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101.

Purpose

Zr-89 positron emission tomography (PET) is a valuable tool for understanding the biodistribution and pharmacokinetics of antibody-based therapeutics. We compared the image quality of Zr-89 PET and F-18 PET in the Siemens microPET Focus 220 preclinical scanner using different reconstruction methods.

Procedures

Image quality metrics were measured in various Zr-89 and F-18 PET phantoms, including the NEMA NU 4-2008 image quality phantom. Images were reconstructed using various algorithms.

Results

Zr-89 PET had greater image noise, inferior spatial resolution, and greater spillover than F-18 PET, but comparable recovery coefficients for cylinders of various diameters. Of the reconstruction methods, OSEM3D resulted in the lowest noise, highest recovery coefficients, best spatial resolution, but also the greatest spillover. Scatter correction results were found to be sensitive to varying object sizes.

Conclusions

Zr-89 PET image quality was inferior to that of F-18, and no single reconstruction method was superior in all aspects of image quality.
  相似文献   
102.
In HIV-1–infected patients, increased numbers of circulating CD8+ T cells are linked to increased risk of morbidity and mortality. Here, we identified a bystander mechanism that promotes CD8 T cell activation and expansion in untreated HIV-1–infected patients. Compared with healthy controls, untreated HIV-1–infected patients have an increased population of proliferating, granzyme B+, CD8+ T cells in circulation. Vβ expression and deep sequencing of CDR3 revealed that in untreated HIV-1 infection, cycling memory CD8 T cells possess a broad T cell repertoire that reflects the repertoire of the resting population. This suggests that cycling is driven by bystander activation, rather than specific antigen exposure. Treatment of peripheral blood mononuclear cells with IL-15 induced a cycling, granzyme B+ phenotype in CD8+ T cells. Moreover, elevated IL-15 expression in the lymph nodes of untreated HIV-1–infected patients correlated with circulating CD8+ T cell counts and was normalized in these patients following antiretroviral therapy. Together, these results suggest that IL-15 drives bystander activation of CD8+ T cells, which predicts disease progression in untreated HIV-1–infected patients and suggests that elevated IL-15 may also drive CD8+ T cell expansion that is linked to increased morbidity and mortality in treated patients.  相似文献   
103.
ObjectiveTo identify the chikungunya outbreaks in both indoor and outdoor patients in some selected hospitals in our locality and the burden and magnitude of the disease, to compare different system of medicines (allopathic, Ayurvedic, homeopathy etc) and to explore the knowledge, attitude and practices of pharmacists and other health care professionals in the treatment of chikungunya.MethodsA six-month study was carried out. Detailed history was taken from the case history, personal interview of doctors and suspected cases. Personal data such as name age, sex, location, date of onset of illness, medical history, general/systemic examination features, drugs used (allopathy, Ayurveda, homeopathy, or traditional) for the treatment, etc. were noted down. A simple questionnaire was prepared and distributed to various doctors practicing various systems of medicines.ResultsA total of 209 suspected cases were identified from July to December, 2009. People in the age group of 20–40 years were more affected. The study revealed that females were more affected than males. The Grade-III (58.73%) population was more prone to chikungunya than Grade-II (38.75%) and Grade-I (2.87%). It showed that fever, pain in muscles, and sleeping disturbances were the intense symptoms of chikungunya. Myocarditis and arthritis were concomitant diseases which worsened chikungunya symptoms. It also indicated the effective medicine for compliance is nonsteroidal antiinflammatory drugs (NSAIDS).ConclusionsFrom our study we found that in some places there is no proper documentation, even though there are proper guidelines framed by the relevant authorities. It can be concluded from the study that all the systems of medicine are equally important for the management of chikungunya. Additional effort in promoting the guidelines at local level and proper documentation helps to achieve the goal of curbing the chikungunya. It is high time to increase our effort and promote these messages at grassroot level which benefits the society/community as a whole.  相似文献   
104.
BACKGROUND: Management of asthma involves adherence to medication regimens. Assessing adherence is difficult for health care providers and researchers. Self-reported medication use is subjective, so objective methods of data collection for medication use are frequently used in asthma research. The aim of this project is to examine the concordance between asthma medication pharmacy data culled from Medicaid claims data ("Medicaid pharmacy data") and patient pharmacy record data obtained from individual pharmacies ("pharmacy record data"). METHODS: Medicaid pharmacy data and pharmacy record data were obtained from inner-city children enrolled in a prospective study of children with persistent asthma. A subject level comparison of pharmacy records and Medicaid pharmacy data pharmacy records was done to determine concordance between the 2 data collection methods. RESULTS: Of 513 children recruited for inclusion, 221 were consented and randomized. Medicaid claims data were collected on 72.8% (n=161) of the 221 enrolled subjects. Pharmacy record data were available on 96.8% (n=214) of the 221 subjects. Data presented represent the 159 subjects who had both Medicaid claims data and pharmacy records data available throughout the study period. There was complete agreement between Medicaid pharmacy data and pharmacy record for 26% (n=42) of subjects. A total of 1858 asthma medication claims were captured by the Medicaid pharmacy data. Medicaid pharmacy data missed 149 claims that were capture by the pharmacy record data. Medicaid pharmacy data failed to capture a single claim on 4.4% (n=7) of subjects. The pharmacy record data captured a total of 1627 asthma medication claims and missed 371 claims that were captured by the Medicaid pharmacy data. Pharmacy record data failed to capture a single claim in 1.9% (n=3) of subjects. CONCLUSIONS: There was overlap between the pharmacy data captured by the Medicaid pharmacy dataset and pharmacy record dataset, but the overall concordance between the two data collection methods was low. Pharmacy records collected directly from the pharmacy included data on more subjects and pharmacy data culled from Medicaid claims captured more total number of claims. In spite of the differences in the methods used to collect data, pharmacy fill records are a rich source of data with both clinical and research applications. Clinicians and researchers must weigh the benefits and limitations of each method used to collect pharmacy data.  相似文献   
105.
106.
    
Widespread use of heart transplantation is limited by the scarcity of donor organs. Total artificial heart (TAH) development has been pursued to address this shortage, especially to treat patients who require biventricular support. We have developed a novel TAH that utilizes a continuously spinning rotor that shuttles between two positions to provide pulsatile, alternating blood flow to the systemic and pulmonary circulations without artificial valves. Flow rates and pressures generated by the TAH are controlled by adjusting rotor speed, cycle frequency, and the proportion of each cycle spent pumping to either circulation. To validate the design, a TAH prototype was placed in a mock circulatory loop that simulates vascular resistance, pressure, and compliance in normal and pathophysiologic conditions. At a systemic blood pressure of 120/80 mm Hg, nominal TAH output was 7.4 L/min with instantaneous flows reaching 17 L/min. Pulmonary artery, and left and right atrial pressures were all maintained within normal ranges. To simulate implant into a patient with severe pulmonary hypertension, the pulmonary vascular resistance of the mock loop was increased to 7.5 Wood units. By increasing pump speed to the pulmonary circulation, cardiac output could be maintained at 7.4 L/min as mean pulmonary artery pressure increased to 56 mm Hg while systemic blood pressures remained normal. This in vitro testing of a novel, shuttling TAH demonstrated that cardiac output could be maintained across a range of pathophysiologic conditions including pulmonary hypertension. These experiments serve as a proof‐of‐concept for the design, which has proceeded to in vivo testing.  相似文献   
107.
108.

Purpose

To investigate determinants of no-show rates in an academic pediatric otolaryngology practice including appointment time, age, sex, new patient status, payer mix, and median household income by zip code.

Materials and methods

Retrospective chart review of clinic no-show rates and patient demographics in a free standing children's hospital and affiliated outpatient clinics across eight providers in a one-year period.

Results

Analysis shows that the overall no-show rate across all providers was 15% with the highest rate of 19% in the zip code with the lowest median income. Highest no-shows are in June, but overall, seasons did not play a significant role in no-show rates. Male gender, morning appointments, and having public insurance appear to significantly predict no-shows. Lost revenue on no-shows range from $191K to $384K per year. The average percentage of the amount billed paid by insurance range from the lowest by out-of-state Medicaid at 16% to the highest by managed care at 54%.

Conclusions

No-show rates account for a significant portion of lost revenue in the outpatient setting for an academic practice, and can be predicted by lower median income, male gender, morning appointments, and public insurance. Such patients may need different appointment reminders. Future clinic templates should be optimized for no-shows to increase productivity and access to care.  相似文献   
109.
110.

Objective

Examine outcomes of varied postoperative sedation management in pediatric patients recovering from single stage laryngotracheal reconstruction.

Design

Retrospective review of 34 patients treated with single stage laryngotracheal reconstruction from 2001 through 2011.

Setting

Tertiary children's hospital.

Methods

Patients were divided into 2 groups: those managed postoperatively with sedation, with or without paralysis (group 1), and those managed awake with narcotic pain medication as needed for primary management (group 2). Outcomes were measured as a function of sedation management. Outcomes investigated focused on those related to the success of the airway reconstruction, and those related to sedation management.

Results

Out of 68 cases of laryngotracheal reconstruction reviewed from 2001 to 2011, 34 were single stage reconstructions. Nineteen patients were sedated postoperatively (group 1) and fifteen patients were left awake (group 2). There were no significant differences between groups in airway-related outcomes, including risk of accidental decannulation, revision rates, and need for secondary airway procedures such as balloon dilation. Sedation-related outcomes, specifically focusing on differences in medical management, showed significant increases in rates of withdrawal (p < 0.0001), nursing concerns of withdrawal (p < 0.0001) and sedation level (p < 0.0001), pulmonary complications (OR 7.7, p = 0.008), and prolonged hospital stay due to withdrawal (p = 0.0005) in patients managed with sedation with or without paralysis. Multivariable regression analysis revealed that duration of sedation was the primary risk factor for increased postoperative morbidity, while younger age, lower weight, and use of a posterior graft were also significant variables assessed.

Conclusion

Avoiding sedation as the standard for postoperative management of single stage laryngotracheal reconstruction airway patients leads to an overall decreased risk of morbidity without increasing risk of airway-specific morbidity. This is specifically as related to withdrawal, pulmonary complications, concerns about sedation level and prolonged hospital course, all of which increase significantly with increased level and duration of sedation.  相似文献   
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