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Recognition of self protein epitopes, apart from those engaged in idiotypic network interactions and MHC restriction, is probably a physiological event in the normal functioning immune system. Furthermore T and B cells recognizing self antigens can be easily cloned from healthy individuals and sometimes be shown to confer autoimmune disease by passive transfer in the experimental situation. The issue is how potentially autoaggressive cells can become activated and how such activity can be contained safely. Experimentally, autoimmune disease can be evoked by immunization with autoantigens (encephalomyelitis, thyroiditis etc.) or with foreign antigens that feature antigenic relationships with self antigens (adjuvant arthritis). In both situations transfer of disease has been shown with cloned T cells of a single specificity. In addition, specific control of disease using the same cloned T cells has been achieved. Adjuvant arthritis has been illustrative in these respects. By means of specificity analysis of cloned T cells, a 65 kD heat shock protein of mycobacteria was identified as crucial in the disease. Immunization with this antigen has been found to prevent the development of disease, including forms elicited without mycobacterial involvement. Furthermore, vigorous immunological responses to HSP65 were found both in experimental animals and also in humans as a consequence of exposition to various infectious organisms. By their conserved nature HSPs have ample potential for dangerous mimicry. Recent evidence accumulated suggesting that the same HPS65 may be crucial in human chronic arthritis as well. Therefore it is hoped that extrapolation of the experimental findings to the human situation will help the development of specific means, either T cells or antigens, to control spontaneous autoimmune arthritis in man.  相似文献   
13.
A phase II study of ifosfamide in children with recurrent solid tumours   总被引:3,自引:0,他引:3  
Summary Twenty children with recurrent or unresponsive tumours (10 Wilms', 3 rhabdomyosarcoma, 4 Ewings's, 1 osteosarcoma, 1 hepatoblastoma, 1 hepatoma) and one untreated patient with renal carcinoma were given ifosfamide as a 24-h infusion (5 mg/m2), with mesna as uroprotective. The number of courses ranged from 1 to 13 (median 3), and the interval between them was 2–3 weeks. Sixteen of these patients had previously received cyclophosphamide. Complete clinical responses were seen in 3 cases (2 Wilms' and 1 Ewing's) and lasted 5, 7, and 9 months. Partial responses were seen in 3 instances, mixed response or stable disease in 4, and progressive disease in 11. Treatment was well tolerated in most patients, with no cystitis or severe myelosuppression, but 2 children developed transient neurological symptoms and 1 became hypertensive. Nausea and vomiting were controlled by high-dose dexamethasone in most children.Plasma ifosfamide levels were estimated by means of gas-liquid chromatography in 10 patients. Peak concentrations ranged from 38 to 125 g/ml (median 80). The elimination half-life, at 2.5–5.2 h (median 3.2) was shorter than previously reported in adults.Future studies should test the possibility that ifosfamide-containing combination chemotherapy may be more effective than the regimens, usually including cyclophosphamide, that are currently used as front-line treatment of embryonal and Ewing's sarcoma.  相似文献   
14.
The aim of this paper is twofold. Firstly, to investigate the potential benefits of online health communities (OHCs) for informal caregivers by conducting a systematic literature review. Secondly, to identify the relationship between the potential benefits of OHCs and resilience factors of older adults. Performing a thematic analysis, we identified the potential benefits of OHCs for informal caregivers of older adults, including two salient themes: (a) caregivers sharing and receiving social support and (b) self and moral empowerment of caregivers. Then, we uncovered how these potential benefits can support resilience of older adults. Our findings show that sharing and receiving of social support by informal caregivers, and self and moral empowerment of informal caregivers in OHCs, can support four resilience factors among older adults, including self-care, independence, altruism and external connections. This review enables a better understanding of OHCs and Gerontology, and our outcomes also challenge the way healthcare and aged-care service providers view caregivers and older adults. Furthermore, the identified gap and opportunities would provide avenues for further research in OHCs.  相似文献   
15.
Electron microscopy has been the ‘gold standard’ of spatial resolution for studying the structure of the cell nucleus. Electron spectroscopic imaging (ESI) offers advantages over conventional transmission electron microscopy by eliminating the need for heavy-atom contrast agents. ESI also provides mass-dependent and element-specific information at high resolution, permitting the distinguishing of structures that are primarily composed of protein, DNA, or RNA. The technique can be applied to understand the structural consequences of epigenetic modifications, such as modified histones, on chromatin fiber morphology. ESI can also be applied to elucidate the multifunctional behavior of subnuclear ‘organelles’ such as the nucleolus and promyelocytic leukemia nuclear bodies. The authors dedicate this paper to the memory of Ying Ren (1961–2007). We all benefited from knowing her. Our research advanced through the technical creativity she provided.  相似文献   
16.
During 1996 and 1997 a panel of European haematologists, oncologists, and neonatologists developed specific paediatric guidelines for the use of colony stimulating factors based on published literature and the clinical experience of these specialists within each of 13 countries. Well established indications for use comprise intervention in patients with life-threatening infection, adjunctive therapy post autologous bone marrow transplantation (BMT), mobilization of peripheral blood progenitor cells for autologous BMT, patients with acquired aplastic anaemia on anti-lymphocyte globulin and cyclosporin regimen, and severe congenital neutropenia. Less clear indications include primary prophylaxis to support dose intensification in children with high risk/advanced malignancies, secondary prophylaxis to prevent neutropenia in patients with a history of severe neutropenia, support therapy in cases of poor marrow function following BMT and for deteriorating marrow function following successful BMT, in neonatal sepsis and non infectious neonatal neutropenia, in drug induced neutropenia and in HIV-positive patients. Treatment is generally well tolerated and granulocyte colony stimulating factor appears better tolerated than granulocyte and macrophage colony stimulating factor. Economically colony stimulating factors have not been shown to induce excessive costs for a given patient. Conclusion In general the adult guidelines are applicable to children but additional considerations (aggressive or very progressive childhood neoplasms, specific indications, neonatal use, congenital disorders) must be taken into account. Received: 21 October 1997 and in revised form: 30 April 1998 /Accepted: 5 May 1998  相似文献   
17.
OBJECTIVE: To evaluate the joint impact of pregnancy risk and the timing of referral of high-risk pregnancies from obstetricians to maternal fetal medicine (MFM) sub-specialists on gestational age (GA) at delivery. METHODS: For the period 1992-2002, 2567 consecutive deliveries from pregnancies of at least 23 weeks gestational age (GA) from a community-level sub-specialty perinatal center were studied. A multiple regression model was developed specifying the impact of various risk factors and referral timing. RESULTS: Prior pregnancy risk was inversely related to GA at birth. Referral timing, operationalized as a continuous variable, did not have a significant additive impact on GA at birth, but several dummy-variable interaction effects combining risk factors and referral before 20 weeks as a dichotomy were significant. CONCLUSION: There are identifiable risks that occur either before the pregnancy or early into it that should lead to early referral to a sub-specialist because of their impact on GA at birth. Early referral is an important tactic in a larger preterm prevention strategy, but it needs to be embedded in a broader maternal-fetal health initiative in which both generalists and sub-specialists play important roles.  相似文献   
18.
OBJECTIVE: To evaluate menopausal symptoms and quality of life in middle-aged women. STUDY DESIGN: Hospital-based, cross-sectional study. METHODS: A survey was conducted among 270 women aged 45-65 years who attended the gynecological and menopause clinic, Songklanagarind Hospital. We used the MENQOL questionnaire as the instrument. RESULTS: The average age at menopause of the postmenopausal women was 48.7 years (range 40-57 years). The prevalences of the classical menopausal symptoms--hot flushes, night sweats, and vaginal dryness--in the women aged 45-65 years were 36.8%, 20.8 and 55.3%, respectively. The three most prevalent symptoms in perimenopause were aching in muscles and joints, experiencing poor memory, and change in sexual desire. Within the four domains (vasomotor, psychological, physical, and sexual symptoms), more suffering was reported in the perimenopausal and postmenopausal subjects than in the premenopausal subjects (p < 0.001). CONCLUSIONS: Peri- and postmenopausal women had a significant decrease in quality of life compared to premenopausal women.  相似文献   
19.
The United Kingdom Childhood Cancer Study, a population-based case-control study covering the whole of Great Britain, incorporated a pilot study measuring electric fields. Measurements were made in the homes of 473 children who were diagnosed with a malignant neoplasm between 1992 and 1996 and who were aged 0-14 at diagnosis, together with 453 controls matched on age, sex and geographical location. Exposure assessments comprised resultant spot measurements in the child's bedroom and the family living-room. Temporal stability of bedroom fields was investigated through continuous logging of the 48-h vertical component at the child's bedside supported by repeat spot measurements. The principal exposure metric used was the mean of the pillow and bed centre measurements. For the 273 cases and 276 controls with fully validated measures, comparing those with a measured electric field exposure >/=20 V m(-1) to those in a reference category of exposure <10 V m(-1), odds ratios of 1.31 (95% confidence interval 0.68-2.54) for acute lymphoblastic leukaemia, 1.32 (95% confidence interval 0.73-2.39) for total leukaemia, 2.12 (95% confidence interval 0.78-5.78) for central nervous system cancers and 1.26 (95% confidence interval 0.77-2.07) for all malignancies were obtained. When considering the 426 cases and 419 controls with no invalid measures, the corresponding odds ratios were 0.86 (95% confidence interval 0.49-1.51) for acute lymphoblastic leukaemia, 0.93 (95% confidence interval 0.56-1.54) for total leukaemia, 1.43 (95% confidence interval 0.68-3.02) for central nervous system cancers and 0.90 (95% confidence interval 0.59-1.35) for all malignancies. With exposure modelled as a continuous variable, odds ratios for an increase in the principal metric of 10 V m(-1) were close to unity for all disease categories, never differing significantly from one.  相似文献   
20.
AIMS: To examine the experience of menopause in Indian women (aged 45-65 years) in Sydney, and the relationship between sociodemographic factors and menopausal symptoms, and also to explore the cultural context. METHODS: Two hundred and three women were interviewed about their menopausal experiences in the preceding week using the 29-item Menopause-Specific Quality of Life questionnaire. RESULTS: The mean age of menopause for Indian women was found to be earlier than in other groups in the published literature, at 48.21 years. While there were higher scores for physical symptoms than for other symptoms, and there were significant differences between perimenopausal women and the others, it was found that the prevalence of classical menopausal symptoms was lower in Indian women than that found in Caucasians. However, physical and several psychological symptoms were found to be more prevalent than the usual vasomotor symptoms. Unemployed women and women with a tertiary level of education were found to experience a significantly higher score for all symptoms in our sample. CONCLUSIONS: Lower scores of menopause symptoms indicate that Indian women have fewer complaints of symptoms and a positive attitude towards menopause. Somatic symptoms are multifactorial in nature and could be because of health problems associated with ageing, midlife crises and cultural influences. Further detailed studies could examine the important relationship between cultural lifestyle factors and climacteric symptoms.  相似文献   
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