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31.

Objective

Outdoor free play is important for preschoolers' physical activity, health, and development. Certain temperamental characteristics are associated with obesity, nutrition, and sedentary behaviors in preschoolers, but the relationship between temperament and outdoor play has not been examined. This study examined whether there is an association between temperament and outdoor play in young children.

Methods

Healthy children aged 1 to 5 years recruited to The Applied Research Group for Kids (TARGet Kids!), a community-based primary care research network, from July 2008 to September 2013 were included. Parent-reported child temperament was assessed using the Childhood Behavior Questionnaire. Outdoor free play and other potential confounding variables were assessed through validated questionnaires. Multivariable linear regression was used to determine the association between temperament and outdoor play, adjusted for potential confounders.

Results

There were 3393 children with data on outdoor play. The association between negative affectivity and outdoor play was moderated by sex; in boys, for every 1-point increase in negative affectivity score, mean outdoor play decreased by 4.7 minutes per day. There was no significant association in girls. Surgency was associated with outdoor play; for every 1-point increase in surgency/extraversion, outdoor play increased by 4.6 minutes per day.

Conclusions

Young children's temperamental characteristics were associated with their participation in outdoor free play. Consideration of temperament could enhance interventions and strategies to increase outdoor play in young children. Longitudinal studies are needed to elucidate the relationship between children's early temperament and physical activity.  相似文献   
32.
A calcium-binding immunoglobulin G (IgGIRUP) was identified in the serum of a patient with multiple myeloma, asymptomatic hypercalcemia, and a normal ionized serum calcium. Calcium binding by IgGRUP was confirmed by two-dimensional electrophoresis with calcium-45 and equilibrium dialysis. Amino acid analyses indicated an unusually high number of glutamic (or glutamine) residues in the L chain and Fab fragment but no detectable -carboxyglutamic acid. As determined by equilibrium dialysis with45Ca, the intact IgGRUP and its Fab fragments bound calcium at an optimum pH of 7.4. There was minimal binding of calcium to H chains and no binding by L chains or the Fc fragment. Recombination of H and L chains partially restored the binding activity. By Scatchard analysis, the binding affinity (K d) of IgGRUP was 1.7×10–3 M and the binding capacity was 4 mol of calcium/mol of IgG. The binding of 4 mol of calcium/mol of IgG is twice that reported previously for two other calcium-binding myeloma proteins and suggests unique properties of IgGRUP.  相似文献   
33.
To assess the in vivo steroidogenic activity of desialylated human choriogonadotropin (hCG) in man, highly purified desialylated hCG was administered as a constant intravenous infusion over 6 hours to four normal men at a rate sufficient to maintain substantial levels of desialylated hCG in the serum. The mean percent change of serum testosterone from baseline during the first 6 hours in men given an infusion of desialylated hCG was compared to that in saline-infused controls and that in men given highly purified intact hCG. The mean change of serum testosterone at 6 hours in the group infused with desialylated hCG (129% of baseline) was significantly greater than that of the controls (69% of baseline). Furthermore, the response to desialylated hCG could not be distinguished from that of hCG (125% of baseline). It was concluded that desialylated hCG, when given as a constant intravenous infusion, can elicit a substantial serum testosterone response comparable to that seen with purified hCG, and thus, that desialylated hCG behaves as an agonist of the LH/CG receptors on human Leydig cells.  相似文献   
34.
Previous investigations of patients with gestational trophoblastic neoplasia have shown that their urines often contain carboxyterminal peptide (CTP) fragments of the choriogonadotropin (hCG) beta-subunit as well as forms of hCG deficient in sialic acid. In order to determine whether beta-CTP fragments are among the urinary products of the peripheral degradation of desialylated hCG (as-hCG), using a continuous infusion technique, we gave highly purified as-hCG to humans. Six healthy subjects were given a loading dose of 0.8 mg of as-hCG followed by an infusion of the same preparation. An overall mean infusion rate of 62.9 micrograms/min was maintained for 6 h, and the mean serum concentration of as-hCG achieved during the infusion was 72.1 ng/ml. In all six subjects, beta-CTP fragments were the predominant immunoreactive forms of as-hCG in urine obtained during the infusion. In contrast, the urine of subjects infused with hCG has been shown to contain hCG itself, but nil beta-CTP fragments or as-hCG. After the as-hCG infusion was stopped, the excretion of the beta-CTP fragments in urine declined rapidly. There were no beta-CTP fragments detectable in sera obtained during the infusion or in sera incubated with as-hCG at 37 degrees C. After incubation with as-hCG for 4 h, the urine of normal subjects contained small amounts of beta-CTP fragments; however, the apparent proteolytic activity was too low to account for either the quantity of beta-CTP fragments produced during the infusion or the extremely low levels of as-hCG in the urine. These data demonstrate the existence in humans of a peripheral metabolic pathway that cleaves beta-CTP fragments from as-hCG and allows their excretion in urine. Thus, the frequent presence of beta-CTP fragments in the urines of patients with gestational trophoblastic neoplasia can be accounted for in part by the metabolism of the forms of hCG that bear an altered carbohydrate structure, which are prevalent in this disease.  相似文献   
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38.
Peptide variations in the alpha-subunit (molecules starting at alpha 3 and alpha 4) and beta-subunit (missing linkages at beta 44-45 and beta 47-48) of hCG have been reported by several investigators. Studies, however, have been limited to standard hCG preparations (purified from large pools of urine) and other hCG samples from mixed urines. In this study we used chromatographic procedures to purify the total hCG content of 13 individual urines, 6 from patients with pregnancy and 7 from those with trophoblast disease (no hCG-containing fractions were excluded). Then, we examined for the first time the peptide variability among individual samples of hCG. We report 1) that individual hCG preparations have nicks (missing linkages) in the beta-subunit, primarily between residue 47-48 (11 of 13 samples) and, less commonly, at the linkage 44-45 or 46-47 (3 of 13 samples); 2) the extent of nicking varies greatly between individual preparations (range, 0-100% of molecules); 3) varying alpha-subunit N-terminal heterogeneity (N-terminus starting at alpha 3 or alpha 4) was also present (range, 0-28% of molecules), but was confined to preparations from individuals with trophoblast disease (6 of 7 samples from trophoblast disease urine, 0 of 6 from pregnancy urine); 4) hCG missing the beta-subunit C-terminal region was also detected (2 of 13 hCG preparations); and 5) 1 of 13 preparations was nicked on the hCG alpha-subunit, between residues 70 and 71. Thus, 12 of 13 individual hCG samples demonstrated at least 1 of 4 different forms of peptide heterogeneity. We conclude that individual hCG samples vary widely in the type and extent of peptide heterogeneity, an observation that is not appreciated when pools of hCG are studied.  相似文献   
39.
The gonadotropins are a family of closely related heterodimeric glycoprotein hormones homologous in structure to disulfide-knot growth factors. Metabolic proteolytic processing in vivo of this disulfide cross-linked region results in urinary excretion of a residual highly stable core structure. The primary structure of the pituitary form of the hLH beta core was reported earlier, but it has proved difficult to isolate the urinary core, although antibodies to the pituitary core demonstrated its presence. By conventional and immunoaffinity methods, the urinary core has been isolated and its structure determined by both chemical and mass spectrometric methods. The urinary hLH beta core is the same as the pituitary-extracted hLH beta core, beta 6-40 disulfide bridged to beta 55-93, except that the pituitary core is more heterogeneous containing also beta 49-93. These findings imply a dual origin of urinary cores, both directly from a secreting tissue and by kidney processing of circulating hormone. We also found that pregnant chimpanzees excrete a CG beta core with a primary structure identical to that of the human CG beta core of pregnancy. In conclusion, gonadotropin core generation and urinary excretion of nearly identical gonadotropin metabolites is common among primates. Although possible biological functions of these core fragments remain unproven, they have diagnostic utility because of their stability and abundance.  相似文献   
40.
Acute left main coronary artery (LMCA) occlusion is associated with a high mortality rate. The majority of patients with this clinical condition die suddenly or from cardiogenic shock. We report a case of cardiogenic shock resulting from acute main coronary occlusion. Emergency cardiac catheterization was performed and coronary angiography showed a totally occluded LMCA. Prompt revascularization by means of primary LMCA stenting was successful and the patient was discharged 16 days later without neurological deficit or clinical signs of heart failure. We suggest that the rapid coronary angiography followed by angioplasty and primary stent implantation was instrumental in saving this patient's life.  相似文献   
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