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101.
Laser metal deposition (LMD) is one of the manufacturing processes in the industries, which is used to enhance the properties of components besides producing and repairing important engineering components. In this study, Stellite 6 was deposited on precipitation-hardened martensitic stainless steel (17-4 PH) by using the LMD process, which employed a pulsed Nd:YAG laser. To realize a favor deposited sample, the effects of three LMD parameters (focal length, scanning speed, and frequency) were investigated, as well as microstructure studies and the results of a microhardness test. Some cracks were observed in the deposited layers with a low scanning speed, which were eliminated by an augment of the scanning speed. Furthermore, some defects were found in the deposited layers with a high scanning speed and a low frequency, which can be related to the insufficient laser energy density and a low overlapping factor. Moreover, various morphologies were observed within the microstructure of the samples, which can be attributed to the differences in the stability criterion and cooling rate across the layer. In the long run, a defect-free sample (S-120-5.5-25) possessing suitable geometrical attributes (wetting angle of 57° and dilution of 25.1%) and a better microhardness property at the surface (≈335 Hv) has been introduced as a desirable LMDed sample.  相似文献   
102.
Dietary flavonoids appear to play a role in the prevention of a number of chronic diseases such as cancer and cardiovascular disease and the soy isoflavones have been the focus of particular. Consumption of soy isoflavones may reduce the risk of cardiovascular disease both through reduction in serum lipids and by the antioxidant properties. We have therefore investigate the effects of either 2.5 or 5 mg/kg B.W. doses of isoflavones on the levels of free radicals, lipids and lipoproteins in male New Zealand White rabbits. Animals were orally given 2.5 or 5 mg/kg B.W. doses of isoflavones. The tested doses were given to rabbits every other day for 13 weeks. Treatment with isoflavones caused significant (P<0.05) decrease in the concentrations of free radicals in plasma by 33% and 35%, liver by 18% and 27%, brain by 12% and 33%, testes by 40% and 21%, and kidney by 38% and 20% for 2.5 or 5 mg/kg B.W. doses, respectively, as compared to the control. On the other hand, the activity of glutathione S-transferase (GST) did not change in treated animals as compared to control. Also, results showed that isoflavones caused a significant decrease (P<0.05) in the levels of plasma total lipids (TL) by 16% and 19%, total cholesterol by 20% and 20%, triglyceride (TG) by 18% and 23%, low density lipoprotein (LDL) by 19%, 22%, very low density lipoprotein (VLDL) by 18% and 23%, and LDL:HDL ratio by 36% and 39% for 2.5 or 5 mg/kg B.W. doses, respectively, as compared to the control. While the level of high density lipoprotein (HDL) increased by 29% and 32%. The present results showed that the 5 mg/kg dose of isoflavone seemed to be related to a better plasma lipid and lipoprotein profiles and antioxidant activity.  相似文献   
103.
In this study, the effect of cholinergic agents on imipramine antinociception in mice, in the formalin test, has been investigated. Intraperitoneal (i.p.) administration of different doses of imipramine (2.5, 5, 10, 20 and 30 mg/kg) or nicotine (0.25, 0.5, 0.75 and 1 mg/kg) induced a dose dependent antinociception in both the first and second phases of the formalin test in mice. The combination of imipramine with doses of 0.5 and 0.75 mg/kg of nicotine showed a potentiated response, in both phases of the test. However, neither hexamethonium (5 and 10 mg/kg), atropine (0.25 mg/kg) or mecamylamine (0.25 mg/kg) altered the antinociception induced by imipramine. It is concluded that nicotinic receptor activation but not the cholinergic muscarinic mechanism is involved in the imipramine-induced antinociception.  相似文献   
104.
Baboons with primary or secondary exposure to Schistosoma mansoni were compared with each other over a 12-week infection period and with baseline values obtained from uninfected baboons with respect to serum levels of the hypothalamic-pituitary-adrenal (HPA) axis hormones-corticotropin-releasing hormone, adrenocorticotropic hormone, dehydroepiandrosterone sulfate (DHEA-S), and cortisol. Baboons with primary infections, when worm recovery and oviposition rates were high and hepatic schistosome egg granulomas were large, had decreasing levels of these hormones as infection progressed, compared with both uninfected and reexposed baboons. The most reduced hormone level was that of DHEA-S. Reduction of DHEA-S and cortisol levels also occurred in primary murine infections. Reexposed baboons with low worm recovery and oviposition rates and small (modulated) hepatic granulomas showed the opposite pattern: HPA axis hormone levels were maintained at, or exceeded, the baseline values of uninfected baboons. These results suggest that HPA axis hormones may play a role in regulating the establishment, maturation, and oviposition of schistosomes and the progression of schistosomiasis.  相似文献   
105.
This article reviews the technology and science of crown fracture treatment as it applies to new materials, coupled with clinical research. To achieve clinical success, dentists need to embrace new scientific concepts and update the more traditional principles of therapy. Proposed treatments are outlined, which are based on new esthetic and insoluble adhesive materials and procedures that take into consideration the integrity of pulp biology.  相似文献   
106.
BackgroundPoor PS is a negative prognostic factor for survival and a risk factor for treatment-related toxicity with standard platinum-doublet chemotherapy for advanced NSCLC. A phase II study combining erlotinib and bevacizumab for treatment of recurrent NSCLC showed encouraging efficacy and acceptable toxicity.Patients and MethodsThis single-arm phase II study evaluated erlotinib and bevacizumab as first-line therapy for newly diagnosed nonsquamous advanced NSCLC patients with Eastern Cooperative Oncology Group PS ≥ 2 or age 70 or older. Only patients eligible for bevacizumab per label were enrolled. Patients received erlotinib 150 mg orally daily and bevacizumab 15 mg/kg intravenously on day 1 every 21 days for up to 6 cycles. The primary end point was the rate of nonprogressive disease at 4 months (alternative hypothesis > 60%).ResultsTwenty-five patients were enrolled, with median age 77 years (range, 52-90 years), 44% female, 20% never- or remote-smokers. Ninety-two percent of patients enrolled had PS of 2 per investigator assessment. The rate of nonprogressive disease at 4 months was 28%. There were no complete responses, 1 patient achieved a partial response, and 11 patients (44%) experienced stable disease as best response. Rash, fatigue, and diarrhea were the most common toxicities.ConclusionThe combination of erlotinib and bevacizumab had insufficient activity in the absence of known activating epidermal growth factor receptor gene mutations to warrant study in newly diagnosed elderly or poor PS patients with nonsquamous NSCLC.  相似文献   
107.
The pathophysiology of pregnancy-induced hypertension and preeclampsia may involve abnormalities in placentation and the Fas/Fas ligand system. Hypothesizing abnormal plasma Fas and Fas ligand in pregnancy-induced hypertension, we recruited 20 hypertensive pregnant women at mean week 15 and 29 at week 30: 18 were studied at both time points. Control groups were 20 normotensive pregnant women at week 20, 29 women at week 27, and 50 nonpregnant women. sFas and sFas ligand (sFasL) were measured by enzyme-linked immunosorbent assay (ELISA). The hypertensive women had lower sFasL at both stages of their pregnancy (P < .05). There were no differences in sFas. In 18 hypertensive pregnant women, sFasL fell from week 15 to week 29 (P < .03). We conclude that sFas and sFasL is unchanged in normal pregnancy. Hypertension in pregnancy is characterized by low sFasL, and levels fall from weeks 15 to 29. This may reflect differences in placentation in the differing physiological and pathological states.  相似文献   
108.
Hypnosis has long been known to be associated with heightened control over physical processes and researchers put it under consideration because of its usage as a therapeutic tool in many medical and psychological problems. Determination of hypnosis susceptibility level is important before prescribing any hypnotic treatment. In this study different features are introduced to classify hypnotizability levels. These features were extracted from electroencephalogram (EEG) signals which were recorded from 32 subjects during hypnosis suggestion. Based on the obtained result, a method was suggested to estimate the hypnosis susceptibility level from hypnosis EEG signals instead of using traditional clinical subjective tests.  相似文献   
109.
This paper describes oral health among children in Saudi Arabia, the dental health system in the country, and some possible solutions and recommendations to improve the oral health status.  相似文献   
110.
Screening the MC4R gene showed one rare mutation p.Met215Ile in a Moroccan patient with morbid obesity, which leads to a change in the protein structure. The analysis of MC4R variants may be useful for future therapeutic approaches.  相似文献   
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