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21.
BackgroundAnesthetic management of parturients with aortic stenosis is controversial. Early studies suggest maternal mortality was related to cardiac condition and anesthetic care. In this report, management of parturients with moderate or severe aortic stenosis in two institutions is compared, and published cases are reviewed.MethodsPeripartum anesthetic management of all parturients with moderate or severe aortic stenosis who gave birth between 1990 and 2005 at our institutions, is described. Patients with mild or non-valvular aortic stenosis were excluded.ResultsThere were 12 parturients, six with moderate and six with severe aortic stenosis. Two patients with moderate aortic stenosis were New York Heart Association (NYHA) classification II, the others were asymptomatic. Five patients with severe aortic stenosis were symptomatic (NYHA classification II or III). Two patients with moderate and three with severe aortic stenosis underwent cesarean delivery; epidural anesthesia was used for two. Two patients with moderate and all with serious aortic stenosis were observed postpartum for 24 to 48 h in a high-dependency unit. There were no severe maternal or neonatal complications.ConclusionsCarefully titrated regional analgesia is usually well tolerated in patients undergoing vaginal or cesarean delivery even in the presence of severe aortic stenosis. Standard monitoring is usually adequate for vaginal delivery, but invasive monitoring may facilitate management in some patients. An arterial line allows close monitoring of systemic blood pressure. Facilities for close 24-48-h post-partum observation should be available. A multidisciplinary approach is needed.  相似文献   
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Nonalcoholic steatohepatitis (NASH) may cause progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Treatment, thus far, has been restricted to diet and weight loss, but without compelling results. In this study we aimed to evaluate the efficacy of orlistat therapy in obese patients with NASH. Fourteen obese patients with NASH underwent liver biopsy prior to and subsequent to 6 months treatment with orlistat (120 mg tid). Hepatic fat extension was graded as normal, mild, moderate, or severe. Hepatic fibrosis was scored on a scale from 0 to 4, with 0 denoting no fibrosis and 4, cirrhosis. Portal inflammation was scored as 0-3, with 0 = normal, 1 = mild, 2 = moderate, and 3 = severe inflammation. Fourteen patients had NASH associated with diabetes, hyperlipidemia, or obesity. Orlistat reduced fatty infiltration in 10 patients (70%; P<0.01), 3 of whom had normal liver fat content after treatment. Orlistat improved inflammatory activity by 2 grades in 28% and by 1 grade in 50% of patients and effected no change in 22% of patients. Five patients (35%) returned to normal inflammatory activity. Orlistat improved hepatic fibrosis by 2 grades in three patients (21%) and by 1 grade in seven patients (50%). There was no change in four patients (28%). Orlistat lowered aminotransferases levels, total cholesterol, triglycerides and low-density lipoprotein, respectively. Insulin resistance index and malonyl dialdehyde levels improved significantly after orlistat therapy, whereas HbAic remained unchanged. In conclusion, in obese patients with NASH, liver fibrosis and inflammation improved after therapy with orlistat.  相似文献   
23.
Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease affecting mainly the elderly. The subtype of the disease induced by physical agents represents a rare and, therefore, insufficiently characterized form. In the present study, we aimed to contribute to a better understanding of the pathogenetic mechanisms involved in the onset of BP induced by different trigger factors. We have retrospectively analyzed nine cases of BP. All patients were characterized based on clinical, epidemiological and immunological parameters. For each case, the trigger factor involved was specified. In addition to our retrospective analysis, a comprehensive review of the 59 published cases was conducted, regarding the involvement of trigger factor in BP, and clinical, epidemiological and immunological data were collected. In the local study, conducted on nine patients diagnosed with BP, various trigger factors were identified: contrast substance injection, surgical procedure, mechanical trauma, insect bite, thermal burn, radiotherapy and ultraviolet exposure associated with pre‐existing psoriasis. The autoantibodies from all patients were shown to activate granulocytes and induce dermal–epidermal split. Different hypotheses regarding the pathogenetic mechanism involving the trigger factors have been discussed. In regard of the pathogenetic mechanism, we believe that the most reliable hypothesis is that BP patients already have low titers of anti‐basement membrane autoantibodies which activate the granulocytes. However, more studies are needed for a better understanding of the pathogenetic mechanism of the intervention of trigger factors.  相似文献   
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Preeclampsia, the major cause of maternal morbidity and mortality in developed countries, is associated with abnormalities of placenta function due to shallow invasion of the maternal decidua by trophoblasts. Data suggest that TGF-beta may play a role in inhibiting trophoblast outgrowth or invasion, or both. We report that placental TGF-beta 3 expression is high in early pregnancy but falls at around 9 weeks' gestation. This pattern is inversely correlated with trophoblast outgrowth and fibronectin synthesis, markers of early trophoblast differentiation toward an invasive phenotype. We demonstrate that TGF-beta 3 is overexpressed in preeclamptic placentae. In contrast to control placentae, explants from preeclamptic pregnancies fail to exhibit spontaneous invasion in vitro. Significantly, antisense-induced inhibition of TGF-beta 3 expression, and inhibition of TGF-beta 3 activity with antibodies, induces the formation of columns of trophoblast cells, which migrate out of the explant into the underlying Matrigel. To our knowledge, this is the first demonstration that the hypoinvasive placental phenotype characteristic of preeclampsia can be essentially normalized in vitro by biochemical manipulation. We speculate that a failure to downregulate expression of TGF-beta 3 at around 9 weeks' gestation results in shallow trophoblast invasion and predisposes the pregnancy to preeclampsia.  相似文献   
26.
The aim of antiangiogenic agents in the treatment of age related senile macular degeneration is to destroy coroidian neoformation vessels by minimally affecting the central vision. We present a case of important central vision recovery after 3 intravitreal injections of Avastin. The therapeutic decision and patient monitoring have been made using imagistical investigations such as OCT and AFG. A modern therapeutic approach of neovascular forms of age related macular degeneration, backed up by AFG and OCT is a modern treatment method of this disabling illness which brings patients optimal functional and structural improvement.  相似文献   
27.
Left atrial (LA) strain and strain rate, determined by speckle-tracking echocardiography (STE), are reproducible indices to assess LA function. Different normal ranges for LA phasic functions have been reported. We investigated the role of the reference point (P- and R-wave), gain, and region of interest (ROI), as the major sources of variation when assessing LA function. 52 subjects were evaluated for LA conventional and STE analysis. 45 of them (46 ± 14 years, 26 men) were feasible for concomitant LA deformation, and LA phasic volumes and ejection fractions (LAEF) evaluation. First, we compared the P- and R-wave methods, for the evaluation of the LA functions. We used diastolic mitral profile to clearly delineate the time intervals for each LA function. For the P-wave method, active function was assessed from negative global strain as a difference between the strain at pre-atrial contraction and strain just before mitral valve closure (GSA-), and late diastolic strain rate (GSRL); passive function from positive strain at MVO (GSA+), and from early negative diastolic strain rate (GSRE); reservoir function from the sum of GSA? and GSA+ (TGSA), and positive strain rate at the beginning of LV systole (GSR+). For the R-wave method we used the same SR parameters. The active function was evaluated by late positive global strain (GSAC), the reservoir by positive peak before the opening of the mitral valve (TGSA), and conduit function by the difference between TGSA and GSAC (GSA+). Then, by using P-wave method, we measured all previously described parameters for different gains—minimum (G0), medium (G12), and maximum (G24), and for different ROIs—minimum (ROI0), step 1 (ROI1), and 2 (ROI2). Feasibility of the LA strain measurements was 87 %. Active LA function was similar in the absolute value (GSAC and GSA?), whereas passive and reservoir functions were significantly higher (GSA+, TGSA) with the R-wave method. Active LAEF correlated with GSA? measured by the P-wave (r = ?0.44, p = 0.002), but not with the GSAC measured by the R-wave method. Similar correlations were found for passive and reservoir LAEF with correspondent strain parameters, only with P-wave method. There were no differences between methods regarding SR indices and their correlations with correspondent LAEFs. Increase of gain from minimum to maximum overestimated all measured LA functions (all p < 0.05). Intermediary changes did not have a significant impact on the measurement of active and conduit function, but they do have on the measurement of the reservoir function. Increase of ROI from minimum to ROI2 was associated with an overestimation of all measurements of atrial functions (all p < 0.05). For all parameters, except GSR+, a decrease of atrial S and SR values from minimum ROI to step 1 was recorded. For GSA+, TGSA, GSRE a decrease of S and SR values with each ROI step was recorded. The two methods used to assess LA functions by STE do not provide similar results. The R-wave method essentially ignores negative peak, creating a positive strain for atrial contraction, and also provides higher values for the reservoir and conduit functions, by comparison with the P-wave method. Increase of gain overestimates, whereas increase of ROI underestimates all parameters of LA functions. Therefore, we suggest that P-wave as a reference point, a medium gain, and a minimum ROI should be used as the best choice for a correct assessment.  相似文献   
28.
Lately, there is a growing interest in organic photovoltaic (OPV) cells due to the organic materials’ properties and compatibility with various types of substrates. However, their efficiencies are low relative to the silicon ones; therefore, other ways (i.e., electrode micron/nanostructuring, synthesis of new organic materials, use of additives) to improve their performances are still being sought. In this context, we studied the behavior of the common organic bulk heterojunction (P3HT:PC70BM) deposited by matrix-assisted pulsed laser evaporation (MAPLE) with/without 0.3% of 1,8-diiodooctane (DIO) additive on flat and micro-patterned ITO substrates. The obtained results showed that in the MAPLE process, a small quantity of additive can modify the morphology of the organic films and decrease their roughness. Besides the use of the additive, the micro-patterning of the electrode leads to a greater increase in the absorption of the studied photovoltaic structures. The inferred values of the filling factors for the measured cells in ambient conditions range from 19% for the photovoltaic structures with no additive and without substrate patterning to 27% for the counterpart structures with patterning and a small quantity of additive.  相似文献   
29.
Ohne ZusammenfassungMit 4 Textabbildungen.  相似文献   
30.
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