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941.
BACKGROUND: Dens invaginatus is a rare dental anomaly that may give rise to many complex anatomical forms. The complexity of the internal anatomy may create challenges for the complete removal of the diseased pulpal tissue and the subsequent sealing of the canal system. CASE DESCRIPTION: The authors discuss the modification of the internal anatomy under the operating microscope, allowing the clinician better access to treat predictably the canal system with conventional or alternative techniques. CONCLUSION AND CLINICAL IMPLICATIONS: Considering the anatomical variations and the challenges that a dens invaginatus may present, a practitioner may consider a modification of the internal anatomy of the canal system to gain better access for proper instrumentation, disinfection and sealing of the root canal system using conventional or contemporary techniques.  相似文献   
942.
Long-term function of three-dimensional (3D) tissue constructs depends on adequate vascularization after implantation. Accordingly, research in tissue engineering has focused on the analysis of angiogenesis. For this purpose, 2 sophisticated in vivo models (the chorioallantoic membrane and the dorsal skinfold chamber) have recently been introduced in tissue engineering research, allowing a more detailed analysis of angiogenic dysfunction and engraftment failure. To achieve vascularization of tissue constructs, several approaches are currently under investigation. These include the modification of biomaterial properties of scaffolds and the stimulation of blood vessel development and maturation by different growth factors using slow-release devices through pre-encapsulated microspheres. Moreover, new microvascular networks in tissue substitutes can be engineered by using endothelial cells and stem cells or by creating arteriovenous shunt loops. Nonetheless, the currently used techniques are not sufficient to induce the rapid vascularization necessary for an adequate cellular oxygen supply. Thus, future directions of research should focus on the creation of microvascular networks within 3D tissue constructs in vitro before implantation or by co-stimulation of angiogenesis and parenchymal cell proliferation to engineer the vascularized tissue substitute in situ.  相似文献   
943.
A new double-antigen sandwich-based enzyme-linked immunosorbent assay (ELISA) for the detection of total antibodies (immunoglobulin G [IgG] and IgM) specific for hepatitis E virus (HEV) was developed by utilizing well-characterized recombinant protein ET2.1 and its peroxidase-labeled counterpart. Our study showed that the ELISA detected all the positive patient samples (n = 265) regardless of whether they contained IgM or IgG antibodies, or both, while it maintained an excellent specificity of 98.8% with samples from various patient or healthy control groups (total number of samples, 424). The test had a detection limit for anti-HEV IgG antibodies that was equivalent to 62 mIU/ml of the international reference. Compared with the serological status of the specimens determined on the basis of tests performed at the individual collection sites, the testing outcome generated by the new ELISA had a good agreement of 99.3%, with a kappa value of 0.985. The positive predictive value and the negative predictive value for the new test reached 98.1% and 100%, respectively. This ELISA had a positive delta value of 4.836 and a negative delta value of 3.314 (where delta is a measure of the number of standard deviations by which the cutoff is separated from the mean of the sample groups) (N. Crofts, W. Maskill, and I. D. Gust, J. Virol. Methods 22:51-59, 1988), indicating that it had an excellent ability to differentiate the infected and noninfected cohorts. Furthermore, the new design enables the detection of antibodies not only in human samples but also in pig samples. Our preliminary data showed that the ELISA could detect seroconversion in samples from pigs at as early as 14 days postinoculation. The potential utility of detecting specific antibodies in pigs will be an added advantage for managing the disease, with suggested zoonotic implications.  相似文献   
944.
We examined alteration of regional cerebral blood flow (rCBF) in a case of Alzheimer's disease (AD) patient with musical hallucination. To detect regions related to musical hallucination, single–photon emission computed tomography (SPECT) imaging of the patient and nine sex, age, and cognitive functionmatched AD patients without delusions and hallucinations were compared using statistical parametric mapping 99 (SPM99). In comparison with controls, the patient had increased rCBF in left temporal regions and left angular gyrus. This profile could be relevant to the neuroanatomical basis of musical hallucinations. This work had been carried out at the Higher Brain Function Clinic of the Ehime University Hospital.  相似文献   
945.

Objective

Alphaviruses such as chikungunya virus, Sindbis virus, o'nyong‐nyong virus, Mayaro virus, and Ross River virus (RRV), are commonly associated with arthralgias and overt arthritides worldwide. Understanding the processes by which arthritogenic viruses cause disease is a prerequisite in the quest for better treatments. In this regard, we have recently established that monocyte/macrophages are mediators of alphavirus‐induced arthritis in mice. We hypothesized that chemokines associated with monocyte/macrophage recruitment may play an important role in disease. The aim of the present investigations was to determine whether bindarit, an inhibitor of monocyte chemotactic protein (MCP) synthesis, could ameliorate alphavirus‐induced rheumatic disease in mice.

Methods

Using our recently developed mouse model of RRV‐induced arthritis, which has many characteristics of RRV disease (RRVD) in humans, the effects of bindarit treatment on RRVD in mice were determined via histologic analyses, immunohistochemistry, flow cytometry, real‐time polymerase chain reaction analysis, enzyme‐linked immunosorbent assay, and electrophoretic mobility shift assay.

Results

Bindarit‐treated RRV‐infected mice developed mild disease and had substantially reduced tissue destruction and inflammatory cell recruitment as compared with untreated RRV‐infected mice. The virus load in the tissues was not affected by bindarit treatment. Bindarit exhibited its activity by down‐regulating MCPs, which in turn led to inhibition of cell infiltration and lower production of NF‐κB and tumor necrosis factor α, which are involved in mediating tissue damage.

Conclusion

Our data support the use of inhibitors of MCP production in the treatment of arthritogenic alphavirus syndromes and suggest that bindarit may be useful in treating RRVD and other alphavirus‐induced arthritides in humans.
  相似文献   
946.
OBJECTIVES: Shooting as method of suicide has increased considerably in Austria over recent decades and represented 23.5% of all suicides among men during the period 1990-2000. It is thought that the availability of guns could lead to their use in acts of suicide, and therefore we investigated the numbers of gun licenses (which constitutes ownership of guns and permission to carry a gun) in the nine Austrian counties and their correlation with suicides by shooting and other methods. METHODS: We studied registered suicides, including the method used, between 1990 and 2000 in Austria and the numbers of gun licenses held in the nine counties of Austria in the same period. RESULTS: We found a strong correlation between the average gun license rate for the period 1990-2000 and suicides by shooting (r = 0.967), and only very weak correlation, and for some of the years under investigation a negative correlation, with other methods of committing suicide (r = 0.117) and the suicide rate in general (r = 0.383). CONCLUSIONS: As shooting as a method of suicide has increased in Austria in recent decades, and is a highly lethal method, the finding that the shooting suicide rate is related to the extent of gun ownership deserves attention, especially as there is evidence that restriction of gun ownership is an important factor in suicide prevention.  相似文献   
947.
OBJECTIVES: The first documented conference on suicide among school pupils was held by the Viennese Psychoanalytical Society in 1910, yet since then research on youth suicide in Vienna and Austria has been sparse. We investigated cases of suicide among Viennese minors over a period of 57 years in terms of prevalence, gender differences, suicide methods and monthly distribution. METHODS: We studied registered suicides among Viennese youths aged 19 or younger occurring between 1946 and 2002 (n = 683). RESULTS: The total suicide rate and the rates for male and female suicides among Viennese minors decreased over the period studied. The mean suicide rate was 6.2 per 100,000 (statistics on suicides per 100,000 were available only for the period 1953-2002), with a male-female ratio of 2.1:1. The predominant suicide method was domestic gas until its detoxification in Vienna. From 1976 jumping from a height became the most common suicide method of Viennese minors; it was also the predominant method among females, whereas hanging was the predominant method among males. Since 1996 the percentage of firearm suicides among males has doubled, and jumping suicides among females have tripled. A greater number of suicides among minors took place during the months of January, June, October and December. CONCLUSIONS: Suicide rates of Viennese minors are on the decline, corresponding to a reported decrease in the general suicide rate in Austria. In view of an observed recent increase in firearm suicides among males and jumping suicides among females aged 19 and younger, further monitoring as well as legal and environmental prevention measures are needed.  相似文献   
948.

AIM

To assess the bioavailability and pharmacokinetics of CAT-354, an anti-IL-13 human monoclonal IgG4 antibody, following subcutaneous (s.c.) and intravenous (i.v.) administration.

METHODS

This was a single-dose, randomized, open-label, parallel-group bioavailability study. Healthy male subjects aged 20–54 years were randomly assigned to one of three dose groups (n= 10/group) to receive CAT-354: 150 mg i.v.; 150 mg s.c. or 300 mg s.c. (two 150 mg injections). Serum pharmacokinetics, adverse events (AEs), vital signs, electrocardiograms and laboratory parameters were assessed.

RESULTS

CAT-354 showed bioavailability of 62% and 60% after 150 mg and 300 mg s.c. doses, respectively, and linear pharmacokinetics over the dose range tested. Peak serum concentrations in the s.c. groups occurred after 3–9 (median 5) days, with a mean elimination half-life of 19.2 ± 3.1 days (150 mg) and 19.4 ± 3.59 days (300 mg) after s.c. and 21.4 ± 2.46 days after i.v. administration. Volume of distribution at steady state (Vss) was 4960 ± 1440 ml kg−1 after i.v. (slightly greater than plasma volume). Average apparent clearances (CL/F) were 292 ± 82.3 and 307 ± 109 ml day−1 after 150 and 300 mg s.c., respectively; systemic CL of 188 ± 84.0 ml day−1 after i.v. dosing was consistent with endogenous IgG and reticuloendothelial elimination. No severe or serious AEs occurred. Among 40 reported AEs, 25 were headache, sinus disorders/respiratory symptoms and changes in body temperature perception.

CONCLUSIONS

CAT-354 exhibited bioavailability of approximately 60% when given s.c. to healthy male subjects.  相似文献   
949.
PURPOSE: To retrospectively analyze computed tomographic (CT) findings of chronic idiopathic interstitial pneumonia (IIP) and to determine which findings are most helpful for distinguishing IIP from usual interstitial pneumonia (UIP) with univariate and multivariate analyses. MATERIALS AND METHODS: Institutional review board approval and informed consent were not required for this retrospective review of patient records and images. Two observers working independently and without knowledge of the diagnosis evaluated the extent and distribution of various thin-section CT findings (ground-glass opacity, consolidation, reticulation, and honeycombing) in 92 patients (51 men, 41 women; mean age, 56 years; age range, 29-81 years) with a histologic diagnosis of UIP (n = 20), cellular nonspecific interstitial pneumonia (NSIP) (n = 16), fibrotic NSIP (n = 16), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) (n = 11), desquamative interstitial pneumonia (DIP) (n = 15), or lymphoid interstitial pneumonia (LIP) (n = 14). Observers used univariate and multivariate statistical analyses to compare their findings with the extent and distribution of UIP. RESULTS: Observers made the correct diagnosis in 145 (79%) of 184 readings. Multivariate logistic regression analysis showed that the independent findings that distinguished UIP from cellular NSIP were the extent of honeycombing and the most proximal bronchus with traction bronchiectasis (odds ratio, 5.16 and 0.37, respectively); the finding that distinguished UIP from fibrotic NSIP was the extent of honeycombing (odds ratio, 2.10). CT features that distinguished UIP from RB-ILD and DIP included extent of ground-glass opacity (odds ratio, 0.76), thickening of bronchovascular bundles (odds ratio, 1.58), the most proximal bronchus with traction bronchiectasis (odds ratio, 0.22), and the number of segments with traction bronchiectasis (odds ratio, 3.64). CONCLUSION: UIP has a characteristic appearance that usually facilitates distinction from other types of chronic IIPs at thin-section CT. The most useful finding when differentiating UIP from NSIP was the extent of honeycombing.  相似文献   
950.
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