全文获取类型
收费全文 | 239篇 |
免费 | 20篇 |
国内免费 | 27篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 19篇 |
妇产科学 | 3篇 |
基础医学 | 30篇 |
口腔科学 | 18篇 |
临床医学 | 44篇 |
内科学 | 59篇 |
皮肤病学 | 8篇 |
神经病学 | 3篇 |
特种医学 | 25篇 |
外科学 | 20篇 |
综合类 | 18篇 |
预防医学 | 7篇 |
药学 | 15篇 |
中国医学 | 1篇 |
肿瘤学 | 15篇 |
出版年
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 6篇 |
2016年 | 7篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 12篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 10篇 |
2009年 | 10篇 |
2008年 | 5篇 |
2007年 | 11篇 |
2006年 | 5篇 |
2005年 | 13篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 21篇 |
1997年 | 18篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 14篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 10篇 |
1985年 | 4篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
排序方式: 共有286条查询结果,搜索用时 820 毫秒
101.
Maurer AH; Millmond SH; Knight LC; Mesgarzadeh M; Siegel JA; Shuman CR; Adler LP; Greene GS; Malmud LS 《Radiology》1986,161(1):221-225
Indium-111 labeled leukocyte imaging was compared with three-phase skeletal scintigraphy as a means of determining whether osteomyelitis was complicating diabetic osteoarthropathy. Three-phase scintigraphy demonstrated increased activity in both infected and noninfected osteopathic bone, with a sensitivity of 75% and a specificity of 56% for osteomyelitis. Leukocyte imaging had the same sensitivity but was most helpful for excluding infection (specificity, 89%) when three-phase imaging could not. Abnormal leukocyte localization was seen at the primary site of infection in all cases within 4 hours after injection. Disadvantages of leukocyte imaging included long preparation time, low count rates resulting in poor spatial resolution, and absence of bone landmarks, which made it difficult to differentiate soft tissue from bone infection. 相似文献
102.
Summary— Pharmacological and molecular cloning techniques have identified six human subtypes of α-adrenoceptors which are designated α1A, α1B, α1D, α2A, α2B and α2C. At the protein level human kidney expresses predominantly α2A-adrenoceptors while other α2-adrenoceptor subtypes or α1-adrenoceptors have not been detected consistently in radioligand binding studies. However, the presynaptic receptors, which inhibit noradrenaline release in the human kidney, appear to belong to the α2C-subtype. Intrarenal infusion of the nonselective α1-adrenoceptor antagonist, phentolamine, and of the selective α2-adrenoceptor antagonist, yohimbine, but not of the selective α1-adrenoceptor antagonist, doxazosin, increase renal blood flow and renin release in hypertensive patients undergoing diagnostic renal angiography. Thus, α2- but not α1-adrenoceptors appear to mediate a tonic renal vasoconstriction and inhibition of renin release. Effects of systemically given α-adrenoceptor agonists and antagonists are difficult to interpret on a mechanistic level since direct effects in the kidney and indirect effects due to baroreflex activation and peripheral presynaptic and central sympatholytic actions may at least partially offset each other. Moreover, some of these drugs may additionally act independent of α-adrenoceptors, for example, via imidazoline recognition sits. The net result in a given subject may depend on the endogenous sympatho-adrenal tone. Thus, for each target population of interest, effects have to be described empirically for each drug. 相似文献
103.
Defects in human methionine synthase in cblG patients 总被引:6,自引:0,他引:6
Gulati S; Baker P; Li YN; Fowler B; Kruger W; Brody LC; Banerjee R 《Human molecular genetics》1996,5(12):1859-1865
104.
An antifibrin antibody (T2G1s) Fab' fragment labeled with technetium-99m was tested for its ability to produce images of fresh thrombi in dogs. In gamma camera images, all thrombi were evident by 2-4 hours after injection. Mean thrombus-to-blood and thrombus-to-muscle ratios averaged 4.0 and 69 at four hours after injection and increased to 24 and 270, respectively, by 24 hours after injection. When compared with I-125 fibrinogen injected into the same dogs, Tc-99m-antifibrin Fab' had lower absolute uptake in thrombus but higher thrombus-to-blood ratios due to a faster rate of disappearance from the blood. The primary route of excretion was through the kidneys. Tc-99m-antifibrin Fab' was highly stable in vivo, with an average of 82% of the circulating radioactivity able to bind to fibrin at 4 hours after injection. When compared with an In-111-labeled Fab fragment of antifibrin antibody 59D8, thrombus-to-blood and thrombus-to-muscle ratios were slightly higher for the Tc-99m-labeled antibody, and the blood disappearance rate was slightly faster. The absolute uptake in thrombus, however, was not significantly different, and the thrombus was visualized at about the same time after injection. These studies suggest that Tc-99m T2G1s Fab' is a potential agent for detecting thrombi in a clinical setting. 相似文献
105.
Expression of blood group A antigens in human bone marrow cells 总被引:2,自引:0,他引:2
We have studied the appearance of blood group A-activity during hematopoiesis in human bone marrow cells by the use of the blood group A-specific lectin from Vicia cracca. Cells that bound the lectin were identified using antiserum against the lectin followed by rosetting with protein A-containing Staphylococcus aureus cells. Only cells of the erythroid lineage from blood group A individuals formed staphylococcal rosettes. A-activity occurred in basophilic normoblasts and later stages of erythropoiesis, whereas pronormoblasts were negative. The appearance of blood group A-activity coincided roughly with the onset of hemoglobin synthesis and slightly later than the expression of the major sialoglycoprotein of erythrocytes, glycophorin A. Glycophorin A did not, however, contain blood group A-activity when analyzed by immunoprecipitation and gel electrophoresis. 相似文献
106.
107.
Background: Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies.
Objective: The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats.
Materials and methods: Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts ( Vf ), collagen fibers ( V cf ) and other structures ( V o ) were assessed in the region of the lower first molar.
Results: After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for Vf , V cf , and V o were similar to those of the control rats ( P > 0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the V f and V cf ( P < 0.05).
Conclusions: Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related. 相似文献
Objective: The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats.
Materials and methods: Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts ( V
Results: After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for V
Conclusions: Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related. 相似文献
108.
Background: The cementation of crowns to dental implant abutments is an accepted form of crown retention that requires consideration of the properties of available cements within the applied clinical context. Dental luting agents are exposed to a number of stressors that may reduce crown retention in vivo, not the least of which is occlusal loading. This study investigated the influence of compressive cyclic loading on the physical retention of cast crown copings cemented to implant abutments. Methods: Cast crown copings were cemented to Straumann synOcta titanium implant abutments with three different readily used and available cements. Specimens were placed in a humidifier, thermocycled and subjected to one of four quantities of compressive cyclic loading. The uniaxial tensile force required to remove the cast crown copings was then recorded. Results: The mean retention values for crown copings cemented with Panavia‐F cement were statistically significantly greater than both KetacCem and TempBond non‐eugenol cements at each compressive cyclic loading quantity. KetacCem and TempBond non‐eugenol cements produced relatively low mean retention values that were not statistically significantly different at each quantity of compressive cyclic loading. Compressive cyclic loading had a statistically significant effect on Panavia‐F specimens alone, but increased loading quantities produced no further statistically significant difference in mean retention. Conclusions: Within the limitations of the current in vitro conditions employed in this study, the retention of cast crown copings cemented to Straumann synOcta implant abutments with a resin, glass ionomer and temporary cement was significantly affected by cement type but not compressive cyclic loading. Resin cement is the cement of choice for the definitive non‐retrievable cementation of cast crown copings to Straumann synOcta implant abutments out of the three cements tested. 相似文献
109.
Five-day storage of platelets in a non-diethylhexyl phthalate- plasticized container 总被引:2,自引:0,他引:2
EL Snyder ; RH Aster ; A Heaton ; G Grode ; P Napychank ; L Kagen ; LC Jefferies ; S Hedberg ; DH Buchholz 《Transfusion》1992,32(8):736-741
A non-diethylhexyl phthalate (DEHP)-plasticized blood bag for 5-day storage of random-donor platelet concentrates has been developed. The plastic bag is composed of polyvinylchloride plastic with a butyryl trihexyl citrate plasticizer. The suitability of this plastic for the storage of platelet concentrates for use in clinical transfusion practice was evaluated. In vitro storage studies showed no significant differences at Day 5 for a series of in vitro assays (test plastic vs. control plastic) including pH (7.31 vs. 7.44), lactate dehydrogenase discharge (21.8 vs. 17.1%), pO2 (103 vs. 120 torr), osmotic recovery (52 vs. 57%), and morphology score (527 vs. 516). For paired radiolabeled recovery and survival data from autologous blood donors, results showed equivalence between the test plastic and two control plastics. A small but significant difference between test and control plastics in regard to survival was found by using a linear computer model, but not with a gamma function (multiple-hit) model. For paired transfusions to thrombocytopenic patients, the corrected count increments at 1 to 4 hours (test vs. control) were 13,534 versus 15,494 (p > 0.05, NS). Similar results were seen for corrected count increments determined at 12 to 24 hours. It can be concluded that platelets stored in the test plastic are acceptable for use in clinical practice. 相似文献
110.
Quality of measurements of acute surgical and traumatic wounds using a digital wound‐analysing tool 下载免费PDF全文
Dymmie LC Landa Anne‐Margreet van Dishoeck Ewout W Steyerberg Steven ER Hovius 《International wound journal》2016,13(5):619-624
The aim of this study was to assess the reliability of measurements using a wound‐analysing tool and their interpretability. Wound surface areas and tissue types, such as granulation, slough and necrosis, in twenty digital photographs were measured using a specific software program. The ratio of these tissue types in a wound was calculated using a wound profile. We calculated the intraclass coefficient or κ for reliability, standard error of measurement (SEM) and smallest detectable change (SDC). The inter‐rater reliability intraclass correlation coefficient (ICC) was 0·99 for surface area, 0·76 for granulation, 0·67 for slough and 0·22 for necrosis. The profiles gave an overall κ of 0·16. For test–retest reliability, the ICC was 0·99 for surface area, 0·81 for granulation, 0·80 for slough and 0·97 for necrosis. The agreement of the applied profiles in the test–retest was 66% (40–100). SEM and SDC for surface area were 0·10/0·27; for granulation, 6·88/19·08; for slough, 7·17/19·87; and for necrosis, 0·35/0·98, respectively. Measuring wound surface area and tissue types by means of digital photo analysis is a reliable and applicable method for monitoring wound healing in acute wounds in daily practice as well as in research. 相似文献