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排序方式: 共有182条查询结果,搜索用时 15 毫秒
1.
Summary Homologs of the herpes simplex virusgB gene were identified in two -herpesviruses of platyrrhine monkeys, Herpesvirus saimiri 1 (HVS 1) and H. ateles 1 (HVA 1). These genes were cloned and sequenced in their entirety. Analysis of the predicted amino acid sequences indicated that the gB glycoproteins of these two viruses are of similar size, have 10 Cys residues and 5 potential N-linked glycosylation sites which align exactly with those in other primate -herpesvirus gB polypeptides, and have a similar distribution of predicted secondary structural features, all of which indicate a conserved structure of the gB polypeptide. Alignment of these two gB sequences with those of four other primate -herpesviruses (SA 8, B virus, HSV 1 and HSV 2) revealed localized regions of extensive sequence divergence as well as highly conserved regions. On comparison of the six primate virus gB sequences, the gBs of the two platyrrhine monkey viruses form a subgroup separate from that of the four catarrhine virus gBs. The degree of relatedness of the HVA 1 and HVS 1 gB sequences to each other was equivalent to the degree of relatedness between the human and the cercopithecine monkey virus gB sequences. 相似文献
2.
Michael S. Businelle Darla E. Kendzor Carla J. Rash Scott M. Patterson Scott F. Coffey Amy L. Copeland 《Substance use & misuse》2013,48(7):905-914
The Gambling Task (GT) has demonstrated sensitivity to a type of decision-making that differentiates individuals manifesting substance use disorders from those without such disorders. However, studies have not yet compared the GT performance of “heavy smokers” to the performance of never-smokers. In the present study, the GT performance of “heavy smokers” (n = 39) and never-smokers (n = 32) recruited from the community was compared in an experimental design. Analysis of covariance showed that “heavy smokers” performance on the GT was significantly worse than that of never-smokers (p < .01). Implications, the study's limitations and future directions are discussed. 相似文献
3.
Michael S. Businelle Ph.D. Darla E. Kendzor Ph.D. Lorraine R. Reitzel Ph.D. Jennifer Irvin Vidrine Ph.D. Yessenia Castro Ph.D. Patricia Dolan Mullen Dr.P.H. Mary M. Velasquez Ph.D. Ludmila Cofta-Woerpel Ph.D. Paul M. Cinciripini Ph.D. Anthony J. Greisinger Ph.D. David W. Wetter Ph.D. 《Annals of behavioral medicine》2013,45(2):180-191
Background
Low socioeconomic status (SES) exacerbates the high rate of smoking relapse in women following childbirth.Purpose
This study examined multiple models of potential mechanisms linking SES and postpartum smoking relapse among women who quit smoking due to pregnancy.Methods
Participants were 251 women enrolled in a randomized clinical trial of a new postpartum smoking relapse prevention intervention. Four models of the prepartum mechanisms linking SES and postpartum smoking relapse were evaluated using a latent variable modeling approach.Results
Each of the hypothesized models were a good fit for the data. As hypothesized, SES indirectly influenced postpartum smoking relapse through increased prepartum negative affect/stress, reduced sense of agency, and increased craving for cigarettes. However, the model that included craving as the sole final pathway between SES and relapse demonstrated superior fit when compared with all other models.Conclusions
Findings have implications for future interventions that aim to reduce postpartum relapse. 相似文献4.
Insiya B. Poonawalla Darla E. Kendzor Margaret Tresch Owen Margaret O. Caughy 《Addictive behaviors》2014
Background
Although childhood socioeconomic disadvantage has been linked with adolescent tobacco and alcohol use in cross-sectional research, less is known about the influence of changes in socioeconomic status during childhood. Upward socioeconomic mobility may attenuate the negative influence of earlier socioeconomic disadvantage on health, while downward mobility may counter the health benefits of earlier socioeconomic advantage. This study evaluated the influence of common trajectories of family income during childhood on smoking and alcohol use during adolescence.Methods
Data utilized were part of the 15-year longitudinal Study of Early Child Care and Youth Development. A 5-class trajectory model (two stable, one downward, and two upward income trajectories) was developed previously with this sample (N = 1356). Logistic regression analyses were conducted to determine whether children of the more disadvantaged income trajectories were more likely to engage in tobacco and alcohol use at age 15 relative to those of the most advantaged trajectory.Results
Family income trajectory was significantly associated with ever-smoking (p = .02) and past-year alcohol use at age 15 years (p = .008). Children from the less advantaged trajectories were more likely to have ever-smoked than children of the most advantaged trajectory (all p's < .05). Children of the downwardly mobile trajectory were more likely to have used alcohol within the past year than children of the most advantaged trajectories as well as the most disadvantaged trajectory (all p's < .05).Conclusions
Findings indicate that childhood socioeconomic disadvantage influences adolescent smoking, while downward socioeconomic mobility influences adolescent alcohol use. 相似文献5.
Jose Ramon Fernandez-Alvarez Rashmi Shreyans Gandhi Philip Amess Liam Mahoney Ryan Watkins Heike Rabe 《European journal of pediatrics》2014,173(1):93-98
Despite the paucity of evidence, the practice of weaning nasal continuous positive airway pressure (NCPAP) is widespread. However, the most clinically effective non-invasive ventilatory support strategy remains to be determined. We compared the outcome of very premature infants with respiratory distress syndrome treated with a combination of NCPAP and heated humidified high-flow nasal cannula (HHFNC) versus NCPAP and low-flow nasal cannula (LFNC). Between 2004 and 2008, patients ≤28 weeks of gestation and <1,250 g of birth weight were treated with NCPAP + HHFNC or NCPAP + LFNC. Their respiratory and non-respiratory outcome including cost-effectiveness was compared after matching for antenatal steroid doses, mode of delivery, birth plurality, gestational age, birth weight, gender, surfactant doses, length of mechanical ventilation and clinical risk index for babies-II (CRIB-II) score. Thirty-nine infants received HHFNC + NCPAP, and 40 received NCPAP + LFNC. Median gestational age and birth weight were 27 weeks and 930 g and 27 weeks and 980 g, respectively. The total number of NCPAP days was significantly reduced by 50 % in the HHFNC group. Thirteen percent of the patients on NCPAP suffered from nasal bridge lesions compared to none on HHFNC. Respiratory and non-respiratory outcome was not significantly different otherwise. Combination of NCPAP and HHFNC reduced costs by 33 %. Conclusions: HHFNC shortens NCPAP time without increasing overall length of non-invasive respiratory support in very preterm infants. Unlike NCPAP, HHFNC does not seem to increase the risk of nasal trauma and appears to improve cost-effectiveness whilst producing otherwise equal respiratory and non-respiratory outcomes. 相似文献
6.
NMDA antagonists may be useful for their potential to increase or prolong opioid analgesia while attenuating the development of opioid tolerance and dependence. The purpose of this study was to determine whether there are sex differences in NMDA antagonist modulation of morphine antinociception. Adult female and male Sprague–Dawley rats were injected s.c. with saline or one dose of MK-801 (0.005, 0.01, 0.02, or 0.04 mg/kg), dextromethorphan (5, 10, or 20 mg/kg), or LY235959 (0.5, 1.0, or 2.0 mg/kg) in combination with saline or one dose of morphine (1.8, 3.2, or 5.6 mg/kg), and tested on the 50 °C hotplate and tail withdrawal assays 15–120 min post-injection. At the doses examined, only LY235959 produced any antinociception when administered alone. MK-801 attenuated morphine antinociception on both assays, but only at sporadic (inconsistent) dose-combinations. Dextromethorphan increased morphine antinociception on the hotplate but not tail withdrawal assay, at all three morphine doses in males, but only the higher morphine doses in females. In contrast, LY235959 modulated morphine antinociception on both assays; the lowest dose attenuated, and higher doses enhanced morphine antinociception, but the particular morphine doses and assay in which these effects occurred depended on the sex of the subject. Thus, all three NMDA antagonists modulated morphine antinociception in female and male rats, but the direction of this modulation depended on the particular antagonist examined, the nociceptive test, the dose of antagonist and of morphine, and time post-injection. 相似文献
7.
Background
We have previously shown that use of an EC brush device in combination with the Rovers Cervex-Brush (SurePath broom) offered no significant improvement in EC recovery. Here we determine if use of additional collection devices enhance the diagnostic utility of the SurePath Pap for gynecologic cytology. 相似文献8.
9.
Detecting protein-protein interactions in vesicular stomatitis virus using a cytoplasmic yeast two hybrid system 总被引:1,自引:0,他引:1
Moerdyk-Schauwecker M Destephanis D Hastie E Grdzelishvili VZ 《Journal of virological methods》2011,173(2):203-212
Protein-protein interactions play an important role in many virus-encoded functions and in virus-host interactions. While a “classical” yeast two-hybrid system (Y2H) is one of the most common techniques to detect such interactions, it has a number of limitations, including a requirement for the proteins of interest to be relocated to the nucleus. Modified Y2H, such as the Sos recruitment system (SRS), which detect interactions occurring in the cytoplasm rather than the nucleus, allow proteins from viruses replicating in the cytoplasm to be tested in a more natural context. In this study, a SRS was used to detect interactions involving proteins from vesicular stomatitis virus (VSV), a prototypic non-segmented negative strand RNA (NNS) virus. All five full-length VSV proteins, as well as several truncated proteins, were screened against each other. Using the SRS, most interactions demonstrated previously involving VSV phosphoprotein, nucleocapsid (N) and large polymerase proteins were confirmed independently, while difficulties were encountered using the membrane associated matrix and glycoproteins. A human cDNA library was also screened against VSV N protein and one cellular protein, SFRS18, was identified which interacted with N in this context. The system presented can be redesigned easily for studies in other less tractable NNS viruses. 相似文献
10.
Darla E. Kendzor Michael S. Businelle Carlos A. Mazas Ludmila M. Cofta-Woerpel Lorraine R. Reitzel Jennifer Irvin Vidrine Yisheng Li Tracy J. Costello Paul M. Cinciripini Jasjit S. Ahluwalia David W. Wetter 《Journal of behavioral medicine》2009,32(6):545-557
Although socioeconomic status is a major contributing factor to health disparities, the mechanisms through which socioeconomic status influences health remain unclear. The purpose of the present study was to evaluate an a priori conceptual model of the pathways between socioeconomic status and modifiable health risk factors in a sample of 399 African Americans seeking smoking cessation treatment. A latent variable modeling approach was utilized to characterize the interrelationships among socioeconomic status, neighborhood disadvantage, social support, negative affect/perceived stress, and three specific modifiable risk factors (i.e., overweight/obesity, insufficient physical activity, at-risk drinking). Findings indicated that neighborhood disadvantage, social support, and negative affect/perceived stress function as pathways linking socioeconomic status and modifiable risk factors among African American smokers, and negative affect/perceived stress appears to play a key mediating role. Policy, community, and individual-level interventions may attenuate the impact of socioeconomic status on health by targeting intermediate psychosocial, environmental, and behavioral pathways. 相似文献