissue of the infarcted area. CXCR4 over-expression led to enhance in vivo mobilization and engraftment of MSCs into ischemic area where these cells promoted neomyoangiogenesis and alleviated early signs of left ventricular remodeling.  相似文献   
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