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排序方式: 共有1115条查询结果,搜索用时 15 毫秒
1.
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®.  相似文献   
2.
Experimental composites using either bisGMA/TEGDMA or UEDMA/ TEGDMA matrices, quartz or barium glass fillers, and 2 different filler silanization methods were evaluated regarding monomer leachability in distilled water. The leached amount was detected and quantified using gas chromatography. The results showed that twice as much TEGDMA is leached from a bisGMA/TEGDMA based composite than from an UEDMA/ TEGDMA based composite, when both contain 50 wt% TEGDMA. The hypothesis suggested that the higher degree of cure of UEDMA/TEGDMA based composites would be reflected in a lower monomer leaching value, and this hypothesis was supported by the findings. Whether such a correlation exists within groups of UEDMA/TEGDMA based matrices having different degrees of cure was not determined and needs to be investigated in future studies. Variables such as filler composition and silane treatment did not affect the leaching values of TEGDMA in water. That finding suggests that future studies should target differences in matrices, and that the need for considering effects of filler composition and silane treatment methods should not receive the same priority.  相似文献   
3.
The examination of monthly (or quarterly) increments in weight or length is important for assessing the nutritional and health status of children. Growth velocities are widely thought to be more important than actual weight or length measurements per se. However, there are no standards by which clinicians, researchers, or parents can gauge a child's growth. This paper describes a method for computing growth velocities (monthly increments) for physical growth measurements with substantial measurement error and irregular spacing over time. These features are characteristic of data collected in the field where conditions are less than ideal. The technique of smoothing by splines provides a powerful tool to deal with the variability and irregularity of the measurements. The technique consists of approximating the observed data by a smooth curve as a clinician might have drawn on the child's growth chart. Spline functions are particularly appropriate to describe bio-physical processes such as growth, for which no model can be postulated a priori. This paper describes how the technique was used for the analysis of a large data base collected on pre-school aged children in rural Haiti. The sex-specific length and weight velocities derived from the spline-smoothed data are presented as reference data for researchers and others interested in longitudinal growth of children in the Third World.  相似文献   
4.
The long term effects of the Unilink mechanical microvascular anastomosis in terms of anastomotic patency and histological changes in the vessel wall were evaluated in 10 rabbits. Both carotid arteries and facial veins were divided and reanastomosed with the Unilink device. At death two years later all 40 anastomoses were fully patent, with histological changes similar to those described previously after 16 weeks, that is, normal endothelial lining, but almost total atrophy of the media at the anastomotic site. The thinning of the vessel wall at the anastomosis caused neither occlusions nor aneurysms during the observation period.  相似文献   
5.
Bladder motility recordings were performed in anaesthetized rats and the effect of the peripherally active opiate agonist loperamide on urinary bladder function was studied. Regional intra-arterial administration of loperamide (0.01-2 mg kg-1) induced weak bladder contraction per se. Loperamide caused an effective dose-dependent inhibition of bladder motility induced by regional injection of the receptor agonists acetylcholine (ACh) and substance P (SP), as well as by peripheral motor nerve stimulation (PNS). Pretreatment with naloxone (0.5 mg kg-1) partially antagonized the inhibitory action of loperamide on the nerve-mediated detrusor contraction. However, the depression of the motor responses induced by the receptor agonists ACh and SP was not influenced. It is suggested that the demonstrated inhibitory effect of loperamide on bladder motility is partially mediated by peripheral opioid receptors. The main non-opioid part of the inhibition might be a direct smooth muscle action.  相似文献   
6.
beta-Cell-rich pancreatic islets were incubated for 60-120 min in the presence of 1 mM or 20 mM glucose and analysed with regard to their contents of magnesium and calcium and how these elements were distributed among subcellular fractions. The islets contained 42 mmol magnesium per kg protein with as much as 70 mmol per kg protein in the microsomal fraction. Both the total amount and intracellular distribution of magnesium remained unaffected after raising the glucose concentration of the incubation medium. The islet content of calcium was twice as high as that of magnesium, the mitochondria and secretory granules accounting for most of the calcium in the sedimentable fractions. In both organelles a substantial fraction of calcium was exchangeable as indicated from the incorporation of 45Ca during 90 min of incubation of the islets. When raising the glucose concentration to 20 mM the percentage exchange of calcium increased from 10 to 27 in the mitochondria and from 13 to 28 in the secretory granules. The glucose stimulation of 45Ca uptake was not associated with a statistically significant increase in the total amounts of calcium. However, in addition to stimulating calcium/calcium exchange, it cannot be excluded that glucose also induces a net accumulation of intracellular calcium in the beta-cells.  相似文献   
7.
Establishment and Functional Implications of B-cell Connectivity   总被引:7,自引:0,他引:7  
  相似文献   
8.
Berggren P  Matsuoka R 《Hospital pharmacy》1990,25(10):928-9, 932
The use of patient-controlled analgesia (PCA) to manage pain post-operatively is becoming increasingly popular. The potential for pharmacist involvement is larger. Traditional areas of pharmacy involvement include PCA pump evaluation and selection, choice of narcotic-analgesic to be used, education of other health care professionals on PCA use, and development of PCA protocol guidelines. Monitoring post-operative pain and adjusting the PCA dosage are not traditional areas of pharmacist involvement. The purpose of this report is to describe a protocol which allows hospital pharmacists in an inpatient setting to adjust the PCA dose so that postoperative pain relief is maximized and sedation is minimized.  相似文献   
9.
Rats were treated chronically with -methyl-p-tyrosine methyl-ester HCl (-MT) twice daily for 0–14 days. At 1 h after the (last) -MT injection, d-amphetamine sulphate was given and motor activity was measured in an ANIMEX activity meter for 4 h. Amphetamine-induced excitatory and stereotyped behaviour was scored according to a rating scale in a separate experiment. A single dose of -MT markedly reduced the activity response after amphetamine. After 1–3 days of -MT treatment, tolerance to its amphetamine-antagonistic affect started to develop, reaching a maximal degree after 7–14 days. The pattern of the amphetamine response, monophasic in control rats, became biphasic in the -MT tolerant rats with an early (at 0–1 h) and a late (2–4 h) peak of motor activity. The late peak appeared within 3 days, while the early peak appeared after 7 days of -MT treatment. The results on amphetamine-induced excitatory and stereotyped behaviour in essence agreed with the motor-activity data. It is concluded that tolerance to the amphetamine-antagonistic action of -MT is not complete. Its rate of development varies in a complex pattern, indicating the presence of more than one mechanism of tolerance.  相似文献   
10.
Pericardial tamponade caused by central venous catheters   总被引:4,自引:0,他引:4  
Three cases of pericardial tamponade caused by central venous catheters are reported. Two essential factors have been recognized. First, the catheter material should be extremely soft and remain soft. Today the best material available seems to be a silicone rubber elastomer. Polyvinylchloride or polyethylene, which is widely used, is too rigid. These materials also contain phthalate esters to soften the plastic, and these softeners are gradually washed out into the bloodstream, rendering the catheters even more rigid in time. Second, a central venous catheter should enter the venous system proximal to the shoulder. When the catheter is inserted through a vein in the arm, the tip of the catheter will be able to progress 6–10 cm farther down in the venous system by extreme movements of the arm. This occurs regularly when a patient is turned in bed and his or her arm is elevated 108 at the shoulder. The internal jugular vein and the subclavian vein are the most suitable veins for catheterization. Veins in the arm should not be used.
Résumé Trois cas de tamponade péricardique après cathétérisme veineux central sont rapportés cependant que deux causes particulières de ce type d'accident iatrogène ont été mises en évidence:-emploi d'un catheter rigide.-lieu inadéquat d'introduction de cet élément. En fait, le catheter doit Être souple et le rester, le meilleur matériaux étant représenté par le silicone. Le catheter en polyethylene largement employé est trop rigide, il contient également des éléments chimiques qui ont pour but de l'assouplir mais qui sont éliminés progressivement dans le sang.D'autre part le catheter doit Être introduit dans le système veineux a proximité de l'épaule. Quand il est mis en place au niveau du bras il peut progresser de 6 à 10 cm dans le système veineux sous l'impulsion des mouvements du membre supérieur. Ceci survient régulièrement quand le malade est retourné dans son lit et que le membre est ainsi levé à 180. La veine jugulaire interne ou la veine sous clavière représentent le meilleur lieu d'introduction du cath éter. Il ne faut jamais le mettre en place au niveau d'une veine brachiale.
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