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991.

Objective

To determine morbidity and costs related to a large measles outbreak in Germany and to identify ways to improve the country’s national measles elimination strategy.

Methods

We investigated a large outbreak of measles in the federal state of North Rhine-Westphalia (NRW) that occurred in 2006 after 2 years of low measles incidence (< 1 case per 100 000). WHO’s clinical case definition was used, and surveillance data from 2006 and 2001 were compared. All cases notified in Duisburg, the most severely affected city, were contacted and interviewed or sent a questionnaire. Health-care provider costs were calculated using information on complications, hospitalization and physician consultations.

Findings

In NRW, 1749 cases were notified over a 48-week period. Compared with 2001, the distribution of cases shifted to older age groups (especially the 10–14 year group). Most cases (n = 614) occurred in Duisburg. Of these, 81% were interviewed; 15% were hospitalized and two died. Of the 464 for whom information was available, 80% were reported as unvaccinated. Common reasons for non-vaccination were parents either forgetting (36%) or rejecting (28%) vaccination. The average cost per measles case was estimated at €373.

Conclusion

An accumulation of non-immune individuals led to this outbreak. The shift in age distribution has implications for the effectiveness of measles control and the elimination strategy in place. Immediate nationwide school-based catch-up vaccination campaigns targeting older age groups are needed to close critical immunity gaps. Otherwise, the elimination of measles in Germany and thus in Europe by 2010 will not be feasible.  相似文献   
992.
Before childhood vaccination was introduced in the 1940s, pertussis was a major cause of infant death worldwide. Widespread vaccination of children succeeded in reducing illness and death. In the 1990s, a resurgence of pertussis was observed in a number of countries with highly vaccinated populations, and pertussis has become the most prevalent vaccine-preventable disease in industrialized countries. We present evidence that in the Netherlands the dramatic increase in pertussis is temporally associated with the emergence of Bordetella pertussis strains carrying a novel allele for the pertussis toxin promoter, which confers increased pertussis toxin (Ptx) production. Epidemiologic data suggest that these strains are more virulent in humans. We discuss changes in the ecology of B. pertussis that may have driven this adaptation. Our results underline the importance of Ptx in transmission, suggest that vaccination may select for increased virulence, and indicate ways to control pertussis more effectively.  相似文献   
993.
Cultured primary porcine urinary bladder epithelial cells (PUBEC) represent an adequate and easy to handle in vitro system for studies of urothelial toxicity. PUBEC maintain in vivo-like metabolic activities and physiological functions. They express inducible cytochrome P4501A isoenzymes, which are of particular relevance, since they contribute to activation of bladder carcinogens. A possible drawback of PUBEC is their isolation from common domestic pigs that do not represent an inbred strain. In order to further establish PUBEC as a standard in vitro toxicity test system we analysed possible interindividual differences in CYP1A1 inducibility. Interestingly, we observed by flow cytometry that PUBEC obtained from individual pigs consist of two distinct subpopulations with inducible and non-inducible cells. A strong, concentration-dependent CYP1A1 induction was observed in the responsive subpopulation when incubated with benzo[a]pyrene (B[a]P) in a concentration range between 1 and 10 μM. In contrast, no CYP1A1 induction was obtained in the non-responsive subpopulation up to the highest tested concentrations of 100 μM. The fraction of responsive cells showed large interindividual differences ranging from 10 to 65% of the total cell number. For practical purposes it might be reasonable to analyse pools of PUBEC from five pigs which substantially reduce batch to batch variability. In conclusion, we have identified two functionally distinct subpopulations of urinary bladder epithelial cells. It will be interesting to study whether the CYP1A inducible subtype is more susceptible to bladder carcinogens. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
994.
995.
BACKGROUND: Apheresis technology has made tremendous progress up to the development of automated blood component collection, which offers increased efficiency in donor blood use, but the concern about the contact of donor blood with artificial surfaces remains. Activation of the hemostatic system is a major issue in this context and is controversial. The aim of this study was to estimate the effect of apheresis on continuous thrombin generation (TG), representing a new tool to examine the overall function of the plasmatic clotting system. STUDY DESIGN AND METHODS: Twenty-six voluntary blood donors, fulfilling the law requirement for apheresis donation, participated in the study. Two units of platelets (6 x 10(11)) and 1 unit of red cells (250 mL; hematocrit level, 80%) were collected using two types of cell separators (Amicus, Fenwal, Inc.; and Trima Accel, Gambro BCT). Each donor underwent collection on both apheresis systems with at least 8 weeks in between. Samples of blood were collected before, immediately after, and 48 hours after apheresis. TG was measured using a slow fluorogenic substrate by means of calibrated automated thrombography (CAT). RESULTS: CAT data changed only slightly, and no significant changes were seen before, immediately after, and 48 hours after apheresis (p > 0.05). The variables did not differ significantly between the two different apheresis systems (p > 0.05). CONCLUSION: Using a CAT-based technique, no change in variables of continuous TG were observed, suggesting that multicomponent blood collection did not lead to severe alterations in the hemostatic system of the donors.  相似文献   
996.
The hydroxyanilide fenhexamid, one of the latest antibotrytis fungicides, active especially against leotiomycete plant-pathogenic fungi, inhibits 3-ketoreductase of the C-4-demethylation enzyme complex during ergosterol biosynthesis. We isolated Botrytis cinerea strains resistant to various levels of fenhexamid from French and German vineyards. The sequence of the gene encoding 3-ketoreductase, erg27, varied according to levels of resistance. Highly resistant isolates, termed HydR3(+), all presented a modification of the phenylalanine at the C terminus of the putative transmembrane domain at position 412, either to serine (85% of the isolates), to isoleucine (11.5% of the isolates), or to valine (3.5% of the isolates). The introduction of the erg27(HydR3(+)) allele into a fenhexamid-sensitive strain by means of a replicative plasmid conferred fenhexamid resistance on the resulting transformants, showing that the mutations at position 412 are responsible for fenhexamid resistance. Weakly to moderately resistant isolates, termed HydR3(-), showed different point mutations between the strains in the sequenced regions of the erg27 gene, corresponding to amino acid changes between positions 195 and 400 of the protein. The erg27(HydR3(-)) alleles on the replicative vector introduced into a sensitive strain did not confer resistance to fenhexamid. Genetic crosses between HydR3(-) and sensitive strains showed strict correlation between the sequenced mutation in the erg27 gene and the resistance phenotypes, suggesting that these mutations are linked to fenhexamid resistance. The HydR3 mutations possibly modify the affinity of the 3-ketoreductase enzyme for its specific inhibitor, fenhexamid.  相似文献   
997.
OBJECTIVE— In type 1 diabetes, plantar fascia, a collagen-rich tissue, is susceptible to glycation and oxidation. Paraoxonase-1 (PON1) is an HDL-bound antioxidant enzyme. PON1 polymorphisms have been associated with susceptibility to macro- and microvascular complications. We investigated the relationship between plantar fascia thickness (PFT) and PON1 gene variants, p.Leu54Met, p.Gln192Arg, and c.-107C>T, in type 1 diabetes.RESEARCH DESIGN AND METHODS—This was a cross-sectional study of 331 adolescents with type 1 diabetes (162 male and 169 female). PFT was assessed by ultrasound, PON1 was assessed by genotyping with PCR and restriction fragment–length polymorphism, and serum PON1 activity was assessed by rates of hydrolysis of paraoxon and phenylacetate.RESULTS—Median (interquartile range) age was 15.4 (13.5–17.3) years, and diabetes duration was 7.6 (4.9–10.6) years. The distribution of p.Leu54Met genotypes was LL 135 (40.8%), ML 149 (45%), and MM 47 (14.2%). PFT was abnormal (>1.7 mm) in 159 adolescents (48%). In multivariate analysis, predictors of abnormal PFT were ML/LL versus MM p.Leu54Met polymorphism (odds ratio 3.84 [95% CI 1.49–9.82], P = 0.005); BMI (percentile) (1.02 [1.01–1.03], P = 0.007); systolic blood pressure (percentile) (1.01 [1.00–1.02], P = 0.03); and male sex (3.29 [1.98–5.46], P < 0.001).CONCLUSIONS—Thickening of the plantar aponeurosis occurs predominantly in overweight and male adolescents with type 1 diabetes. The MM genotype at PON1 p.Leu54Met is associated with a reduced risk of abnormal PFT.Paraoxonase-1 (PON1) is a calcium-dependent HDL-associated enzyme that protects LDLs from oxidation. In type 1 diabetic patients, the serum paraoxonase concentration is lower and HDL is a less efficient antioxidant than in healthy individuals (1). Oxidized LDL is implicated in the pathogenesis of atherosclerosis, diabetic retinopathy, and nephropathy (2). Variations in lipoprotein-related enzymes and genotypes may also promote diabetic microvascular damage (3).Soft-tissue thickening is associated with chronic hyperglycemia and is hypothesized to be due to collagen glycation (4). With use of ultrasound techniques to measure plantar aponeurosis, a collagen-rich tissue, researchers demonstrated previously that people with diabetes have increased plantar fascia thickness (PFT) (5). Recently, this group reported that increased PFT predicted the development of microvascular complications in adolescents with type 1 diabetes and proposed abnormal PFT as a putative marker of soft-tissue glycation (6).The PON gene cluster maps to chromosome 7q21-22 and influences gene expression and serum activity. There is an established link between PON1 and macrovascular disease (7) and emerging evidence linking PON1 to microvascular complications (8,9). In this study we investigated whether the variants c.-107C>T at the promoter region and p.Leu54Met and p.Gln192Arg at the coding regions of PON1 are associated with PFT in type 1 diabetes.  相似文献   
998.
999.
1000.
BACKGROUND: Amyloid-beta (Abeta) plaque formation is a hallmark of Alzheimer's disease (AD) and precedes the onset of dementia. Abeta imaging should allow earlier diagnosis, but clinical application is hindered by the short decay half-life of current Abeta-specific ligands. (18)F-BAY94-9172 is an Abeta ligand that, due to the half-life of (18)F, is suitable for clinical use. We thus studied the effectiveness of this ligand in identifying patients with AD. METHODS: 15 patients with mild AD, 15 healthy elderly controls, and five individuals with frontotemporal lobar degeneration (FTLD) were studied. (18)F-BAY94-9172 binding was quantified by use of the standardised uptake value ratio (SUVR), which was calculated for the neocortex by use of the cerebellum as reference region. SUVR images were visually rated as normal or AD. FINDINGS: (18)F-BAY94-9172 binding matched the reported post-mortem distribution of Abeta plaques. All AD patients showed widespread neocortical binding, which was greater in the precuneus/posterior cingulate and frontal cortex than in the lateral temporal and parietal cortex. There was relative sparing of sensorimotor, occipital, and medial temporal cortex. Healthy controls and FTLD patients showed only white-matter binding, although three controls and one FTLD patient had mild uptake in frontal and precuneus cortex. At 90-120 min after injection, higher neocortical SUVR was observed in AD patients (2.0 [SD 0.3]) than in healthy controls (1.3 [SD 0.2]; p<0.0001) or FTLD patients (1.2 [SD 0.2]; p=0.009). Visual interpretation was 100% sensitive and 90% specific for detection of AD. INTERPRETATION: (18)F-BAY94-9172 PET discriminates between AD and FTLD or healthy controls and might facilitate integration of Abeta imaging into clinical practice.  相似文献   
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