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141.
The negative influence of hypercholesterolemia on the blood vessels condition and following degeneration lesions of the organs is well known. The aim of our study was to estimate the lipid balance disorders influence on the small blood vessels of the brain and inner ear in the patients with hypercholesterolemia and hypertriglyceridemia on the base of the audiometric, ABR and TEOAE evaluations. In our study we observed no statistical significant differences between the mean auditory thresholds in the study and control groups as well as statistical negative correlation between cholesterol serum level and amplitudes of TEOAE. In the ABR evaluation we stated the prolonged latency of the wave III and V as well as I-III and III-V interpeaklatencies in the patients with hyperlipidemia in comparison with the control group.  相似文献   
142.
143.
The main purpose of our study was to assess the effects of prenatal tobacco smoke on respiratory symptoms and on doctor consultations in a birth cohort of 445 infants who had no smoking mothers and who had no postnatal exposure to environmental tobacco smoke (ETS). Before and after delivery, questionnaires and interviews with mothers were administered to solicit information on prenatal and postnatal ETS exposure. Newborns were followed-up over six months of life, and respiratory outcomes such as runny or stuffed nose, cough with or without cold, difficult (puffed) breathing, wheezing or whistling in the chest irrespective of respiratory infection were considered. In addition, medical visits related to the occurrence of respiratory symptoms were recorded for each child over a six-month study period. In the multivariate Poisson regression analysis, a set of potential confounders has been taken into account such as gender of child, season of birth, gestational age, maternal education, maternal atopy, presence of moulds in households and prenatal level of personal exposure to fine particles. The adjusted rate ratio (RR) estimated for the occurrence of episodes of running nose was significantly higher in infants exposed to prenatal ETS (1.40; 95% confidence interval [CI]: 1.11-1.68) and the corresponding RR estimates for cough, difficult breathing and wheezing were 1.49 (95% CI: 1.15-1.93), 1.96 (95% CI: 1.22-3.16) and 5.12 (95% CI: 2.86-9.16). The rate ratios of doctor consultations attributable to prenatal ETS because of cough was 1.94 (95% CI: 1.49-2.54). The risk estimate for consultations due to difficult breathing was 2.77 (95% CI: 1.76-4.36), and that for wheezing was 5.86 (95% CI: 3.56-9.64). The data strongly support the view about the impact of the in-utero effect of passive smoking on children's respiratory health. Higher utilization rates of doctor consultations in infants attributable to prenatal ETS exposure demand the revision of public health policy, which should be focused also on cessation of smoking practices by all household members during and after the pregnancy period.  相似文献   
144.
The interaction of mianserin with ethanol in central nervous system (CNS) was investigated. Mianserin was administered at a single dose of 5 or 20 mgkg(-1) i.p. or as daily injections in a dose of 2.5 mgkg(-1) given for 14 days. The influence of mianserin on acute ethanol toxicity (LD(50)), on ED(50) of ethanol in rota-rod test, on the duration of ethanol sleeping time as well as on spontaneous locomotor activity and ethanol-induced hypothermia was investigated. Moreover, the influence of mianserin administered in a dose of 10 mgkg(-1) i.p. on post-ethanol changes in the bioelectric brain activity (EEG) recordings in rabbits was also investigated. The electrodes were implanted into midbrain reticular formation (MRF), dorsal hippocampus (Hp) and frontal cortex (C).Mianserin administered as a single dose of 5 mgkg(-1) was found to decrease LD(50) of ethanol and its ED(50) in rota-rod test. Mianserin administered as a single dose of 5 or 20 mgkg(-1) prolongs ethanol sleeping time in mice but given daily for 14 days has no influence on this time. Mianserin-induced hypothermia was observed after administration of single dose as well as increase of ethanol-induced hypothermia after administration of higher dose (20 mgkg(-1)). Mianserin administered daily for 14 days had no influence on post-ethanol changes in body temperature. Single dose of mianserin 20 mgkg(-1) decreases locomotor activity in mice while repeated administration has no influence on locomotor activity. In contrast, both single dose and repeated administration of mianserin prevents increased locomotor activity of animals observed after ethanol (2.5 mgkg(-1)).Mianserin administered to rabbits (10 mgkg(-1)) induces increase of share of low frequency 0.5-4 cps and decrease of share of frequencies 4-7 and 7-10 cps in EEG recordings from MRF and Hp. The recordings from frontal cortex show increase of share of frequencies 10-13 cps. Ethanol increases the share of low frequencies in EEG recordings and decreases the share of fast frequencies. Mianserin increases its influence on fast frequencies.  相似文献   
145.
The perioperative course of 41 patients undergoing 85 endoscopic laser resections of central airway lesions under general anaesthesia was reviewed. The CO2 laser was used in 60 procedures and the Nd:YAG in 25. Intravenous anaesthesia and Venturi ventilation were utilized for 65 resections; 20 procedures involved predominantly inhalation anaesthesia via the ventilating bronchoscope. Significant intraoperative complications included arterial desaturation (SaO2 less than 90 per cent) in 26 per cent of procedures, and refractory hypertension requiring vasodilator therapy in 19 per cent. Intravenous anaesthesia was associated with a longer duration of recovery room care and a higher incidence of postoperative respiratory complications (delayed extubation, recovery room re-intubation and ventilation, and post-extubation stridor). Inhalation anaesthesia appeared to simplify the intraoperative management and decrease the incidence, duration and severity of immediate postoperative respiratory complications.  相似文献   
146.
Studies were carried out in 183 non-dialyzed, 123 hemodialysis, 81 continuous ambulatory peritoneal dialysis and 35 post-transplant patients and in 103 healthy subjects as a reference group. Lipids and apolipoprotein (apo)AI and apoB were determined using Roche kits. An anti-apoB antibody was used to separate apoB-containing apoCIII and apoE-triglyceride-rich lipoprotein (TRL) in the non-high-density lipoprotein (non-HDL) fraction from apoCIIInonB and apoEnonB in the HDL fraction in four groups of patients with chronic renal failure (CRF) and healthy subjects. Multivariate linear regression analysis was used to investigate the relationship between triglyceride (TG) or HDL-cholesterol (HDL-C) concentrations and lipoproteins. Dyslipidemia varied according to the degree of renal insufficiency, the type of dialysis and therapy regime in CRF patients. Lipoprotein disturbances were manifested by increased TG, non-HDL-C and TRL concentrations, and decreased HDL-C and apoAI concentrations, whereas post-renal transplant patients showed normalization of lipid and lipoprotein profiles, except for TG levels and total apoCIII and apoCIIInonB. The present study indicates that CRF patients have disturbed lipoprotein composition, and that hypertriglyceridemia and low HDL-C concentrations in these patients are multifactorial, being secondary to disturbed lipoproteins. The method using anti-apoB antibodies to separate apoB-containing lipoproteins in the non-HDL fraction from non-apoB-containing lipoproteins in HDL can be used in the diagnosis and treatment of patients with progression of renal failure or atherosclerosis. The variability of TG and HDL-C concentrations depends on the variability of TRL and cholesterol-rich lipoprotein concentrations, but the decreases in TG and increases in HDL-C concentrations are caused by apoAI concentration variability. These relationships, however, need to be confirmed in further studies.  相似文献   
147.
Atrial fibrillation (AF) occurs approximately in 3% of general population, with greater prevalence in elderly. Non-vitamin K-dependent oral anticoagulant agents (NOACs) according to the current European guidelines are recommended for patients with AF at high risk for stroke as a first-choice treatment. NOACs are not inferior to warfarin or some of them are better than warfarin in reducing the rate of ischemic stroke. Moreover, they significantly reduce the rate of intracranial hemorrhages, major bleedings, and mortality compared with warfarin. Nevertheless according to ESC guidelines, NOACs are not recommended in patients with creatinine clearance?<?30 mL/min. Observational studies provide contradictive data. Only few new trials are ongoing. Therefore, it is not clear if NOACs should be in the future prescribed to patients with advanced CKD and those on dialysis. Moreover, the risk of stroke and bleeding is much higher in such population than in patients without end-stage renal disease (ESRD). The authors provide data on pros and cons of use of NOACs in ESRD patients with AF.  相似文献   
148.
Loss of ATP Diphosphohydrolase Activity with Endothelial Cell Activation   总被引:18,自引:0,他引:18  
Quiescent endothelial cells (EC) regulate blood flow and prevent intravascular thrombosis. This latter effect is mediated in a number of ways, including expression by EC of thrombomodulin and heparan sulfate, both of which are lost from the EC surface as part of the activation response to proinflammatory cytokines. Loss of these anticoagulant molecules potentiates the procoagulant properties of the injured vasculature. An additional thromboregulatory factor, ATP diphosphohydrolase (ATPDase; designated as EC 3.6.1.5) is also expressed by quiescent EC, and has the capacity to degrade the extracellular inflammatory mediators ATP and ADP to AMP, thereby inhibiting platelet activation and modulating vascular thrombosis. We describe here that the antithrombotic effects of the ATPDase, like heparan sulfate and thrombomodulin, are lost after EC activation, both in vitro and in vivo. Because platelet activation and aggregation are important components of the hemostatic changes that accompany inflammatory diseases, we suggest that the loss of vascular ATPDase may be crucial for the progression of vascular injury.  相似文献   
149.
Twenty-nine Proteus mirabilis isolates from 17 Polish hospitals were analyzed. The isolates were resistant to a variety of antimicrobials, and their patterns of resistance to beta-lactams resembled those of the constitutive class C cephalosporinase (AmpC) producers. Indeed, beta-lactamases with a pI of approximately 9.0 were found in all of the isolates, and they were subsequently identified as four AmpC-type cephalosporinases, CMY-4, -12, -14, and -15, of which the two last ones were novel enzyme variants. The enzymes were of Citrobacter freundii origin and were closely related to each other, with CMY-4 likely being the evolutionary precursor of the remaining ones. The bla(CMY) genes were located exclusively in chromosomal DNA, within EcoRI restriction fragments of the same size of approximately 10 kb. In the CMY-12- and -15-producing isolates, an additional fragment of approximately 4.5 kb hybridized with the bla(CMY) probe as well, which could have arisen from a duplication event during the evolution of the genes. In all of the isolates, the ISEcp1 mobile element, which most probably is involved in mobilization of the C. freundii ampC gene, was placed at the same distance from the 5' ends of the bla(CMY) genes, and sequences located between them were identical in isolates carrying each of the four genes. These data suggested that a single chromosome-to-chromosome transfer of the ampC gene from C. freundii to P. mirabilis could have initiated the spread and evolution of the AmpC-producing P. mirabilis in Poland. The hypothesis seems to be confirmed by pulsed-field gel electrophoresis typing, which revealed several cases of close relatedness between the P. mirabilis isolates from distant centers and showed an overall similarity between the majority of the multiresistant isolates.  相似文献   
150.

Purpose

Activation of hepatic stellate cells (HSCs), mainly responsible for extracellular matrix synthesis, is assumed to be central event in the process of liver fibrogenesis. The major objective of the research was to analyze the ultrastructural profile of activated HSCs in children with chronic hepatitis B (chB), with respect to fibrosis intensity.

Materials/methods

Ultrastructural investigations of HSCs were conducted on liver bioptates from 70 children with clinicopathologically diagnosed chB before antiviral treatment. Biopsy material, fixed in paraformaldehyde and glutaraldehyde solution, was routinely processed for electron-microscopic analysis.

Results

In children with intensive liver fibrosis (S-2 and S-3), the ultrastructural picture showed almost total replacement of quiescent HSCs (Q-HSCs) by activated, i.e. transitional HSCs (T-HSCs). Among T-HSCs, two types of cells were distinguished: cells exhibiting initiation of HSC activation (Ti-HSCs), never before described in chB, that were frequently accompanied by activated Kupffer cells, and cells with features of perpetuation of activation (Tp-HSCs). Tp-HSCs were elongated and characterized by substantial loss of cytoplasmic lipid material; they contained an increased number of cytoskeletal components, extremely dilated channels of granular endoplasmic reticulum and activated Golgi apparatus, which indicated their marked involvement in intensive synthesis of extracellular matrix proteins. Many collagen fibers were found to adhere directly to Tp-HSCs.

Conclusions

The current study showed T-HSCs to be an important link between Q-HSCs and myofibroblastic HSCs (Mf-HSCs). Transformation of HSCs into new morphological variations (Ti-HSCs; Tp-HSCs and Mf-HSCs), observed along with growing fibrosis, indicates their high plasticity and a key role in fibrogenesis in pediatric chB.  相似文献   
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