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61.
K R Shah S Ng L Zeoli V Haight S Matz A F Kydonieus 《Journal of biomaterials applications》1986,1(2):239-273
The Hercon controlled drug delivery technology is based on a multi-layered laminated polymeric structure, in which a layer of vinyl chloride copolymer or terpolymer containing the drug is sandwiched between two or more layers of polymeric films. The drug is released from the device at a controlled rate by a process of diffusion through the reservoir and one of the outer layers, which can function as a rate controlling membrane. This basic technology has been successfully utilized for the development and commercialization of Nitroglycerin Transdermal System (NTS, Bolar Pharmaceutical Co., Inc). In vitro and in vivo investigations of transdermal delivery of different other drugs from the Hercon polymeric devices have indicated the feasibility of using this system to meet a variety of therapeutic needs. 相似文献
62.
Posterior rhinometric measurements of nasal resistance were conducted on two groups of patients with perennial rhinitis: those whose symptom of nasal stuffiness responded to a topical steroid spray and those in whom it did not. The anterior ends of the inferior turbinates in 48 patients were treated with either cryosurgery or cautery, and in half of the subjects the erectile tissue of the septum was also thermally ablated. Measurements were made before and 10-16 weeks after therapy. It is concluded from statistical comparison that there is no benefit to treating the septum, and that cryosurgery is more effective in those whose symptoms respond to topical steroids, while cautery works better in those who do not. Histology showed no change in the capacitance vessels (sinusoids) after either modality, and xylometazoline caused a marked decrease in nasal resistance, suggesting that vascular smooth muscle function was intact. Irrespective of the change in airway resistance, most subjects felt that there had been an improvement. The mechanism is discussed. 相似文献
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65.
IM Gardiner F Ahmed TJ Steiner A McBain C Kennard J de Belleroche 《Cephalalgia : an international journal of headache》1998,18(4):192-196
The project was an investigation into whether changes in the expression of G-proteins underlie altered cell signaling in migraine and cluster headache. The basis for this assumption is that altered physiological responses are seen in migraineurs and that differences in cell signaling are detected biochemically in various cell types isolated from peripheral blood. Levels of three G-protein mRNAs—Gsα, Giα, and Gqα were quantified in lymphocytes from clinically well-defined migraine and cluster headache patients and correlated with headache type and influence of drug treatment. Giα mRNA was reduced by 50% in all migraine patients compared with control subjects; similarly in patients with or without aura, in patients with a migraine headache at the time of sampling, and patients in a quiescent state. No reduction in the levels of Gsα or Gqα mRNA were seen in migraine patients. A smaller reduction was seen in cluster headache patients, most marked in those without medication. Levels of Gsα. mRNA were significantly reduced in cluster headache patients compared with migraine patients. The marked down-regulation of Giα mRNA in migraine, whether quiescent or acute, indicates either an adaptive response to headache in this group of patients or that low levels of Giα mRNA make individuals more susceptible to migraine. 相似文献
66.
BACKGROUND : Red cells (RBCs) stored in hypo-os-molar additive solutions with the same concentrations of adenine, dextrose, mannitol, and sodium chloride and varied amounts of ammonium, phosphate, glycerol, and glutamine were better preserved than RBCs in the standard additive solution (Adsol). Cell swelling occurred in all the experimental additives. This observation prompted the evaluation of glutamine and glycine alone, as well as a combination of glutamine and glycine, all of which have been described as producing swelling of rat liver cells. STUDY DESIGN AND METHODS : Aliquots of RBCs were stored at 4°C in Adsol or experimental additive solutions (EASs) all containing adenine, 2 mM; dextrose, 110 mM; mannitol, 55 mM; and sodium chloride, 50 mM. EAS 42 had, in addition, glutamine, 10 mM; glycine 5 mM; and phosphate, 20 mM. EAS 43 had glutamine, 10 mM; glycine, 10 mM; and phosphate 20 mM. EAS 44 had glutamine, 10 mM; EAS 45 had glutamine, 10 mM, and phosphate, 20 mM; and EAS 46 had only glycine, 10 mM. At intervals, measurements were made of mean corpuscular volume, mean corpuscular hemoglobin concentration, morphology, ATP, hemolysis, supernatant potassium, ammonia, pH, and microvesicles shed. RESULTS : The initial mean corpuscular volumes were larger in all EASs than in Adsol, but the greatest difference was between EASs 44 and 46 (108 fL) and Adsol (86 fL) (p<0.001). The morphology scores were significantly better in all the EASs (p<0.04). The ATPs were significantly greater in all the EASs (p<0.001), and highest in those with phosphate. Potassium leakage and hemolysis were less in the EASs (p<0.001). The ammonia levels were higher in all the EASs than in Adsol, with the exception of EAS 46. During storage, the extracorpuscular and intracorpuscular pH levels were essentially identical. The shedding of microvesicles was greatly reduced in all the EASs. CONCLUSION : Cell swelling induced in RBCs after collection appears to improve preservation. Ammonia and phosphate enhance RBC ATP maintenance. Glycine decreases the formation of ammonia by RBCs stored in a hypotonic medium. 相似文献
67.
Wei Qian James Haight Ian Poon Dan Enepekides Kevin M. Higgins 《Otolaryngology--head and neck surgery》2010,143(2):248-252
Objective
To determine the point prevalence of sleep apnea in patients following oral and oropharyngeal cancer treatment at a major tertiary care referral center.Study Design
A retrospective cross-sectional survey.Subjects and Methods
Twenty-four patients with established oral or oropharyngeal cancer were submitted to overnight polysomnography. The surgical group consisted of 15 patients (11 male, 4 female; average age 64.2 yrs) having undergone primary surgery with radial forearm free flap reconstruction. The remaining patients (5 male, 4 female; average age 54.8 yrs) were treated nonsurgically with chemoradiation therapy. The fatigue-related daytime sleepiness was measured with the Epworth sleepiness scale (ESS).Results
Eleven patients in the surgical group and three in the nonsurgical group had a respiratory disturbance index (RDI) greater than 15 (odds ratio = 5.5, P = 0.092). Twelve patients in the surgical group and five in the nonsurgical group had significant oxygen desaturation during sleep hours (odds ratio = 3.3, P = 0.356). There was no observed significant correlation between RDI and oxygen desaturation (r2 = 0.28), nor was there any observed association between the RDI and ESS score (r2 = 0.18).Conclusion
This preliminary study has suggested that surgical patients in our cohort have a higher prevalence of moderate to severe obstructive sleep apnea in the postoperative period, when tested, compared with a nonsurgical group. A small sample size and incomplete matching on important cofactors of interest, such as primary site location, body mass index, and thyroid function, limit this study. A pretreatment and post-treatment analysis is obviously required to demonstrate any significant level of association between treatment type and sleep apnea status. 相似文献68.
Ostler T Haight W Black J Choi GY Kingery L Sheridan K 《Journal of the American Academy of Child and Adolescent Psychiatry》2007,46(4):500-507
OBJECTIVE: This case-based, mixed-methods study was undertaken to understand the perspectives and mental health needs of rural children exposed to parental methamphetamine abuse. METHOD: Participants were 23 children involved with a state child protective agency because of parental methamphetamine abuse. A semistructured interview provided information on children's perspectives of their families. Information on children's mental health needs was obtained from the Child Behavior Checklist and Trauma Symptom Checklist. Case records and caseworker reports provided information on children's family experiences. RESULTS: Children described emotional pain; few social resources for coping with emotions, problem solving, or talking about their experiences; and avoidant or passive coping skills. Sixty-five percent of children evidenced significant dissociative or posttraumatic symptoms on standardized assessments; 57% had other significant emotional and behavioral problems. Challenges to understanding children's perspectives included children's perceptions that talking about methamphetamine abuse was taboo and underreporting of significant symptoms on the Trauma Symptom Checklist. CONCLUSIONS: The high rate of mental health problems suggests the need for nontraditional strategies for services delivery in rural areas that are targeted toward these vulnerable children. Early identification and treatment of mental health problems should be a priority. Clinicians should be alert to the complexities in assessing children's mental health needs. 相似文献
69.
TJ Freer 《Australian dental journal》2010,55(1):20-27
Australia has witnessed a proliferation of dental workforce training opportunities over the last 15 years, including dentists, dental therapists, dental hygienists and prosthetists. The reasons for this have not been examined critically. Universities have welcomed the opportunities to increase the student base but do not seem to have examined the advisability of continued expansion or its impact on the delivery and costs of health services. Nor have they enquired expressly whether they have any responsibility in these matters. Public health benefits should constitute a significant element of curriculum design. There seems to have been a general acceptance of the premise that more is necessarily better. Ironically, these developments have occurred in the face of significant recurrent cost increments and serious academic staff shortages. The schools have responded with alterations to curriculum content. Student cohort composition, course structures, educational focus, postgraduate training and research have been affected. The primary purpose of this review is to highlight the issues which currently drive workforce training and curriculum content and to suggest that some current practices should be re-examined as a starting point for setting defined common objectives within the Australian dental educational spectrum. Salient issues which require examination include course standards and accreditation, workforce mix, dental health demands, public service obligations and staffing profiles. 相似文献
70.
Lisanne M Verweij Karin I Proper Andre NH Weel Carel TJ Hulshof Willem van Mechelen 《BMC public health》2009,9(1):461-17