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91.
The authors relate their statistic about mesenteric infarction in the last five years and they get out the starting point in order to check the characteristics of a disease, which is today distinguished by an infaust prognosis. After few mentions about etiopathology and pathologic anatomy they keep their attention on clinic manifestations of disease and on diagnostic research. After dealing with medical and surgical therapy they declare how more refined diagnostic technique could help early diagnosis and consequently decrease morbidity and morbidity, which are completely unacceptable.  相似文献   
92.
AIM: To assess the efficacy and safety of a heavy silicone oil (Densiron 68) in the management of inferior retinal detachment recurrence. METHODS: A retrospective non-comparative consecutive case series study. Forty-nine cases of complex inferior retinal detachment were treated using Densiron 68 heavy silicone oil (HSO) as the endotamponade. Our main purpose was anatomic reattachment following Densiron 68 removal. Functional outcomes, rate of recurrences, the presence of inflammatory complications and intraocular pressure alterations were evaluated. RESULTS: Forty-nine patients affected by complex retinal re-detachment were recruited. The mean follow-up was 7.6 (±1.5) mo. The mean best corrected visual acuity after Densiron 68 removal was 0.95 logMAR, standard error (SE: 0.068). Retinal reattachment was 61.2% after first surgery and 81.6% after second surgery. Nineteen cases (38.8%) had recurrences when intraocular heavy silicon oil was in situ, 26.3% (5 cases) of which involved the inferior retina. CONCLUSION: Densiron 68 ef?ciently fills the inferior retinal periphery and might lower the risk of inferior proliferative vitreoretinopathy development, in particular after a standard silicon oil tamponade that reduces the proliferative process in the upper quadrants of the retina.  相似文献   
93.
Metastatic triple-negative breast cancer (mTNBC) represents 15% of invasive breast cancers. Prognosis is poor, and there is no specific target therapy but biological agents combined with chemotherapy may be effective.  相似文献   
94.
PURPOSE: Although tumor resection is the mainstay of treatment for localized neuroblastoma, there are no established guidelines indicating which patients should be operated on immediately and which should undergo surgery after tumor reduction with chemotherapy. In an effort to develop such guidelines, the LNESG1 study defined surgical risk factors (SRFs) based on the imaging characteristics. PATIENTS AND METHODS: A total of 905 patients with suspected localized neuroblastoma were registered by 10 European countries between January 1995 and October 1999; 811 of 905 patients were eligible for this analysis. RESULTS: Information on SRFs was obtained for 719 of 811 patients; 367 without and 352 with SRFs. Of these 719 patients, 201 patients (four without and 197 with SRFs) underwent biopsy only. An attempt at tumor excision was made in 518 patients: 363 of 367 patients without and 155 of 352 patients with SRFs (98.9% v 44.0%). Complete excision was achieved in 271 of 363 patients without and in 72 of 155 patients with SRF (74.6% v 46.4%), near-complete excision was achieved in 81 and 61 patients (22.3% v 39.3%), and incomplete excision was achieved in 11 and 22 patients (3.0% v 14.2%), respectively. There were two surgery-related deaths. Nonfatal surgery-related complications occurred in 45 of 518 patients (8.7%) and were less frequent in patients without SRFs (5.0% v 17.4%). Associated surgical procedures were also less frequent in patients without SRFs (1.6% v 9.7%). CONCLUSION: The adoption of SRFs as predictors of adverse surgical outcome was validated because their presence was associated with lower complete resection rate and greater risk of surgery-related complications. Additional studies aiming to better define the surgical approach to localized neuroblastoma are warranted.  相似文献   
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96.
The bonding of steel/fiber-reinforced polymer (SRP/FRP) laminate strips to concrete/masonry elements has been found to be an effective and efficient technology for improving the elements’ strength and stiffness. However, premature laminate–substrate debonding is commonly observed in laboratory tests, which prevents the laminate from reaching its ultimate strength, and this creates uncertainty with respect to the level of strengthening that can be achieved. Therefore, for the safe and effective application of this technology, a close estimate of the debonding load is necessary. Towards this end, in this paper, a new, relatively simple, semi-analytic model is presented to determine the debonding load and the laminate stress and deformation, as well as the interfacial slip, for concrete substrates bonded to SRP/FRP and subjected to monotonic or cyclic loading. In the model, a bond-slip law with a linearly softening branch is combined with an elasto-plastic stress-strain relationship for SRP. The model results are compared with available experimental data from single-lap shear tests, with good agreement between them.  相似文献   
97.
Toll-like receptor 2 (TLR2) ligands are attracting attention as prophylactic and immunopotentiator agents against pathogens, including viruses. We previously reported that a synthetic diacylated lipopeptide (Mag-Pam2Cys_P48) polarized porcine macrophages towards a proinflammatory antimicrobial phenotype. Here, we investigated its role in modulating monocyte-derived macrophage (moMΦ) responses against African swine fever virus (ASFV), the etiological agent of one of the greatest threats to the global pig industry. Two ASFV isolates were compared: the attenuated NH/P68 and the virulent 26544/OG10. No effect on virus infection nor the modulation of surface markers’ expression (MHC I, MHC II DR, CD14, CD16, and CD163) were observed when Mag-Pam2Cys_P48 treated moMΦ were infected using a multiplicity of infection (MOI) of 1. Mag-Pam2Cys_P48 treated moMΦ released higher levels of IL-1α, IL-1β, IL-1Ra, and IL-18 in response to infection with NH/P68 ASFV compared to 26544/OG10-infected and mock-infected controls. Surprisingly, when infected using a MOI of 0.01, the virulent ASFV 26544/OG10 isolate replicated even slightly more efficiently in Mag-Pam2Cys_P48 treated moMΦ. These effects also extended to the treatment of moMΦ with two other lipopeptides: Mag-Pam2Cys_P80 and Mag-Pam2Cys_Mag1000. Our data suggested limited applicability of TLR2 agonists as prophylactic or immunopotentiator agents against virulent ASFV but highlighted the ability of the virulent 26544/OG10 to impair macrophage defenses.  相似文献   
98.
Anti-Black racism remains a pervasive crisis in the United States. Racist social systems reinforce racial inequalities and perpetuate prejudicial beliefs. These beliefs emerge in childhood, are difficult to change once entrenched in adolescence and adulthood, and lead people to support policies that further reinforce racist systems. Therefore, it is important to identify what leads children to form prejudicial beliefs and biases and what steps can be taken to preempt their development. This study examined how children’s exposure to and beliefs about racial inequalities predicted anti-Black biases in a sample of 646 White children (4 to 8 years) living across the United States. We found that for children with more exposure to racial inequality in their daily lives, those who believed that racial inequalities were caused by intrinsic differences between people were more likely to hold racial biases, whereas those who recognized the extrinsic factors underlying racial inequalities held more egalitarian attitudes. Grounded in constructivist theories in developmental science, these results are consistent with the possibility that racial biases emerge in part from the explanatory beliefs that children construct to understand the racial inequalities they see in the world around them.

In the United States today, the perpetuation of racial bias, prejudice, and discrimination maintain and reflect racist social systems that systematically advantage White people while systematically disadvantaging Black, Indigenous, and other people of color (13). One critical step to redressing this injustice is understanding the psychological processes that lead to the formation of racist thoughts and actions (4, 5). However, little is known about the developmental mechanisms that underlie the emergence of these thoughts and actions. Given the scale and scope of racial bias in the United States, there are undoubtedly multiple social and psychological processes involved; for example, experiences with intergroup contact explains ∼4% of variation in bias (5, 6). In the present study, we examined an additional mechanism that we hypothesize underlies the development of anti-Black bias in White children living across the United States: children’s exposure to and explanatory beliefs about racial inequalities. We expected that children who have had more exposure to racial inequalities in their daily lives (i.e., older children living in neighborhoods with larger disparities between Black and White people) would hold racial biases reflective of their beliefs about those inequalities. Specifically, we expected that children who believe that racial inequalities are caused by intrinsic differences between people would have more racial biases because they are coming to view race and status as inherently linked, whereas children who believe that inequalities are caused by extrinsic factors would have fewer racial biases because of the recognition that it would be unfair and inaccurate to judge people based on these extrinsic circumstances. To shed light on this mechanism, we assessed children’s endorsement of intrinsic and extrinsic explanations for racial inequalities, children’s exposure to racial inequality in their residential ZIP code (i.e., Black/White disparities in income and education with children’s age as a measure of the duration of exposure), and children’s racial biases using two standard assessments of bias in childhood (i.e., children’s choice to play with and attitudes about peers from different racial backgrounds (714)). We then examined how children’s exposure to and beliefs about racial inequalities interact to predict variation in anti-Black bias during childhood.Explicit anti-Black biases emerge early and continue to develop throughout childhood (12). By 4 to 5 years of age, children—and White children in particular—hold more negative attitudes toward Black than White peers, attribute more negative intentions to Black than White peers, and are less likely to form friendships with Black than White peers (714). These biases are consequential. The majority of Black children and adolescents report experiencing racial prejudice and discrimination and suffer from increased stress, decreased social belonging, and restricted educational and extracurricular opportunities because of these experiences (1517). Early emerging biases also serve as the developmental roots for the racial bias, prejudice, and discrimination that become deeply entrenched in adolescence and adulthood and lead people to support racist social policies (1820). Importantly, there is also substantial individual variation in the early development of racial bias; some children develop more racial biases than do others (12, 13). Early childhood is therefore an ideal time for disrupting the formation of problematic beliefs; by understanding the predictors of this individual variation (i.e., why some children develop more biases than others) at a time when children’s beliefs are emerging and particularly sensitive to new experiences, we can better inform future efforts to understand and disrupt the formation of racial biases before they become deeply entrenched.In the present study, we used an online platform for conducting remote, unmoderated psychological research with children (21) to examine the environmental and psychological factors that predict the development of anti-Black bias in a sample of 646 White children 4- to 8-years-old (300 female, 346 male) living across the United States. We focused on White children in this age range because they are particularly likely to develop anti-Black biases and hold disproportionate power and influence over social contexts by virtue of their racial privilege (35, 12, 13). Children participated from 464 unique ZIP codes representing 47 different states; this degree of cultural, geographic, and socioeconomic diversity allowed for an analysis of the variance in children’s environment that is not possible with traditional, in-person approaches to developmental science. Using the online platform, children completed the study independently from their home computer without interacting with a researcher, reducing concerns for self-presentation. Research sessions were recorded via the computer’s webcam for subsequent coding.  相似文献   
99.
100.
Sarcopenia (SP) is a syndrome characterized by age-associated loss of skeletal muscle mass and function. SP worsens both acute and late radiation-induced toxicity, prognosis, and quality of life. Myosteatosis is a pathological infiltration of muscle tissue by adipose tissue which often precedes SP and has a proven correlation with prognosis in cancer patients. Sarcopenic obesity is considered a “hidden form” of SP (due to large fat mass) and is independently related to higher mortality and worse complications after surgery and systemic treatments with worse prognostic impact compared to SP alone. The evaluation of SP is commonly based on CT images at the level of the middle of the third lumbar vertebra. On this scan, all muscle structures are contoured and then the outlined surface area is calculated. Several studies reported a negative impact of SP on overall survival in patients undergoing RT for tumors of the head and neck, esophagus, rectum, pancreas, cervix, and lung. Furthermore, several appetite-reducing side effects of RT, along with more complex radiation-induced mechanisms, can lead to SP through, but not limited to, reduced nutrition. In particular, in pediatric patients, total body irradiation was associated with the onset of SP and other changes in body composition leading to an increased risk of cardiometabolic morbidity in surviving adults. Finally, some preliminary studies showed the possibility of effectively treating SP and preventing the worsening of SP during RT. Future studies should be able to provide information on how to prevent and manage SP before, during, or after RT, in both adult and pediatric patients.  相似文献   
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