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161.
162.
An imprint immunofixation (IIF) technique for the characterization of electrofocused immunoglobulins (Ig) is described. Electrofocused proteins are blotted (imprinted) from the separating polyacrylamide gel to agarose gels by gel-to-gel overlays. The protein imprints are chemically fixed in the agarose gels with a solution of 46% methanol, 8% acetic acid and 46% water. The imprinted Ig are then identified radioimmunologically, using an indirect system with monoclonal mouse anti-human Ig antibodies in the first layer and 125I-labelled rabbit anti-mouse Ig in the second, followed by autoradiography. The method is sensitive and permits characterization of Ig in unconcentrated cerebrospinal fluid. By sequential imprinting, each separated specimen can be characterized for up to 10 separate antigenic determinants without loss of sensitivity.  相似文献   
163.
PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200.  相似文献   
164.
Experiments were conducted to establish whether diminished solute reabsorption in the loop of Henle during acute renal failure could explain the loss of urinary concentration and participate in generating a tubuloglomerular feedback-mediated reduction in filtration rate. The electrolyte content of the fluid in the ascending limb of the loop of Henle was determined in situ by monitoring its electrical conductivity after propulsion into the distal tubule with a sudden burst perfusion. The value of the minimum electrolyte concentration decreased exponentially with increasing equilibration time, reaching a steady-state value equivalent to 27±9 mM NaCl in normal kidneys, 34±15 mM in mercuric chloride kidneys and 53±22 mM following ischaemia. A mathematical model was derived to describe the process of sodium chloride dilution from which it was possible to calculate both the permeability and transport velocity of the cortical thick ascending limb. In the normal kidney, the transport velocity was calculated to be 4.65±0.92 ·10–5 cm/s, a value not significantly different from that of the mercuric chloride or ischaemic kidneys, and the estimated permeability was 1.13±0.52·10–5 cm/s, not different from that of the mercuric chloride kidneys but significantly lower than that calculated for the ischaemic kidneys. It is concluded that for the more severely damaged ischaemic model, the loss of urinary concentrating ability was accompanied by a reduction in diluting ability of the ascending limb of the short loop of Henle, which appears to be due, at least in part, to an elevation of the passive permeability to sodium chloride in this segment.  相似文献   
165.
Summary Hybridoma cell lines grown as ascites tumors in pristane primed mice will frequently yield milligram quantities of monoclonal antibody per milliliter of ascites fluid. Ascites production is an excellent method for the research scientist to generate high titer antibody with minimal effort. Through commercial production, gram to kilogram quantities can be achieved.  相似文献   
166.
We are elaborating on the kinetics and mechanisms of septic rabbit liver to de novo biosynthesize acute-phase response (APR) proteins under in vitro conditions of deepening ischemia in reference to their in vivo prevalence in serum and cerebrospinal fluids (CSF) collected at predetermined times. The significance of the data is interpreted as relevant to grafting cadaveric liver into end-stage liver diseased patients and APR-induced ischemic heart diseases (IHD). Hepatic APR was induced by CCl(4)-intubation, and the administration of cholera toxin (CT) or scorpion venom (SV), or both, to rabbits. Hepatic functional efficiency, in terms of biosynthesis of APR proteins in closed circuit perfusion of the isolated intoxicated liver with oxygenated saline or L-15 media paralleled the two-dimensional immunoelectrophoresis (2D-IEP) spectrum of APR serum proteins at time of liver isolation. We are suggesting: (a) in vitro biosynthesis of plasma proteins by isolated perfused liver is the result of in vivo decoded and retained APR inflammatory signals; and (b) decoded inflammatory signals are expressed not withstanding the perfusate's organic composition. Furthermore, 90 min of ischemic perfusion in saline or L-15 medium precipitated mitochondrial aberrations which resulted in further deterioration of de novo biosynthesis of APR plasma proteins. Regardless of the nature of the inflammatory stimuli, mitochondrial aberrations rendered the perfused organ a biologically inert tissue mass that was incapable of resuming biological function upon perfusion with oxygenated L-15 medium. This is most likely due to ischemia-induced irreversible hepatic necrosis. Thus, in vitro aberrations of mitochondrial function(s) critically limit the capability of the isolated liver to resume its organic function to sustain biosynthesis of de novo plasma proteins. Extrapolation of these results to the surgical management of end-stage liver diseases points to the importance of the status and the handling protocol(s) of the cadaver donor liver prior to successful grafting. We conclude that although histology of a cadaver liver may reveal well-preserved hepatic cellular organelles with at least minimal intra- and intercellular communication required for viable hepatic function, we deem it essential to further define acceptable minimal capabilities to de novo biosynthesize plasma proteins by a cadaver liver as a measure of its functional viability and suitability for transplantation. Ultimately, this measure may improve the success of liver transplants with minimal surgical and drug interventions.  相似文献   
167.
类风湿性关节炎患者关节滑膜液浸润的T细胞表达特性   总被引:8,自引:0,他引:8  
目的 :为研究类风湿性关节炎 (RA)患者关节滑膜液浸润的淋巴细胞介导自身免疫病的特性 ,分析了 2 2例RA患者滑膜液中淋巴细胞的免疫表型、对II型胶原的反应频率及IL 10、IL 12的分泌格局。方法 :用流式细胞术分别测定滑膜液和外周血淋巴细胞表型 ,并采用国际标准半有限稀释法分析了关节滑膜液中浸润的淋巴细胞对II型胶原 (CII)的反应频率 ,同时用ELISA方法检测了滑膜液与外周血中IL 10与IL 12含量。结果 :滑膜液中的T淋巴细胞的表型分别为CD4 (39 6 %±10 5 % )和CD8细胞 (36 4 %± 16 4 % ) ,CD4 CD8细胞比值显著低于外周血 ,且同时表达CD16和CD5 6的活化NK细胞占15 5 %± 11 1%。T细胞受体谱取用表明仍以αβTCR为主 (6 9 6 %± 15 7% )。有意义的是 :滑膜液中的T细胞对CII的反应频率为 15 2× 10 - 6 ,远远高于外周血 (4 0× 10 - 6 )。IL 12含量为 (4 19 9± 89 2 )pg ml,IL 10含量为 (187 7± 34 5 )pg ml,与外周血中这 2种细胞因子的含量〔分别为IL 12 :(6 5 32± 34 2 )pg ml和IL 10 :(85± 12 7)pg ml〕比较 ,具有显著的统计学差异。结论 :上述实验结果表明这种具有表达特性的浸润T细胞介导了RA患者关节滑膜组织的免疫损伤。  相似文献   
168.
分泌性中耳炎中耳积液和血清中sIL-2R水平的初步研究   总被引:2,自引:0,他引:2  
应用酶联免疫吸附法(ELISA)对30例正常人血清(对照组)和60例分泌性中耳炎患者(SOM组)中耳积液和血清中可溶性白细胞介素2受体(sIL-2R)进行了检测。结果示SOM组血清sIL-2R水平明显高于对照组,MEF中其含量明显高于血清;鼻咽癌组血清及MEF中sIL-2R水平明显高于─般SOM组;粘液组高浆液组;慢性组高于急性组(均P<0.01)。提示:血清及MEF中sIL-2R水平的测定有助于对SOM患者免疫状态的评估;MEF中sIL-2R可能主要由局部中耳粘膜产生;MEP中高浓度的sIL-2R存在可能是SOM迁延不愈的─个原因。  相似文献   
169.
By two-colour flow cytometric analysis, we found increased numbers of B cells co-expressing the pan-T cell marker CD5 and the B cell marker CD19 in cerebrospinal fluid (CSF) of 21 patients with multiple sclerosis (MS), compared with 17 control subjects with muscular tension headache. Only one patient with MS, but nine controls lacked CD5+ B cells in CSF. This difference was not observed in peripheral blood. Numbers of CD5+19+ B cells were increased in CSF compared with blood in MS, but not in the controls. In both groups, CD5+19+ B cells were not restricted to small resting lymphocytes, but were also found among larger-sized lymphocytes. The relative density of CD5 molecules and of CD19 molecules was lower in CD5+19+ than in CD5-19+ B cells and CD5+19- T cells. CD5+ B cells are assumed to be responsible for autoantibody production, and our results suggest a pathogenetic role of such cells, predominantly within the central nervous system, in MS.  相似文献   
170.
The last decade has witnessed increasing application of human cytogenetic technology to prenatal chromosome analysis. However, unlike the rather uniform peripheral blood T-lymphocyte system which has provided most of our experience in human cytogenetics, long-term amniotic-fluid cell cultures display extreme cellular heterogeneity and disproportionate growth of certain cell types as a consequence of clonal amplification. When they enter cell culture, many of these cells are approching the terminal stages of their respective life spans and may have accumulated chromosomal aberrations. Concern about the possibility of true fetal mosaicism seems warranted chiefly in situations were multiple colonies display potentially viable aberrations. Clonal analysis, preferable of multiple clonal types, and attention to details of clonal morphology are likely to minimize diagnostic errors and undue apprehension resulting from mosaicism in amniotic-fluid cell cultures.  相似文献   
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