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1.
Reducing medical errors has become an international concern. Population-based studies from a number of nations around the world have consistently demonstrated unacceptably high rates of medical injury and preventable deaths. The introduction of effective reporting systems is a cornerstone of safe practice within hospitals and other healthcare organisations. Reporting can help to identify hazards and risks. However, reporting in itself does not improve safety. It is the response to reports that leads to change. Clinical teams must feel empowered to change the way in which they deliver their services, promoting effective clinical risk management. Process analysis, implementation of evidence-based practices, and a clear accountability system are effective tools not only for decreasing error rates, but also for improving effectiveness. Clinical Governance represents the context in which effective clinical risk management should be promoted and continuously improved. It should not be regarded as a separate activity, but should form part of the everyday practice of all healthcare professionals. It requires good multidisciplinary working and a willingness to reflect on and learn from errors to achieve a patient-centred and safer system.  相似文献   
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1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage.  相似文献   
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Patients with agammaglobulinemia may excrete enteroviruses, including vaccine-derived poliovirus, for prolonged periods of time. This poses a risk to the patients but it also may pose a risk to the population after eradication of poliovirus and the cessation of routine vaccination. To assess this risk, a pilot study was performed to identify potential poliovirus long-term excretors in a cohort of 38 patients with a definite/presumptive diagnosis of X-linked agammaglobulinemia (XLA). Stool samples were analyzed to detect any polio or other enteroviruses replicating in the gut and neutralizing antibodies against polioviruses were measured in the sera. No viruses were isolated from the stool samples and most sera had neutralizing antibody levels against all three poliovirus serotypes considered by the WHO to be protective in immunocompetent individuals. This suggests that long-term excretion of enteroviruses in patients with agammaglobulinemia is relatively uncommon.  相似文献   
5.
The objectives of this study were to determine: 1) levels of tear eosinophil cationic protein (ECP) in patients with vernal keratoconjunctivitis (VKC); 2) the effect of pharmacologic therapy on ECP release; and 3) the correlation of this mediator with the severity of the disease. Tears were collected from 10 controls and 20 VKC patients before and after therapy for cytologic analysis and ECP measurement by radioimmunoassay. Ocular signs and symptoms were evaluated before tear collection. Mean ECP levels in controls were 7.5 ± 0.4 μg/l, and in VKC patients, 988.3 ± 128 μg/l before therapy ( P <0.001) and 566.3 ± 121 μg/l after therapy ( P <0.005). In dexamethasone (Dex) 0.1%, or cyclosporin A (CsA) 2%, patients (five per group), tear ECP decreased significantly after 7–14 days of treatment. Disodium cromoglycate (DSCG) 4% (five patients) for 14 days did not significantly affect ECP levels. ECP levels were significantly correlated with allergic signs ( P <0.001), symptoms ( P <0.001), and the number of eosinophils in tears (P<0.005). The results of this study suggest that tear ECP levels accurately reflect the clinical status of VKC patients. The measurement of ECP may prove useful not only in the diagnosis and monitoring of allergic disease, but also as an objective parameter for the evaluation of new antiallergic therapies.  相似文献   
6.
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG.  相似文献   
7.
Summary: CD40 is a member of the tumor necrosis factor receptor family, which is expressed by a variety of cells including B cells, macrophages, dendritic cells, and other nonimmune cell types. CD40 activation is critical for B‐cell proliferation, immunoglobulin (Ig)‐isotype switching, and germinal center formation. In physiological conditions, the activation of CD40 occurs by binding to its natural ligand, CD154, which is expressed on activated T cells. The in vivo critical role of CD40–CD154 interaction on B‐cell differentiation and isotype switching is provided by the discovery that mutations in either CD40 or CD154 gene cause the hyper IgM syndrome, termed HIGM3 or HIGM1, respectively, characterized by very low levels of serum IgG, IgA, and IgE, with normal or elevated IgM, associated with a defective germinal center formation. Originally considered humoral primary immunodeficiencies, the clinical features and the defect of T‐cell priming, resulting from a defective T–B cell or dendritic cell interaction, is now considered as combined immunodeficiencies. In this article, we present a comprehensive overview of the clinical, genetic, and immunological features of patients with hyper IgM syndrome due to CD40 mutations.  相似文献   
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We analysed HIV-specific immunoglobulin G (IgG) responses to gag and env peptides in infants born to HIV-positive mothers. Questions of interest were whether there are early specific markers for prognosis, and whether any specific IgG is related to the prevention of vertical transmission of infection. Fifty-three children, 0-24 months old and born to HIV-1-infected mothers, were retrospectively divided into two groups based on HIV seroreactivity or non-reactivity at 15 months of age. Their sera were used to find reactivities important in diagnosis and/or prediction of the putative HIV disease. Three important findings emerged. First, a low IgG titer against the very immunodominant penv9 in newborns was found to be associated with rapid progression to AIDS. This difference was clearly reflected in the reactivity to a small peptide representing amino acid (aa) 598-606. The second interesting finding was the putative hypervariable loop on gp120 (especially aa 324-338), reactivity to which was found only in the uninfected group, and was seen in six out of 19 uninfected children under 6 months of age. This specific response was not caused by a generally high total anti-HIV reactivity, and may indicate a role of protective antibodies against vertical transmission. The response to this region in the infected group, on the other hand, was directed to the amino terminal half of the putative loop, in particular peptide 53, aa 304-318. Finally, response to a part of the amino terminal end of P17 was seen in seven out of eight infected children over 6 months of age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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