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1.
Within the human T-cell receptor delta (TCRD) gene we have identified a new cluster of seven delta recombining elements (deltaRec2.1-2.7), located 2.6-5.2 kilobases downstream of the Vdelta2 gene segment. The deltaRec2 elements are isolated recombining signal sequences (RSS), which were shown to rearrange with the Ddelta3 and Jdelta1 segments of the TCRD gene as well as with the psiJalpha of the TCRA gene. Rearrangements involving the deltaRec2 elements were found in all peripheral blood (PB) samples from 10 healthy individuals, although their frequency was about 100-fold lower than that of classical deltaRec rearrangements. The total frequency of deltaRec2 rearrangements was lower in PB T lymphocytes, as compared with thymocytes, suggesting that they are deleted during T-cell development. The decrease of the frequency of the deltaRec2-Ddelta3 rearrangements was most prominent: 11 times lower in PB T lymphocytes than in thymocytes. Since the deltaRec2-Jdelta1 rearrangements contained the Ddelta3 segment in the junctional region, we assume that they are derived from the deltaRec2-Ddelta3 rearrangements. In contrast, the majority of deltaRec2-psiJalpha rearrangements did not contain the Ddelta3 segment, indicating that they are single step rearrangements. The deltaRec2-Jdelta1 and deltaRec2-psiJalpha rearrangements seem to be T-lineage specific, but the deltaRec2-Ddelta3 rearrangements were also found at very low frequencies in B lymphocytes and natural killer cells. Our results suggest that deltaRec2 rearrangements are transient steps in the recombinatorial process of the TCRAD locus and are probably deleted by subsequent Valpha-Jalpha rearrangements. We hypothesize, that in a similar manner to the classical deltaRec rearrangements, the deltaRec2 rearrangements might also contribute to T-cell differentiation towards the TCR-alphabeta lineage.  相似文献   
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This study examines problem behavior over time in 59 boys with fragile X syndrome (FXS), aged 4-12 years, using the Child Behavior Checklist (CBCL). Approximately 49% of the boys scored within the borderline or clinical range on total problem behavior, while 56-57% scored in the borderline or clinical range on the attention and thought problems subscales, and 26% scored in this range on the social problems subscale. With a mean of 2.5 assessments per child, behavior problems were stable during the 3-year period of study. Total problem behavior was higher for children who displayed autistic behavior, were rated as low in adaptability, had mothers with higher maternal education levels, and were on medication. Mothers with more education also rated their children as having more attention, thought, and total problems. Children taking medication differed from boys who were not taking medication on social problems, but not on attention and thought problems. Low adaptability and more autistic characteristics predicted thought problems.  相似文献   
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This study examined risk and protective factors that differentiate low-income, abused African American women (N = 200) who attempted suicide from those who had never made a suicide attempt. Results from multivariate analyses revealed that numerous and/or severe negative life events, a history of child maltreatment, high levels of psychological distress and depression, hopelessness about the future, and alcohol and drug problems were factors associated with attempter status. Protective factors associated with nonattempter status included hopefulness, self-efficacy, coping skills, social support, and effectiveness in obtaining material resources. Culturally competent intervention approaches for abused women should target increasing their protective factors and reducing their risk factors to decrease the likelihood that these women engage in suicidal behavior.  相似文献   
4.
Autoantibodies in sera from patients with systemic lupus erythematosus (SLE) and onchocerciasis recognize calreticulin (CaR), a calcium-binding protein, as antigen. In this study we present the immunological properties of two synthetic peptides prepared to correspond to the 1-24 and 7-24 amino acid sequence of CaR. In contrast to information previously reported for the recombinant protein, the CaR-peptide analogues appeared immunoreactive to anti-Ro/SSA autoimmune sera. Human sera from patients with SLE, Sjögren's syndrome (SS), rheumatoid arthritis (RA), as well as mixed connective tissue disease (MCTD), demonstrated a positive autoimmune response (binding of antibodies), to the CaR-peptide analogues. These findings suggest that anti-calreticulin autoantibodies are not restricted to any disease specificity.  相似文献   
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Mothers who breastfeed typically exhibit lower levels of depressive symptomatology than mothers who do not. However, very few studies have investigated the directionality of this relationship. Of the prospective studies published, all but one focus exclusively on whether maternal depression reduces rates of subsequent breastfeeding. This study again examines this relationship, but also the reverse—that breastfeeding might predict lower levels of later depression. Using multilevel modeling, we investigated the relationship between breastfeeding and self-reported depressive symptomatology in 205 women followed prenatally and at 3, 6, 12, and 24 months after birth. Consistent with previous research, women with prenatal depressive symptomatology weaned their infants 2.3 months earlier, on average, than women without such symptomatology. We also found, however, that women who breastfed more frequently at 3 months postpartum showed greater subsequent declines in depressive symptomatology over time compared to women who breastfed less frequently, resulting in lower absolute levels of depressive symptoms by 24 months postpartum, controlling for important confounds. In sum, these findings are consistent with a bidirectional association between breastfeeding and depression, with prenatal depression predicting less breastfeeding soon after birth and breastfeeding predicting declines in maternal depression up to 2 years after birth. We discuss mechanisms that could potentially explain these associations and avenues for future research.  相似文献   
7.
The determination of carbohydrate-deficient transferrin (CDT) in serum has been found useful as a marker of increased alcohol consumption of >60 g/day. It is not clear why the reference range is different for women (0 to 26 units/liter) and men (0 to 20 units/liter). We evaluated serum COT in 286 healthy subjects (209 women, 77 men) using a commercially available radioimmunoassay. Premenopausal women had higher CDT levels than postmenopausal women, whereas no age-related difference of CDT levels was found in men. In postmenopausal women, higher CDT levels were associated with estrogen replacement therapy. In premenopausal women, however, neither the phase of the menstrual cycle nor contraceptive steroid use showed a significant association with the increase in CDT levels. No significant correlations were found between CDT and either serum estradiol or serum iron. In conclusion, both premenopausal state and postmenopausal estrogen replacement therapy seem to increase serum levels of CDT. Therefore, menopausal status and exogenous estrogens should be considered when interpreting CDT values in women.  相似文献   
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Violence, a leading cause of injuries and death, is recognized as a major public health problem. In 1996, injuries were the second leading cause of hospitalizations in Jamaica. The estimated annual cost of in-patient care for injuries was 11.6 million US dollars. To develop strategies to reduce the impact of violence-related injuries on Jamaican health care resources, the Ministry of Health, Division of Health Promotion and Protection (MOH/DHPP) in collaboration with the Centers for Disease Control and Prevention and the Tropical Metabolic Research Institute, University of the West Indies Mona, designed and implemented a violence-related injury surveillance system (VRISS) at Kingston Public Hospital (KPH). In 1998, the VRISS, based on the International Classification of External Cause of Injury (ICECI), was implemented in the accident and emergency (A&E) department of Jamaica's tertiary care hospital, KPH. VRISS collects demographic, method and circumstance of injury, victim-perpetrator relationship and patient's discharge status data. From 8/1/98 to 7/31/99, data on 6,107 injuries were collected. Injuries occurred primarily among males aged 25-44 years. Most injuries (54%; 3171) were caused by use of a sharp object. Nearly half (49%; 2992) were perpetrated by acquaintances. The majority, 70% (4,252), were the result of a fight or argument and 17% were admitted to the hospital. The VRISS utilized A&E department data to characterize violence-related injuries in Jamaica, a resource-limited environment. These data will be used to guide intervention development to reduce violence-related injuries in Jamaica.  相似文献   
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