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81.
Mycobacterium tuberculosis rapidly reduces nitrate, leading to the accumulation of nitrite. This characteristic served for the past 40 years to differentiate M. tuberculosis from other members of the Mycobacterium tuberculosis complex (MTBC), such as Mycobacterium bovis (non-BCG [referred to here as simply "M. bovis"]), Mycobacterium bovis BCG, Mycobacterium africanum, or Mycobacterium microti. Here, a narG deletion in M. tuberculosis showed that rapid nitrite accumulation of M. tuberculosis is mediated by narGHJI. Analysis of narG mutants of M. bovis and M. bovis BCG showed that, as in M. tuberculosis, nitrite accumulation was mediated by narGHJI, and no other nitrate reductase was involved. However, in contrast to M. tuberculosis, accumulation was delayed for several days. Comparison of the narGHJI promoter revealed that, at nucleotide -215 prior to the start codon of narG, M. tuberculosis carried a thymine residue, whereas the bovine mycobacteria carried a cytosine residue. Using LightCycler technology we examined 62 strains of M. tuberculosis, M. bovis, M. bovis BCG, M. microti, and M. africanum and demonstrated that this single nucleotide polymorphism was specific for M. tuberculosis. For further differentiation within the MTBC, we included, by using LightCycler technology, the previously described analysis of oxyR polymorphism, which is specific for the bovine mycobacteria, and the RD1 polymorphism, which is specific for M. bovis BCG. Based on these results, we suggest a LightCycler format for rapid and unambiguous diagnosis of M. tuberculosis, M. bovis, and M. bovis BCG.  相似文献   
82.
A major challenge in reconstructive surgery is flap ischemia, which might benefit from induction of therapeutic angiogenesis. Here we demonstrate the effect of an adeno-associated virus (AAV) vector delivering vascular endothelial growth factor (VEGF)165 in two widely recognized in vivo flap models. For the epigastric flap model, animals were injected subcutaneously with 1.5 x 10(11) particles of AAV-VEGF at day 0, 7, or 14 before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF was injected intramuscularly. The delivery of AAV-VEGF significantly improved flap survival in both models, reducing necrosis in all treatment groups compared to controls. The most notable results were obtained by administering the vector 14 days before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF reduced the necrotic area by >50% at 1 week after surgery, with a highly significant improvement in the healing process throughout the following 2 weeks. The therapeutic effect of AAV-VEGF on flap survival was confirmed by histological evidence of neoangiogenesis in the formation of large numbers of CD31-positive capillaries and alpha-smooth muscle actin-positive arteriolae, particularly evident at the border between viable and necrotic tissue. These results underscore the efficacy of VEGF-induced neovascularization for the prevention of tissue ischemia and the improvement of flap survival in reconstructive surgery.  相似文献   
83.
Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals.  相似文献   
84.
In an attempt to clarify how cells integrate the signals provided by multiple chemokines expressed during inflammation, we have uncovered a novel mechanism regulating leukocyte trafficking. Our data indicate that the concomitant exposure to CCR4 agonists and CXCL10/IP-10 strongly enhances the chemotactic response of human T lymphocytes. This enhancement is synergistic rather than additive and occurs via CCR4 since it persists after CXCR3 blockade. Besides chemotaxis, other cellular responses are enhanced upon stimulation of CCR4-transfected cells with CCL22/MDC plus CXCL10. Several other chemokines in addition to CXCL10 were able to increase CCL22-mediated chemotaxis. The first beta-strand of the chemokine structure is highly and specifically implicated in this phenomenon, as established using synergy-inducing and non-synergy-inducing chimeric chemokines. As shown in situ for skin from atopic and allergic contact dermatitis patients, this organ becomes the ideal environment in which skin-homing CCR4(+) T lymphocytes can accumulate under the stimulus offered by CCR4 agonists, together with the synergistic chemokines that are concomitantly expressed. Overall, our results indicate that chemokine-induced synergism strengthens leukocyte recruitment towards tissues co-expressing several chemokines.  相似文献   
85.
86.
Aicardi syndrome (AIC) is a rare congenital neurodevelopmental disorder of unknown etiology, that affects almost exclusively females, originally characterized by corpus callosum agenesis, chorioretinal lacunae, and infantile spasms. The current diagnostic criteria also include qualitative facial features (prominent premaxilla, upturned nasal tip, decreased nasal bridge angle, sparse lateral eyebrows, and microphthalmia) that still need quantification. A three‐dimensional (3D) photogrammetric assessment of 11 Italian females, age 7–32 years, who satisfied AIC criteria, was performed. Linear distances and angles were computed from soft‐tissue facial landmarks coordinates. The z‐score values were calculated using data of 850 healthy reference females matched for age and compared by Mann–Whitney test (p < .01). Patients showed a shorter philtrum and right side orbital height (mean z‐scores: ?1.7, ?0.9), shorter superior, middle, and inferior facial depths (mean z‐scores: ?1.3, ?2.2, ?2.3), and a smaller length of mandibular ramus (mean z‐score: ?2.1); conversely, they showed larger nasal and lower facial widths, and lower facial convexity (mean z‐scores: 1.7, 1.4, 2.4). The inclinations of the orbit versus the true horizontal were increased bilaterally (mean z‐scores: 1.8, 1.1). Some common facial abnormalities were quantified in AIC patients using a noninvasive instrument. They may help clinicians in performing a definite AIC diagnosis in atypical or doubt cases.  相似文献   
87.
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America.  相似文献   
88.
Paracoccidioidomycosis (PCM) is a systemic fungal disease that is particularly important among individuals living and working in rural areas of endemicity in Latin America. Detection of anti-Paracoccidioides brasiliensis antibodies is of limited value due to false-negative results. Detection of P. brasiliensis-gp43 circulating antigen is a practical approach for a specific diagnosis of the disease. In a previous study we described an inhibition enzyme-linked immunosorbent assay able to detect the 43-kDa P. brasiliensis antigen in sera of 100% of patients with the acute form of PCM and in 95.31 and 100% of patients with the chronic multifocal and unifocal forms of PCM. To investigate its potential application for the follow-up of PCM patients during treatment, antigen levels were monitored at regular intervals for up 8 to 12 months in serum samples from 23 patients. The results showed that treatment with itraconazole resulted in decreasing levels of circulating gp43 that were correlated with the reduction of anti-gp43 antibodies. It was also observed that by the end of 12 months of treatment gp43 levels were <5 microg/ml in all patients.  相似文献   
89.
Cellular interaction with the extracellular matrix is thought to be a critical event in controlling angiogenesis and tumor growth. In our previous studies, genetically distinct noncollagenous (NC) domains of type-IV collagen were shown to interact with integrin receptors expressed on the surface of endothelial cells. Moreover, these NC1 domains were shown to inhibit angiogenesis in vivo. Here, we provide evidence that a recombinant form of the alpha2(IV)NC1 domain of type-IV collagen could bind integrins alpha1beta1 and alphavbeta3 expressed on melanoma cells and inhibit tumor cell adhesion in a ligand-specific manner. Systemic administration of recombinant alpha2(IV)NC1 domain potently inhibited M21 melanoma tumor growth within full thickness human skin and exhibited a dose-dependent inhibition of tumor growth in nude mice. Interestingly, alpha2(IV)NC1 domain enhanced cellular senescence in tumor cells in vitro and in vivo. Taken together, these results suggest that recombinant alpha2(IV)NC1 domain is not only a potent anti-angiogenic reagent, but it also directly impacts tumor cell behavior. Thus, alpha2(IV)NC1 domain represents a potent inhibitor of tumor growth by impacting both endothelial and tumor cell compartments.  相似文献   
90.
Traditionally, diagnosis and treatment have been seen as two distinct tasks. Consequently, most approaches to computer supported health care focus on one of the two-mostly on diagnosis or rather on the interpretation of measurements which is much better understood and formalised. However, in practice diagnosis and treatment overlap and influence each other in many ways. Combinations range from repeatedly going through the diagnosis-treatment loop over a period of time to permanent monitoring of the patients' health condition as it is done in intensive care units. In this article we describe how to model these combinations using the clinical protocol-representation language ASBRU. It implements treatment steps in a hierarchy of skeletal, time-oriented plans. Diagnosis can either be described in a declarative way in the conditions, under which treatment steps are taken or it can be modelled explicitly as plans of their own right. We demonstrate our approach using examples taken from the American Association of Paediatricians' guideline for the treatment of hyperbilirubinemia in the new-born.  相似文献   
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