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21.
The possibility of separating the impurities of mildronate, an antiischemic drug, by hydrophilic interaction chromatography (HILIC) was investigated on different polar stationary phases (silica, amino, cyano and zwitterionic sulfobetaine). The investigations have shown that HILIC is a useful alternative to reversed phase and ion-pair chromatography. The impact of HILIC separation conditions (acetonitrile content, buffer pH in mobile phase) on retention and selectivity has been systematically studied. Importance of these factors was found to be dependent on the structural properties of solutes. A HILIC method using a zwitterionic sulfobetaine stationary phase was developed and validated to determine six impurities in the drug substance. The method was validated in terms of specificity, limit of quantitation, limit of detection, linearity, accuracy and precision.  相似文献   
22.
PurposeRadiation therapy for mesothelioma remains challenging, as normal tissue toxicity limits the amount of radiation that can be safely delivered to the pleural surfaces, especially radiation dose to the contralateral lung. The physical properties of proton therapy result in better sparing of normal tissues when treating the pleura, both in the postpneumonectomy setting and the lung-intact setting. Compared with photon radiation, there are dramatic reductions in dose to the contralateral lung, heart, liver, kidneys, and stomach. However, the tissue heterogeneity in the thorax, organ motion, and potential for changing anatomy during the treatment course all present challenges to optimal irradiation with protons.MethodsThe clinical data underlying proton therapy in mesothelioma are reviewed here, including indications, advantages, and limitations.ResultsThe Particle Therapy Cooperative Group Thoracic Subcommittee task group provides specific guidelines for the use of proton therapy for mesothelioma.ConclusionsThis consensus report can be used to guide clinical practice, insurance approval, and future research.  相似文献   
23.
Dower J  Donald M  Begum N  Vlack S  Ozolins I 《Vaccine》2011,29(16):3031-3037
Using findings from a random, computer assisted telephone survey of households, this paper examines influenza and pneumococcal immunisation coverage and predictors of immunisation in 2203 adults with asthma, diabetes or a cardiovascular condition living in Queensland, Australia. 47% and 31% of high-risk persons were immunised against influenza and pnemococcus respectively. Immunisation coverage varied across chronic conditions and increased with age, being significantly higher for those aged 65 years and older and consequently eligible for free vaccination. Poor self reported health status was an independent predictor of pneumococcal vaccination status for people with asthma, diabetes or a cardiovascular condition; however it was only an independent predictor of influenza immunisation status for people with diabetes. Extending free vaccination to all people at risk may increase immunisation rates for younger people with a chronic condition  相似文献   
24.
Clarification of the mechanisms of hydrogen release and uptake in transition-metal-doped sodium alanate, NaAlH(4), a prototypical high-density complex hydride, has fundamental importance for the development of improved hydrogen-storage materials. In this and most other modern hydrogen-storage materials, H(2) release and uptake are accompanied by long-range diffusion of metal species. Using first-principles density-functional theory calculations, we have determined that the activation energy for Al mass transport via AlH(3) vacancies is Q = 85 kJ/mol.H(2), which is in excellent agreement with experimentally measured activation energies in Ti-catalyzed NaAlH(4). The activation energy for an alternate decomposition mechanism via NaH vacancies is found to be significantly higher: Q = 112 kJ/mol.H(2). Our results suggest that bulk diffusion of Al species is the rate-limiting step in the dehydrogenation of Ti-doped samples of NaAlH(4) and that the much higher activation energies measured for uncatalyzed samples are controlled by other processes, such as breaking up of AlH(4)(-) complexes, formation/dissociation of H(2) molecules, and/or nucleation of the product phases.  相似文献   
25.
26.

Background  

For management of thyroid nodules, distinction between benign and malignant tumours is essential. The study was performed to evaluate the diagnostic value of molecular markers in different thyroid tumours.  相似文献   
27.
Background There is an urgent need for the recognition of sexually transmitted infections (STIs) as a serious public health problem in Europe. The lack of standardization in testing, along with poor reporting and surveillance mechanisms, have resulted in low reported rates of STIs in many European Union (EU) countries, reinforcing the erroneous assumption that STIs are not a major problem. Testing and diagnosis of STIs must therefore be improved and enhanced. Recommendations Reporting of Chlamydia trachomatis infection, gonorrhoea and syphilis should be mandatory, and an integrated surveillance system for C. trachomatis implemented in all European countries. Implementation of the European Centre for Disease Prevention and Control (ECDC) surveillance mechanisms for STIs in all EU countries is highly recommended. A necessary component for successful introduction of the HPV vaccine, as with any vaccination programme is a well‐planned and organized information campaign.  相似文献   
28.
It is unclear whether the maturation of corticotrophs from the fetal to the adult type in the fetal sheep pituitary in late gestation is associated with changes in the sensitivity of the fetal pituitary to corticotrophic secretagogues and in the form of ACTH-containing peptides (IR-ACTH) secreted into the circulation. The maturation of the pituitary corticotroph population is known to be accelerated by intrafetal cortisol infusion and delayed by bilateral fetal adrenalectomy. We have therefore investigated the mol wt profile of IR-ACTH present in fetal sheep plasma from 110 days gestation until term (147 +/- 3 days) and determined whether intrafetal cortisol infusion between 105-117 days (2.5 mg cortisol/day), or bilateral fetal adrenalectomy can alter the mol wt profile of IR-ACTH in fetal sheep plasma. We have also investigated whether prior exposure to cortisol alters the subsequent responsiveness of the fetal pituitary to a long term infusion of ovine (o) CRF (10 micrograms oCRF/day). In the control group, the proportion of IR-ACTH which eluted in the low-mol wt (LMW) range (i.e. less than 12K) was significantly higher between 121-125 days (43.9 +/- 4.2%) than between 126-139 days (26.8 +/- 9.3%) but not different to that after 140 days gestation (29.9 +/- 5.5%). Between 110-117 days, cortisol infusion had no effect on the proportion of IR-ACTH in the LMW range (43.9 +/- 5.7%, saline infused; 44.1 +/- 2.4%, cortisol infused). Between 121-125 days, the proportion of IR-ACTH in the LMW range in the CRF-infused groups (with or without prior exposure to cortisol) was significantly lower (27.4 +/- 2.1%) than in the saline-infused control group. In contrast, after fetal adrenalectomy, the proportion of IR-ACTH in the LMW range between 126-139 days was significantly higher (48.0 +/- 6.7%) than in intact control animals (23.8 +/- 3.5%). We conclude that the change in the mol wt profile of IR-ACTH in fetal plasma after 125 days may be a consequence of changes in the morphological and/or functional characteristics of the corticotrophic cells in the fetal pituitary. Infusion of oCRF appears to accelerate the normal maturation of the fetal pituitary-adrenal relationship, and oCRF acting either directly or via secretion of cortisol may play a role in the posttranslational processing of POMC in the fetal sheep pituitary after 125 days gestation.  相似文献   
29.
Summary The development and transformation of the aortic arches were studied in 84 equine embryos (5 to 35 mm CRL; approximately 21–49 days of gestation). The arch of the aorta and the vessels which originate from it were also examined in several fetuses (41–335 mm CRL) and in a full-term fetus.There are six pairs of aortic arches that originate from the ventral aortic root. The first and second aortic arches regress very early, while the fifth pair appears in a vestigial form relatively late in the development, when the truncus arteriosus divides into the aortic and pulmonary channels. The development of the cervical intersegmental arteries is described and the formation of the subclavian arteries is discussed. The primitive arch of the aorta appears at the earliest in the 14–15.5 mm CRL equine embryos (approximately 35 days of gestation). The segments of the aortic arches system which are incorporated in the formation of the definitive arch of the aorta are discussed.Three vessels, the innominate (brachiocephalic) artery, the left common carotid artery, and the left subclavian artery, originate from the primitive arch of the aorta. This arrangement of the vessels is regarded as the primitive mammalian pattern.Two more stages precede the development of the definitive arch of the aorta and the common brachiocephalic trunk in the equine embryos, at approximately 42 days of gestation. The secondary changes, which occur in the process of formation of the arch of the aorta and the common brachiocephalic trunk, are described and discussed. Certain anomalies of the arrangement of the vessels from the arch of the aorta are also discussed. In memoriam of Professor Dr. L. Kundzin (1855–1940).The investigation reported herein was supported by a Research Grant-in-Aid from the Washington State University.  相似文献   
30.

Objective

This study explores a range of relevant socio-demographic, physical and psychological factors in a unique examination of the risk factors for frequent attendance at primary care. The impact of patient activation for self-management on health service utilisation is of particular interest.

Methods

A population-based sample of people with chronic disease from Queensland, Australia, was interviewed using computer assisted telephone surveying. Data were collected from a random sample of 1470 people with either diabetes or a cardiovascular condition.

Results

As participants became more activated they were less likely to frequently attend their main health care provider for assistance with their chronic condition. For both conditions the association was graduated and for participants with a cardiovascular condition this association remained statistically significant even after controlling for other potentially influential factors such as disease severity, length of time since diagnosis, and psychological distress.

Conclusion

Characteristics of the individual, including patient activation and psychological functioning, as well as disease factors contribute to primary care consulting patterns among people with chronic illness.

Practical implications

Efforts to improve patient activation for self-management should remain a central element of chronic care.  相似文献   
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