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101.
R J Merritt M Carter M Haight L D Eisenberg 《Journal of pediatric gastroenterology and nutrition》1990,11(1):78-82
Twenty-one infants less than 6 months of age with gastrointestinal symptoms of cow milk and/or soy protein-based infant formula intolerance (diarrhea in 14, hematochezia in 16, emesis in 8, failure to thrive in 4, and colic in 10) were treated clinically with a whey protein hydrolysate formula. Six patients improved when placed directly on the formula, and 15 remained asymptomatic or improved when given the whey hydrolysate formula following initial treatment with a casein hydrolysate or elemental formula. Eighteen had supporting evidence of an allergic basis for their symptoms, including a family history of allergies in 6, a clinical challenge with the offending formula in 1, laboratory tests consistent with atopy in 11, and/or rectal biopsy with histologic allergic features in 7. The whey hydrolysate formula may be an acceptable alternative to soy or casein hydrolysate formulas in most infants with gastrointestinal symptoms of cow milk and/or formula intolerance. 相似文献
102.
103.
J B Schwartz M H Cheng A D Ramos R J Merritt A C Platzker 《Journal of perinatology》1990,10(4):376-379
Plasma ammonia concentration in neonates has routinely been determined using arterial or venous blood. Expected plasma ammonia values in capillary blood obtained by heelstick have not been determined. We compared ammonia levels in 20 sets of plasma from simultaneously drawn arterial, venous, and capillary blood in a group of neonates receiving total parenteral nutrition. Mean ammonia concentrations in venous (107 +/- 44) and capillary blood (112 +/- 33) were 45% and 51% higher, respectively, than corresponding arterial (74 +/- 22) values (P less than .001). Ammonia levels in blood obtained by venipuncture (Ven), however, did not correlate consistently with arterial (Art) values (r = .43; Art = 51 + 0.21 Ven; P greater than .05). In contrast, ammonia levels in capillary blood (Cap) correlated well with arterial values (r = .86; Art = 10.3 + 0.6Cap; P less than .001). Ammonia levels in neonates may be reliably interpreted using the latter regression equation when blood for analysis is obtained by a properly performed heelstick, allowing the preservation of arteries and veins, and sparing the infant from repetitive needle punctures. Ammonia levels in blood obtained by venipuncture do not adequately correlate with arterial values and therefore may be therapeutically misleading. 相似文献
104.
G. David Gentry Cindy J. Merritt Lawrence D. Middaugh 《Neurotoxicology and teratology》1995,17(6):673-677
This study was designed to further explore the nature of our previously reported reduction in the efficacy of food reinforcers for prenatal ethanol-exposed mice. We determined the effect of prenatal ethanol exposure on responding for food delivered on a progressive-ratio (PR) reinforcement schedule, which has been shown to be sensitive to changes in motivation and/or value of reinforcers, and we assessed the effects of amphetamine on responding maintained by the PR schedule. Subjects were adult (12 months old) male offspring of C57BL/6J mice fed liquid diets containing either ethanol (25% ethanol-derived calories, N = 12) or sucrose (25% sucrose-derived calories, N = 9) during gestation days 5–17. Prenatal ethanol-exposed mice differed from controls by having lower response rates and a greater disruption of responding following amphetamine injections. The reduced responding for food reward on the PR schedule supports our previously advanced hypothesis that prenatal ethanol reduces the efficacy of food reinforcers. The enhanced effects of amphetamine found in these adult mice is in agreement with previous reports on young rats. Although either of the effects of prenatal ethanol exposure observed in the present study are suggestive of altered DA systems, current neurochemical studies on either rats or mice provide no support for the hypothesis. 相似文献
105.
The glycosphingolipids GD3, GM3, and alpha 2, 3-sialosylparagloboside (SPG) are major gangliosides of lymphoid leukemia cells. The reactivity of two monoclonal anti-ganglioside antibodies, an anti-GD3 (R24) and an antibody cross-reactive to GM3 and SPG (M2590), to blasts of patients with T-cell acute lymphoblastic leukemia (ALL) and B-cell precursor ALL (pre-B-ALL), were compared using indirect immunofluorescence and flow cytometry. Results from 23 patients with T-ALL and eight with pre-B-ALL yielded four subclasses of T-ALL and two subclasses of pre-B-ALL. Blasts from most of the patients with T-ALL were R24+M2590- whereas most of the patients with pre-B-ALL were R24-M2590-. Seven of 23 patients with T-ALL had ganglioside immunophenotypes similar to that of pre-B-ALL, i.e. R24-M2590- or R24-M2590+. These subclasses could not be further characterized by additional cell surface immunophenotypic markers or by gene (immunoglobulin and T-cell receptor) rearrangement analysis. The ratio R24/M2590 was less than 1.0 in all patients with pre-B-ALL, and was greater than 1.0 in all patients with T-ALL who were R24 positive, but was not useful in characterizing the double negative T-ALL subclass. To assess whether cryptogenicity of gangliosides due to cell surface protein could account for the low binding of either R24 or M2590, blasts were treated with trypsin before antibody analysis. Whereas the binding of R24 was unchanged after trypsin treatment, binding of M2590 was increased in a number of samples, particularly in those samples which were originally M2590-positive. The results show that comparative staining of T-ALL and pre-B-ALL cells with both anti-GD3 and anti-GM3/SPG antibodies results in a further subclassification of ALL and provides a quantitative assessment of the expression of tumor-associated gangliosides on the blasts of this disease. 相似文献
106.
The severity and persistence of corticosteroid-induced obesity were evaluated retrospectively in 23 children aged 1-14 yrs requiring more than 60 days of therapy with prednisone for idiopathic nephrotic syndrome. Mean relative weight (after clearing of proteinuria) at initiation of therapy was 107 +/- 10 percent. Peak relative weight on therapy was 119 +/- 15 percent following a mean total of 31 months of cumulative steroid therapy. The most recent available relative weight in remission at least 6 months following cessation of therapy was 107 +/- 18 percent. The number of children whose relative weight exceeded 120 percent at initiation of, during and following therapy was 3, 10, and 4, respectively. In those with normal initial relative weight (less than 110%) there was no persistent obesity. Two of three initially obese patients (relative weight greater than 120%) remained obese. All patients with persistent obesity following therapy had initial relative weight of at least 110 percent and peak relative weight of more than 130 percent. The risk of persistent obesity as a result of chronic corticosteroid therapy in initially normal weight children who do not exceed 130 percent relative weight during therapy appears to be small. 相似文献
107.
We describe an 18-month intervention that was designed to improve opportunistic screening for chlamydia in General Practice. Key strategies included engaging and informing general practitioners, adopting a simplified screening protocol, providing feedback on practice testing performance and developing resources for use with patients. This uncontrolled before and after study found that the overall impact on testing was modest and largely transient, and was insufficient to impact on the current chlamydia epidemic. Major additional measures would be required to further substantially increase testing levels. These could include financial incentives linked to screening performance and increased community awareness to increase patient demand for testing. 相似文献
108.
109.
Influence of amino acid administration on whole-body leucine kinetics and resting metabolic rate in postabsorptive normal subjects 总被引:1,自引:0,他引:1
P J Pacy J S Garrow G C Ford H Merritt D Halliday 《Clinical science (London, England : 1979)》1988,75(3):225-231
1. We have investigated the effect of an amino acid mixture (Vamin 14; 57.4 +/- 10.2 mumol h-1 kg-1) on whole-body leucine kinetics, calculated by a steady-state reciprocal pool model, and resting metabolic rate in eight postabsorptive normal subjects. 2. Vamin 14 infusion increased whole-body leucine flux (P less than 0.001), leucine employed for protein synthesis (P less than 0.001), leucine oxidation (P less than 0.001), metabolic clearance rate of alpha-ketoisocaproic acid (P less than 0.05) and levels of all three branched-chain amino acids (P less than 0.001) compared with the basal situation. In contrast, whole-body proteolysis was reduced (P less than 0.05). 3. Resting metabolic rate was increased during Vamin 14 infusion (P less than 0.05) and was positively correlated with whole-body protein synthesis (n = 16, r = 0.6342, P less than 0.01; y = 0.605x + 173.7), as was the change in metabolic rate with the change in protein synthesis (n = 8, r = 0.772, P less than 0.05; y = 0.493x - 10.85). 4. Overall, Vamin 14 infusion was associated with increased blood glucose (P less than 0.001), although the observed increase in plasma glucagon (t = 2.012) and plasma insulin (t = 1.683) failed to reach statistical significance. 5. These data lend a measure of support to the hypothesis that the apparent increase in whole-body protein synthesis in insulin-dependent diabetic (type I) subjects during insulin withdrawal may be substrate related. 相似文献
110.
DNA binding to human leukocytes. Evidence for a receptor-mediated association, internalization, and degradation of DNA. 总被引:19,自引:5,他引:19 下载免费PDF全文
Previous studies have indicated that white blood cells possess DNA on their outer membranes. In this study we set out to determine whether exogenous DNA bound to cells in a fashion compatible with a ligand receptor union. Purified populations of white blood cells; neutrophils (polymorphonuclear leukocytes, PMN), adherent mononuclear cells (ADMC), rosetting lymphocytes (E+ cells), and nonrosetting lymphocytes (E- cells) were incubated with radiolabeled lambda phage DNA in increasing concentrations. Binding of [3H]DNA was a saturable process and was inhibited by excess cold DNA and prior trypsinization of the cells. Rate zonal density centrifugation of purified cell membrane preparations confirmed that DNA was binding to the outer cell surface. The dissociation constant for all four cell types was approximately 10(-9) M, and from 0.81 X 10(3) to 2.6 X 10(3) molecules of lambda phage DNA bound to each cell depending upon cell type. Binding was not competitively inhibited by RNA, polydeoxyadenylic acid-polydeoxythymidylic acid (poly [d(A).d(T)]), or mononucleotides. Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE)-separated proteins from PMN, ADMC, E+, and E- cells were electrophoretically blotted onto nitrocellulose sheets; a probe of biotin-labeled DNA indicated a single species of DNA-binding molecule migrating in a position consistent with a molecular weight of 30,000. Isotopic and immunofluorescent studies indicate that DNA is internalized and degraded to oligonucleotides; this process is inhibited by cycloheximide. These results support the notion that there is a common binding site for DNA on white blood cells, that the stoichiometry of the association is compatible with a ligand receptor relationship, and that this apparent receptor is responsible for the endocytosis and degradation of exogenous DNA. 相似文献