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81.
The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher.  相似文献   
82.
Lewis Histo-Blood Group System and Associated Secretory Phenotypes   总被引:6,自引:0,他引:6  
This review summarises present knowledge of the chemistry, immunology, genetics and clinical significance of antibodies in the Lewis and secretor histoblood group systems. Although red cell serology has laid the foundations for these systems, more recent advances have been made by studying Lewis and related glycoconjugates with monoclonal antibodies, determining structures by mass spectrometry and NMR spectroscopy, identifying enzymes and their specificities, and identifying the genes by molecular biology. The expression of Lewis system antigens is dependent on Lewis and secretor loci. Fucosyltransferases coded by genes at these loci compete and interact with each other and with other transferases to determine an individual's Lewis and secretor phenotype. Exocrine epithelial cells, mostly of endodermal origin, synthesise the Lewis antigens which, as plasma glycolipids, are secondarily acquired by cells of the peripheral circulation. Phenotyping red cells is often regarded as a simple way of determining the Lewis and sometimes the secretor status of an individual; however, the red cell phenotype is influenced by many factors and may not necessarily reflect someone's Lewis and secretor genotypes. Two main red cell Lewis groups are usually found, Lewis negative and Lewis positive. In Lewis-negative individuals, the secretor genotype does not affect the Lewis phenotype, but in Lewis-positive individuals, the non-secretor genotype generates the Le(a+b–) phenotype, the secretor genotype causes the Le(a–b+) phenotype, and the partial secretor genotype gives rise to the Le(a+b+) phenotype.  相似文献   
83.
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
84.
85.
In order to determine whether a specialist psychogeriatric nursing home was fulfilling its intended role of caring for the most behaviourally disturbed dementia sufferers, 24 of its demented residents were compared with 28 demented individuals discharged from a psychiatric unit to ordinary nursing homes and 30 mobile dementia sufferers in nursing home wards of a geriatric centre. Those in the psychogeriatric nursing home showed more disturbed behaviours than those in the other two settings. Scores on the Rating Scale for Aggressive Behaviour in the Elderly were compared with degree of cognitive impairment for the first time in the literature and showed no correlation with degree of cognitive impairment for the first time in the literature and showed no correlation with congnitive performance.  相似文献   
86.
Background: A quantitative scale of intubation difficulty would be useful for objectively comparing the complexity of endotracheal intubations. The authors have developed a quantitative score that can be used to evaluate intubating conditions and techniques with the aim of determining the relative values predictive factors of intubation difficulty and of the techniques used to decrease such difficulties.

Methods: An Intubation Difficulty Scale (IDS) was developed, based on parameters known to be associated with difficult intubation. It was then evaluated prospectively in a group of 311 consecutive prehospital intubations and 315 intubations in an operating room. In the operating room, the IDS was compared with two other parameters: the time to completion of intubation and the visual analog scale (VAS). Time was measured by an independent observer. Operators in both groups completed a checklist regarding the conditions of intubation.

Results: There is a good correlation between the IDS scale and the VAS assessment of difficulty and time to completion of intubation. VAS and time to completion have a significant but lesser correlation to each other. Comparison of IDS with operator-assessed subjective categorical impression of difficulty by Kruskall-Wallis was statistically significant.  相似文献   

87.
Background : A retrospective analysis of 103 case records from 1978 to 1996 with a provisional diagnosis of Buerger's disease was undertaken at the Department of Surgery, University of Hong Kong, Queen Mary Hospital. The aim of the study was to elucidate the clinical course and evaluate the results of surgical intervention of Buerger's disease in Hong Kong Chinese people. Methods : Fourteen patients were subsequently excluded from the study because of inability to fulfil our diagnostic criteria. Data on clinical presentation, investigations, indications and results of surgical intervention were reviewed. Sympathectomies and arterial reconstructions were performed on 42 and four patients, respectively, for critical ischaemia or rest pain. Outcome was analysed with respect to the rate of ulcer healing, pattern of recurrence and limb loss. Results : The patients were all young male heavy smokers with a mean age of 36.5 years. The majority of patients (80%) presented with ischaemic ulceration or gangrene. Vascular reconstruction was undertaken in four patients and satisfactory long-term results were obtained in three patients. Sympathectomy was able to relieve symptoms in 87% of operated patients and ischaemic ulceration healed in 2.6 (mean) ± 1.7 (SD) months after the operation. If the patient continued to smoke, surgical intervention did not exempt the patient from a relapse or amputation. Conclusion : Sympathectomy provides short-term pain relief and promotes ulcer healing in patients with Buerger's disease but carries no long-term benefit. Complete abstinence from smoking is the only means of arresting the progression of the disease.  相似文献   
88.
Our previous studies have shown that the in vitro assay of donor antigen-specific hyporeactivity is a useful marker for identifying solid organ transplant recipients (kidney, lung and heart) at low risk for immunologic complications (i.e., late acute rejection episodes and chronic rejection). Donor antigen-specific hyporeactivity is defined as a significantly decreased post- vs. pretransplant proliferative response to donor antigens while response to third-party controls remains unchanged. We analyzed whether exposure to the same HLA-DR antigen pretransplant via random blood transfusion and posttransplant via the transplanted organ influenced the development of hyporeactivity. Thirty previously nontransfused recipients, each receiving two 150 ml pretransplant random blood transfusions, were assessed for hyporeactivity at 1 year posttransplant. Of the 12 recipients with pretransplant exposure to kidney HLA-DR via transfusions, 6 (50%) developed hyporesponsiveness; in contrast, of the 18 recipients who were not preexposed, only 3 (15%) exhibited this form of immunomodulation. Of interest, 2 of the 3 hyporesponsive recipients who were not preexposed, received units containing HLA-DR antigens previously shown to share crossreactive epitopes with the kidney HLA-DR. In conclusion, these results suggest a increased incidence in the development of hyporeactivity in patients receiving pretransplant transfusions which share an HLA-DR antigen with the transplanted kidney.  相似文献   
89.
90.
SUMMARY: This report concerning the immunization of adolescents (ie, persons 11–21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (ie, MMWR 1994;43[No. RR-1] 1–38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians [AAFP]; and AMA Guidelines for Adolescent Preventive Services [GAPS]: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11–12 years of age by establishing a routine visit to their health-care providers. Specifically, the purposes of this visit are to a) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps, and rubella (MMR) vaccine; b) provide a booster dose of tetanus and diphtheria toxoids; c) administer other vaccines that may be recommended for certain adolescents; and d) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine. The most recent recommendations from AC1P, AAP, AAFP, and AMA concerning specific vaccines and delivery of preventive services should be consulted for details.  相似文献   
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