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Elevated body temperature (Tcore) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (Tbrain) is usually higher than Tcore. However, the implication of this difference (Tdelta) remains unclear. We aimed to study factors associated with higher Tdelta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of Tcore, Tbrain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. Tbrain was tightly correlated with Tcore (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (Tdelta +0.18°C, IQR −0.01 – 0.37°C). A higher Tdelta was associated with better metabolic state, indicated by lower CMD-glutamate (p = 0.003) and CMD-lactate (p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, Tdelta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher Tdelta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that Tbrain is associated with brain metabolic activity and exceeds Tcore when mitochondrial function is preserved. Further studies are needed to understand how Tdelta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH.  相似文献   
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BACKGROUND: The high rate of local recurrence after radical resection of pancreatic adenocarcinoma fosters intensive efforts to develop new approaches for adjuvant treatment. The established animal models show significant limitations in simulating an adjuvant therapeutic setting. For optimal approximation to the clinical situation we therefore improved a murine orthotopic human xenotransplantation model. METHODS: Subtotal pancreatectomy in mice was performed after orthotopic inoculation of human pancreatic cancer cells and manifestation of solid tumours. The natural course of disease, tumour growth and metastases were analysed. Gemcitabine as a cytotoxic drug was tested in vitro on the cell line used in this model and the effect of adjuvant treatment with gemcitabine in vivo was investigated. RESULTS: All tumour-resected animals showed local recurrence. Organ metastases occurred in 67% in resected compared to 25% of non-resected animals. Gemcitabine in vitro was ineffective, but as adjuvant monotherapy resulted in a highly significant reduction of tumour weight and metastatic events. CONCLUSION: Subtotal pancreatectomy for xenotransplanted pancreatic cancer in SCID beige mice is feasible. Due to high rates of local recurrence and increased organ metastases, this model offers a relevant option for preclinical adjuvant testing, especially as in vitro and in vivo effects of cytotoxic drugs differ enormously.  相似文献   
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BackgroundProprioception has been defined as the capacity to feel the position of a joint in space as sensed by the central nervous system. Prophylactic knee braces are supposed to help in knee injury prevention not just with a mechanical support of the joint but also improving proprioception. The main aim of this study was to determine the effects of a knee brace and a knee sleeve on knee proprioception. The secondary aim was to determine if different starting angles of the knee and different movement directions influence knee proprioception.MethodsWe tested a group of twenty healthy male sport students without knee injuries. They were tested with the brace, with the sleeve and without support. The threshold of detection of passive knee movement with a starting knee angle of 30° and 60°, both in flexion and extension was determined.ResultsWe did not find any statistically significant change in the threshold of detection of passive knee movement wearing the brace or the sleeve compared to the unsupported condition (p = 0.462, α = 0.05). We found a significantly lower proprioceptive sensitivity starting at the more flexed knee angle (p = 0.005, α = 0.05) and moving in extension than in the other test situations (p = 0.001, α = 0.05).ConclusionMovement direction and starting position appear to influence the threshold of detection of passive knee movement. The results of this study also suggest that knee supports do not influence either positively or negatively knee proprioception of uninjured active subjects.  相似文献   
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Evaluation of tube position is important after in-hospital and prehospital emergency intubation. Colorimetric breath indicators are devices for immediate control of tube positioning by showing a color change according to end-tidal CO2 (ETCO2) concentrations. We hypothesized that colorimetric breath indicators can yield reliable results for confirmation of tube position. The aim of this study was to evaluate the effectiveness and safety of a new colorimetric breath indicator (Colibri, ICOR AB, Bromma, Sweden) in 147 patients during general anesthesia, in critically ill patients, during transport to in-hospital interventions, and in a study design after insertion of a second tube into the esophagus in long-term ventilated patients. The Colibri was attached between the respective airway and ventilatory tubing. Seventy-three patients were investigated during general anesthesia, 39 patients were observed during long-term ventilation with an average duration of 33 hours, in 15 patients during transport to an intervention for up to 4 hours, and in 20 long-term ventilated patients at the medical intensive-care unit after insertion of a second tube intentionally into the esophagus with the help of a laryngoscope. The Colibri worked well in all groups investigated and showed no false results in the group with tubes inserted into the trachea and esophagus. Data suggest that the Colibri might serve as a valuable tool for evaluating and controlling tube position. This device is independent of power supply or electronic equipment, portable, small, and immediately ready for use.  相似文献   
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Objective To assess in patients with multiple trauma the relevance of the following as predictive markers for infections: the inflammation parameters white blood count, body temperature, blood polymorphonuclear leukocyte (PMN) migration; blood levels of C-reactive protein, PMN elastase, procalcitonin, neopterin, interleukin 6, interleukin 8, malondialdehyde, total antioxidative status; the stress parameters cortisol and lactate.Design Prospective observational cohort study.Setting Intensive Care Unit of a university surgical department.Patients Twenty-six patients with multiple trauma of differing severity.Measurements and results Trauma severity was estimated by the ISS. PMN migration upon F-Met-Leu-Phe stimulation was determined in fresh whole blood in a ready-for-use, one-way membrane filter assay and evaluated by automated image analysis. The other parameters were measured with commercially available tests. During hospitalization, nine patients developed infections, and 17 patients were free of infection. PMN migration below a critical minimum preceded infections in eight of the infected, but occurred in only three of the non-infected patients (positive/negative predictive values 0.72/0.93; sensitivity/specificity 0.88/0.82; likelihood ratio 5.0). Fever (38.0 °C) had predictive values of 0.83/0.80 and a high likelihood ratio of 9.4, but a low sensitivity/specificity of 0.55/0.94. The other parameters were without significance. Procalcitonin, elastase, C-reactive protein, neopterin and lactate correlated positively with the injury severity score.Conclusion PMN migration proved to be a highly sensitive predictive marker for infections. The whole-blood PMN migration test may facilitate early aggressive antimicrobial therapy.Coauthors are listed in alphabetical order  相似文献   
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The structure and organization of the human vitamin-D-binding protein gene (DBP, group-specific component, GC) have recently been determined. Each ex-on may now be amplified by the PCR method using oligonucleotide primers deduced from the intron sequences near their 5' ends and 3' ends. In this study we examined the anodal GC variants 1A1 and 2A9. Genomic DNA of the variant 1A1 was obtained from Australian Aborigines and from South African Bantu-speaking Blacks. Amplification and sequencing of exon 11 of 1A1 revealed a point mutation in codon 429 at the second position. It is remarkable that this mutation was found in the Australian 1A1 variant and in the African 1A1 variant, and raises the question whether the mutation in these two ethnic groups has a common origin. Genomic DNA of the 2A variant called 2A9 was obtained from South Germany and a point mutation also concerning position 429 in exon 11 was found. The nucleotide exchange in this case, however, was at the first position of the codon. The widely distributed genetic polymorphism of DBP/GC is located in exon 11 and is characterized by substitution at amino acid positions 416 and 420. Variant 1A1 is due to a second site mutation of the allele GC*1F; variant 2A9 is due to a mutation in the GC*2 allele.  相似文献   
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