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101.
Effects of bicuculline in vitro, and acute and chronic treatment of a subconvulsive dose of bicuculline on [3H]SR 95531 binding to discrete regions of rat brains were studied in Sprague-Dawley rats. Scatchard analysis of the binding isotherms exhibited two populations of binding sites for [3H]SR 95531 in frontal cortex, cerebellum, striatum and substantia nigra. The apparent KD for high-affinity sites was significantly increased in the frontal cortex and cerebellum in the presence of bicuculline (1 M) with no change in Bmax. In contrast, the apparent affinity for low-affinity sites was not altered in the presence of bicuculline in these regions, whereas the Bmax was significantly decreased in the cerebellum. Following acute (2 mg/kg, i.p.) or chronic (2 mg/kg, i.p. for 10 days) bicuculline treatment, [3H]SR 95531 binding was also investigated in various regions of brains. The acute bicuculline treatment did not affect the [3H]SR 95531 binding in any of the regions studied. In contrast, apparent affinity for [3H]SR 95531 was significantly decreased in low-affinity sites of all regions studied in rats treated chronically with bicuculline. The Bmax values of high and low-affinity sites were significantly increased in the cerebellum with no change in the frontal cortex, striatum and substantia nigra. The present study demonstrates that chronic bicuculline treatment decreases apparent affinity of [3H]SR 95531 binding whereas the treatment increases apparent affinity of [3H]SR 95531 and [3H]muscimol binding in the cerebellum may be due to true up-regulation of GABA binding sites, involving increased de novo synthesis of receptor protein. These results also suggest that properties of cerebellar GABAA receptors are different from those in other regions.Abbreviations used GABA -aminobutyric acid - FC frontal cortex - CB cerebellum - ST striatum - SN substantia nigra  相似文献   
102.
Aims: To determine the feasibility of formulating and aerosolizing powders containing bacteriophages KS4‐M and ΦKZ for lung delivery and treatment of pulmonary Burkholderia cepacia complex and Pseudomonas aeruginosa infections. Methods and Results: Endotoxin‐removed bacteriophages KS4‐M and ΦKZ were lyophilized in lactose/lactoferrin 60 : 40 w/w matrix and deagglomerated in a mixer mill (without beads) to formulate respirable powders. The powders were then aerosolized using an Aerolizer® capsule inhaler. Mass median aerodynamic diameter (MMAD) of this inhalable aerosol was determined using Andersen cascade impactor at 60 l min?1. Measured MMAD for both types of powders was 3·4 μm, and geometric standard deviation was 1·9–2·0. Viability of bacteriophages delivered distal to an idealized mouth‐throat replica was determined from bioassays of samples collected on filters placed after the idealized replica. As a percentage of inhaler load, amount of powder delivered distal to the mouth‐throat replica, which is a measure of lung delivery, was 33·7 ± 0·3% for KS4‐M and 32·7 ± 0·9% for ΦKZ. Titres collected downstream of the mouth throat were (3·4 ± 2·5) × 106 PFU for KS4‐M with an Aerolizer capsule load of (9·8 ± 4·8) × 106 and (1·9 ± 0·6) × 107 for ΦKZ with an Aerolizer capsule load of (6·5 ± 1·9) × 107. Conclusions: Bacteriophages KS4‐M and ΦKZ can be lyophilized without significant loss of viability in a lactose/lactoferrin 60 : 40 w/w matrix. The resulting powders can be aerosolized to deliver viable bacteriophages to the lungs. Significance and Impact of the Study: Development of lactoferrin‐based bacteriophage aerosol powders solidifies the ground for future research on developing novel formulations as an alternative to inhaled antibiotic therapy in patients with cystic fibrosis.  相似文献   
103.
LY226936, methylcarbamothoic acid-S-(4,5-dihydro-2-thiazolyl) ester, is a new compound that, when administered to obese Zucker rats, caused reduced food intake. LY226936 reduced the food consumption after a single oral dose of 50 and 100 mg/kg. On chronic oral administration to meal-fed obese (5 to 35 mg/kg. once daily) and to fed obese and lean (15 mg/kg. twice daily) Zucker rats, LY226936 reduced food intake and body weight gain for periods ranging from 40 to 48 days. The effect on both parameters was statistically significant. There is no evidence in our studies that tolerance to the actions of LY226936 developed. LY226936 decreased the consumption of both high carbohydrate and high fat diets. Food consumption of meal-fed obese Zucker rats was reduced significantly each time a single dose of 10 ugm LY226936 per rat was infused intracerebroventricularly. None of the receptors studied (mu and kappa opioid, CCK, serotonin, neuropeptide Y, galinin, N-methyl-D-aspartic acid) appeared to bind LY226936 and therefore, appear not to be involved in the depression of food intake by the obese Zucker rat.  相似文献   
104.
Acetyl CoA: deacetylcephalosporin C O-acetyltransferase, which catalyzes the final step of the biosythetic pathway to cephalosporin C, was stabilized by a buffer solution containing 7-aminocephalosporanic acid and purified over 1300-fold from Acremonium chrysogenum. The purified enzyme has a molecular weight of 55,000 as measured by gel filtration. SDS-polyacrylamide gel electrophoresis showed two subunit bands corresponding to molecular weights of 27,000 and 14,000. The enzyme has an isoelectoric point at pH 4.0 and optimum activity at pH 7.5.  相似文献   
105.
Bisphenol A [2,2-bis(4-hydoxyphenyl)propane; BPA] is an endocrine disrupter widely used in polycarbonate plastics and epoxy resins. We investigated the effects of orally administered BPA on antigen-specific responses of the naïve immune system.

BPA was orally administered to T cell receptor transgenic mice, and the antigen-specific responses of immune cells were investigated. Administered BPA moderately reduced interleukin (IL)-2, 4, and interferon (IFN)-γ secretion and increases in IgA and IgG2a production.

Additionally, it was found that orally administered BPA increased antigen-specific IFN-γ production of T cells and modified whole antigen presenting cells (APCs) to suppress antigen-specific cytokine production from T cells.

These findings suggest that BPA can augment the Th1-type responses of naïve immune systems, though the bioavailability of orally administered BPA was low in our experiments.  相似文献   
106.

Background

The present study addressed how 92% oxygen administration affects cognitive performance, blood oxygen saturation (SpO2), and heart rate (HR) of intellectually and developmentally disabled people.

Methods

Seven males (28.9 ± 1.8 years) and seven females (34.4 ± 8.3 years) with intellectual and developmental disabilities (disabled level 2.1 ± 0.5) completed an experiment consisting a 0-back task with normal air (21% oxygen) administered in one run and hyperoxic air (92% oxygen) administered in the other run. The experimental sequence in each run consisted of a 1-min adaptation phase, 2-min control phase, and 2-min 0-back task phase, where SpO2 and HR were gauged for each phase.

Results

The administration of 92% oxygen increased 0-back task performance of intellectually and developmentally disabled people, in association with increased SpO2 and decreased HR. Our results demonstrate that sufficient oxygen supply subserving cognitive functions, even as a short-term effect, could increase cognitive ability for the intellectually and developmentally disabled people.

Conclusions

It is concluded that enriched oxygen can positively affect, at least in the short-term, the working memory of those with intellectual and developmental disability.  相似文献   
107.
From an administrative perspective, this article investigates equity issues in dance education, and current challenges and opportunities for leadership in postsecondary dance programs involved in teacher education and certification. Although dance education is varied in content and environment, much is shared in terms of common goals for gender equity, curricular equity, status of dance education, and diversity in the field. The author urges dance educators and administrators to actively emphasize and act on commonly shared goals, rather than focusing on differences that have historically served to separate the field. The article provides recommendations and strategies for advocacy and development focused on enduring values of dance education rooted in art making, creativity, experimentation, and the importance of artistic expression in education.  相似文献   
108.
The cold-adapted (ca) live attenuated influenza vaccine (LAIV) strains are manufactured in embryonated hens' eggs. Recently, a clonal isolate from Madin Darby Canine Kidney (MDCK) cells was derived and characterized to assess its utility as a potential cell substrate for the manufacturing of LAIV [1]. Since MDCK cells are a transformed continuous cell line [2], and low levels of residual cellular components (DNA and protein) are found in the intermediates and final filled vaccine, we sought to characterize the uptake and clearance of MDCK DNA from tissues in order to assess theoretical risks associated with manufacturing LAIV in MDCK cell culture.In order to address this concern, MDCK DNA uptake and clearance studies were performed in Sprague Dawley rats. DNA extracted from MDCK Master Cell Bank (MCB) cells was administered via an intranasal (IN) or intramuscular (IM) route. Tissue distribution and clearance of MDCK DNA were then examined in fourteen selected tissue types at selected time points post-administration using a quantitative PCR assay specific for canine (SINE) DNA.Results from these studies demonstrate that the uptake and clearance of MDCK DNA from tissues vary depending on the route of administration. When DNA was administered intranasally, as compared to intramuscularly, detectable DNA levels were lower at all time points. Thus, the intranasal route of vaccine administration appears to reduce potential risk associated with residual host cell DNA that may be present in cell culture produced final vaccine products.  相似文献   
109.
Coffee is a globally consumed beverage. Although recent studies have suggested that coffee reduced the risk of lifestyle-related diseases, there are few studies regarding allergic response.

This study investigates the effects of orally administered coffee (91 ml/kg/d) on allergic responses using a T cell receptor (TCR)-transgenic DO11.10 mouse allergic model. Splenocytes from coffee-administered naïve mice increased antigen (Ag)-specific interleukin (IL)-12p40 secretion. When Ag sensitization and coffee administration were concurrently performed, the splenocytes from coffee-administered mice showed a decrease of IL-2 and an increase of IL-12p40 secretion. The Ag-specific cutaneous response and serum IgE level were reduced in coffee-administered mice, although, after establishing the allergy, coffee administration did not suppress the allergic reaction.

These results suggest that coffee could induce a Th1-type response of the immune system and prevent an allergy developing. Further studies on the optimum dose, cultivar differences, and roasted degree need to be undertaken.  相似文献   
110.
Endo β-1,3-glucanase IV (E.C. 3.2.1.6, endo-1,3(4)-β-d-glucanase) from Flav. dormitator var. glucanolyticae FA-5 was shown to be a glycoprotein by gel filtration and sodium dodecyl sulfate gel electrophoresis. The carbohydrate moiety was composed of 17 hexose units. The enzyme had an apparent molecular weight of 3.3 x 104, determined by gel filtration, sodium dodecyl sulfate gel electrophoresis and ultracentrifugation. The enzyme showed maximum reactivity at pH 6.0 and 6.5 for living yeast cells and laminaran, respectively. The enzyme predominantly released laminaripen-taose from a variety of linear β-1,3-glucans and showed transglucanosylation activity. The amino acid composition of the enzyme and some of its physicochemical and enzymatic properties are described.  相似文献   
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