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101.
目的:建立凝血试验移动平均数质控法。方法:用移动平均数代替算术平均数,选择凝血验凝血酶原时间(PT),活化的部分凝血激酶时间和纤维蛋白原3个项目,比较两种质控方法,同时用标准血浆作为质控。结果:当用适当的移动平滑系数时,移动平均数质控法既能排除病人标本非随机必的干扰,又能很好地反映试验前因素的影响。结论 ;移动平均数空法可用于凝血试验的实验室质控。 相似文献
102.
目的 :探讨不育男性精浆转铁蛋白 (Tf)含量与精子顶体完整性的关系。方法 :149例不育男性患者按精子密度≥ 2 0× 10 6 / ml和 <2 0× 10 6 / ml分正常精子密度组和少精子组 ,同时进行精浆 Tf和精子顶体完整率 (PIA)分析。结果 :不育男性少精子组精浆 Tf含量显著低于正常精子密度组 (P<0 .0 1) ;正常精子密度的不育男性精子 PIA<80 %组精浆 Tf含量显著低于精子 PIA≥ 80 %组 (P<0 .0 1)。结论 :正常精子密度的不育男性精子 PIA下降与精浆 Tf水平有密切的关系 相似文献
103.
烹调油烟所致大鼠肺部病变及肺S9中SOD,MDA变化 总被引:8,自引:1,他引:7
利用动式吸入烹调油烟(浓度为(43±4)mg/m3)持续染毒60天制备动物模型观察肺部病理形态改变,并通过分光光度法测试肺组织匀浆S9中的MDA、SOD,探讨其损伤机理。结果表明:COF染毒组肺组织病理形态改变以炎症改变为主,尚有肺泡上皮腺样化生、不典型腺样增生病变形成。阴性对照组有轻度间质性肺炎及轻度的上皮增生。B(a)P组肺组织炎症病变少,以鳞状上皮化生较多见。COF可使肺组织匀浆S9中MDA含量增加,SOD酶活性降低,与阴性对照组比较,差异有显著性,(P<0.05)。 相似文献
104.
In a prospective autopsy series of 39 cases of fatal drowning, the detailed dissection of the skeletal muscles of the neck,
anterior / posterior trunk and the upper extremities in layers revealed intramuscular hemorrhages of different size and shape
in 20 cases (51.3 %). Light microscopy examination showed a premortal (vital/agonal) type of muscular alteration in 7 (50
%) out of 14 macroscopical hemorrhage-positive cases. These hemorrhages and histological muscle alterations are attributed
to agonal convulsions, hypercontraction and overexertion of the affected muscle groups. As long as no cutaneous or subcutaneous
hematomas above the hemorrhages can be found, these autopsy findings (with special reference to histology) can serve as an
additional criterion concerning the differentiation of drowning and another cause of death.
Received: 31 July 1998 / Received in revised form: 31 August 1998 相似文献
105.
This study examined the effect of exercise on plasma fibrinogen concentrations with simultaneous measurements of plasma volume changes. Eight moderately active males aged 26.6±3.6 years (mean±SD) completed maximal (VO2max) and submaximal (75% VO2max for 30 minutes) exercise trials separated by 7 days. Venous blood samples were obtained at rest, immediately postexercise, and following 30 minutes of recovery. Whole blood was analysed for haematocrit and haemoglobin, while citrated plasma was assayed for fibrinogen levels. Values of haematocrit and haemoglobin before and after exercise were utilised for the estimation of plasma volume changes. Plasma volume decreased (p<0.05) immediately following both maximal (−17.7±5.1%) and submaximal (−14.3±4.1%) exercise. Exercise resulted in decreased plasma fibrinogen levels (maximal exercise: from 266.3±14.5 to 222.2±23.9 mg·dL−1; submaximal exercise: from 239.5±45.4 to 209.7±42.4 mg·dL−1) only when postexercise raw data were corrected for the contraction of plasma volume. It is concluded therefore that changes in plasma volume in response to exercise should be taken into account when interpreting exercise effects on plasma fibrinogen concentration. 相似文献
106.
K. Radon D. Nowak R. Heinrich-Ramm D. Szadkowski 《International archives of occupational and environmental health》1999,72(5):297-303
Objective: The aim of this cross-sectional study was to investigate possible acute and long-term respiratory health effects of work
at different working places in the primary aluminum industry. Method: A cross-sectional study was carried out on 78 potroom workers, 24 foundry workers, and 45 carbon-plant workers (n = 147, exposed group), and 56 control workers (watchmen, craftsmen, office workers, laboratory employees) of a modern German
prebake aluminum plant. The survey consisted of pre- and postshift spirometric and urinary fluoride measurements. Results: Potroom workers had significantly lower preshift results with regard to forced vital capacity (FVC, 99.5% versus the 107.2%
predicted; P < 0.05) and peak expiratory flow (PEF, 85.2% versus the 98.4% predicted; P < 0.01) as compared with controls. In a multiple regression model a small but significant negative correlation was found
between postshift urinary fluoride concentrations and FVC, FEV1, and PEF. Across-shift spirometric changes were observed only in FVC among carbon-plant workers (103.0 ± 13.3% predicted
preshift value versus 101.2 ± 13.6% predicted postshift value; P < 0.05). Conclusions: The results suggest that lung function impairment in the modern primary aluminum industry may be only partly due to fluoride
exposure and that working in aluminum carbon plants may cause acute lung function changes.
Received: 8 July 1998 / Accepted: 31 October 1998 相似文献
107.
Sibille M Deigat N Durieu I Guillaumont M Morel D Bienvenu J Massignon D Durand DV 《European journal of clinical pharmacology》1999,55(1):13-19
Objective: Laboratory data are key evaluation procedures for Phase I clinical pharmacology for two reasons. Firstly, laboratory data
are used within the screening process to exclude subjects with asymptomatic diseases, which could result in increased danger
to themselves or confuse interpretation of the study results. Secondly, during study implementation, safety evaluation and
in particular maximum tolerated dose determination have to be done by a case-by-case analysis, sometimes using laboratory
adverse events (LAEs). Thus, relevant limits are needed to discriminate between a usual common variation and a significant
abnormality, which is considered to be a LAE. This report presents laboratory data distribution, reference values and reference
changes and, based on previously published new methods, suggests inclusion limits at screening and laboratory adverse event
limits for analysis during study implementation.
Subjects and methods: Nine hundred and twenty-seven young healthy male volunteers were recruited in one centre (Association de Recherche Thérapeutique).
A standard screening process was carried out. Protocols were approved by the local ethics committee. Blood sampling was performed
in the same conditions. Reference values (at screening and at baseline) were determined by a non-parametric procedure selecting
2.5% and 97.5% of the distribution of data. Reference changes were also defined as the 2.5–97.5% interval of distribution
of the variations between the end of treatment and baseline. Inclusion limit and LAE limit methods of determination used had
been specified in previous articles.
Results: Detailed results of laboratory data distribution, reference values at screening and at baseline, reference changes, inclusion
limits and LAE limits are presented in tables with number of subjects, mean, median, standard deviation, minimal and maximal
values and the 2.5–97.5% interval for each laboratory parameter.
Conclusion: The key aims of this paper are to provide clinical pharmacologists with data, reference values or changes obtained in the
real conditions of Phase I study implementation, and to propose relevant limits, either for screening as inclusion limits,
or during studies as LAE limits. Thus, these data, reference values and specific limits improve the capacity to screen healthy
volunteers and to analyse LAEs during Phase I studies.
Received: 30 July 1998 / Accepted in revised form: 25 November 1998 相似文献
108.
Pierre-François Méry Patrick Lechêne Rodolphe Fischmeister 《Pflügers Archiv : European journal of physiology》1992,420(5-6):529-535
A new and inexpensive system allowing rapid and synchronized changes of solutions around a membrane patch or a cell under voltage-clamp conditions is described. Four plastic capillary tubings (OD 640 m; ID 430 m) were glued together horizontally and attached to a coil of a commercially available loudspeaker. Servo-control of the position of the coil allowed the mouth of any of the capillaries to be positioned near the pipette tip within 6 ms. A high flow speed of the test solution was crucial to achieve rapid solution exchange. At a flow speed of 5 cm/s, complete exchange of the external environment of a frog ventricular cell was achieved within 20–30 ms. The time course of solution change was found to be 3–5 times faster at the tip of an open patch pipette. To preserve the physical integrity of the cell, the cell was usually perfused by a control capillary at a slow velocity (0.2 –0.4 cm/s) and test solutions flowing out of adjacent capillaries at high velocity (4–5 cm/s) were applied to the cell only for short periods. Determination of the three-dimensional contamination profile around the mouth of the control capillary allowed the optimal conditions for the use of the system to be established and possible sources of contamination to be avoided between adjacent capillaries with unmatched flow speeds. Successive and multiple changes in external solutions could be easily synchronized with voltage-clamp depolarizations to examine the time course of the effect of drugs on voltage-operated ion channels. An example of this application is given with rapid applications of the dihydropyridine agonist (-)BayK 8644 to the L-type Ca2+ channel current in frog ventricular myocytes. 相似文献
109.
J. Stewart Cameron 《Pediatric nephrology (Berlin, Germany)》1992,6(3):292-303
All recent studies of the outcome of different forms of progressive glomerulonephritis concur that a major factor, apparently determining outcome, is the presence and severity of tubulointerstitial changes, and not the degree of glomerular alteration. Moreover, at the time of biopsy, tubulointerstitial changes correlate much better with the glomerular filtration rate. These at first surprising findings are not only useful clinically, but should make us think about our models of how progression takes place in so-called glomerular nephritides. In fact, a major tubulointerstitial infiltrate of immune-competent cells is present in all forms of progressive glomerulonephritis, and again correlates with outcome. In addition, it is now clear the tubular epithelium is capable of synthesising and secreting a number of factors important in fibrogenesis, and of displaying major histocompatibility complex class II antigens and leucocyte-adhesion molecules. Tubular cells could thus present peptides to T helper cells and amplify, or maybe even initiate, immune reactions. Finally, fibrogenesis within the kidney is at last being studied, long after studies have been performed on liver and lung. In the past, too much attention has been paid to reversible inflammation and not enough to irreversible cirrhosis of the kidney.Abbreviations used Ig
immunoglobulin, e. g. IgA, IgG, IgM etc.
- TBM
tubular basement membrane
- GBM
glomerular basement membrane
- WHO
World Health Organization
- MHC
major histocompatibility complex
- CD
cluster determinant
- NK
natural killer
- IL-1
interleukin-1
- IL-2
interleukin-2
- TNF-
tumour necrosis factor alpha
- ADCC
antibody-dependent complement mediated cytolysis
- ACE
angiotensin-converting enzyme
- m
macrophage
- ICAM-1
intercellular adhesion molecule-1
- ELAM-1
endothelial leucocyte adhesion molecule-1
- VCAM-1
vascular cell adhesion molecule-1
- LFA
leucocyte function associated molecule, e. g. LFA-1, LFA-3
- C
complement e. g. C3=third component of complement, etc.
- TGF-
transforming growth factor beta
- TGF-
transforming growth factor alpha
- PDGF
platelet derived growth factor
- PAS
periodic acid Schiff
- TCR
T cell receptor
- PTEC
proximal tubular epithelial cell
- GM-CSF
granulocyte colony stimulating factor
- M-CSF
monocyte colony stimulating factor
- FGF
fibroblast growth factor 相似文献
110.
Comparison of renal function and psychomotor performance in workers exposed to elemental mercury 总被引:10,自引:0,他引:10
H. Roels R. Lauwerys J. P. Buchet A. Bernard A. Barthels M. Oversteyns J. Gaussin 《International archives of occupational and environmental health》1982,50(1):77-93
Summary Renal function and psychomotor performance (eye-hand coordination, arm-hand steadiness) of a group of 43 workers exposed to mercury vapor were examined. Their mean age and average duration of exposure to mercury were 38 and 5 years, respectively. The results were compared with those obtained in a matched group of 47 control workers. Increased proteinuria and albuminuria were found slightly more prevalent in the Hg-exposed group than in the control workers. These results are in agreement with those found during a previous study carried out in another group of workers also exposed to elemental mercury (Bucket et al. 1980). The scores of the psychomotor tests were less satisfactory in the Hg workers than in the control workers, the arm-hand steadiness test being more discriminative than the eye-hand coordination test. Preclinical changes in psychomotor function can be detected independently of the presence of signs of renal dysfunction. No clear-cut relationships were found between the prevalence of abnormal psychomotor scores and the level of mercury in blood (HgB) or in urine (HgU). Increased prevalences of abnormal psychomotor scores seem however to occur for HgB between 1 and 2 g/100 ml and for HgU between 50 and 100 g/g creatinine. Therefore, a biologic threshold limit value of 50 g/g creatinine is proposed for urinary mercury to prevent the development of preclinical effects on the central nervous system. A similar critical HgU level based on renal dysfunction prevalences has been suggested in a previous study.This study was supported by a grant from the Commission of the European Communities 相似文献