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161.
Vagal denervation performed in the intrathoracic region in newborn lambs leads to hypoxemia and decreased respiratory system compliance (Crs), which could result from atelectasis and/or pulmonary edema. The objective of the present study was to quantify the relative roles of alveolar derecruitment and pulmonary edema as underlying cause(s) of respiratory failure. Vagal denervation was performed in the intrathoracic region and below the recurrent laryngeal nerves in six newborn lambs within 24 h of birth, whereas six were sham operated. Pre- and postinflation Crs was measured to investigate the presence of alveolar derecruitment. Pulmonary edema was assessed with lung wet-dry-to-wet and lung tissue wet-to-dry ratios, total protein, and FITC-BSA recovery in lung tissue and bronchoalveolar lavage. Compared with that in the sham-operated animals, Crs was significantly lower in vagally denervated animals. However, postinflation, pulmonary system compliance obtained by quasi-static lung inflation and deflation to 30 cmH2O showed no significant difference between the sham-operated and denervated lambs. The lung wet-dry-to-wet and lung tissue wet-to-dry ratios, total protein, and FITC-BSA recovery in lung tissue and bronchoalveolar lavage were similar in denervated and sham-operated groups. We provide evidence that reduced lung volume and not pulmonary edema is associated with intrathoracic vagal denervation and is the likely underlying mechanism for hypoxemia and low Crs.  相似文献   
162.
Paraoxonase‐1 (PON1) is an organophosphate hydrolyzer and antiatherogenic enzyme. Due to the PON1's crucial functions, inhibitors and activators of PON1 must be known for pharmacological applications. In this study, we investigated the in vitro effects of some sulfonamides compounds on human serum PON1 (hPON1). For this aim, we purified the hPON1 from human serum with high specific activity by using simple chromatographic methods, and after the purification processes, we investigated in vitro interactions between the enzyme and some sulfonamides (2‐amino‐5‐methyl‐1,3‐benzenedisulfonamide, 2‐chloro‐4‐sülfamoilaniline, 4‐amino‐3‐methylbenzenesulfanilamide, sulfisoxazole, sulfisomidine, and 5‐amino‐2‐methylbenzenesulfonamide). IC50, Ki values, and inhibition types were calculated for each sulfonamide. 2‐amino‐5‐methyl‐1,3‐benzenedisulfonamide and 2‐chloro‐4‐sülfamoilaniline exhibited noncompetitive inhibition effect, whereas 4‐amino‐3‐methylbenzenesulfanilamide, sulfisoxazole, and sulfisomidine exhibited mixed type inhibition. On the other hand, 5‐amino‐2‐methylbenzenesulfonamide showed competitive inhibition and so molecular docking studies were performed for this compound in order to assess the probable binding mechanism into the active site of hPON1.  相似文献   
163.
In vitro effects of omeprazole, morphine sulphate, remifentanyl, ketamine and vankomycin were investigated on human red blood cell glucose-6 phosphate dehydrogenase (G-6PD) (E.C. 1.1.1.49) enzyme activity purified from human red blood cell by 2', 5'ADP-Sepharose 4B affinity gel. The obtained I50 values of omeprazole, morphine, remifentanil, ketamine and vankomycin were 3.24, 43.58, 97.6, 64.16 and 0.903 mM, respectively and the Ki constants for omeprazole, morphine and vankomycin were 8.22 +/- 2.055, 25.93 +/- 6.482, and 2.71 +/- 0.677 mM, respectively and they were non competitive inhibitors.  相似文献   
164.
Salinity stress is of great importance in arid and semi-arid areas of the world due to its impact in reducing crop yield. Under salinity stress, the amount of 1-aminocyclopropane-1-carboxylate (ACC), a precursor for ethylene production in plants, increases. Here, we conducted research under the hypothesis that isolated ACC deaminase-producing Pseudomonas fluorescens and Pseudomonas putida can alleviate the stressful effects of salinity on canola (Brassica napus L.) growth. The experiments were conducted in the Soil and Water Research Institute, Tehran, Iran. Seven experimental stages were conducted to isolate and characterize ACC deaminase-producing Pseudomonas fluorescens strains and to determine factors enhancing their growth and, consequently, their effects on the germination of canola seeds. Under salinity stress, in 14% of the isolates, ACC deaminase activity was observed, indicating that they were able to utilize ACC as the sole N-source. Bacterial strains differed in their ability to synthesize auxin and hydrogen cyanide compounds, as well as in their ACC deaminase activity. Under salinity stress, the rate of germinating seeds inoculated with the strains of ACC deaminase-producing Pseudomonas fluorescens and Pseudomonas putida, and seedling growth was significantly higher. These results indicate the significance of soil biological activities, including the activities of plant growth-promoting bacteria, in the alleviation of soil stresses such as salinity on plant growth.  相似文献   
165.
166.
Viral proteins and nucleic acids stimulate TLRs to elicit production of cytokines, chemokines, and IFNs. Because of their immunostimulatory activity, several TLR agonists are being developed as vaccine adjuvants and cancer immunotherapeutics. However, TLR signaling is modified by disease state, which could enhance or impair therapeutic efficacy. For example, in the skin of psoriasis patients, the human cationic antimicrobial peptide LL37 is highly expressed and binds to host DNA. Association with LL37 enhances DNA uptake into intracellular compartments, where it stimulates TLR9-dependent overproduction of IFNs. Polyinosinic-polycytidylic acid (poly(I:C)), an analog of viral dsRNA, is recognized by TLR3 and is currently in preclinical trials as an inducer of type I IFN. If LL37 similarly enhanced IFN production, use of poly(I:C) might be contraindicated in certain conditions where LL37 is elevated. In this study, we show that TLR3 signaling was not enhanced, but was dramatically inhibited, by LL37 or mouse cathelicidin-related antimicrobial peptide in macrophages, microglial cells, and dendritic cells. Inhibition correlated with formation of a strong complex between antimicrobial peptides and poly(I:C), which partially inhibited poly(I:C) binding to TLR3. Therefore, after injury or during existing acute or chronic inflammation, when LL37 levels are elevated, the therapeutic activity of poly(I:C) will be compromised. Our findings highlight the importance of using caution when therapeutically delivering nucleic acids as immunomodulators.  相似文献   
167.
168.
In the present study, 1000 patients with clinical suspicion of FMF were retrospectively reviewed to determine the spectrum of MEFV gene mutations by using DNA sequence analysis between September, 2008 and April, 2012. Sixteen different mutations and 55 different genotypes were detected in 618 of 1000 patients. Among 16 different mutations, R202Q (21.35%) was the most frequently observed mutation; followed by E148Q (8.85%), M694V (7.95%), M680I (2.40%), V726A (1.85%), M694I (0.95%), A744S (0.80%), R761H (0.55%), P283L (0.35%), K695R (0.20%), E230K (0.15%), L110P (0.10%), I247V (0.05%), G196W (0.05%) and G304R (0.05%). In the present study, a novel missense mutation (I247V) and a silent variant (G150G) were identified in the MEFV gene. On the other hand, P238L, G632A and G304R mutations are the first cases reported from Turkey. Our results indicated that MEFV mutations are highly heterogeneous in our study population as in other regions of Turkey and mutation screening techniques such as PCR-RFLP, amplification refractory mutation system or reverse hybridization do not adequately detect uncommon or novel mutations. Therefore, it was proven that sequence analysis of the MEFV gene could be useful for detection of rare or unknown mutations.  相似文献   
169.
When studying how HIV‐1 Nef can promote packaging of the proinflammatory transmembrane protease TACE (tumor necrosis factor‐α converting enzyme) into extracellular vesicles (EVs) we have revealed a novel tyrosine kinase‐regulated unconventional protein secretion (UPS) pathway for TACE. When TACE was expressed without its trafficking cofactor iRhom allosteric Hck activation by Nef triggered translocation of TACE into EVs. This process was insensitive to blocking of classical secretion by inhibiting endoplasmic reticulum (ER) to Golgi transport, and involved a distinct form of TACE devoid of normal glycosylation and incompletely processed for prodomain removal. Like most other examples of UPS this process was Golgi reassembly stacking protein (GRASP)‐dependent but was not associated with ER stress. These data indicate that Hck‐activated UPS provides an alternative pathway for TACE secretion that can bypass iRhom‐dependent ER to Golgi transfer, and suggest that tyrosine phosphorylation might have a more general role in regulating UPS.   相似文献   
170.

Background

Immune specific genes as well as genes regulating the formation of skin barrier are major determinants for eczema manifestation. There is a debate as to whether allergic sensitization and filaggrin gene (FLG) variants lead to eczema or FLG variants and eczema increase the risk of allergic sensitization. To investigate the time-order between eczema and allergic sensitization with respect to FLG variants, data from a large prospective study covering infancy to late adolescence were analyzed.

Methodology/Principal Findings

Repeated measurements of eczema and allergic sensitization (documented by skin prick tests) at ages 1, 2, 4, 10, and 18 years were ascertained in the Isle of Wight birth cohort (n = 1,456). Three transition periods were analyzed: age 1-or-2 to 4, 4 to 10, and 10 to 18 years. FLG variants were genotyped in 1,150 participants. Over the three transition periods, in temporal sequence analyses of initially eczema-free participants, the combined effect of FLG variants and allergic sensitization showed a 2.92-fold (95% CI: 1.47–5.77) increased risk ratio (RR) of eczema in subsequent examinations. This overall risk was more pronounced at a younger age (transition period 1-or-2 to 4, RR = 6.47, 95% CI: 1.96–21.33). In contrast, FLG variants in combination with eczema showed a weaker, but significant, risk ratio for subsequent allergic sensitization only up to 10 years of age.

Conclusions/Significance

Taking the time order into account, this prospective study demonstrates for the first time, that a combination of FLG variants and allergic sensitization increased the risk of eczema in subsequent years. Also FLG variants interacted with eczema and increased the risk of subsequent allergic sensitization, which, was limited to the younger age. Hence, early restoration of defective skin barrier could prevent allergic sensitization and subsequently reduce the risk of eczema development.  相似文献   
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