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101.
The ciliated epithelium of the respiratory airways is one of the first vital systemic surfaces in contact with the ambient air. Ex vivo nasal epithelial ciliary beat frequency (CBF) at room temperature is on the order of 7–8 Hz but may be stimulated by irritant exposure. The upregulation of CBF in response to acute irritant exposure is generally considered to be a transient event with eventual return to baseline. However, studies of CBF dynamics in response to typical lifestyle exposures are limited. This study assessed nasal epithelial CBF among human subjects as a function of quantifiable lifestyle tobacco smoke exposure. Nasal epithelial biopsies were obtained from human subjects with well documented histories of tobacco smoke exposure. CBF was determined using a digital photometric technique and concurrent assays of nasal nitric oxide and urine cotinine and creatinine were performed. Mean CBF among active smokers and non-smokers exposed to environmental tobacco smoke (ETS) was elevated over non-smokers. Although there were dramatic differences in relative levels of tobacco smoke exposure, CBF values among tobacco smoke-exposed groups were comparable. Parallel in vitro studies of cultured nasal epithelium exposed to cigarette smoke condensate further supported these observations. These studies suggest that persistent elevation in nasal epithelial CBF is an early, subtle, physiologic effect associated with lifestyle tobacco smoke exposure. The molecular mechanisms that upregulate CBF may also create a cell molecular milieu capable of provoking the eventual emergence of more overt adverse health effects and the pathogenesis of chronic airway disease.  相似文献   
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Infective (bacterial) endocarditis has presented a "changing face" over the previous years but remains a disease with potentially serious complications. Surveys have indicated that up to 92% of cases of infective endocarditis could be attributed to a dental origin; yet most susceptible persons do not understand their condition or the precautions necessary prior to dental treatment. Up to 80% of infective endocarditis patients received no protection prior to dental or genitourinary manipulation. Dental practitioners, therefore, play an important role in the prevention of this disease and must be familiar with recent developments on the subject. This article provides an in-depth review of the disease and outlines and stresses the dental practitioner's responsibility in its prevention.  相似文献   
104.
BackgroundPrimary vaginal stones in children are extremely rare and removal can be difficult. We describe a procedure for safe extraction of vaginal stones.CaseA 5-year-old, wheelchair-bound girl was referred to the urologic department with recurrent febrile urinary tract infection. Diagnostics of the kidneys showed no abnormalities. The bladder appeared to contain two stones. On urethro-cystoscopy no stones were seen. Vaginoscopy identified vaginal stones. After 4 weeks of estrogen treatment, a second procedure via vaginal introduction of a nephroscope in combination with an ultrasonic device, effectively disintegrated the stones.Summary and ConclusionWe recommend the use of a nephroscope in visualizing the vagina and cervix and facilitating instrumentation in prepubertal girls.  相似文献   
105.

Background

People with dementia can benefit from a palliative care approach. Recommendations, such as those of the EAPC have been proposed to strengthen the provision of palliative care for this group of patients. Yet, it remains challenging for professionals to identify when a person with dementia is in need of palliative care. The objective of this study therefore was to explore when professionals in long-term care settings consider a person with dementia in need of palliative care.

Methods

Teams with in total 84 professionals working in 13 long-term care settings from 6 countries (France, Germany, Italy, Norway, Poland and the Netherlands) received a case-vignette concerning a person with dementia recently admitted to a nursing home. Teams were asked to discuss when they considered people with dementia eligible for palliative care. The constant comparative method was used to analyse their answers.

Results

Three different time points in the disease trajectory when people with dementia were considered to be eligible for palliative care were extracted: (1) early in the disease trajectory; (2) when signs and symptoms of advanced dementia are present; and (3) from the time point that curative treatment of co-morbidities is futile. Yet, none of these time points was uniformly considered by the professional teams across Europe. In some cases, professionals working in the same nursing home didn’t even reach consensus when considering persons with dementia eligible for palliative care.

Conclusion

The results of the study identified that professionals across Europe have different opinions regarding the time point when to consider a person with dementia in need of palliative care.
  相似文献   
106.
Over the past decade, facial cosmetic procedures have become more commonplace in dentistry and oral and maxillofacial surgery. An increasing number of patients seek minimal invasive procedures. One of the most requested procedures is treatment with botulinum toxin type A (BoNTA). Treatment of dynamic rhytids and lines with BoNTA is effective and produces high rates of improvement with rapid onset and long duration of action (longer than 4 months for some patients) compared with placebo. This paper considers the history and pharmacology of this neurotoxin, and focusses on the literature concerning the treatment of different facial areas with BoNTA. It also presents clinical guidelines on the treatment of glabellar lines, the frontalis muscle, peri-orbital lines, gummy smile and masseter muscle hypertrophy. Knowledge about the mechanisms of action and the ability to use BoNTA as an adjunctive treatment are mandatory for those working in the field of cosmetic facial surgery.  相似文献   
107.
The gradual accumulation of chronic lymphocytic leukemia (B-CLL) cells is presumed to derive from proliferation centers in lymph nodes and bone marrow. To what extent these cells possess the purported antiapoptotic phenotype of peripheral B-CLL cells is unknown. Recently, we have described that, in B-CLL samples from peripheral blood, aberrant apoptosis gene expression was not limited to protective changes but also included increased levels of proapoptotic BH3-only member Noxa. Here, we compare apoptosis gene profiles from peripheral blood B-CLL (n=15) with lymph node B-CLL (>90% CD5+/CD19+/CD23+ lymphocytes with Ki67+ centers; n=9). Apart from expected differences in Survivin and Bcl-xL, a prominent distinction with peripheral B-CLL cells was the decreased averaged level of Noxa in lymph nodes. Mcl-1 protein expression showed a reverse trend. Noxa expression could be reduced also in vitro by CD40 stimulation of peripheral blood B-CLL. Direct manipulation of Noxa protein levels was achieved by proteasome inhibition in B-CLL and via RNAi in model cell lines. In each instance, cell viability was directly linked with Noxa levels. These data indicate that suppression of Noxa in the lymph node environment contributes to the persistence of B-CLL at these sites and suggest that therapeutic targeting of Noxa might be beneficial.  相似文献   
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109.
OBJECTIVE: The influence of ketoconazole on the various enzymes of human adrenal steroid biosynthesis was examined in vitro. MEASUREMENTS: After incubation of human adrenal tissue slices with labelled precursors and ketoconazole (0-2000 microM), radioactive metabolites were separated by thin-layer chromatography and quantified by liquid scintillation counting. Enzyme activity was assessed by measuring conversion of tritium-labelled precursors to products. RESULTS: In vitro, ketoconazole showed a significant inhibition on the following adrenal enzyme systems (with decreasing activity): C17,20-desmolase (IC50 2 microM), 16 alpha-hydroxylase (IC50 9 microM), 17 alpha-hydroxylase (IC50 18 microM), 18-hydroxylase (IC50 28 microM), and 11 beta-hydroxylase (IC50 35 microM). In the tested concentrations ketoconazole had no inhibitory effect on the 21-hydroxylase, the 3 beta-hydroxysteroid dehydrogenase and the 20-hydroxysteroid dehydrogenase component of the C17,20-desmolase enzyme system. CONCLUSIONS: The data are in accordance with clinical findings where a strong suppression of serum androgen levels by relatively selective inhibition of C17, 20-desmolase has been assumed. The predominant blocking effect of ketoconazole on adrenal as well as on gonadal androgen biosynthesis might be of clinical benefit in the management of hyperandrogenic states.  相似文献   
110.
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