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31.
32.
Patients with germinal center B cell-like (GCB) and non-GCB diffuse large B cell lymphomas (DLBCL) receiving first line therapy have distinct prognosis. We explored the differences in outcome following salvage autologous hematopoietic stem cell (HSC) transplantation between patients with GCB and non-GCB DLBCL. Forty-four patients with relapsed and 15 patients with primary refractory chemosensitive disease undergoing BEAM (BCNU [carmustine], etoposide, cytarabine, melphalan) conditioning and autologous HSC were included. Immunohistochemical analysis was performed for CD10, BCL-6, MUM1 (allowing classification into GCB and non-GCB-like DLBCL) and BCL-2. Median follow-up of survivors was 25 months; median age at the time of transplantation was 60 years (range 17–77). Thirty-two patients (54%) were classified as having GCB and 27 (46%) as having non-GCB-like DLBCL. Patients with GCB and non-GCB DLBCL did not differ in the risk of progression after HSC transplant ( P  = 0·78) or overall survival ( P  = 0·48). In multivariate analysis, only time to progression after initial treatment impacted overall survival. We conclude that patients with relapsed or primary refractory chemosensitive GCB and non-GCB-like DLBCL derive similar benefit from autologous HSC transplant.  相似文献   
33.
Objectives:  Mantle cell lymphoma (MCL) is an incurable B cell lymphoma, and novel treatment strategies are urgently needed. We evaluated the effects of combined treatment with the proteasome inhibitor bortezomib and the histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA) on MCL. Bortezomib acts by targeting the proteasome, and – among other mechanisms – results in a reduced nuclear factor-kappa B (NF-κB) activity. HDACi promote histone acetylation, and also interfere with NF-κB signaling.
Methods:  Human MCL cell lines (JeKo-1, Granta-519 and Hbl-2) were exposed to bortezomib and/or SAHA. Cell viability and apoptosis were quantified by the MTT and annexin-V assay, respectively. Reactive oxygen species (ROS) were analyzed using the fluorophore H2DCFDA. In addition, activated caspases, proteasome- and NF-κB activity were quantified.
Results:  Combined incubation with bortezomib and SAHA resulted in synergistic cytotoxic effects, as indicated by combination index values <1 using the median effect method of Chou and Talalay. The combination of both inhibitors led to a strong increase in apoptosis as compared to single agents and was accompanied by enhanced ROS generation, while each agent alone only modestly induced ROS. The free radical scavenger N -acetyl- l -cysteine blocked the ROS generation and reduced the apoptosis significantly. In addition, coexposure of bortezomib and SAHA led to increased caspase-3, -8 and -9 activity, marked reduction of proteasome activity and decrease of NF-κB activity.
Conclusions:  This is the first report giving evidence that SAHA and bortezomib synergistically induce apoptosis in MCL cells. These data build the framework for clinical trials using combined proteasome and histone deacetylase inhibition in the treatment of MCL.  相似文献   
34.
OBJECTIVES: The aim of this research was to assess the incidence, clinical predictors, and outcome of contrast-induced nephropathy (CIN) after primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). BACKGROUND: Contrast-induced nephropathy is associated with significant morbidity and mortality after PCI. Patients undergoing primary PCI may be at higher risk of CIN because of hemodynamic instability and unfeasibility of adequate prophylaxis. METHODS: In 208 consecutive AMI patients undergoing primary PCI, we measured serum creatinine concentration (Cr) at baseline and each day for the following three days. Contrast-induced nephropathy was defined as a rise in Cr >0.5 mg/dl. RESULTS: Overall, CIN occurred in 40 (19%) patients. Of the 160 patients with baseline Cr clearance >/=60 ml/min, only 21 (13%) developed CIN, whereas it occurred in 19 (40%) of those with Cr clearance <60 ml/min (p < 0.0001). In multivariate analysis, age >75 years (odds ratio [OR] 5.28, 95% confidence interval [CI] 1.98 to 14.05; p = 0.0009), anterior infarction (OR 2.17, 95% CI 0.88 to 5.34; p = 0.09), time-to-reperfusion >6 h (OR 2.51, 95% CI 1.01 to 6.16; p = 0.04), contrast agent volume >300 ml (OR 2.80, 95% CI 1.17 to 6.68; p = 0.02) and use of intraaortic balloon (OR 15.51, 95% CI 4.65 to 51.64; p < 0.0001) were independent correlates of CIN. Patients developing CIN had longer hospital stay (13 +/- 7 days vs. 8 +/- 3 days; p < 0.001), more complicated clinical course, and significantly higher mortality rate (31% vs. 0.6%; p < 0.001). CONCLUSIONS: Contrast-induced nephropathy frequently complicates primary PCI, even in patients with normal renal function. It is associated with higher in-hospital complication rate and mortality. Thus, preventive strategies are needed, particularly in high-risk patients.  相似文献   
35.
Acute renal failure (ARF) requiring hemodialysis after percutaneous coronary interventions (PCI) is a serious complication with poor prognosis. Hemodialysis-induced hypotension may have deleterious cardiovascular effects, especially in high-risk patients. Ultrafiltrate removal and simultaneous fluid replacement with a solution similar to plasma for high-volume controlled hydration can be obtained with hemodynamic stability by continuous veno-venous hemofiltration (CVVH). We prospectively assessed the safety and effectiveness of percutaneous CVVH (Y-shaped double-lumen catheter, circuit originating from and terminating in the femoral vein) in 33 consecutive patients (23 men and 10 women; mean age, 69 +/- 9 years) who, after PCI, developed oligo-anuric ARF, associated in 20 of them with congestive heart failure. All patients received a concomitant infusion of furosemide (500-1000 mg/day) and dopamine (2 microg/kg/min). During CVVH, the average fluid volume replacement and body fluid net reduction were 1000 +/- 247 and 75 +/- 48 ml/hr, respectively. Treatment with CVVH continued for 4.7 +/- 2.7 days and corrected fluid overload in all cases. No patient experienced systemic hypotension or hypovolemia. Diuresis recovered in 32 (97%) patients, who showed a parallel improvement of renal function parameters. One patient required chronic dialysis. In-hospital and 1-year mortality was 9.1% and 27.3%, respectively. In conclusion, our data indicate that CVVH is a safe and effective therapy of radiocontrast-induced ARF following PCI. It temporarily replaces renal function without deleterious cardiovascular effects, allowing the kidney to recover from the nephrotoxic injury. However, despite promising early results, large randomized trials are required to define the role of CVVH in ARF after PCI.  相似文献   
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It is known that tetanus toxoid (TTd)-hyperimmunization induces increased titer of sera β2-glycoprotein I (β2GPI)-specific antibodies (Abs) in Balb/c mice. The concentrations of such induced anti-β2GPI Abs as well as their pathogenic potential are strongly influenced by the context of TTd application. β2GPI-specific immune response is established as a part of TTd-specific immune response by molecular mimicry mechanism due to structural homology between TTd and β2GPI. This finding is supported by the following facts: (1) cross-reactive Abs that recognize both TTd and β2GPI epitopes are present in Balb/c mice sera; (2) anti-TTd Abs secretion in splenic cultures is induced after β2GPI stimulation and vice versa. However, analyses of (1) IL-10 production following in vitro stimulation of immunized Balb/c mice splenocytes by TTd, β2GPI or glutaraldehyde-treated β2GPI and (2) specific impact of ConA and agonists of TLR2, TLR4, and TLR9 on anti-TTd and autoreactive Abs secretion strongly imply that these two branches of the TTd-induced immune response do not use identical cell populations and are regulated in a different way. Results presented in this paper describe that structural homology between foreign and self-antigens could focus mounted autoreactive immune response toward specific self-structure, but the context of antigen application, including a history of previous immune stimulations and adjuvants applied together with the antigen, are the main factors which determine the outcome of the induced immune response.  相似文献   
38.
39.
Small, non-enveloped RNA viruses belonging to the genera Sapovirus, Kobuvirus, and Mamastrovirus are usually associated with gastroenteritis in humans and animals. These enteric pathogens are considered potential zoonotic agents. In this study, the prevalence and genetic diversity of sapoviruses (SaVs), kobuviruses (KoVs), and astroviruses (AstVs) in asymptomatic pigs were investigated using a PCR approach. KoV was found to be the most prevalent virus (87.3 %), followed by AstV (34.2 %) and SaV (10.2 %). Interestingly, the intra- and inter-cluster distances between porcine SaV capsid sequences revealed one strain (P38/11/CZ) that formed a new genotype within genogroup III of porcine SaVs, and it is tentatively called “P38/11-like” genotype. Moreover, this is the first report of porcine kobuvirus detection on Czech pig farms. The high prevalence rate of gastroenteritis-producing viruses in clinically healthy pigs represents a continuous source of infection of pigs, and possibly to humans.  相似文献   
40.

Aim

To estimate global morbidity from acute bacterial meningitis in children.

Methods

We conducted a systematic review of the PubMed and Scopus databases to identify both community-based and hospital registry-based studies that could be useful in estimation of the global morbidity from bacterial meningitis in children. We were primarily interested in the availability and quality of the information on incidence rates and case-fatality rates. We assessed the impact of the year of study, study design, study setting, the duration of study, and sample size on reported incidence values, and also any association between incidence and case-fatality rate. We also categorized the studies by 6 World Health Organization regions and analyzed the plausibility of estimates derived from the current evidence using median and inter-quartile range of the available reports in each region.

Results

We found 71 studies that met the inclusion criteria. The only two significant associations between the reported incidence and studied covariates were the negative correlation between the incidence and sample size (P < 0.001) and positive correlation between incidence and case-fatality rate (P < 0.001). The median incidence per 100 000 child-years was highest in the African region – 143.6 (interquartile range [IQR] 115.6-174.6), followed by Western Pacific region with 42.9 (12.4-83.4), the Eastern Mediterranean region with 34.3 (9.9-42.0), South East Asia with 26.8 (21.0-60.3), Europe with 20.8 (16.2-29.7), and American region with 16.6 (10.3-33.7). The median case-fatality rate was also highest in the African region (31.3%). Globally, the median incidence for all 71 studies was 34.0 (16.0-88.0) per 100 000 child-years, with a median case-fatality rate of 14.4% (5.3%-26.2%).

Conclusions

Our study showed that there was now sufficient evidence to generate improved and internally consistent estimates of the global burden of acute bacterial meningitis in children. Although some of our region-specific estimates are very uncertain due to scarcity of data from the corresponding regions, the estimates of morbidity and case-fatality from childhood bacterial meningitis derived from this study are consistent with mortality estimates derived from multi-cause mortality studies. Both lines of evidence imply that bacterial meningitis is a cause of 2% of all child deaths.Meningitis is an infectious disease affecting the brain membrane and spinal cord (1). Globally, bacterial meningitis is the most severe type of meningitis, mainly caused by a triad of species Neisseria meningitidis, Streptocccus pneumonia, and Haemophilus influenzae (2). While viral meningitis is usually a self-limiting disease with good prognosis, bacterial meningitis is potentially fatal, requiring urgent medical assistance and management with antibiotics treatment (3). Various estimates of the burden of bacterial meningitis have been proposed to date, but they have mainly focused on mortality (4), long-term sequels (5), or etiology-specific morbidity and mortality (6-8).Interestingly, there have been no comprehensive attempts to estimate the overall global burden of bacterial meningitis in children. This is not surprising, because such attempt would face almost insurmountable methodological challenges. First, there is a problem with case definition of “bacterial meningitis” (9). In low resource settings, where the problem is most common, many children may present with “purulent meningitis,” whose cause is highly likely bacterial, but laboratory capacity may not be sufficient to isolate the causal agent and confirm the diagnosis. This leads to a discrepancy between morbidity burden estimates based on “all purulent meningitis” and “laboratory confirmed meningitis” – the latter always being lower than the former, but to a different extent in different contexts (10). The second large methodological obstacle is the problem of “meningitis belt.” The meningitis belt is the band of countries extending from Senegal to Ethiopia, characterized by semi-arid climate, dry seasons, and dusty winds, with seasonal outbreaks of meningococcal meningitis being recorded since the beginning of the 20th century (11). The problem with these epidemics is that they can last for several years and dramatically change the importance of meningococcus in comparison to the other two bacterial agents (S. pneumoniae and H. influenzae) both regionally and globally (11). This makes it difficult to express the “burden of disease” for any given year, because it will be very different in intra-epidemic and inter-epidemic years. Moreover, the extent of vaccine coverage against N. meningitidis, S. pneumoniae and H. influenzae is changing the burden rapidly and rather dramatically in many places, rendering the scarce evidence from before the period of vaccination rather useless and indicates a need of revision (12). Finally, the emergence of HIV/AIDS pandemic led to a substantial number of infected children, whose resistance to other infections is impaired and they present a specific category of population in which the rates of incidence and case-fatality rates may be very different from those in other children (13).It is apparent that meningitis continues to contribute significantly to global mortality and morbidity, but the impact of the efforts to control it is difficult to estimate given that we do not have comprehensive estimates of global morbidity patterns. Understanding the global morbidity from bacterial meningitis would be useful because it would also help to validate the existing mortality estimates through application of appropriate case-fatality rates. The purpose of the present study is to provide a comprehensive assessment of the evidence that is available for estimating the global morbidity from acute bacterial meningitis in children globally. We will also propose initial, robust estimates of the burden, with suggestions on the possible ways to address the methodological challenges in future studies.  相似文献   
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