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31.
Objectives:The purpose of this study was to design, validate, and optimize internally standardized real-time quantitative RT-PCR assays and to identify and avoid problems with assay reliability and examine the impact of an exogenous internal standard.Design and methods:The model system consisted of internally standardized quantitative real-time RT-PCR assays specific for PSA and hK2 mRNA based on time-resolved fluorometric detection of lanthanide chelates.Results:Reproducibility was best when large copy numbers (> 5000 per milliliter blood) were analyzed. Addition of an exogenous target-mimicking internal standard had no significant effect on the reproducibility of the method, but increased the calculated copy numbers by an average of 2-fold.Conclusions:We developed an internally standardized, specific and reproducible real-time RT-PCR analysis method for PSA and hK2 mRNA in circulating cells in the bloodstream. Both PSA and hK2 assays are sufficiently sensitive to detect two LNCaP cells per milliliter whole blood.  相似文献   
32.

Objective

The long-term morphological changes induced by a single episode of alcoholic pancreatitis are not known. Our aim was to study these morphological changes in secretin-stimulated magnetic resonance cholangiopancreatography (S-MRCP) after the first episode of alcohol-associated acute pancreatitis and to evaluate the risk factors and possible protective factors potentially associated with later chronic findings. We have previously reported 2-year follow-up results in pancreatic morphology. This study extends the follow-up to 9 years.

Patients and Methods

In this prospective follow-up study, S-MRCP imaging was performed for 44 (41 M, 3 F; mean age, 46 (25–68)?years) patients after their first episode of alcohol-associated pancreatitis. Pancreatic morphology was evaluated at 3 months and at 2, 7, and 9 years after hospitalization. Recurrent attacks of pancreatitis were studied and pancreatic function was monitored by laboratory tests. Patients’ alcohol consumption was evaluated with questionnaires, laboratory markers, and self-estimated alcohol consumption via interview. Smoking and body mass index were annually recorded.

Results

At 3 months, 32 % of the patients had normal findings in S-MRCP, 52 % had acute, and 16 % had chronic changes. At 7 years, S-MRCP was performed on 36 patients with normal findings in 53 %, the rest (47 %) having chronic findings. Pancreatic cyst was present in 36 %, parenchymal changes in 28 %, and atrophy in 28 % of the cases. There were no new changes in the pancreas in the attending patients between 7 and 9 years (18 patients). Of the patients with only acute findings at 3 months, 60 % resolved to normal in 7 years, but the rest (40 %) showed chronic changes later on. The initial attack was mild in 65 %, moderate in 25 %, and severe in 10 % of the patients. Patients with mild first attack had fewer chronic changes at 7 years compared to patients with moderate or moderate and severe together (p?=?0.03, p?=?0.01). Of the patients in the seventh year of S-MRCP, 22 % had suffered a recurrent episode of acute pancreatitis (mean, 22 (2–60)?months) and 11 % had a clinical diagnosis of chronic pancreatitis. At 7 years, 88 % of the patients with recurrences had chronic findings in S-MRCP versus 36 % with nonrecurrent pancreatitis (p?=?0.02). Six (17 %) patients abstained from alcohol throughout follow-up (mean, 8.7 (7–9.1)?years), but even one of these developed pancreatic atrophy. Out of the non-abstinent patients who did not suffer recurrences, 4/22 (18 %) had developed new findings during at follow-up S-MRCP (NS). In univariate analysis, heavy smoking showed no correlation with increased chronic changes compared to nonsmoking.

Conclusions

Morphological pancreatic changes increase with recurrent episodes of acute pancreatitis. Patients with mild first attack have fewer chronic changes in the pancreas in the long term. However, even a single episode of acute alcoholic pancreatitis may induce chronic morphological changes in long-term follow-up.  相似文献   
33.
BackgroundPrevious population studies have presented conflicting results regarding the prognostic impact of intraventricular conduction delays (IVCD).MethodsWe studied long‐term prognostic impact and the association with comorbidities of eight IVCDs in a random sample of 6,299 Finnish subjects (2,857 men and 3,442 women, mean age 52.8, SD 14.9 years) aged 30 or over who participated in the health examination including 12‐lead ECG. For left bundle branch block (LBBB) and non‐specific IVCD (NSIVCD), two different definitions were used.ResultsDuring 16.5 years’ follow‐up, 1,309 of the 6,299 subjects (20.8%) died and of these 655 (10.4%) were cardiovascular (CV) deaths. After controlling for known clinical risk factors, the hazard ratio for CV death, compared with individuals without IVCD, was 1.55 for the Minnesota definition of LBBB (95% confidence interval 1.04–2.31, p = .032) and 1.27 (95% confidence interval 0.80–2.02, p = .308) for the Strauss’ definition of LBBB. Subjects with NSIVCD were associated with twofold to threefold increase in CV mortality depending on the definition. While right bundle branch block, left anterior fascicular block and incomplete bundle branch blocks were associated with seemingly higher mortality, this was no longer the case after adjustment for age and sex. The presence of R‐R’ pattern was not associated with any adverse outcome.ConclusionsIn a population study with long‐term follow‐up, NSIVCD and Minnesota definition of LBBB were independently associated with CV mortality. Other IVCDs had no significant impact on prognosis. The prognostic impact of LBBB and NSIVCD was affected by the definition of the conduction disorder.  相似文献   
34.
Three human protoparvoviruses, bufavirus (BuV), tusavirus (TuV) and cutavirus (CuV), have recently been discovered in diarrheal stool. BuV has been associated with diarrhea and CuV with cutaneous T-cell lymphoma, but there are hardly any data for TuV or CuV in stool or respiratory samples. Hence, using qPCR and IgG enzyme immunoassays, we analyzed 1072 stool, 316 respiratory and 445 serum or plasma samples from 1098 patients with and without gastroenteritis (GE) or respiratory-tract infections (RTI) from Finland, Latvia and Malawi. The overall CuV-DNA prevalences in stool samples ranged between 0–6.1% among our six patient cohorts. In Finland, CuV DNA was significantly more prevalent in GE patients above rather than below 60 years of age (5.1% vs 0.2%). CuV DNA was more prevalent in stools among Latvian and Malawian children compared with Finnish children. In 10/11 CuV DNA-positive adults and 4/6 CuV DNA-positive children with GE, no known causal pathogens were detected. Interestingly, for the first time, CuV DNA was observed in two nasopharyngeal aspirates from children with RTI and the rare TuV in diarrheal stools of two adults. Our results provide new insights on the occurrence of human protoparvoviruses in GE and RTI in different countries.  相似文献   
35.
Common chronic infections including those caused by cytomegalovirus (CMV), herpes simplex viruses (HSV), Helicobacter pylori and Chlamydia pneumoniae have previously been related to increased risk of coronary heart disease (CHD). We investigated the association between serology of these chronic infections and coronary bypass graft occlusions in 61 patients. As a result, IgG seropositivity rate against H. pylori was higher among patients without occlusion (82%) than in those with occlusion (45%) or apparently healthy controls (57%) (p = 0.004 and p = 0.008, respectively). In conclusion, H. pylori infection, as judged by IgG seropositivity, is associated with lower occurrence of venous bypass graft occlusion in patients with CHD and may thus be connected with better outcome and prognosis of CHD patients after bypass graft surgery.  相似文献   
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Acute stress can affect cognitive processing and decrease performance in demanding, stressful situations. Here, we recorded the cardiac indices of stress, that is, the heart rate and heart rate variability together with the physical activity of nuclear power plant operators, and examined their association with crew performance, while the operator crews were managing simulated incident and accident situations. Crew performance was evaluated both by the operator instructor and as the time taken to resolve the situation. In total, 64% of the variance in the information-seeking performance (adj-R2 = .64, p < .01), and 41% of variation in the performance time (adj-R2 = .41, p < .01) were explained by the psychophysiology. The cardiac measures indicated that increased stress was associated with poorer information-seeking performance and longer performance time. Increased physical activity was associated with poorer information seeking only. Otherwise, crew performance was robust, as the diagnosis and corrective actions, use of emergency operations procedures, and collaboration, were only weakly associated with the stress physiology. The association between information-seeking performance and stress might be explained by the larger requirement for cognitive processing at the information-gathering phase of the task. The results of the study show that psychophysiological measurements of stress and activity can provide valuable information on stress and its association with cognitive performance at work.  相似文献   
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Human hepatitis D virus (HDV) depends on hepatitis B virus co-infection and its glycoproteins for infectious particle formation. HDV was the sole known deltavirus for decades and believed to be a human-only pathogen. However, since 2018, several groups reported finding HDV-like agents from various hosts but without co-infecting hepadnaviruses. In vitro systems enabling helper virus-independent replication are key for studying the newly discovered deltaviruses. Others and we have successfully used constructs containing multimers of the deltavirus genome for the replication of various deltaviruses via transfection in cell culture. Here, we report the establishment of deltavirus infectious clones with 1.2× genome inserts bearing two copies of the genomic and antigenomic ribozymes. We used Swiss snake colony virus 1 as the model to compare the ability of the previously reported “2× genome” and the “1.2× genome” infectious clones to initiate replication in cell culture. Using immunofluorescence, qRT-PCR, immuno- and northern blotting, we found the 2× and 1.2× genome clones to similarly initiate deltavirus replication in vitro and both induced a persistent infection of snake cells. The 1.2× genome constructs enable easier introduction of modifications required for studying deltavirus replication and cellular interactions.  相似文献   
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