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1.
The “delayed infection hypothesis” states that a paucity of infections in early childhood may lead to higher risks of childhood leukemia (CL), especially acute lymphoblastic leukemia (ALL). Using prospectively collected data from six population-based birth cohorts we studied the association between birth order (a proxy for pathogen exposure) and CL. We explored whether other birth or parental characteristics modify this association. With 2.2 × 106 person-years of follow-up, 185 CL and 136 ALL cases were ascertained. In Cox proportional hazards models, increasing birth order (continuous) was inversely associated with CL and ALL; hazard ratios (HR) = 0.88, 95% confidence interval (CI): (0.77–0.99) and 0.85: (0.73–0.99), respectively. Being later-born was associated with similarly reduced hazards of CL and ALL compared to being first-born; HRs = 0.78: 95% CI: 0.58–1.05 and 0.73: 0.52–1.03, respectively. Successive birth orders were associated with decreased CL and ALL risks (P for trend 0.047 and 0.055, respectively). Multivariable adjustment somewhat attenuated the associations. We found statistically significant and borderline interactions between birth weight (p = 0.024) and paternal age (p = 0.067), respectively, in associations between being later-born and CL, with the lowest risk observed for children born at <3 kg with fathers aged 35+ (HR = 0.18, 95% CI: 0.06–0.50). Our study strengthens the theory that increasing birth order confers protection against CL and ALL risks, but suggests that this association may be modified among subsets of children with different characteristics, notably advanced paternal age and lower birth weight. It is unclear whether these findings can be explained solely by infectious exposures.  相似文献   
2.
Over the last several decades, significant advances and improvements in care of transplant patients have resulted in markedly improved outcomes. A number of options are available for patients with advanced cardiopulmonary dysfunction requiring transplantation. There is a debate about when isolated heart or isolated lung transplantation is no longer possible or advisable and combined heart-lung transplantation is justified. Organ availability and allocation severely limit the latter option to very few well-selected patients. We review practice patterns, trends, and outcomes after triple-organ heart-lung transplant (HLTx) worldwide, as well as our own experience with heart-lung transplant in the modern era.  相似文献   
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Rats were fed a low calcium diet deficient in vitamin D for 14 days. Changes in alkaline phosphatase activities in odontoblasts dissected out from incisor teeth were studied biochemically. A strong increase in pNPP-ase, PPi-ase, total ATP-degradation and Ca2+- ATPase was observed in the deficient animals compared with animals fed a control diet.  相似文献   
5.
The effect of antibacterial treatment on the prevalence of gram-negative rods (enterobacteria and Pseudomonas) in the mouths of patients with leukemia was studied. Of the patients' salivary samples, 45% contained gram-negative rods compared with 12% in a control group of healthy persons. The antibacterial resistance patterns of gram-negative rods from healthy persons were different from those of the hospitalized patients. No relationship was found between the amount of antibacterial treatment and presence of gram-negative rods. The gram-negative rods recovered from individual patients were usually not resistant to the antibacterial agents given to the patients in question. Only a few patients harbored the same clone of a gram-negative rod for a lengthy period. The resistance patterns of these clones of gram-negative rods were similar to those of gram-negative rods that were transient in the mouth. It was concluded that resistance to antibacterial agents is not a factor of major importance for the capacity of the gram-negative rods to become established in the mouths of hospitalized patients with leukemia.  相似文献   
6.

Background

Treatment of acetabular bone loss with impaction bone grafting (IBG) at revision total hip arthroplasty is highly dependent on mechanical stability and graft compression for clinical success. Here, we describe a new technique to further compress and stabilize the acetabular graft bed with a thin, perforated titanium shell.

Methods

We retrospectively analyzed 170 cases of acetabular revision arthroplasty 7 years (standard deviation 2.8) after IBG combined with a graft-compressing titanium shell implant. The patients were reviewed by clinical score and radiography. Three patients were lost to follow-up. The medical journals of the 33 deceased cases were reviewed for any reoperation. Of the 170 cases, 74 had a cavitary acetabular bone defect, 93 had combined segmental and cavitary bone defects, and 3 had a pelvic dissociation. Bone graft incorporation was assessed and correction of the hip center of rotation was calculated.

Results

Five cases (3%) were reoperated for mechanical loosening. One more was assessed as loose but asymptomatic and was not planned for revision. There were 3 reoperations for recurrent dislocation, 2 for deep infection and 1 for technical error. Reoperation for any reason, as the end point of survivorship, showed a survival rate of 92% after 10 years. Hip score according to Merle, d'Aubigne, and Postel increased from 10.8 (preoperatively) to 16.4 at follow-up. The clinical and radiological results were excellent.

Conclusion

IBG combined with the compressing shell results in excellent results for this challenging condition.  相似文献   
7.
This study focused on the great shortage of registered nurses (RNs) in primary health care in Rajasthan, India. It dealt especially with the nurses' own opinions about working in primary health care and their reasons for not working in it. Nurses at different levels in the health care organization were interviewed. The study was based on interviews with six RNs individually, three groups of six to eight nursing students each, and three policy-making chief nurses individually. The Minister of Health in Rajasthan also participated in the study. The study showed that the reasons for the lack of RNs in community health care were as follows: a government policy decision to place less educated nurses in the communities; the great shortage of nurses in general; the system whereby a nurse is not able to choose her/his place of work; unwillingness on the part of the nurses to work in community health care because of the great security problems; lack of support from authorities and lack of equipment. In general, community health care nursing as a work area was despised by society at large in Rajasthan.  相似文献   
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The present literature review is focused on two main areas: (i) periodontal conditions in older individuals; and (ii) the scientific data available on periodontal treatment outcomes in individuals ≥ 75 years of age. The population of older people is increasing but the data on periodontal therapies and their efficacy in this population are limited and need to be carefully reviewed. Although life expectancy has increased, this does not mean that older people are medically healthy. Several chronic systemic diseases are associated with periodontitis, and the prevalence of most chronic diseases increases with age. Furthermore, older people are challenged by impaired immunity (immune senescence) with a decline in the numbers of naïve T‐cells in peripheral blood and lymphoid tissues. The most frequent significant correlates with successful ageing include not smoking and the absence of disability, arthritis and diabetes mellitus. Periodontal diseases in older individuals may have specific features that are not consistent with periodontal diseases. In this respect, data suggest that gingival lesions in older individuals develop differently from gingival lesions in younger adults. The progression of periodontitis may be slower in older individuals, and older individuals with periodontitis may benefit from more conservative treatment approaches. Diagnostic criteria used for the assessment and diagnosis of periodontitis in younger adults may not be fully applicable in older individuals. In summary, declining health, perception of treatment needs, dietary changes, comorbidity with other diseases and immune senescence are challenging factors to clinicians and researchers, in terms of therapies and in understanding periodontitis etiology in older individuals.  相似文献   
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