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301.
BACKGROUND:The use of ultrasound(US)within healthcare has inspired the development of new US technology.There have been few studies comparing the use of handheld US to standard US for medical education.This research aims to determine whether a handheld US device can provide a comparable primary learning experience to that of a standard US machine.METHODS:Over two days of instruction,participants were taught and evaluated on core US fundamentals.The standard group received instruction on standard US machines,while the handheld group received instruction on handheld US devices.Participants completed a qualitative survey regarding their experience.Six hundred and four images were obtained and graded by two emergency medicine physicians.RESULTS:A total of 119 Swiss medical students were enrolled in our study.There was no statistically significant difference in the US assessment measurements,except for faster endpoint septal separation(EPSS)vascular setup time in the handheld group(P=0.001).There was no statistically significant difference in participants’perceived difficulty of US learning(P=0.198),comfort level(P=0.188),or self-estimated capability to perform US in the future(P=0.442).There was no statistically significant difference in the percentage of correctly obtained images(P=0.211)or images that were clinically useful(P=0.256).The median quality score of images obtained by the standard group was eight compared to seven in handheld group(P<0.01).CONCLUSION:Our data suggest a handheld US machine can perform as well as a standard US machine as an educational tool despite sacrifices in image quality.  相似文献   
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Inflammasomes are a group of multimolecular intracellular complexes assembled around several innate immune proteins. Recognition of a diverse range of microbial, stress and damage signals by inflammasomes results in direct activation of caspase-1, which subsequently induces the only known form of secretion of active interleukin-1β and interleukin-18. Although the importance of interleukin-1β in the periodontium is not questioned, the impact of inflammasomes in periodontal disease and its potential for therapeutics in periodontology is still in its very early stages. Increasing evidence in preclinical models and human data strongly implicate the involvement of inflammasomes in a number of inflammatory, autoinflammatory and autoimmune disorders. Here we review: (a) the currently known inflammasome functions, (b) clinical/preclinical data supporting inflammasome involvement in the context of periodontal and comorbid diseases and (c) potential therapies targeting inflammasomes. To clarify further the inflammasome involvement in periodontitis, we present analyses of data from a large clinical study (n = 5809) that measured the gingival crevicular fluid-interleukin-1β and grouped the participants based on current periodontal disease classifications. We review data on 4910 European-Americans that correlate 16 polymorphisms in the interleukin-1B region with high gingival crevicular fluid-interleukin-1β levels. We show that inflammasome components are increased in diseased periodontal tissues and that the caspase-1 inhibitor, VX-765, inhibits ~50% of alveolar bone loss in experimental periodontitis. The literature review further supports that although patients clinically present with the same phenotype, the disease that develops probably has different underlying biological pathways. The current data indicate that inflammasomes have a role in periodontal disease pathogenesis. Understanding the contribution of different inflammasomes to disease development and distinct patient susceptibility will probably translate into improved, personalized therapies.  相似文献   
304.
An oronasal fistula is a passage between the oral and nasal cavity. Currently, surgical procedures use mucosal flaps or collagen grafts to make a barrier between oral and nasal cavities. Our aim was to develop a cell‐free synthetic repair material for closure of nasal fistulas. We surface functionalized electrospun polyurethane (PU) and poly‐L‐lactic acid (PLLA) and composite polymer (PU‐PLLA) membranes with acrylic acid through plasma polymerization. Membranes were treated in a layer‐by‐layer approach to develop highly charged electrostatic layer that could bind heparin as a pro‐angiogenic glycosaminoglycan. The properties were evaluated through physical, chemical, and mechanical characterization techniques. Cytotoxicity was tested with MC3T3 pre‐osteoblast cell lines for 3, 7, and 14 days, and vasculogenesis was assessed by implantation into the chorio‐allantoic membrane in chick embryos for 7 days. In vivo biocompatibility was assessed by subcutaneous implantation in rats for 1, 3, and 6 weeks. The membranes consisted of random fibers of PLLA‐PU with fiber diameters of 0.47 and 0.12 μm, respectively. Significantly higher cell proliferation and migration of MC3T3 cells at 3, 7, and 14 days were shown on plasma‐coated membranes compared with uncoated membranes. Further, it was found that plasma‐coated membranes were more angiogenic than controls. In vivo implantation of membranes in rats did not reveal any gross toxicity to the materials, and wound healing was comparable with the native tissue repair (sham group). We therefore present a plasma‐functionalized electrospun composite polymer membrane for use in the treatment of fistulas. These membranes are flexible, non‐cytotoxic, and angiogenic, and we hope it should lead to permanent closure of oronasal fistula.  相似文献   
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306.

Background/Objective:

To determine the prevalence of traumatic spinal cord injury (SCI) in Tehran, Iran.

Methods:

A population-based study was performed. In a random cluster sampling, 100 addresses were selected as the starting point of the survey for each cluster consisting of 25 households. To expand the geographic dimension of each cluster, the interviewers skipped 3 of 4 houses in gathering data for each study unit. Each person with traumatic SCI was evaluated initially by a nurse and then by a neurosurgeon by physical examination and spinal imaging at the hospital or at home.

Results:

Ninety-seven percent of all surveyed agreed to participate in the study (2,425 households, or 9,006 persons). Four cases of SCI were identified. The point prevalence of SCI was 4.4 [95% CI  =  1.2–11.4] per 10,000 people. Over the 5-year period from January 2003 through January 2008, the reported incidence rate of SCI was 2.2 (95% CI  =  0.27–8.00) per 10,000 people.

Conclusions:

In this, the first published population-based study from Iran, the prevalence of traumatic SCI in Tehran ranged from 1.2 to 11.4 per 10,000 people. More research is required to determine the patterns and causes of SCI. Development of a nationwide SCI registry or surveillance system is fundamental to an understanding of the epidemiology, and hence the prevention, of this costly health problem.  相似文献   
307.
Objective: Injuries are common and important problem in Tehran, capital of Iran. Although therapeutic centers are not essentially established following the constructional principles of developed countries, the present opportunities and equipments have to be used properly. We should recognize and reduce the deficits based on the global standards.This study deliberates the trauma resources and capacities in university hospitals of Tehran based on Arizona trauma center standards, which are suitable for the assessment of trauma centers.Methods: Forty-one university hospitals in Tehran were evaluated for their conformity with "Arizona trauma center standards" in 2008. A structured interview was arranged with the "Educational Supervisor" of all hospitals regarding their institutional organization, departments, clini-cal capabilities, clinical qualifications, facilities and resources, rehabilitation services, performance improvement, continuing education, prevention, research and additional requirements for pediatric trauma patients. Relative frequencies and percentages were calculated and Student's t test was used to compare the mean values.Results: Forty-one hospitals had the average of 77.7 (50.7%) standards from 153 Arizona trauma center standards and these standards were present in 97.5 out of 153 (63.7%) in 17 general hospitals. Based on the subgroups of the standards, 64.8% items of hospital resources and capabilities were considered as a subgroup with the maximum criteria, and 17.7% items of research section as another subgroup with the minimum standards.Conclusions: On the basis of our findings, no hospital meet all the Arizona trauma center standards completely. The hospitals as trauma centers at different levels must be promoted to manage trauma patients desirably.  相似文献   
308.
Rapid quantitative methods for characterizing small molecules, peptides, proteins, or RNAs in a broad array of cellular assays would allow one to discover new biological activities associated with these molecules and also provide a more comprehensive profile of drug candidates early in the drug development process. Here we describe a robotic system, termed the automated compound profiler, capable of both propagating a large number of cell lines in parallel and assaying large collections of molecules simultaneously against a matrix of cellular assays in a highly reproducible manner. To illustrate its utility, we have characterized a set of 1,400 kinase inhibitors in a panel of 35 activated tyrosine-kinase-dependent cellular assays in dose-response format in a single experiment. Analysis of the resulting multidimensional dataset revealed subclusters of both inhibitors and kinases with closely correlated activities. The approach also identified activities for the p38 inhibitor BIRB796 and the dual src/abl inhibitor BMS-354825 and exposed the expected side activities for Glivec/STI571, including cellular inhibition of c-kit and platelet-derived growth factor receptor. This methodology provides a powerful tool for unraveling the cellular biology and molecular pharmacology of both naturally occurring and synthetic chemical diversity.  相似文献   
309.
Schizophrenia is highly heritable, but the specific genes involved remain to be determined. A genome wide scan approach has indicated that human chromosome 22q11.2 potentially influences schizophrenia susceptibility. The gene encoding glutathione S-transferase T1 (GSTT1), which pertains to phase II biotransformation enzymes, was also mapped to the above-mentioned band. The present case-control study was performed on 292 (206 males, 86 females) in-patients with schizophrenia, and a total of 292 healthy blood donors matched to the patients according to age (+/-5 years) and gender as a control group. The patients were chronic cases. The patients were diagnosed as chronic schizophrenia according to structured clinical interview using the Structured Clinical Interview for DSM-IV (clinician version) to confirm and document DSM-IV diagnosis. The GSTT1 genotypes were determined using a PCR-based method. The GSTT1 null genotype was 17.8% and 33.9% in the patients and control groups, respectively. The GSTT1 null genotype was associated with a significantly reduced risk of developing schizophrenia. On the other word, the positive GSTT1 genotype significantly increased the risk of schizophrenia. The present finding indicated that GSTT1 is a candidate gene for susceptibility to schizophrenia.  相似文献   
310.
To assess the extent of atherothrombosis and the use of the ankle-brachial index (ABI) in populations from the Middle East, we conducted a multicenter study similar to AGATHA (a Global Atherothrombosis Assessment), AGATHA-ME, which included 1341 patients from 18 centers from 5 countries (United Arab Emirates, Kuwait, Qatar, Bahrain, and Oman). Patients were assigned to 2 groups: the with-disease and at-risk groups. Abnormal ABI (< or =0.9) was seen in 31.5% of at-risk patients and 28.2% of with-disease patients. Patients with peripheral arterial disease had the highest frequency of abnormal ABI (77.6%), with 97.8 negative predictive value. The AGATHA-ME study confirms that atherothrombosis disease often occurs at more than 1 site. The ABI is related to the risk factor profile and to the site and extent of atherothrombosis. Gender and diabetes mellitus are associated with the worst parameters.  相似文献   
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