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91.
Aim: To compare the efficacy of 14‐day and 5‐day amoxicillin treatment on the eradication rate during tetracycline containing sequential H. pylori therapy, and also to compare the eradication rate of this regimen with those used in similar studies performed in Turkey. Method: This study included 112 patients infected with H. pylori that were randomized into 2 groups. In group A, patients (n = 56) received pantoprazole (40 mg BID) and amoxicillin (1 g BID) for 5 days, followed by pantoprazole (40 mg BID), tetracycline (500 mg QID), and metronidazole (500 mg TID) for the remaining 9 days. In group B, patients (n = 56) received pantoprazole (40 mg BID) and amoxicillin (1 g BID) for 5 days, followed by pantoprazole (40 mg BID), tetracycline (500 mg QID), metronidazole (500 mg TID), and amoxicillin (1 g BID) for the remaining 9 days. Eradication rates were calculated using both intention‐to‐treat (ITT) and per‐protocol (PP) analyses. Results: In all, 112 patients were subjected to ITT analysis and 109 patients completed the study. In group A, H. pylori eradication was achieved in 46 (82.1%) of the 56 patients included in the ITT analysis and in 46 (83.6%) of the 55 patients included in the PP analysis. In group B, H. pylori eradication was achieved in 44 (78.57%) of the 56 patients included in the ITT analysis and in 44 (81.48%) of the 54 patients included in the PP analysis ( Table 2 ). The eradication rates were not statistically significant between the 2 groups (p > .005).
Table 2. Eradication rates in the two study groups
Group A Group B p
n ITT/PP n ITT/PP
Eradication
Female 21 70%/72.4% 34 79.06%/82.9% NS
Male 25 6.1%/96.1% 10 76.9%/76.9% NS
Total 46 82.1%/83.6% 44 78.57%/81.48% NS
  • NS, not significant; PP, per‐protocol; ITT, intention‐to‐treat.
Conclusion: Extended duration of amoxicillin treatment during the entire tetracycline containing sequential therapy period did not improve the H. pylori eradication rate. As a consequence, sequential therapy using 5‐day amoxicillin is an acceptable first‐line therapy option for the eradication of H. pylori in Turkey.  相似文献   
92.
We present a protocol for building and operating a microfluidic device for mechanical immobilization of Caenorhabditis elegans in its physiologically active state. The system can be used for in vivo imaging of dynamic cellular processes such as cell division and migration, degeneration, aging and regeneration, as well as for laser microsurgery, Ca2+ imaging and three-dimensional microscopy. The device linearly orients C. elegans, and then completely restrains its motion by pressing a flexible membrane against the animal. This technique does not involve any potentially harmful anesthetics, gases or cooling procedures. The system can be installed on any microscope and operated using only one syringe and one external valve, making it accessible to most laboratories. The device fabrication begins by patterning photoresist structures on silicon wafers, which are then used to mold features in elastomeric layers that are thermally bonded to form the device. The system can be assembled within 3 d.  相似文献   
93.
94.
As the evidence of global climate change continues to mount, its consequences for cropland productivity assume particular significance. Against the backdrop of past agricultural practices, simulation models offer a glimpse into the future, showing the effect of temperature changes on crop production. In this study, we first quantified the carbon (C) and nitrogen (N) budgets of Ohios cropland ecosystems using inventory yield data of corn for grain, oat, and all wheat for the period 1866–1996 and soybean for the period 1924–96. Then we explored the responses of Ohios continuous soybean croplands to changes in temperature, carbon dioxide (CO2) concentration, initial soil organic C and N (SOC-N) pools, soil texture, and management practices by developing a simple cropland ecosystem model (CEM) and performing a long-term sensitivity analysis. Finally, CEM simulations were evaluated against independent observations of SOC values (0–19 cm) averaged over 470 northwest Ohio sites between 1954 and 1987 under conventional tillage and rotations of corn–soybean–winter wheat by using the historical yield data (r 2 = 0.8). The C contents per hectare of crop harvests increased by 178% for oats, 300% for corn for grain, and 652% for all wheat between 1866 and 1996 and by 305% for soybean between 1924 and 1996. Ohio croplands acted as C–N sources, releasing average net ecosystem emissions (NEE), including the removal of harvested C–N, of 4,598 kg CO2 ha–1 and 141 kg N ha–1 in 1886 and 205 kg CO2 ha–1 (except for the corn-for-grain cropland) and 39 kg N ha–1 in 1996. The continuous corn croplands continued to become a C sink, sequestering 255 kg C ha–1 in 1996. Results of the sensitivity analysis for Ohios continuous soybean croplands revealed that the SOC pool increased by 6.9% and decreased by 7.5% in response to a doubled CO2 concentration and a temperature increase of 2.8°C over 100 years, respectively. The sequestration potential of the SOC pool increased by 6.5% at a rate of 24.6 kg C ha–1 y–1 for the same period with finer soil texture (loam to silty clay loam). The shift from conventional to conservation residue practice led to an 11% increase in the steady-state SOC storage at a rate of 42 kg C ha–1 y–1 for 100 years.  相似文献   
95.
Doxorubicin (DXR) is a highly effective drug for chemotherapy. However, cardiotoxicity reduces its clinical utility in humans. The present study aimed to assess the ameliorative effect of curcumin against DXR‐induced cardiotoxicity in rats. Rats were subjected to oral treatment of curcumin (100 and 200 mg/kg body weight) for 7 days. Cardiotoxicity was induced by single intraperitoneal injection of DXR (40 mg/kg body weight) on the 5th day and the rats sacrificed on 8th day. Curcumin ameliorated DXR‐induced lipid peroxidation, glutathione depletion, decrease in antioxidant (superoxide dismutase, catalase, and glutathione peroxidase) enzyme activities, and cardiac toxicity markers (CK‐MB, LDH, and cTn‐I). Curcumin also attenuated activities of Caspase‐3, cyclooxygenase‐2, inducible nitric oxide synthase, and levels of nuclear factor kappa‐B, tumor necrosis factor‐α, and interleukin‐1β, and cardiac tissue damages that were induced by DXR. Moreover, curcumin decreased the expression of 8‐OHdG and 3,3′‐dityrosine. This study demonstrated that curcumin has a multi‐cardioprotective effect due to its antioxidant, anti‐inflammatory, and antiapoptotic properties.  相似文献   
96.
 Although the submandibular gland (SMG) plays important exocrine and endocrine roles, little is known about the molecular details underlying its development. Previously, we reported that in the postnatally developing hamster SMG, GPT, the protein product of the first N-glycosylation gene, ALG7, was an in vivo marker for salivary cell proliferation. Here we investigated the proliferative, cytoskeletal, and adhesive changes during SMG postnatal development. The cellular localization and abundance of GPT, filamentous actin, and β1 integrin receptor were examined using confocal microscopy and immunoblotting. In neonatal glands, high GPT levels marked extensive cell proliferation throughout the tissue. The apical regions of immature salivary cells displayed intense actin staining, while most of the β1 integrin was diffusely distributed throughout the tissue. As development proceeded, discrete regions of the gland expressed attenuated levels of GPT, an increased organization of actin to the cell cortex, and β1 integrin to the basal lamina. In the adult SMG, differentiated salivary cells displayed low levels of GPT and actin. While the abundance of β1 integrin remained unchanged throughout development, in the adult, it was found exclusively in regions where cells contact the basal lamina. These data indicate that SMG development entails regionalized cell proliferation and polarization, and that these processes are temporally and spatially coordinated with the establishment of stable cell-substratum interactions. Accepted: 26 October 1998  相似文献   
97.
The purpose of the study was to synthesize and evaluate the antimicrobial effects of two monophosphazenes, N-diphenylphosphoryl-P-triphenylmonophosphazene-II and N-di(o-tolyl)phosphoryl-P-tri(o-tolyl)monophosphazene-III on bacterial and yeast strains. The biological effects of these molecules were compared with a potential antioxidant vitamin E. According to results, the triphenyl monophosphazene-II has antimicrobial effect on all the bacterial and yeast cells, but tri(o-tolyl)monophosphazene-III has only antimicrobial effect on some bacterial cells. When the concentration of triphenyl monophosphazene-II was raised, it was observed that inhibition zone increased on the bacterial growth media. The biological effects of these molecules were compared to vitamin E in the Saccharomyces cerevisiae culture media. In 200 microg administered culture media, the cell density decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups at the end of 24 and 48 h incubation times (p<0.001,p<0.05). While the cell densities in vitamin E and tri(o-tolyl)monophosphazene-II groups decreased partly at the end of 72 h incubation time (p<0.05), its level in triphenyl monophosphazene-II group increased (p<0.01) at the same incubation time. In 1,000 microg administered culture media, cell density was not found to differ between vitamin E and control groups at the end of 24h incubation time, but it was found that the cell densities in triphenyl monophosphazene and tri(o-tolyl)monophosphazene-III groups decreased at the same incubation time (p<0.001). The cell densities in tri(o-tolyl)monophosphazene-III group and triphenyl monophosphazene-II decreased at the end of 48 h incubation time (respectively, p<0.05,p<0.001). In 200 microg administered cell pellets, while the lipid level was not found to differ between control and vitamin E, the lipid level decreased in triphenyl monophosphazene-II and tri(o-tolyl)monophospazene-III groups (respectively, p<0.001,p<0.01). In 1,000 microg administered cell pellets, it was found that the lipid level decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups (p<0.001,p<0.01).  相似文献   
98.
The comparative advantages and disadvantages of intact antibodies and single-chain Fv as immunotoxins and radioimmunoconjugates have been widely discussed but not directly compared. In this study, the in vivo properties of anti-CD19 B43 monoclonal antibody and its derived single-chain Fv (FVS191) were studied in athymic nude mice bearing CD19-positive human lymphomas. B43 mab and FVS191 were labeled with iodine-125 using iodine-beads, and immunoreactivities were determined to be 57% and 72%, respectively. Scatchard analysis showed a similar high affinity for both. The results of pharmacokinetic studies revealed that FVS191 had a rapid biphasic clearance from the circulation (T1/2α = 2.5 min, T1/2β = 3.7 h); The T1/2α and T1/2β phases of B43 mab were determined to be 0.72 h and 57 h respectively. Biodistribution studies compared the uptake of labeled antibodies by CD19-positive and by CD19-negative tumors. The peak percentages of injected dose were 5.7% at 12 h for B43 and 2.45% at 1 h for FVS191. Radiolocalization indices (RI) demonstrated tumor-specific uptake for both, but higher uptake for B43. The optimal RI was seen at 15 min for FVS191 and 6 h for B43. FVS191 was unstable in vivo, approximately 50% of the injected dose being degraded in blood in 100 min. Radioactivity detected in the urine was present mainly as the deiodinized form of FVS191. The results suggest that B43 mab is favored over FVS191 in biodistribution properties and in vivo stability. Because B43 Mab showed early tumor-specific uptake, high RI values, and favorable tissue-to-blood ratios, it is a potential candidate for radioimmunotherapy and immunotoxin therapy of B-cell leukemia and lymphoma. Received: 17 June 1997 / Accepted: 17 June 1998  相似文献   
99.
Hydrogen (H2) concentrations that were associated with microbiological respiratory processes (RPs) such as sulfate reduction and methanogenesis were quantified in continuous-flow systems (CFSs) (e.g., bioreactors, sediments). Gibbs free energy yield (ΔǴ ~ 0) of the relevant RP has been proposed to control the observed H2 concentrations, but most of the reported values do not align with the proposed energetic trends. Alternatively, we postulate that system characteristics of each experimental design influence all system components including H2 concentrations. To analyze this proposal, a Monod-based mathematical model was developed and used to design a gas–liquid bioreactor for hydrogenotrophic methanogenesis with Methanobacterium bryantii M.o.H. Gas-to-liquid H2 mass transfer, microbiological H2 consumption, biomass growth, methane formation, and Gibbs free energy yields were evaluated systematically. Combining model predictions and experimental results revealed that an initially large biomass concentration created transients during which biomass consumed [H2]L rapidly to the thermodynamic H2-threshold (≤1 nM) that triggerred the microorganisms to stop H2 oxidation. With no H2 oxidation, continuous gas-to-liquid H2 transfer increased [H2]L to a level that signaled the methanogens to resume H2 oxidation. Thus, an oscillatory H2-concentration profile developed between the thermodynamic H2-threshold (≤1 nM) and a low [H2]L (~10 nM) that relied on the rate of gas-to-liquid H2-transfer. The transient [H2]L values were too low to support biomass synthesis that could balance biomass losses through endogenous oxidation and advection; thus, biomass declined continuously and disappeared. A stable [H2]L (1807 nM) emerged as a result of abiotic H2-balance between gas-to-liquid H2 transfer and H2 removal via advection of liquid-phase.  相似文献   
100.
The objectives of the present study are to compare the phenolic profiles and biological activities of 15 citrus honey samples from three different locations in Turkey using a chemometric approach. The HPLC-DAD analysis was used to determine phenolic profiles. Nineteen phenolic compounds were identified. Gallic acid (107.14–717.04 μg/g) was recorded as the predominant compound. AF (Antalya-Finike) had the highest antioxidant activity in ABTS⋅+ (IC50: 18.01±0.69 mg/mL), metal chelating (IC50: 6.20±0.19 mg/mL) and CUPRAC (A0.50: 12.05±0.68 mg/mL) assays, while it revealed the best anti-inflammatory activity against COX-2 (17.28±0.22 %) and COX-1 (43.28±0.91 %). AM (Antalya-Manavgat) was the most active in β-carotene-linoleic acid (IC50: 10.05±0.19 mg/mL), anti-urease (38.90±0.69 %), anti-quorum sensing and antimicrobial activities. AKO1 (Adana-Kozan-1) in DPPH⋅ (IC50: 34.25±0.81 mg/mL) assay, AKU1 (Antalya-Kumluca-1) in tyrosinase inhibition activity (37.73±0.38 %) assay, AKU2 (Antalya-Kumluca-2) in AChE (10.55±0.63 %) and BChE (9.18±0.45 %) inhibition activity assays showed the best activity. Chemometric tools were applied to the phenolic compositions and biological properties. PCA and HCA ensured that 15 citrus honey samples were grouped into 3 clusters. The results showed that myricetin, kaempferol, vanillin, protocatechuic acid, rosmarinic acid, rutin, vanillic acid, gallic acid, catechin and p-hydroxyphenyl acetic acid are phenolic compounds that can be used in the classification of citrus honeys.  相似文献   
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