全文获取类型
收费全文 | 5097篇 |
免费 | 127篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 118篇 |
儿科学 | 226篇 |
妇产科学 | 139篇 |
基础医学 | 636篇 |
口腔科学 | 143篇 |
临床医学 | 626篇 |
内科学 | 874篇 |
皮肤病学 | 336篇 |
神经病学 | 266篇 |
特种医学 | 60篇 |
外科学 | 433篇 |
综合类 | 93篇 |
一般理论 | 1篇 |
预防医学 | 754篇 |
眼科学 | 61篇 |
药学 | 394篇 |
中国医学 | 1篇 |
肿瘤学 | 65篇 |
出版年
2017年 | 15篇 |
2015年 | 29篇 |
2014年 | 25篇 |
2013年 | 46篇 |
2012年 | 67篇 |
2011年 | 59篇 |
2010年 | 103篇 |
2009年 | 108篇 |
2008年 | 51篇 |
2007年 | 75篇 |
2006年 | 66篇 |
2005年 | 44篇 |
2002年 | 18篇 |
2001年 | 23篇 |
2000年 | 17篇 |
1999年 | 42篇 |
1998年 | 70篇 |
1997年 | 175篇 |
1996年 | 173篇 |
1995年 | 164篇 |
1994年 | 150篇 |
1993年 | 116篇 |
1992年 | 89篇 |
1991年 | 88篇 |
1990年 | 87篇 |
1989年 | 104篇 |
1988年 | 96篇 |
1987年 | 92篇 |
1986年 | 78篇 |
1985年 | 58篇 |
1984年 | 57篇 |
1983年 | 59篇 |
1982年 | 57篇 |
1981年 | 46篇 |
1980年 | 34篇 |
1979年 | 28篇 |
1978年 | 29篇 |
1977年 | 25篇 |
1976年 | 26篇 |
1975年 | 33篇 |
1973年 | 14篇 |
1972年 | 16篇 |
1959年 | 198篇 |
1958年 | 388篇 |
1957年 | 362篇 |
1956年 | 400篇 |
1955年 | 391篇 |
1954年 | 386篇 |
1949年 | 96篇 |
1948年 | 77篇 |
排序方式: 共有5226条查询结果,搜索用时 15 毫秒
91.
P. J. VAN DEN BROEK F. A. M. DEHUE P. C J. LEIJH M. TH. VAN DEN BARSELAAR R. VAN FURTH 《Scandinavian journal of immunology》1982,15(5):467-473
The usefulness of lysostaphin for the removal of cell-adherent and extracellular bacteria in assays performed to measure the intracellular killing of Straphylococcus aureus by granulocytes was investigated. The results showed that the adherence of lysosiaphin to the granulocyte surface is effectuated by a temperature-independent process and that bound lysostaphin is still microbicidal. Lysosiaphin also penetrates into the granulocytes by a temperature dependent process and kills ingested S. aureus intracellularly. Therefore, despite reports to the contrary in the literature, lysosiaphin is not a reliable agent for the removal of only extracellular S. aureus and should no longer be used in assays to determine the rate of intracellular killing by granulocytes. 相似文献
92.
Mite antigen in house dust: relationship with different housing characteristics in the Netherlands 总被引:14,自引:0,他引:14
R. T. VAN STRIEN A. P. VERHOEFF B. BRUNEKREEF J. H. VAN WIJNEN 《Clinical and experimental allergy》1994,24(9):843-853
As part of a case-controlled study on the relationship between home dampness and respiratory symptoms of children, the concentration of the major allergen of Dermato-phagoides pteronyssinus (Der p I) in floor dust and mattress dust in 516 dwellings in the Netherlands was measured. A checklist, completed by the investigators, was used to obtain information on home and occupant characteristics, which may have an impact on the Der p I concentration in house dust. The geometric mean mite antigen concentrations were 2370 ng Der p I/g floor dust for the living room, 2201 ng Der p I/g floor dust for the bedroom and 5075 ng Der p I/g mattress dust. In 86% of the houses the maximum concentration was higher than 2000 ng Der p I/g dust, that is regarded as representing a risk for genetically predisposed individuals for the development of specific IgE to house dust mite allergen. In 55% of the houses the maximum concentration exceeded 10000 ng Der p I/g dust, regarded as a risk factor for acute attacks of asthma for mite allergic patients. The Der p I concentrations in dust from carpeted floors were six to 14 times higher than in dust from floors with a smooth floor covering. Higher Der p I concentrations in floor dust were also significantly associated with increasing age of the dwelling and of the floor covering, with an increasing number of occupants, and with the absence of floor insulation. For mattress dust, the age of the mattress, the presence of an outer cavity wall and mechanical ventilation were important factors. Older mattresses had higher levels, and mattress dust from bedrooms with solid brick outer walls had higher levels than that from bedrooms with outer cavity walls. Mattresses in homes with continuous mechanical ventilation had almost twice lower levels than mattresses in homes with natural ventilation. There was a tendency towards higher Der p I concentrations in dust in homes with reported or observed signs of dampness. The Der p I concentrations in dust from carpeted bedroom floors and mattresses were positively associated with the average relative humidity in the bedroom over a period of 3–6 weeks in a subset of the homes where relative humidity was measured. Similar results were obtained using the concentrations of Der p I in ng/m2 instead of ng/g dust. The results obtained in this study are of importance for planning and evaluating allergen avoidance measures advised to mite allergic patients. 相似文献
93.
Two indirect arterial pressure monitors, the Finapres and theAccutorr, were investigated and compared with the direct measurementof intra-arterial pressure. Pressures in patients in a varietyof circulatory states were measured and analysed in relationto two types of random error: first, the "intra-individual standarderror" (within one session of measurement) and second, the "inter-individualstandard error" (between sessions). (This distinction is important,since in routine monitoring of arterial pressure one is usuallydealing with the first type of error only.) This study showedthat sudden changes in pressure were closely followed by theFinapres. A pressure reading of the Accutorr takes about 1520s, meaning that, within this period, variations will not beobserved. The accuracy or reproducibility of each method, asexpressed in intra-individual variance, diminished in the orderIntra-Arterial-Line, Finapres, Accutorr. The inter-individualvariation decreased in the order Intra-Arterial-Line, Accutorr,Finapres. Most of the inter-individual variance of the Finapresis probably real because of the more peripheral position ofits cuff. A correlation between malfunctioning of the Finapresand vasoconstriction or hypothermia of the finger could notbe demonstrated. 相似文献
94.
GEUKENS R.; VAN DE WERF F.; ECTOR H.; STALPAERT G.; DE GEEST H. 《European heart journal》1987,8(4):431-434
A Caucasian female patient with repetitive attacks of ventriculartachycardia and fibrillation caused by annular submitral leftventricular aneurysm is reported. During a follow-up periodof six years after aneurysmectomy, the patient remained symptom-free. 相似文献
95.
96.
Efficacy of recombinant granulocyte colony-stimulating factor (rhG-CSF) in experimental colitis 总被引:1,自引:0,他引:1 下载免费PDF全文
D W HOMMES J MEENAN S DIJKHUIZEN F J W TEN KATE G N J TYTGAT S J H VAN DEVENTER 《Clinical and experimental immunology》1996,106(3):529-533
Inflammatory bowel disease is associated with mucosal neutrophil recruitment and activatation, mediated in part by arachidonic acid metabolites. G-CSF attenuates the immune response to sepsis and ameliorates glycogen storage disease Ib-related colitis. These actions may be effected through the shedding of neutrophil adhesion molecules, or inhibition of proinflammatory mediator synthesis. Immune complex colitis was used to evaluate the effect of rhG-CSF on colonic mucosal inflammation, neutrophil recruitment and the generation of eicosanoids. Immune complex colitis was induced in White New Zealand rabbits. Animals were pretreated with rhG-CSF either 24 h before induction, or at induction, with dosages of 50 and 200 μg/kg. rhG-CSF caused a time- and dose-dependent neutrophilia in all animals. Pretreatment with rhG-CSF resulted in increased tissue myeloperoxidase levels, despite a histologically similar mucosal polymorphonuclear cell infiltrate between treated and control colitis groups. Leukotriene B4 (LTB4) and thromboxane B2 (TXB2) dialysis fluid levels were lower in treated animals, in particular in the groups receiving two doses (LTB4: both P < 0.01; TXB2: both P < 0.01. Prostaglandin E2 (PGE2) levels in dialysis fluid of the rhG-CSF-treated animals showed no difference from controls. In this model of experimental colitis, high-dose therapy with G-CSF resulted in a marked decrease of proinflammatory mediators, but mucosal generation of the protective PGE2 was preserved. These results suggest that prolonged high-dose therapy with G-CSF may have anti-inflammatory effects in colitis. 相似文献
97.
E. VAN LOGHEM B. FRANGIONE B. RECHT E. C. FRANKLIN 《Scandinavian journal of immunology》1982,15(3):275-278
Staphylocoecal protein A binds molecules belonging to the IgGl, IgG2, and IgG4 sub-classes. IgG3 proteins generally do not bind, except for those coded by the two γ3 alleles, which are G3m(u− ): G3m(b0 ,b3 ,b5 ,s,v) and G3m(b0 ,b3 ,b5 ,s,t,v). G3m(u) is located in the CH 2 domain. The difference between G3m(u− ) and G3m(u+ ) IgG3 proteins correlates with the sequence at position 339 in the CH 2 domain—Ala and Thr respectively. There is another structural difference in the CH3 domain which correlates with protein A binding and non-binding: all IgG proteins that bind protein A have His at position 435, whereas those that do not, have Arg at that position. 相似文献
98.
JORENS PH. G.; VAN DEN HEUVEL P. A.; CUYKENS J.-J.; VAN CAUWELAERT P. A.; PARIZEL G. A.; MERTENS A. N. 《European heart journal》1990,11(5):476-478
This article describes a case of infective aortic valve endocarditisdue to Fusarium oxysporum occurring 4 years after coronary arterybypass grafting. It is the first reported case of endocarditiscaused by Fusarium. 相似文献
99.
REENDERS K; DE NOBEL E; HOOGEN HJM VAN DEN; RUTTEN GEHM; VAN WEEL C 《Family practice》1993,10(2):169-172
The aim of this study was to assess the prevalence of long-termcomplications in all patients with non-insulin-dependent diabetesmellitus, who were known to their general practitioners (GPs).During one year 19 GPs in the area of Hoogeveen in the Netherlandsexamined their non-insulin-dependent (NIDDM) patients, includingthose under specialist's care. A detailed protocol was used;the GPs were trained in the diagnostic procedures. Complicationswere either already known from the records or newly discoveredduring screening. In a population of 41940 14.5/1000 patientswith diabetes were identified: 12/1000 NIDDM and 2.5/1000 insulin-dependent-diabetesmellitus (IDDM). Of the 509 NIDDM patients, 387 (76%) couldbe screened for late complications. Signs and symptoms of latecomplications were found in many patients: retinopathy (14%),nephropathy (57%), neuropathy (68%) and macroangiopathy (53%).The prevalence of serious complications was: proliferative retino-and maculopathy (3.3%); diabetic foot (2.6%); renal failure(2.5%). The systemic screening revealed a high number of previouslyunknown cases. It is concluded that many patients with NIDDMdevelop signs and symptoms of late complications. Most casesare identified by systemic screening only. More long-term studiesof the prognosis of late com plications in NIDDM are needed. 相似文献
100.
VAN DER SPEK A. F. L.; REYNOLDS P. I.; FANG W. B.; ASHTON-MILLER J. A.; STOHLER C. S.; SCHORK M. A. 《British journal of anaesthesia》1990,64(1):21-27
Mouth opening was measured in 43 children anaesthetized withisoflurane and paralysed with vecuronium or suxamethonium. Measurementsof mouth opening were made for up to 10 min after loss of theadductor pollicis twitch and cessation of muscle fasciculations.In 22 patients receiving suxamethonium, a significant (P <0.001) reduction in mean mouth opening occurred in the 60 safter loss of twitch and cessation of fasciculations. Mouthopening reductions could last for up to 10 min after the lossof twitch, beyond the return of the twitch. One patient experienced"masseter spasm"; he did not develop malignant hyperpyrexiaduring 2.5 h of isoflurane anaesthesia. Patients receiving vecuroniumshowed a significant (P < 0.0006) increase in mouth opening.In 20 subjects, mouth opening was generated with a small (1.67N) and a larger (4.32 N) force. Proportionally equal reductionsin mouth opening were obtained with either force after suxamethoniumadministration. Relatively equal increases with either forcefollowed vecuronium administration. Isolated masseter spasmis not pathognomonic for malignant hyperpyrexia. If the diagnosisof malignant hyperpyrexia is contemplated, signs of hypermetabolism,such as increases in end-tidal carbon dioxide concentrationduring constant minute ventilation, should be sought. 相似文献