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1.
Concrete plants accumulate large amounts of concrete wash water. This water, which pH is highly alkaline, has a negative impact on the environment. Its reuse in fresh concrete slightly reduces its mechanical properties. The combination of concrete wash water and zeolitic by-product led to an increase of 4.6% in the compressive strength at 7 days hydration and up to 30% at 28 days hydration. The same combination led to the denser microstructure compared to the samples made with concrete wash water. This could be explained by the pozzolanic reaction of the zeolitic by-product. The complex chemical reactions of cement, zeolitic by-product, and fines presented in the concrete wash water occurred. Therefore, it was suggested the reusing method of concrete wash water together with zeolitic by-product in the fresh concrete mixtures by substituting some amount of tap water with concrete wash water. In this way, the consumption of tap water is possible to reduce in cement systems.  相似文献   
2.
The objective of the study was to assess and perceive the vocal and pharyngeal symptoms and acoustic changes of voice after short-term endotracheal intubation and to evaluate the relation between these changes and the endotracheal tube parameters, number of intubation attempts, duration of anaesthesia, experience of anaesthesiologist. A total of 108 patients were evaluated preoperatively, 1–2 and 24 h after extubation. The vocal and pharyngeal symptoms, voice acoustic characteristics and maximum phonation time (MPT) were evaluated to find the relationship with endotracheal tube parameters, number of intubation attempts, duration of anaesthesia, experience of anaesthesiologist. All vocal and pharyngeal symptoms increased significantly at 24 h and remained significantly increased at 24 h after general anaesthesia. The vocal acoustic parameters changed significantly at 1–2 h: decrease of MPT and increase relative average perturbation were recorded. The day after the short-term intubation: only noise to harmony ratio and habitual pitch remains significantly changed. The most important endotracheal tube parameters that affect significantly (P value <0.05) the vocal function were the size of tube, cuff volume and number of intubation attempts. In relation to the anaesthesia, the changes of the acoustic parameters did not associate significantly with the anaesthesia-related parameters. No statistically significant relationship between experience of an anaesthesiologist and changes of the voice after anaesthesia was detected. Though being short-term, endotracheal anaesthesia is an invasive procedure, and its temporary influence on vocal function is important.  相似文献   
3.
We present a 67-year-old right-handed male with a brachium pontis arteriovenous malformation on continuous anti-emetic therapy who demonstrated acute withdrawal symptoms after the abrupt discontinuation of ondansetron, a 5-HT(3) receptor antagonist. Removal of anti-emetic therapy led to the development of extreme flushing and tremor, but subsequent return of ondansetron resulted in the resolution of these symptoms. This is the first clinical report demonstrating acute withdrawal from an anti-emetic agent and we further highlight the need for future studies evaluating not only arterial supply with pressure gradients and anatomical location, but also the association with periventricular venous drainage, venous drainage stenosis, and mass effect from venous stasis as this may contribute partly to the sensitivity of the serotonergic receptors seen here.  相似文献   
4.
Micronuclei (MN) were analyzed in erythrocytes of flounder (Platichthys flesus) and wrasse (Symphodus melops) and in gill cells of blue mussels (Mytilus edulis). The organisms were collected from three study stations in the Baltic Sea and from seven stations in the North Sea (Karmsund area, Norway) 4 times. The statistically significant differences obtained were related to the season, sex of the fish, and sampling locality. Higher MN frequencies were found in fish and mussels collected from the most polluted study stations in the North Sea. The same tendency could be described in the Baltic Sea; however, it was masked by the recent oil spill from the Butinge oil terminal. Our results showing higher MN frequencies in presumably what were the most polluted study locations suggest that MN tests in fish and mussels may be used for the detection of genotoxic effects in a marine environment. The endpoint is well characterized and can be easily recognized, and the technique is convenient to use in field samplings following standard procedures and protocols.  相似文献   
5.
In this article, the question is discussed if and how Healthcare Ethics Committees (HECs) should be regulated. The paper consists of two parts. First, authors from eight EC member countries describe the status quo in their respective countries, and give reasons as to the form of regulation they consider most adequate. In the second part, the country reports are analysed. It is suggested that regulation of HECs should be central and weak. Central regulation is argued to be apt to improve HECs’ accountability, relevance and comparability. To facilitate biomedical citizenship and ethical reflection, regulation should at the same time be weak rather than strict. Independence of HECs to deliberate about ethical questions, and to give solicited and unsolicited advice, should be supported and only interfered with by way of exception. One exception is when circumstances become temporary adversarial to ethical deliberation in healthcare institutions. In view of European unification, steps should be taken to develop consistent policies for both Eastern and Western European countries.  相似文献   
6.
AIM: To compare efficacy of use of the blocker of aldosteron receptors spironolactone and diuretic indapamide in low-renin arterial hypertension (AH), their action on blood pressure, serum concentrations of sodium, potassium, creatinine, plasmic renin activity (PRA), plasmic aldosteron concentration (PAC). MATERIAL AND METHODS: The study included 31 females aged 40-60 years with hardly correctable AH and high PAC to (PRA) ratio. Biochemical parameters were measured before 2-week treatment with indapamide (1.5 mg/day) and spironolactone (25 mg/day) and after the treatment. Between the courses there was a 2-week interval. RESULTS: In AH patients with high PAC/PRA spironolacton reduced AP more significantly (-15.5 / -8.2 mmHg) than indapamide (-10.9 / -5.9 mmHg). Indapamide lowered potassium serum levels by 0.28 mmol/l (p < 0.05), spironolacton raised it by 0.26 mmol/l (p = 0.05). Sodium concentration in the serum reduced only after treatment with spironolactone. Both drugs increased blood concentrations of creatinine, aldosteron, PRA, but spironolactone was more active. CONCLUSION: In treatment-resistant AH it is necessary to perform screening for detection of patients with low-renin hypertension. Such patients are effectively treated with spironolacton in low doses.  相似文献   
7.
Amplitude ratios of two adjacent mixed blood oxygen saturation curve peaks in randomly selected strips of ECG were analysed in 32 patients with regular wide-QRS complex tachycardias and 60 control subjects where pacing was performed before ablation of narrow-QRS complex tachycardias. Patients with VT showed different patterns of A-to-V relationships, leading to varying ratios of SpO2 adjacent peak amplitudes, in contrast to patients with aberrant SVTs and 1:1 AV association. Application of a criterion of adjacent SpO2 peaks differing by twofold or more had a sensitivity of 90.0% and specificity of 83.3% to detect AV dissociation during VT. Fluctuations on the mixed oxygen saturation curve may be a useful non-invasive clinical parameter to detect different ventricular filling caused by atrio-ventricular dissociation during VT.  相似文献   
8.
Protoporphyrin IX (Pp IX) is the main photosensitizer in photochemotherapy with 5-aminolevulinic acid (ALA). Pp IX is photolabile and the present work shows that 70–95% of Pp IX in cells is degraded by clinically relevant light exposures (40–200 J cm−2 at 630 nm). During light exposure a small yield of photoprotoporphyrin, which is also photolabile, is formed. A substantial fraction of Pp IX in cells incubated with ALA is bound to proteins. During light exposure these binding sites are destroyed, those close to tryptophan residues being the most sensitive. The rate of photodegradation of Pp IX in the cells is dependent on the initial concentration of Pp IX. The degradation mechanisms are therefore not only first order processes. Different degradation rates appear to be related to different types of binding sites. During light exposure, Pp IX molecules appear to move to different binding sites, evidently sites that are more vital for cell survival. Thus, the yield of photoinactivation of the cells, as measured per emitted photon of Pp IX fluorescence, increased during light exposure. © 1997 Wiley-Liss, Inc.  相似文献   
9.
10.
High-sensitivity troponin assay brought new challenges as we detect elevated concentration in many other diseases, and it became difficult to distinguish the real cause of this elevation. In this notion, diagnosis of acute coronary syndrome (ACS) remains a challenge in emergency department (ED).We aim to examine different approaches for rule-in and rule-out of ACS using risk scores, copeptin, and coronary computed tomography angiography (CCTA).A prospective observational study was designed to evaluate chest pain patients. Consecutive adult patients admitted to the ED with a chief complaint of chest pain due to any cause were included.All patients were followed-up for 6 months after discharge for major adverse cardiovascular events and readmissions. Admission data, ED processes, and diagnoses were analyzed.One hundred forty-six patients were included, average age was 63 ± 13.4 years, and 95 (65.1%) were male. Global Registry of Acute Coronary Events (GRACE) and History, ECG, Age, Risk factors, Troponin (HEART) scores showed good prognostic abilities, but HEART combination with copeptin improves diagnoses of myocardial infarction (area under the curve [AUC] 0.764 vs AUC 0.864 P = .0008). Patients with elevated copeptin were older, had higher risk scores, and were more likely to be admitted to hospital and diagnosed with ACS in ED. For copeptin, AUC was 0.715 (95% confidence interval 0.629–0.803), and for combination with troponin, AUC of 0.770 (0.703–0.855) did not improve rule-in of myocardial infarction. High-sensitivity troponin I assay alongside prior stroke, history of carotid stenosis, dyslipidemia, use of diuretics, and electrocardiogram changes (left bundle branch block or ST depression) are good predictors of myocardial infarction (χ² = 52.29, AUC = 0.875 [0.813–0.937], P < .001). The regression analysis showed that combination of copeptin and CCTA without significant stenosis can be used for ACS rule-out (χ² = 26.36, P < .001, AUC = 0.772 [0.681–0.863], negative predictive value of 96.25%).For rule-in of ACS, practitioner should consider not only scores for risk stratification but carefully analyze medical history and nonspecific electrocardiogram changes and even with normal troponin results, we strongly suggest thorough evaluation in chest pain unit. For rule-out of ACS combination of copeptin and CCTA holds great potential.  相似文献   
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