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21.
J. Alfonso Sanchez B. Sanchis Noguera M. J. Prado Del Baño A. Sabater Pons C. Saiz Sanchez P. Cortina Greus 《European journal of epidemiology》1993,9(1):33-39
The concept of avoidable cause of death serves as the basis for measuring the quality and diversity of a health care system. In this study the authors propose a new way to use this kind of mortality by combining with the concept of life expectancy to obtain what they call life expectancy free of avoidable mortality (LEFAM).This indicator was 76.9 in 1986 in Spain while life expectancy was 75.83. If these deaths were avoidable there would be a gain of 1.09 years per person born. There is an important difference between the would-be male gain of 1.76 years and the would-be female gain of 0.6. In the ecological study, LEFAM would better explain the year to year changes of the resources in the health sector, measured in terms of the human resources (R = 0.96), the hospital beds per thousand persons (R = –0.86), and would also increase the relation with other health indicators such as infant mortality rate (R = –0.98) and mortality rate (R = 0.59) as compared with life expectancy alone. 相似文献
22.
The effect of chronic subcutaneous administration of lead acetate was studied in female rabbits. The low-dose group (15 animals) received three times a week 0.10–0.20 g/kg body weight and the high-dose group (15 animals) 0.80–1.20 g/kg. The control group received the vehicle only. Concentrations of lead in blood in the low-dose group increased to ca. 400 g/l after 70 days and in the high-dose group to ca. 900 g/l after 110 days. After 7.5 months eight animals of each group were sacrificed. The remaining rabbits were kept for an additional 4 months without treatment. Blood lead concentrations decreased with a half-time of 60–70 days. During exposure the gain in body weight was lower in the high-dose group than in the control group and the low-dose group. The high-dose group developed slight anaemia and low MCV, MCH and MCHC, and basophilic stippling of erythrocytes. These effects disappeared during recovery. ALAD activity in erythrocytes was very low during exposure in both exposed groups and did not reach control values during recovery. During exposure the concentrations of ZPP and ALA-U increased, but only ALA-U returned to normal during recovery. No other effects of lead on the composition of the urine were observed. No effects were observed on plasma urea and creatinine concentrations. In the highdose group the concentration of ALAD in the liver decreased by 30%. During recovery this effect was no longer present. No effects were seen in cytochrome P-450 content or cytochrome P-450-dependent enzyme activities. Lead was mainly stored in bones, but some also in serveral soft tissues. After recovery the concentrations in soft tissues decreased to a variable degree. In the high-dose group the relative weights of heart and liver increased. These effects disappeared during recovery. At 400 g lead/l blood no adverse effects were observed that did occur at the high dose level.Part 2, dealing with the histopathology and (electron) microscopy of the kidneys is in preparation 相似文献
23.
Factor analysis, causal indicators and quality of life 总被引:1,自引:0,他引:1
Exploratory factor analysis (EFA) remains one of the standard and most widely used methods for demonstrating construct validity of new instruments. However, the model for EFA makes assumptions which may not be applicable to all quality of life (QOL) instruments, and as a consequence the results from EFA may be misleading. In particular, EFA assumes that the underlying construct of QOL (and any postulated subscales or factors) may be regarded as being reflected by the items in those factors or subscales. QOL instruments, however, frequently contain items such as diseases, symptoms or treatment side effects, which are causal indicators. These items may cause reduction in QOL for those patients experiencing them, but the reverse relationship need not apply: not all patients with a poor QOL need be experiencing the same set of symptoms. Thus a high level of a symptom item may imply that a patient's QOL is likely to be poor, but a poor level of QOL need not imply that the patient probably suffers from that symptom. This is the reverse of the common EFA model, in which it is implicitly assumed that changes in QOL and any subscales cause or are likely to be reflected by corresponding changes in all their constituent items; thus the items in EFA are called effect indicators. Furthermore, disease-related clusters of symptoms, or treatment-induced side-effects, may result in different studies finding different sets of items being highly correlated; for example, a study involving lung cancer patients receiving surgery and chemotherapy might find one set of highly correlated symptoms, whilst prostate cancer patients receiving hormone therapy would have a very different symptom correlation structure. Since EFA is based upon analyzing the correlation matrix and assuming all items to be effect indicators, it will extract factors representing consequences of the disease or treatment. These factors are likely to vary between different patient subgroups, according to the mode of treatment or the disease type and stage. Such factors contain little information about the relationship between the items and any underlying QOL constructs. Factor analysis is largely irrelevant as a method of scale validation for those QOL instruments that contain causal indicators, and should only be used with items which are effect indicators. 相似文献
24.
为探讨重复肝动脉化疗(TAE)对原发性肝癌(PHC)患者肝脏损伤的影响,对40例经3次TAE治疗的PHC患者和25例肝血管瘤患者(经1次TAE治疗)测定治疗前后透明质酸(HA),层粘连蛋白(LN),人Ⅲ型前胶原(HpcⅢ)和Ⅳ型胶原(Ⅳ·C)的含量。结果发现第2次TAE治疗后,上述4项指标TAE前后均有显著性差异(P<0.05),以第3次TAE后升高最为明显(P<0.01)。提示重复TAE治疗常可加重PHC患者的肝损害,应引起足够的重视。 相似文献
25.
Alvarez L Peris P Bedini JL Parés A Monegal A Guañabens N Mas E Aibar C Ballesta AM 《Calcified tissue international》1999,64(4):301-303
Serum tartrate-resistant acid phosphatase (TRAcP) activity is considered to be a biochemical marker of bone resorption. Recently,
a lack of specificity of collagen-related markers for assessing bone turnover has been observed in patients with chronic liver
disease. Thus, it could be of great interest to determine serum TRAcP activity in such patients. However, nonspecificity of
the analytical reaction could occur when hemolyzed, lipemic, or icteric specimens are analyzed. Therefore, we have studied
the interference caused by bilirubin in the measurement of serum TRAcP activity using the Hillmann method. The interference
was assessed in two pools of serum containing different bilirubin concentrations but with similar total AcP levels. Mixing
proportional parts of the two pools, 10 samples were also obtained. Serum activities of total AcP and TRAcP, and the concentration
of bilirubin were measured in the 10 samples. Both the actual and the expected values obtained by theoretical calculations
were compared. Serum bilirubin values of 2.4 mg/dl showed a negative interference of 15% in the determination of serum TRAcP
activity, whereas values of bilirubin higher than 10 mg/dl interfered totally with the measurement of serum TRAcP. Bilirubin
did not interfere with the total AcP determination. This study clearly shows the interference of bilirubin in the determination
of serum TRAcP. This finding should be considered when bone metabolism disorders are evaluated in jaundiced patients.
Received: 6 April 1998 / Accepted: 1 October 1998 相似文献
26.
地砷病患者部分生化指标的测定 总被引:2,自引:0,他引:2
对病区地砷病、非地砷病患者及对照组居民体内的部分生化指标进行了检测。结果表明,地砷病患者血清中的GPT活性、UN和SA含量明显高于对照组,LDH及GSHPx活性明显降低;病区非地砷病患者LDH活性、SA含量明显升高,GSHPx活性明显降低,其它各组及各指标与对照组相比无显著差异。相关分析显示,病区病人组及非病人组血中SA含量与各自尿砷水平呈正相关(r=050,r=046),GSHPx与尿砷呈负相关(r=-051,r=-048)。提示,SA和GSHPx可作为砷中毒的早期诊断指标。砷可能对接砷居民肝功、肾功产生一定影响。 相似文献
27.
Elevated erythrocyte sedimentation rate and thrombocytosis as possible indicators of active disease in Langerhans''cell histiocytosis 总被引:2,自引:0,他引:2
Langerhans' cell histiocytosis (LCH) is a disease with an unpredictable course and unpredictable reactivations. Since active disease may cause life-long sequelae, early detection of reactivation is important. The usefulness of erythrocyte sedimentation rate (ESR) and thrombocytosis as indicators of disease activity in patients with LCH were examined. The mean values for ESR and platelet count for each quarter of a year were compiled. The means of all the ESR estimates (n=76) during each quarter of a year with active disease was 21 mm h-1, with intermediate disease activity 11 mm h-1 and with resolution 7 mm h-1. The corresponding platelet count estimates (n = 139) were 433 × 109 l-1, 365 × 109 l-1 and 304 × 109 l-1, respectively. In conclusion, elevated ESR and platelet count may be clinically valuable indicators of disease activity in LCH. 相似文献
28.
镉污染对居民健康影响及因素分析 总被引:7,自引:0,他引:7
目的了解镉污染对居民健康尤其是对女性生殖健康的影响,为镉污染防制提供科学依据.方法选择福建省一铅锌矿所在地的"污染区"与"对照区",进行现场流行病学、卫生学与入户问卷调查,并进行尿镉、尿β2-微球蛋白等实验室检测.结果污染区居民健康状况比非污染区差,阳性症状、体征都较对照区多;慢性病危险因素Logistic回归分析表明,居住污染区(OR值为2.199)、中年人是患慢性病的危险因素(OR值为2.382),多吃新鲜蔬菜是保护因素(OR值为0.76);生殖功能损害影响因素的多分类有序Logistic回归模型表明,居住污染区的危险因素OR为1.36,每天多吃新鲜蔬菜是生殖功能损害的保护因素(OR值为0.55).结论镉污染对居民健康尤其是对女性生殖健康的影响应予关注.对污染区居民而言,每天多吃新鲜蔬菜、可减少镉污染对健康尤其是对女性生殖健康的影响. 相似文献
29.
Using Vignettes to Compare the Quality of Clinical Care Variation in Economically Divergent Countries 下载免费PDF全文
John W. Peabody Fimka Tozija Jorge A. Muñoz Robert J. Nordyke Jeff Luck 《Health services research》2004,39(6P2):1951-1970
Objective. To determine whether clinical vignettes can measure variations in the quality of clinical care in two economically divergent countries.
Data Source/Study Setting. Primary data collected between February 1997 and February 1998 at two Veterans Affairs facilities in the United States and four government-run outpatient facilities in Macedonia.
Study Design. Randomly selected, eligible Macedonian and U.S. physicians (>97 percent participation rate) completed vignettes for four common outpatient conditions. Responses were judged against a master list of explicit quality criteria and scored as percent correct.
Data Collection/ Extraction. An ANOVA model and two-tailed t-tests were used to compare overall scores by case, study site, and country.
Principal Findings. The mean score for U.S. physicians was 67 percent (+/−11 percent) compared to 48 percent (+/−11 percent) for Macedonian physicians. The quality of clinical practice, which emphasizes basic skills, varied greatly in both sites, but more so in Macedonia. However, the top Macedonian physicians in all sites approached or—in one case—exceeded the median score in the U.S. sites.
Conclusions. Vignettes are a useful method for making cross-national comparisons of the quality of care provided in very different settings. The vignette measurements revealed that some physicians in Macedonia performed at a standard comparable to that of their counterparts in the United States, despite the disparity of the two health systems. We infer that in poorer countries, policy that promotes improvements in the quality of clinical practice—not just structural inputs—could lead to rapid improvements in health. 相似文献
Data Source/Study Setting. Primary data collected between February 1997 and February 1998 at two Veterans Affairs facilities in the United States and four government-run outpatient facilities in Macedonia.
Study Design. Randomly selected, eligible Macedonian and U.S. physicians (>97 percent participation rate) completed vignettes for four common outpatient conditions. Responses were judged against a master list of explicit quality criteria and scored as percent correct.
Data Collection/ Extraction. An ANOVA model and two-tailed t-tests were used to compare overall scores by case, study site, and country.
Principal Findings. The mean score for U.S. physicians was 67 percent (+/−11 percent) compared to 48 percent (+/−11 percent) for Macedonian physicians. The quality of clinical practice, which emphasizes basic skills, varied greatly in both sites, but more so in Macedonia. However, the top Macedonian physicians in all sites approached or—in one case—exceeded the median score in the U.S. sites.
Conclusions. Vignettes are a useful method for making cross-national comparisons of the quality of care provided in very different settings. The vignette measurements revealed that some physicians in Macedonia performed at a standard comparable to that of their counterparts in the United States, despite the disparity of the two health systems. We infer that in poorer countries, policy that promotes improvements in the quality of clinical practice—not just structural inputs—could lead to rapid improvements in health. 相似文献
30.