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101.
Shan  Mingqiu  Jiang  Yulan  Fu  Yuanyuan  Zhou  Yongyi  Lu  Zhihui  Yu  Sheng  Yan  Hui  Liu  Chanchan  Chen  Peidong  Bao  Beihua  Zhang  Li  Wu  Qinan 《Phytochemistry Reviews》2021,20(5):991-1012
Phytochemistry Reviews - Nepeta tenuifolia (N. tenuifolia) is a common aromatic herb that is widespread in East Asia. The aerial parts and spikes can be used as the traditional phytomedicines for...  相似文献   
102.
Curcumin exhibits anti‐inflammatory and antioxidant activities. We investigated the protective effects of curcumin in a renal injury rat model under dry‐heat conditions. We divided Sprague‐Dawley rats into four groups: dry‐heat 0‐ (normal temperature control group), 50‐, 100‐, and 150‐minute groups. Each group was divided into five subgroups (n = 10): normal saline (NS), sodium carboxymethylcellulose (CMCNa), and curcumin pretreated low, medium, and high‐dose (50, 100, and 200 mg/kg, respectively) groups. Compared to the normal temperature group, serum creatinine, blood urea nitrogen, urinary kidney injury molecule‐1, and neutrophil gelatinase‐associated load changes in lipoprotein (NGAL) levels were significantly increased in the dry‐heat environment group (P < .05); inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) expression and malondialdehyde (MDA) and related inflammatory factor levels were increased in the kidney tissue. Superoxide dismutase (SOD) and catalase (CAT) levels were decreased. However, following all curcumin pretreatment, the serum levels of kidney injury indicators and NGAL were decreased in the urine compared to those in the NS and CMCNa groups (P < .05), whereas renal SOD and CAT activities were increased and MDA was decreased (P < .05). Renal tissues of the 150‐minute group showed obvious pathological changes. Compared to the NS group, pathological changes in the renal tissues of the 100‐ and 200‐mg/kg curcumin groups were significantly reduced. Furthermore, iNOS and COX‐2 expression and inflammatory factor levels were decreased after curcumin treatment. Curcumin exerted renoprotective effects that were likely mediated by its antioxidant and anti‐inflammatory effects in a dry‐heat environment rat model.  相似文献   
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Lyme disease (LD) is one of the most important vector-borne diseases worldwide. However, there is limited information on the prevalence and risk analysis using correlated factors in the tropical areas. A total of 1583 serum samples, collected from five hospitals of Hainan Province, were tested by immunofluorescence assay (IFA) and western blot (WB) analyses using anti-Borrelia burgdorferi antibodies. Then, we mapped the distribution of positive rate (by IFA) and the spread of confirmed Lyme patients (by WB). Using ArcGIS, we compiled host-vector-human interactions and correlated data as risk factor layers to predict LD risk in Hainan Province. There are three LD hotspots, designated hotspot I, which is located in central Hainan, hotspot II, which contains Sanya district, and hotspot III, which lies in the Haikou-Qiongshan area. The positive rate (16.67% by IFA) of LD in Qiongzhong, located in hotspot I, was higher than that in four other areas. Of confirmed cases of LD, 80.77% of patients (42/52) whose results had been confirmed by WB were in hotspots I and III. Hotspot II, with unknowed prevalence of LD, need to be paid more attention considering human-vector interaction. Wuzhi and Limu mountains might be the most important areas for the prevalence of LD, as the severe host-vector and human-vector interactions lead to a potential origin site for LD. Qiongzhong is the riskiest area and is located to the east of Wuzhi Mountain. In the Sanya and Haikou-Qiongshan area, intervening in the human-vector interaction would help control the prevalence of LD.  相似文献   
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Interleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms. The study subjects included nineteen CHC patients who were grouped by viral load (low, < 106 RNA copies/ml, n = 8; high, > 106 RNA copies/ml, n = 11). The peripheral frequency of HCV-specific IL-21+CD4+ T cells was higher in the low viral load group and was negatively correlated with the serum HCV RNA viral load in all CHC patients. Meanwhile, IL-21+ cells accumulated in the liver in the low viral load group. In vitro, IL-21 treatment increased the expression of proliferation markers and cytolytic molecules on HCV-specific CD8+ T cells. In summary, these findings suggest that HCV-specific IL-21+CD4+ T cells might contribute to HCV control by rescuing HCV-specific CD8+ T cells in CHC patients.  相似文献   
107.
This work is concerned with the lubrication analysis of artificial knee joints, which plays an increasing significant role in clinical performance and longevity of components. Time-dependent elastohydrodynamic lubrication analysis for normal total knee replacement is carried out under the cyclic variation in both load and speed representative of normal walking. An equivalent ellipsoid-on-plane model is adopted to represent an actual artificial knee. A full numerical method is developed to simultaneously solve the Reynolds and elasticity equations using the multigrid technique. The elastic deformation is based on the constrained column model. Results show that, under the combined effect of entraining and squeeze-film actions throughout the walking cycle, the predicted central film thickness tends to decrease in the stance phase but keeps a relatively larger value at the swing phase. Furthermore, the geometry of knee joint implant is verified to play an important role under its lubrication condition, and the length of time period is a key point to influence the lubrication performance of joint components.  相似文献   
108.
The present study evaluated the efficacy of intracoronary administration of verapamil to attenuate the no-reflow phenomenon following the primary percutaneous coronary intervention (PCI) in patients with the ST-segment elevation acute myocardial infarction (STEMI). A total of 201 patients with STEMI who underwent primary PCI within 12 h from the beginning of the heart attack were included. The no-reflow phenomenon was defined as substantial coronary anterograde flow of TIMI ≤2. Verapamil (100–200 μg) was injected into coronary artery immediately after no-reflow; the coronary arteriography was repeated later. Hundred and ninety-eight patients with STEMI successfully underwent primary PCI, and 246 stents were implanted with the average of 1.2 stents per patient. No-reflow occurred in 25 out of 198 patients (12.6 %). Twenty-one (84 %) patients developed the flow of TIMI ≥3 after intracoronary administration of verapamil, as revealed by repeated coronary angiography. Two patients developed transient hypotension which normalized without treatment within 3–5 min. Three patients showed sinus bradycardia, in one patient there was transient II sinoatrial block, and one patient developed type 1 atrioventricular block. All adverse effects were alleviated after intravenous injection of atropine (0.5–1 mg). In conclusion, the no-reflow phenomenon following primary PCI in patients with STEMI is significantly improved by intracoronary administration of verapamil which is useful to reduce cardiovascular events during operation.  相似文献   
109.
A novel, sensitive and rapid CL method coupled with high‐performance liquid chromatography separation for the determination of carbamazepine is described. The method was based on the fact that carbamazepine could significantly enhance the chemiluminescence of the reaction of cerium sulfate and tris(2,2‐bipyridyl) ruthenium(II) in the presence of acid. The chromatographic separation was performed on a Kromasil® (Sigma‐Aldrich) TM RP‐C18 column (id: 150 mm × 4.6 mm, particle size: 5 µm, pore size: 100 Å) with a mobile phase consisting of methanol–water‐glacial acetic acid (70:29:1, v/v/v) at a flowrate of 1.0 mL/min, the total analysis time was within 650 s. Under optimal conditions, CL intensity was linear for carbamazepine in the range 2.0 × 10?8 ~ 4.0 × 10?5 g/mL, with a detection limit of 6.0 × 10?9 g/mL (S/N = 3) and the relative standard detection was 2.5% for 2.0 × 10?6 g/mL (n = 11). This method was successfully applied to the analysis of carbamazepine in human urine and serum samples. The possible mechanism of the CL reaction is also discussed briefly. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
110.
Experiments were conducted to investigate and control pollutant emission from incineration of Sedum plumbizincicola plants on a laboratory scale using an entrained flow tube furnace. Without control technologies, the flue gas contained 0.101 mg Nm?3 of Cd, 46.4 mg Nm?3 of Zn, 553 mg Nm?3 of NOx, 131 pg Nm?3 of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/Fs) and 35.4 mg Nm?3 of polycyclic aromatic hydrocarbons (PAHs). In pollutants control experiments. Al2O3, CaO, and kaolin were compared as adsorbents and activated carbon was used as an end-of-pipe method for the capture of pollutants. Kaolin, the most effective of the three adsorbents, removed 91.2% of the Cd in flue gas. While 97.6% of the Cd and 99.6% of the PAHs were removed by activated carbon. Incineration may therefore be regarded as a viable option for the safe disposal of the biomass of the zinc and cadmium hyperaccumulator species S. plumbizincicola.  相似文献   
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