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31.
Spices and herbs are extensively used in indigenous diets in tropical regions where prevalence of iron deficiency is still high. They are rich in polyphenolic compounds that are expected to inhibit iron absorption by forming iron complexes in the intestine, making dietary iron less available for absorption. The effects of six spices and herbs (chili pepper, garlic, 'Pak kyheng' (Thai leafy vegetable), shallot, tamarind, turmeric) and one mixture of spices (curry paste) on iron availability were determined by measuring the percentage dialyzable iron after addition of spices and herbs to a rice meal after simulated digestion. All tested spices and herbs contained from 0.5 to 33 mg polyphenol per meal and were potent inhibitors of iron availability (20-90%), reducing iron availability in a dose-dependent manner--with the exception of tamarind, which at 11 mg polyphenol per meal enhanced iron availability. Our findings demonstrate that culinary spices and herbs can play an important role in iron nutrition.  相似文献   
32.
Preparation of acrylic grafted chitin for wound dressing application   总被引:1,自引:0,他引:1  
Chitin grafted with poly(acrylic acid) (chitin-PAA) was prepared with the aim of obtaining a hydrogel characteristic for wound dressing application. The chitin-PAA films were synthesized at various acrylic acid feed contents to investigate its effect on water sorption ability. Acrylic acid (AA) was first linked to chitin, acting as the active grafting sites on the chain that was further polymerized to form a network structure. The evidences of grafting were found from FTIR and solid state 13C NMR spectra. The TGA results exhibited the high degradation temperature of the grafted product suggesting the formation of a network structure. The degree of swelling (DS) of chitin-PAA films was found in the range of 30-60 times of their original weights depending upon the monomer feed content. The chitin-PAA film with 1:4 weight ratio of chitin:AA, possessed optimal physical properties. The cytocompatibility of the film was investigated with a cell line of L929 mouse fibroblasts. The morphology and behavior of the cells on the chitin-PAA film were determined after different time periods of culture up to 14 days. The L929 cells proliferated and attached well onto the film. These results suggested that the 1:4 chitin-PAA has a potential to be used as a wound dressing.  相似文献   
33.
Myocardial siderosis is known as the major cause of death in thalassemia major(TM) patients since it can lead to iron overload cardiomyopathy.Although this condition can be prevented if timely effective intensive chelation is given to patients,the mortality rate of iron overload cardiomyopathy still remains high due to late detection of this condition.Various direct and indirect methods of iron assessment,including serum ferritin level,echocardiogram,non-transferrin-bound iron,cardiac magnetic resonance T2*,heart rate variability,and liver biopsy and myocardial biopsy,have been proposed for early detection of cardiac iron overload in TM patients.However,controversial evidence and limitations of their use in clinical practice exist.In this review article,all of these iron assessment methods that have been proposed or used to directly or indirectly determine the cardiac iron status in TM reported from both basic and clinical studies are comprehensively summarized and presented.Since there has been growing evidence in the past decades that cardiac magnetic resonance imaging as well as cardiac autonomic status known as the heart rate variability can provide early detection of cardiac involvement in TM patients,these two methods are also presented and discussed.The existing controversy regarding the assessment of cardiac involvement in thalassemia is also discussed.  相似文献   
34.
An open-label, non-comparative study was performed in the Department of Otolaryngology, Siriraj Hospital, Bangkok, Thailand, to assess the safety, tolerability, acceptability and efficacy of an oral polyvalent bacterial lysate (Luivac) in the treatment of recurrent respiratory tract infections (RTIs) in Thai patients. Thirty-three patients were included in this study, 18 males and 15 females, with a mean age of 34.0 +/- 14.7 years. The mean number of RTIs during the 12-month period preceding the study was 9.5 per patient. During the study each patient received one tablet of Luivac daily for 28 days followed by a treatment-free period of 28 days. This was followed with another 28 days on Luivac, after which there was a 28-day treatment-free follow-up period. This study lasted 4 months with five scheduled patient visits (V1-V5). Laboratory studies were done at baseline (V1) and after treatment (V4), which included complete blood count and serum immunoglobulins (IgA, IgE, IgG and IgM). The incidence of all adverse events was 15.2% and no case was related to the studied drug. There were no clinical relevant changes in laboratory parameters after treatment. The reduction rate of RTIs per month at the end of the study period was 63.5% when compared to the average RTIs rate per month during the 12 months preceding the study. A comparison of the first study period (V1-V3) and the second study period (V3-V5) showed a reduction in duration of RTIs (23.1%), in the clinical infection score (17.5%), in the number of antibiotics used (2.1%), in the number of symptomatic treatments (3.5%), and in the number of days absent from school or work (50.0%). Overall tolerability and acceptability were assessed as very good and good in 96.8% of the patients. This study suggests that oral polyvalent bacterial lysate (Luivac) was safe and also showed a tendency to be effective in preventing RTIs in Thai patients with or without risk factors for recurrent RTIs. Other clinical advantages were reduction in the severity and duration of infection as well as in reduction of the cost of treatment and the number of days absent from school or work.  相似文献   
35.
Delta(9)-tetrahydrocannabinol (THC) inhibits several immunologic functions of macrophages. THC's impact on peritoneal macrophages to deliver costimulatory signals to a helper T cell hybridoma was investigated by T cell interleukin-2 production stimulated with immobilized anti-CD3 antibody. The drug's inhibition of costimulatory activity depended on the macrophages. THC decreased costimulation provided by peritoneal cells elicited with polystyrene beads and thioglycollate, but the drug had no influence with macrophages elicited with thioglycollate alone. Bead administration induced CB2 mRNA expression in macrophages, while CB1 mRNA was not detected. Although inhibition was associated with functional heat-stable antigen, a costimulatory molecule, on macrophages, THC exposure did not alter cell surface heat-stable antigen expression. Inhibition by THC and anti-heat-stable antigen antibody was not additive suggesting the inhibitory mechanisms may overlap. Cannabinoid suppression was stereoselective; low affinity synthetic isomer CP56,667 did not diminish the T cell response. CB1-selective antagonist SR141716A completely reversed, and CB2-selective antagonist SR144528 partially blocked THC's inhibition. Both antagonists appeared to behave as inverse agonists in a receptor-selective manner. Although T cells expressed a low level of CB2 mRNA, neither THC nor SR141716A affected T cell activation in a system independent of macrophages, while SR144528 was inhibitory. High affinity synthetic agonist CP55,940, but not partial agonist THC, impaired costimulation by macrophages from mice lacking CB2 receptor. Although CB1 mRNA was not detected in CB2 null macrophages, CP55,940 reversed the inverse agonist activity of SR141716A. Hence, CB2 and possibly another receptor subtype may be involved in mediating cannabinoid suppression of macrophage costimulation.  相似文献   
36.
BACKGROUND: Ventricular fibrillation (VF) can be induced when a strong shock is delivered during the vulnerable period of a cardiac cycle. VF, however, cannot be induced if the shock strength is increased to the "upper limit of vulnerability" (ULV) level. Docosahexaenoic acid (DHA) has been shown to prevent the occurrence of VF after coronary occlusion. However, its effects on the ULV have not been verified. We tested the hypothesis that ULV shock strength is decreased after DHA administration. METHODS: In 10 pigs, 10 S1s (square, 5-ms) were delivered from the RV apex electrode at 300 ms cycle length. Shocks (S2, biphasic) were delivered from the RV-SVC electrodes after the last S1. The ULV was determined using an up/down protocol. In group 1 (n = 5), after the control ULV was determined at the beginning of the study, a solution containing 1.0 gm of DHA was infused intravenously within 90 min. The ULV (DHA-ULV) was determined again after the end of infusion. In group 2 (n = 5), the vehicle for DHA was infused instead of DHA to confirm that the vehicle did not have an effect on the ULV. RESULTS: DHA-ULV (412 +/- 58 V, 12 +/- 3 J) was significantly decreased (P < 0.04) compared to the control ULV (478 +/- 32 V, 16 +/- 3 J). The ULV before (483 +/- 28 V, 16 +/- 1 J) and after (463 +/- 28 V, 15 +/- 2 J) the vehicle infusion was not different (P = 0.4). There was no change in the systolic blood pressure as well as heart rate in both groups. CONCLUSION: DHA significantly decreases the ULV (13% by voltage and 25% by energy), suggesting that DHA can help to prevent VF induced by a strong stimulus delivered during the vulnerable period.  相似文献   
37.
BACKGROUND AND OBJECTIVES: Total-knee replacement (TKR) surgery is one of the most painful orthopedic procedures after surgery. Opioid has been commonly combined with a local anesthetic to improve the quality of pain relief, but the treatment has opioid-related side effects. This study compared the cost effectiveness of patient-controlled epidural analgesia (PCEA) with 0.0625% bupivacaine plus fentanyl (BF) 3 microg/mL versus 0.15% ropivacaine alone (R) during the first 48 hours after TKR procedure. METHODS: This prospective randomized double-blinded study was performed on 70 patients who underwent unilateral TKR procedure and received either BF or R after surgery. Visual analog scale (VAS) pain score at rest and upon movement, side effects, and cost of treatment were compared. RESULTS: Overall pain at rest and upon movement between groups was not significantly different (P = 0.58, 95% CI = 4.4 to -7.8 and P = 0.8, 95% CI = 6.4 to -8.2, respectively). Patients in the BF group experienced more pruritus and had more vomiting episodes than those in the R group (P = .015), whereas no difference occurred in other side effects. Nevertheless, patient satisfaction with pain management was higher in the BF group compared with that in the R group. In addition, pain treatment with bupivacaine and fentanyl was 18% less costly compared with ropivacaine alone. CONCLUSIONS: Considering the economic evaluation, we conclude that PCEA with 0.0625% bupivacaine plus fentanyl 3 microg/mL is more cost effective and provides more patient satisfaction than PCEA with ropivacaine alone. However, use of epidural ropivacaine alone causes fewer opioid-related side effects, particularly pruritus and vomiting.  相似文献   
38.
Bupivacaine lipospheres were prepared as a parenteral sustained-release system for post-operative pain management. Bupivacaine free base was incorporated into micron-sized triglyceride solid particles coated with phospholipids, which were formed via a hot emulsification and cold resolidification process. The bupivacaine liposphere dispersions were characterized with respect to drug loading, particle-size distribution, and morphology. Gelation of the fluid liposphere dispersions was observed at different time intervals upon storage. The type of phospholipids used in the formulation was found to have a major impact on the gelation of the dispersion. The use of synthetic phospholipids instead of the natural phospholipids in the formulation yielded bupivacaine liposphere dispersions exhibiting prolonged gelation time. The addition of a hydrophilic cellulosic polymer can further improve the physical stability of the dispersion.  相似文献   
39.

Background  

The Perceived Impact of Problem Profile (PIPP) was developed to provide a tool for measuring the impact of a health condition from the individual's perspective, using the ICF model as a framework. One of the aims of the ICF is to enable the comparison of data across countries, however, relatively little is known about the subjective experience of disability in middle and low-income countries. The aim of this study was to assess the validity of the Perceived Impact of Problem Profile (PIPP) for use among adults with a disability in Thailand using Rasch analysis.  相似文献   
40.

Objective

To compare red (635 nm) and infrared (780 nm) light for recording pulpal blood flow from human premolar teeth.

Design

Recordings were made from 11 healthy teeth in 9 subjects (aged 16–30 years) using a laser Doppler flow meter (Periflux 4001) equipped with both red and infrared lasers. Average blood flow signals were obtained with both light sources alternately from each tooth under five conditions: intact tooth without opaque rubber dam, intact tooth with dam, after injecting local anaesthetic (3% Mepivacaine) (LA) over the apex of the tooth and cavity preparation to almost expose the pulp, after removal and replacement of the pulp, and with the root canal empty.

Results

With infrared light, the dam significantly decreased the mean blood flow by 80%. Injecting LA and cavity preparation had no significant effect. Removal and replacement of the pulp reduced the mean blood flow by 58%. There was no further change when the pulp was removed. With red light, the dam reduced the signal from intact teeth by 60%. Injecting LA and cavity preparation had no significant effect. The signal fell by 67% after pulp removal and replacement and did not change significantly when the pulp was removed.

Conclusions

Opaque rubber dam minimises the contribution of non-pulpal tissues to the laser Doppler signal recorded from premolars. Using dam, the pulp contributed about 60% to the blood flow signal with both red and infrared light. The difference between them in this respect was not significant.  相似文献   
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