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31.
Activated p38gamma MAP kinase exhibited significant basal ATPase activity in the absence of a kinase substrate, and addition of a phosphoacceptor substrate increased k(cat)/K(m)20-fold. AMP-PCP was competitive with ATP binding and non-competitive with phosphoacceptor substrate binding. The nucleotide binding site affinity label 5'-(p-fluorosulfonylbenzoyl)adenosine (FSBA) bound stoichiometrically at Lys-56 in the ATP site of both unphosphorylated and activated p38gamma. AMP-PCP only protected the activated enzyme from FSBA inactivation, implying that AMP-PCP does not bind unphosphorylated p38gamma. Basal ATPase activities were also observed for activated p38alpha, ERK2 and JNK3 suggesting that the enzymatic mechanism may be similar for all classes of MAP kinases.  相似文献   
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Smoke inhalation injuries are the leading cause of mortality from burn injury. Airway obstruction due to mucus plugging and bronchoconstriction can cause severe ventilation inhomogeneity and worsen hypoxia. Studies describing changes of viscoelastic characteristics of the lung after smoke inhalation are missing. We present results of a new smoke inhalation device in sheep and describe pathophysiological changes after smoke exposure. Fifteen female Merino ewes were anesthetized and intubated. Baseline data using electrical impedance tomography and multiple-breath inert-gas washout were obtained by measuring ventilation distribution, functional residual capacity, lung clearance index, dynamic compliance, and stress index. Ten sheep were exposed to standardized cotton smoke insufflations and five sheep to sham smoke insufflations. Measured carboxyhemoglobin before inhalation was 3.87 +/- 0.28% and 5 min after smoke was 61.5 +/- 2.1%, range 50-69.4% (P < 0.001). Two hours after smoke functional residual capacity decreased from 1,773 +/- 226 to 1,006 +/- 129 ml and lung clearance index increased from 10.4 +/- 0.4 to 14.2 +/- 0.9. Dynamic compliance decreased from 56.6 +/- 5.5 to 32.8 +/- 3.2 ml/cmH(2)O. Stress index increased from 0.994 +/- 0.009 to 1.081 +/- 0.011 (P < 0.01) (all means +/- SE, P < 0.05). Electrical impedance tomography showed a shift of ventilation from the dependent to the independent lung after smoke exposure. No significant change was seen in the sham group. Smoke inhalation caused immediate onset in pulmonary dysfunction and significant ventilation inhomogeneity. The smoke inhalation device as presented may be useful for interventional studies.  相似文献   
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We derive a reaction–diffusion system modeling the spatial propagation of a disease with kinetics occurring on distinct spatial domains. This corresponds to the actual invasion of a disease from a species living in a given spatial domain toward a second species living in a different spatial domain. We study the global existence of solutions and discuss the long time behavior of solutions. Then we consider a special case, based on a model of brain worm infection from white-tailed deer to moose populations, for which we discuss the invasion success/failure process and disprove a conjecture stated in an earlier work.  相似文献   
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The preschool years offer an opportunity to interrupt the trajectory toward obesity in black children. The Hip-Hop to Health Jr. Obesity Prevention Effectiveness Trial was a group-randomized controlled trial assessing the feasibility and effectiveness of a teacher-delivered weight control intervention for black preschool children. The 618 participating children were enrolled in 18 schools administered by the Chicago Public Schools. Children enrolled in the nine schools randomized to the intervention group received a 14-week weight control intervention delivered by their classroom teachers. Children in the nine control schools received a general health intervention. Height and weight, physical activity, screen time, and diet data were collected at baseline and postintervention. At postintervention, children in the intervention schools engaged in more moderate-to-vigorous physical activity (MVPA) than children in the control schools (difference between adjusted group means = 7.46 min/day, P = 0.02). Also, children in the intervention group had less total screen time (-27.8 min/day, P = 0.05). There were no significant differences in BMI, BMI Z score, or dietary intake. It is feasible to adapt an obesity prevention program to be taught by classroom teachers. The intervention showed positive influences on physical activity and screen time, but not on diet. Measuring diet and physical activity in preschool children remains a challenge, and interventions delivered by classroom teachers require both intensive initial training and ongoing individualized supervision.  相似文献   
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Objective:

This pilot study tested the feasibility of Family‐Based Hip‐Hop to Health, a school‐based obesity prevention intervention for 3–5‐year‐old Latino children and their parents, and estimated its effectiveness in producing smaller average changes in BMI at 1‐year follow‐up.

Design and Methods:

Four Head Start preschools administered through the Chicago Public Schools were randomly assigned to receive a Family‐Based Intervention (FBI) or a General Health Intervention (GHI).

Results:

Parents signed consent forms for 147 of the 157 children enrolled. Both the school‐based and family‐based components of the intervention were feasible, but attendance for the parent intervention sessions was low. Contrary to expectations, a downtrend in BMI Z‐score was observed in both the intervention and control groups.

Conclusions:

While the data reflect a downward trend in obesity among these young Hispanic children, obesity rates remained higher at 1‐year follow‐up (15%) than those reported by the National Health and Nutrition Examination Survey (2009–2010) for 2–5‐year‐old children (12.1%). Developing evidence‐based strategies for obesity prevention among Hispanic families remains a challenge.  相似文献   
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