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81.
In many animal studies, acute treatment with the novel anxiolytic agent buspirone exhibits only minimal anxiolytic efficacy (i.e., increases in punished responding) when compared to benzodiazepines and barbiturates. The present studies examined the effects of acute pre-test challenges with buspirone in subjects receiving chronic post-test buspirone or saline treatments. Chronic post-test treatment with buspirone (4 mg/kg/day for 4 weeks, followed by 8 mg/kg/day for 12 weeks) did not significantly affect CSD behavior. Consistent with previous reports, acute pre-test administration of buspirone (0.125–2 mg/kg, IP) to subjects receiving chronic post-test saline treatment resulted in only a modest anti-conflict effect in the CSD paradigm (approximately ten shocks over control). In contrast, subjects chronically treated with buspirone exhibited a dramatically greater anti-conflict effect following acute challenge with buspirone (up to 40 shocks over control). These data are consistent with the hypothesis that the full anxiolytic efficacy of buspirone requires repeated administration.  相似文献   
82.
This study addressed the efficacy of cognitive-behavioral therapy (CBT), relative to minimal contact control (MCC), in a sample of 85 older adults (age 60 years and over) with generalized anxiety disorder (GAD). All participants completed measures of primary outcome (worry and anxiety), coexistent symptoms (depressive symptoms and specific fears), and quality of life. Results of both completer and intent-to-treat analyses revealed significant improvement in worry, anxiety, depression, and quality of life following CBT relative to MCC. Forty-five percent of patients in CBT were classified as responders, relative to 8% in MCC. Most gains for patients in CBT were maintained or enhanced over 1-year follow-up. However, posttreatment scores for patients in CBT failed to indicate return to normative functioning.  相似文献   
83.
84.
Effect of depressive symptoms on survival after heart transplantation   总被引:3,自引:0,他引:3  
OBJECTIVE: This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated. METHOD: An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome. RESULTS: Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables. CONCLUSIONS: Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated.  相似文献   
85.
86.
The examination of physical environments to explain and promote physical activity is an important yet under-investigated area of research inquiry. This study explored relationships between the perceived availability of physical environmental resources and the perceived importance of these resources in relation to physical activity levels amongst youth. A self-report questionnaire was completed by 610 students (mean age = 15.5 years old; 62% female participants) from four high schools (grades 9-12) in rural Alberta, Canada. Perceived physical environment constructs explained 5% of the variance in physical activity, with home, neighborhood, and school as significant domains. Perceived importance constructs explained 8% of the variance in physical activity with school context showing the only significant relationship with physical activity. A hierarchical regression analysis entered sex, grade, self-efficacy, peer, family and physical education teacher relationships, as the first block and eight environmental constructs as the second block. The first block variables accounted for 22% of the variance and environmental constructs accounted for an added 4% of the variance in physical activity. Perceived importance of the school environment was the only environment variable significantly associated with physical activity (β = .14; p < .05) after taking into account the impact of these traditional predictors. These findings reinforce the need to provide and support school physical environments related to physical activity.  相似文献   
87.
The data for 197 mother-infant pairs from two longitudinal studies were analyzed to assess relations between maternal attachment representations; atypical maternal behavior, coded with a new tool. Atypical Maternal Behavior Instrument for Assessment and Classification (AMBIANCE), and infant attachment. Both maternal and infant attachment were systematically related to atypical maternal behavior: mothers who were Unresolved on the Adult Attachment Interview and those whose infants were disorganized in the Strange Situation Procedure engaged in more atypical behaviors than those who were not Unresolved and whose infants showed organized patterns of attachment, respectively. Regression analyses indicated that when tested as a mediator, atypical maternal behavior as measured on the AMBIANCE did not reduce the association between maternal Unresolved status and infant disorganized attachment. This may, in part, reflect the fact that our low-risk sample did not include enough cases in the risk categories. These data provide preliminary empirical validation for the AMBIANCE and strengthen the evidence for links between atypical maternal behavior and disorganized attachment but indicate that in addition to maternal attachment representations, other factors must contribute to atypical maternal behavior.  相似文献   
88.
Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community.  相似文献   
89.
A uterine leiomyosarcoma that became positive for HMB45 in the metastasis   总被引:1,自引:0,他引:1  
Uterine smooth muscle tumors are usually spindle cell lesions, but a minority is composed of epithelioid cells. Foci of clear cells can be found in these latter tumors. Recently, it has been shown that some of these tumors can be positive for HMB45, and some authors have advocated calling these lesions perivascular epithelioid cell (PEC) tumors or PEComas. The case we describe here clearly shows that the so called PEC is just a smooth muscle cell capable of changing its immunophenotype. The patient involved is a 29-year-old black woman who was found to have an epithelioid leiomyosarcoma of the uterus in November 1995. She was treated with a simple hysterectomy and bilateral salpingo-oophorectomy. A metastatic lesion was found in her liver. She, therefore, also received chemotherapy and was free of disease until October 2002, when a recurrent tumor was detected in her spine. After undergoing resection of the lesion at 2 different times, in 2002 and 2003, the patient was treated with radiotherapy and is currently receiving chemotherapy. On microscopic examination, the tumor in the uterus and liver both proved to be an epithelioid leiomyosarcomas that was diffusely positive for smooth muscle actin. Approximately 15% of the cells had clear cytoplasm, but sections from 2 different blocks were completely negative for HMB45. However, although the tumors resected from the spine in 2002 and 2003 showed features similar to those of the uterine neoplasm, but with a lower percentage of cells positive for smooth muscle actin and more clear cells, several of the clear cells were positive for HMB45. To the best of our knowledge, this is the first case of a uterine smooth muscle cell tumor that became positive for HMB45 when it metastasized.  相似文献   
90.
There is considerable variation in care provided to patients with diabetes related to metabolic control, preventive services, and degree of patient-centered support. This study evaluates the relation of self-determination theory (SDT) constructs of clinician autonomy support, and patient competence to glycemic control, depressive symptoms, and patient satisfaction from baseline surveys of 634 patients of 31 Colorado primary care physicians participating in a program to improve diabetes care. Spearman correlations of autonomy support from one's clinician with patient competence, HbA1c, depressive symptoms and satisfaction were significant (R = -0.11 to 0.55, P < 0.005). Structural equation modeling demonstrated that autonomy support was significantly related to perceived competence, depressive symptoms, patient satisfaction, and indirectly to glycemic control. Perceived competence was significantly related to depressive symptoms, patient satisfaction and glycemic control. Further, the motivation constructs from SDT accounted for 5% of the variance in glycemic control, 8% of the variance in depression, and 42% of the variance in patient satisfaction. Quality improvement efforts need to pay greater attention to patient competence, satisfaction, and depression, in addition to glycemic control. Clinician autonomy support was found to be reliably measured and moderately correlated with psychosocial and biologic outcomes related to diabetes self-management. These results suggest training clinicians to increase their support of patient autonomy may be one important avenue to improve diabetes outcomes.  相似文献   
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