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991.
Background: Pentraxin 3 (PTX3) is an acute phase reactant which has been used to detect intra-amniotic infections (IAI) in pregnancy, but the prognostic value of PTX3 concentrations on neonates has not been studied. We aimed to investigate the relationship between maternal PTX3–neonatal PTX3 concentrations and early neonatal outcome.

Methods: The mothers diagnosed with preterm prelabor rupture of membranes (PPROM) (n?=?28) and their preterm infants (n?=?28) were included in the study. PTX3 concentrations were studied in plasma in the maternal peripheral blood and umbilical/peripheral vein in the neonates. The relationship between the mPTX3–nPTX3 concentrations and neonatal outcome were investigated using non-parametric tests and binary logistic regression analysis.

Results: The mean mPTX3 concentration was 10.35?±?7.82?μg/L. Ten (35.7%) of all mothers were within the normal range and 18 (64.3%) in high percentile (≥97.5 percentile). There was no relation between mPTX3 concentrations and clinical or histologic chorioamnionitis, latency of PPROM, and early neonatal outcome. Mean nPTX3 concentrations was 9.18?±?7.83?μg/L and high nPTX3 concentrations were detected in five (17.8%) neonates. nPTX3 concentrations were inversely correlated with gestational age and correlated with rate of intraventricular hemorrhage (IVH) and mortality. Neonates with high nPTX3 concentrations also have lowered APGAR scores, increased rate of respiratory distress syndrome, clinical sepsis, IVH, necrotizing enterocolitis and prolonged NICU stay.

Conclusion: High PTX3 concentrations of the newborns are associated with some worsened early neonatal outcome including lower gestational age at delivery, increased rate of IVH and mortality. Maternal PTX3 concentrations are not an adequate marker in defining clinical or histologic chorioamnionitis and early neonatal outcome.  相似文献   

992.
Objective: To determine the utility of ultrasound (US) in late pregnancy for identifying fetuses with growth disturbances.

Methods: This study was designed as a retrospective study of birth weights over a 12-month period at the Royal Hobart Hospital (RHH) and Barwon Health (BH). Data were collected from the discharge summaries and medical records at both hospitals targeting abnormal fetal weight below 10th percentile (small for gestational age – SGA) and above 90th percentile (large for gestational age – LGA).

Results: There were 4079 study patients from both hospitals. After weight adjustment by gender and gestational age, an abnormal fetal weight was detected in 741 cases (babies over the 90th percentile or below 10th percentile). One hundred and twenty-eight patients with high-risk pregnancies were excluded. Therefore, a total of 613 patients remained that were considered to be low-risk pregnancies with abnormal foetal growth; 305 patients from RHH and 308 from BH. The antenatal detection rate for LGA was 35.9%, at RHH by combination of US and clinical evaluation, while for BH it was 34.8% by clinical evaluation alone (p?=?0.910). The antenatal detection rate for SGA was 36.8% via US and clinical evaluation at RHH and 54.5% by clinical evaluation alone at BH (p?=?0.006).

Conclusion: This study shows no benefit in the use of routine US for the antenatal diagnosis of LGA compared with clinical evaluation in low-risk pregnancies. US evaluation was inferior to clinical evaluation in the antenatal diagnosis of SGA in low-risk pregnancies.  相似文献   

993.
The distribution of alkaline phosphatase activity in human articular cartilage from normal and osteoarthritic joints has been examined by an electron microscope technique, probably for the first time. In osteoarthritic cartilage chondrocytes and matrix vesicles close to the tidemark were positive for alkaline phosphatase activity. Large numbers of matrix vesicles were found within the extracellular matrix of osteoarthritic cartilage, and there is a specific relation between phosphatase activity, matrix vesicles, and initial mineral formation in the tidemark region of articular cartilage.  相似文献   
994.

Background

Polycystic ovary syndrome (PCOS) is related to metabolic syndrome, insulin resistance, and cardiovascular metabolic syndromes. This is particularly true for individuals with central and abdominal obesity because visceral abdominal adipose tissue (VAAT) and epicardial adipose tissue (EAT) produce a large number of proinflammatory and proatherogenic cytokines. The present study aimed to determine whether there are changes in VAAT and EAT levels which were considered as indirect predictors for subclinical atherosclerosis in lean patients with PCOS.

Methods

The clinical and demographic characteristics of 35 patients with PCOS and 38 healthy control subjects were recorded for the present study. Additionally, the serum levels of various biochemical parameters were measured and EAT levels were assessed using 2D-transthoracic echocardiography.

Results

There were no significant differences in mean age (p?=?0.056) or mean body mass index (BMI) (p?=?0.446) between the patient and control groups. However, the body fat percentage, waist-to-hip ratio, amount of abdominal subcutaneous adipose tissue, and VAAT thickness were higher in the PCOS patient group than in the control group. The amounts of EAT in the patient and control groups were similar (p?=?0.384). EAT was correlated with BMI, fat mass, waist circumference, and hip circumference but not with any biochemical metabolic parameters including the homeostasis model assessment of insulin resistance index or the levels of triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein (HDL) cholesterol. However, there was a small positive correlation between the amounts of VAAT and EAT. VAAT was directly correlated with body fat parameters such as BMI, fat mass, and abdominal subcutaneous adipose thickness and inversely correlated with the HDL cholesterol level.

Conclusions

The present study found that increased abdominal adipose tissue in patients with PCOS was associated with atherosclerosis. Additionally, EAT may aid in the determination of the risk of atherosclerosis in patients with PCOS because it is easily measured.
  相似文献   
995.
996.
Two isoxazolidine derivatives namely 5-(benzo[d][1,3]dioxol-5-ylmethyl)-2-tetradecyl isoxazolidine (BDMTI) and 5-(4-hydroxy-3-methoxybenzyl)-2-tetradecyl isoxazolidine (HMBTI) were synthesized and characterized using FTIR, C-NMR, H-NMR, and elemental analysis. The synthesized compounds were evaluated as corrosion inhibitors for API 5L X60 steel in 1 M HCl in the temperature range of 25–60 °C using gravimetric and electrochemical (Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PDP) and Linear Polarization Resistance (LPR)) techniques. The effect of addition of a small amount of iodide ions on the corrosion inhibition performance of the compounds was also assessed. In addition, quantum chemical calculations and Monte Carlo simulations were employed to correlate the electronic properties of the compounds with the corrosion inhibition effect as well as to evaluate the adsorption/binding of the inhibitor molecules on the steel surface. Experimental results show that the two compounds inhibited the corrosion of carbon steel in an acid environment with HMBTI showing superior performance. The corrosion inhibition effect was found to be dependent on the inhibitors'' concentration and temperature. Addition of iodide ions improves the inhibition efficiency considerably due to co-adsorption of the iodide ions and the inhibitors on the steel surface which was competitive in nature as confirmed from the synergistic parameter (S1) which was less than unity at higher temperature. Experimental and theoretical results are in good agreement.

Two isoxazolidine derivatives (BDMTI and HMBTI) were synthesized and characterized using FTIR, C-NMR, H-NMR and elemental analysis and evaluated as corrosion inhibitors for X60 steel in 1 M HCl solution.  相似文献   
997.
A bioguided separation on the cultures of the potato endophytic fungus Bipolaris eleusines led to the isolation of two anti-phytopathogenic (Alternaria solani) sesquiterpenoid-xanthone adducts, namely bipolins I and J (1 and 2). Their structures were established via extensive spectroscopic analysis. Compounds 1 and 2 exhibit potent inhibitory activity against A. solani with MIC values of 8 and 16 μg mL−1, respectively.

Two sativene sesquiterpenoid-xanthone adducts from potato endophytic fungus Bipolaris eleusines  相似文献   
998.
A series of ether phosphonates have been prepared by trichloroacetimidate and acetate coupling methods. Trichloroacetimidates or acetates were treated with primary and secondary alcohols as O-nucleophiles in the presence of catalytic TMSOTf to afford 21 examples of diethyl alkyloxy(substitutedphenyl)methyl phosphonates via C–O bond formation in 55–90% yields and short reaction time.

An efficient method for the synthesis of various ether phosphonates by trichloroacetimidate and acetate coupling methods is described.  相似文献   
999.
Two simple, sensitive, and rapid spectrofluorimetric methods were developed and validated for the determination of albendazole. The first method (method I) was based on the quenching effect of albendazole on the native fluorescence of erythrosine B. The fluorescence intensity was measured at 554 nm after extraction at 527 nm. In the second method (method II) the drug was reacted with lanthanum(iii) ions to form a metal complex, which was measured at 340 nm after excitation at 295 nm. The suitable pH was 3.4 (Teorell–Stenhagen buffer) and pH 5.5 (phosphate buffer solution), for method I and II, respectively. The influence of experimental factors on the fluorescence intensity of the reaction products was investigated and optimized. The linear concentration ranges were 0.2–3.5 and 0.06–0.90 μg mL−1, with detection limits of 0.049 and 0.019 μg mL−1 for method I and II, respectively. ICH guidelines were followed for validation of the developed procedures, and the results were acceptable. The Gibb''s free energy change of the reactions was −24.6 and −27.5 kJ mol−1 for method I and II, respectively. These negative values indicated the high feasibility of these reactions at ambient temperature. The proposed procedures were applied successfully for the determination of albendazole in commercial dosage forms and spiked human plasma. The results showed high precision, accuracy and recovery of the reported methods without any significant interference from pharmaceutical excipients or plasma components.

Complexation of albendazole with erythrosine B quench the native fluorescence of the dye while complexation of the drug with lanthanum (iii) ions enhance the fluorescence of the drug.  相似文献   
1000.
The combination of visible-light and tris(trimethylsilyl)silane promoting intramolecular reductive cyclization protocol for the synthesis of functionalized indolines and 2,3-dihydrobenzofurans has been developed. The transformations occur in the absence of transition metal and additional photocatalyst. In addition, quantum yield (Φ) was determined and electron paramagnetic resonance spectroscopy was performed to better understand the reaction pathway.

The combination of visible-light and tris(trimethylsilyl)silane promoting intramolecular reductive cyclization protocol for the synthesis of functionalized indolines and 2,3-dihydrobenzofurans has been developed.  相似文献   
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