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91.
Exposure to isocyanates has consistently been reported as the most common cause of occupational asthma. The objectives of this study were to assess how many Australian workers are currently exposed to isocyanates, identify the occupations with highest proportion of exposed workers and identify the main circumstances of exposures. Data comes from the Australian Workplace Exposure Study-Asthma, a national telephone survey which explored the prevalence of current occupational exposure to 227 asthmagens, grouped into 27 groups, among current Australian workers aged 18–65 years. A web-based tool, OccIDEAS, was used to collect job task information and to assign exposure to asthmagens, including isocyanates. Of the 4,878 eligible participants, 2.5% of them were deemed to be probably exposed to isocyanates at work in their current job (extrapolated to 3.0% of the Australian working population). The majority of those exposed were males (90.8%). The most common tasks undertaken that led to these exposures were using expanding foam fillers/sprays and isocyanate and/or polyurethane paints. Exposure occurred mainly among construction workers, wood workers, and painters or printers. This study investigating occupational exposure to isocyanates in a national working population provides information that can be used to inform the direction of occupational interventions and policies to decrease occupational asthma.  相似文献   
92.

Background

Trauma exposure has been linked to risky sexual behavior (RSB), but few studies have examined the impact of distinct trauma types on RSB in one model or how the association with trauma and RSB may differ across race.

Purpose

The objective of the current study was to examine the contribution of trauma exposure types to RSB—substance-related RSB and partner-related RSB identified through factor analysis—in young Black and White adult women.

Methods

We investigated the associations of multiple trauma types and RSB factor scores in participants from a general population sample of young adult female twins (n = 2,948). We examined the independent relationship between specific traumas and RSB, adjusting for substance use, psychopathology, and familial covariates. All pertinent constructs were coded positive only if they occurred before sexual debut.

Results

In Black women, sexual abuse was significantly associated with substance-related and partner-related RSB, but retained significance only for partner-related RSB in a fully adjusted model. For White women, sexual abuse and physical abuse were associated with both RSB factors in the base and fully adjusted models. Witnessing injury or death was only associated with RSBs in base models. For both groups, initiating alcohol (for Black women), alcohol, or cannabis (for White women) before sexual debut (i.e., early exposure) was associated with the greatest increased odds of RSB.

Conclusions

Data highlight the contribution of prior sexual abuse to RSBs for both White and Black women, and of prior physical abuse to RSBs for White women. Findings have implications for intervention after physical and sexual abuse exposure to prevent RSB, and thus, potentially reduce sexually transmitted infection/human immunodeficiency virus infection and unintended pregnancy in young women.  相似文献   
93.
BACKGROUND AND PURPOSE: The purpose of this study was to qualitatively explore clinical instructors' (CIs) perceptions of students' behaviors that comprise entry-level clinical performance, as well as how those perceptions were integrated into their decision making. SUBJECTS: The participants were 21 physical therapists who were CIs for physical therapist students. METHODS: Using a grounded theory approach, we conducted interviews, asking the question, "What is it about students' performance that makes you see them as entry-level therapists?" We determined common themes among the interviews and developed a schema to explain the decision-making process. RESULTS: Participants identified 7 attributes that, when demonstrated to a sufficient degree, illustrated to them students' ability to practice at the entry level. Those attributes were knowledge, clinical skills, safety, clinical decision making, self-directed learning, interpersonal communication, and professional demeanor. Participants viewed these attributes in concert to form a subjective "gut feeling" that a student demonstrated entry-level performance. A final theme emerged suggesting a definition of entry-level performance as "mentored independence." DISCUSSION AND CONCLUSION: Participants reported evaluating students' performance based on attributes similar to those suggested by the American Physical Therapy Association's Physical Therapist Clinical Performance Instrument and previous research. However, subjectivity also was involved in their decision about whether students were able to practice at the entry level. Participants also concluded that entry-level students need not be independent in all clinical situations.  相似文献   
94.
This article describes a preliminary qualitative evaluation of risk and protective factors associated with consistent contraceptive use and healthy sexual decision-making among ten of the first participants in the Prime Time intervention study. Prime Time is an 18-month intervention including one-on-one case management and peer educator training targeting sexually active 13-17-year-old girls who are recruited from health care clinics. Using an approach grounded in findings from previous research, social cognitive theory, and the social development model, Prime Time aims to improve participants' contraceptive use consistency, reduce number of sexual partners, and reduce unwanted sexual activity. Findings from this preliminary evaluation alert health care providers to the complex and dynamic nature of adolescent girls' sexual behaviors and to a broad range of risk and protective factors within individuals and their environments that may influence adolescent girls' sexual behaviors and contraceptive use. Findings suggest that an ongoing, supportive relationship with a case manager who is able to pace and tailor an intervention to the individual young person can have positive effects on adolescent girls' sexual behaviors and contraceptive use.  相似文献   
95.
OBJECTIVE: To determine the effect of creep developed in the anterior cruciate ligament and other viscoelastic knee structures on the function of the flexor and extensor muscles of males and females. DESIGN: Static load applied to the proximal tibia of young healthy male and female subjects in a laboratory setting with maximal voluntary knee flexion and extension performed before and after the load application. BACKGROUND: Static loads applied to various joints during occupational and sports activities are epidemiologically linked to higher than normal rates of disability reports. The physiological and biomechanical processes active in the development of such a neuromuscular disorder are not known. We hypothesize that creep developed in the anterior cruciate ligament due to prolonged static load will have pronounced impact on the reflexive activation of the associated musculature in a manner that may increase the risk of injury. Females are expected to be exposed to higher risk than males. METHODS: Male and female groups performed maximal voluntary knee flexion and extension before and after applying 200 and 150 N, respectively, to the proximal tibia for a 10 min period. Flexion and extension forces as well as electromyograph from agonist and antagonist muscles were measured at 35 degrees and 90 degrees knee flexion. Data was analyzed through repeated measures of analysis of variance. RESULTS: It was found that in extension, quadriceps electromyographic activity increased significantly after anterior cruciate ligament creep while hamstrings co-activation did not change. There was also a trend towards increased extension force after creep was developed, with significant effect of gender (larger increase in females). Similarly, significant increase in hamstrings electromyographic activity and a trend towards increased force during knee flexion was observed but with no effect of gender. Electromyographic spasms from the flexors and extensors were recorded in 30% of the subjects during the 10 min static loading period at 90 degrees angle and from the flexors only at 35 degrees. Creep in the ligament was marginally greater in females than in males with a significant effect of angle, being greater at 35 degrees than in 90 degrees knee flexion. CONCLUSIONS: The results suggest that ligament creep may develop a neuromuscular disorder consisting of spasms, increased electromyography and force in the agonist muscles without compensation from the antagonist. Static loading of a joint, therefore, may develop a neuromuscular disorder compounded with laxity of the ligaments and subject the individual to increased risk of injury. RELEVANCE: The data provides evidence that prolonged static loads applied to the anterior cruciate ligament and associated viscoelastic structures results in unbalanced muscular activation which puts individuals at increased exposure to injury. Work and sports activities should be scheduled while minimizing periods of static joint loading and emphasizing sufficient rest periods to allow recovery of creep and return to balanced muscular activation and co-activation.  相似文献   
96.
Living organ donors face direct costs when donating an organ, including transportation, lodging, meals, and lost wages. For those most in need, the National Living Donor Assistance Center (NLDAC) provides reimbursement to defray travel and subsistence costs associated with living donor evaluation, surgery, and follow‐up. While this program currently supports 9% of all US living donors, there is tremendous variability in its utilization across US transplant centers, which may limit patient access to living donor transplantation. Based on feedback from the transplant community, NLDAC convened a Best Practices Workshop on August 2, 2018, in Arlington, VA, to identify strategies to optimize transplant program utilization of this valuable resource. Attendees included team members from transplant centers that are high NLDAC users; the NLDAC program team; and Advisory Group members. After a robust review of NLDAC data and engagement in group discussions, the workgroup identified concrete best practices for administrative and transplant center leadership involvement; for individuals filing NLDAC applications at transplant centers; and to improve patient education about potential financial barriers to living organ donation. Multiple opportunities were identified for intervention to increase transplant programs’ NLDAC utilization and reduce financial burdens inhibiting expansion of living donor transplantation in the United States.  相似文献   
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The central importance of osteocytes in regulating bone homeostasis is becoming increasingly apparent. However, the study of these cells has been restricted by the relative paucity of cell line models, especially those of human origin. Therefore, we investigated the extent to which SaOS2 human osteosarcoma cells can differentiate into osteocyte-like cells. During culture under the appropriate mineralising conditions, SaOS2 cells reproducibly synthesised a bone-like mineralised matrix and temporally expressed the mature osteocyte marker genes SOST, DMP1, PHEX and MEPE and down-regulated expression of RUNX2 and COL1A1. SaOS2 cells cultured in 3D collagen gels acquired a dendritic morphology, characteristic of osteocytes, with multiple interconnecting cell processes. These findings suggest that SaOS2 cells have the capacity to differentiate into mature osteocyte-like cells under mineralising conditions. PTH treatment of SaOS2 cells resulted in strong down-regulation of SOST mRNA expression at all time points tested. Interestingly, PTH treatment resulted in the up-regulation of RANKL mRNA expression only at earlier stages of differentiation. These findings suggest that the response to PTH is dependent on the differentiation stage of the osteoblast/osteocyte. Together, our results demonstrate that SaOS2 cells can be used as a human model to investigate responses to osteotropic stimuli throughout differentiation to a mature osteocyte-like stage.  相似文献   
100.
To investigate the feasibility of noncontrast and contrast‐enhanced cone beam breast Computed Tomography (CT) in demonstrating malignant breast lesions in the diagnostic setting. This Institutional Review Board approved, Health Information Portability and Accountability Act compliant, prospective study enrolled BI‐RADS four and five patients from 2008 to 2010. Eighty‐seven subjects had noncontrast breast CT, 42 had contrast‐enhanced breast CT (CE‐breast CT) with 70 pathologically confirmed cancer diagnoses. All 70 comprise the study cohort for noncontrast breast CT, and 23 who had CE‐breast CT comprise the cohort for CE‐breast CT. All had diagnostic work‐up. Patient age, breast density, lesion size and characteristics, biopsy method, and core pathology were recorded. A Fisher's exact test was used to detect a difference in detectability. For agreement in size measurement between the imaging modalities, a paired t‐test was employed. Reported p‐values were based on 2‐sided tests. Two one‐sided tests were calculated to determine equivalence within ±0.3 cm at a 90% significance level. Noncontrast breast CT identified 67 of 70 malignant lesions, detected by diagnostic work‐up. CE‐breast CT identified 23 of 23 index malignant lesions and in addition, found three malignant lesions in three cases not previously detected. Noncontrast breast CT demonstrated the index lesion in 67 of 70 cases and CE‐breast CT demonstrated the index lesion in all 23 cases. An additional three new malignant lesions not seen with conventional diagnostic work‐up were detected. In this preliminary study, breast CT with or without contrast was shown to be accurate at identifying malignant breast lesions in the diagnostic setting.  相似文献   
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