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91.
The present study aimed to assess the effects of low-level laser therapy (GaAlAs) on the bone repair process within titanium scaffolds in the femurs of healthy and osteoporotic rats. Fifty-six rats were divided into four groups: group Sh: SHAM animals that received scaffolds; group LSh: SHAM animals that received scaffolds and were subjected to laser therapy; group OV: ovarietomized (OVX) animals that received scaffolds; and group LOV: OVX animals that received scaffolds and were subjected to laser therapy. Thirty days following ovariectomy or sham surgery, scaffolds were implanted in the left femurs of all animals in the study. Immediately after opening the surgical site, the inner part of the surgical cavity was stimulated with low-level laser (GaAlAs). In addition to this procedure, the laser group was also subjected to sessions of low-level laser therapy (LLLT) at 48-h intervals, with the first session performed immediately after surgery. The rats were sacrificed at 2 and 6 weeks, time in which femur fragments were submitted for histological and histomorphometric examination, and skin tissue above the scaffold was submitted to histological analysis. At the end of the study, greater bone formation was observed in the animals submitted to LLLT. At 2 and 6 weeks, statistically significant differences were observed between LSh and Sh groups (p?=?0.009 and 0.0001) and LOV and OV (p?=?0.0001 and 0.0001), respectively. No statistical difference was observed when assessing the estrogen variable. On the basis of our methodology and results, we conclude that LLLT improves and accelerates bone repair within titanium scaffolds in both ovariectomized and healthy rats, when compared to animals not subjected to radiation.  相似文献   
92.
Management of carotid bifurcation stenosis is a cornerstone of stroke prevention and has been the subject of extensive clinical investigation, including multiple controlled randomized trials. The appropriate treatment of patients with carotid bifurcation disease is of major interest to the community of vascular surgeons. In 2008, the Society for Vascular Surgery published guidelines for treatment of carotid artery disease. At the time, only one randomized trial, comparing carotid endarterectomy (CEA) and carotid stenting (CAS), had been published. Since that publication, four major randomized trials comparing CEA and CAS have been published, and the role of medical management has been re-emphasized. The current publication updates and expands the 2008 guidelines with specific emphasis on six areas: imaging in identification and characterization of carotid stenosis, medical therapy (as stand-alone management and also in conjunction with intervention in patients with carotid bifurcation stenosis), risk stratification to select patients for appropriate interventional management (CEA or CAS), technical standards for performing CEA and CAS, the relative roles of CEA and CAS, and management of unusual conditions associated with extracranial carotid pathology. Recommendations are made using the GRADE (Grades of Recommendation Assessment, Development and Evaluation) system, as has been done with other Society for Vascular Surgery guideline documents.[corrected] The perioperative risk of stroke and death in asymptomatic patients must be <3% to ensure benefit for the patient. CAS should be reserved for symptomatic patients with stenosis of 50% to 99% at high risk for CEA for anatomic or medical reasons. CAS is not recommended for asymptomatic patients at this time. Asymptomatic patients at high risk for intervention or with <3 years life expectancy should be considered for medical management as the first-line therapy.  相似文献   
93.
By going to millimeter wave (mmWave) we can use large scale MIMO due to short mmWave wavelength to overcome path loss by using beamforming to focus power of signal to the receiver. System structure of mmWave band is different with conventional MIMO because of large scale MIMO which is leading to use many RF-chains. For this reason Hybrid structure have been proposed for large Scale MIMO. By going to Hybrid structure a new issue has been created with phase shifter constraint. In this paper we propose a novel solution to make a hybrid precoding and combing to reach high spectral efficiency. Our problem includes a maximizing Frobenius norm of multiplying five complex matrices. As constraints, all elements of some matrices must have unit norm, and also the multiplication of some matrices must have a specific Frobenius norm. A novel solution is proposed for the problem, which is gained in two steps. At the first step, we propose a new decomposition usable for kind of complex matrices which could lead to reduce the dimension of the objective function, and eliminating constraints completely and in the second step, we propose an iterated algorithm for the resulting problem. By proposing another novel technique, we show that in each iteration, the optimal problem is equivalent to a quadratic optimal problem with limitations on the vector norm, and as a result, an optimal problem is obtained quickly. Moreover, some other real examples are included to demonstrate the usefulness and effectiveness of the proposed algorithm.  相似文献   
94.
166Ho-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene-phosphonate (DOTMP) is a tetraphosphonate molecule radiolabeled with 166Ho that localizes to bone surfaces. This study evaluated pharmacokinetics and radiation-absorbed dose to all organs from this beta-emitting radiopharmaceutical. METHODS: After two 1.1-GBq administrations of 166Ho-DOTMP, data from whole-body counting using a gamma-camera or uptake probe were assessed for reproducibility of whole-body retention in 12 patients with multiple myeloma. The radiation-absorbed dose to normal organs was estimated using MIRD methodology, applying residence times and S values for 166Ho. Marrow dose was estimated from measured activity retained after 18 h. The activity to deliver a therapeutic dose of 25 Gy to the marrow was determined. Methods based on region-of-interest (ROI) and whole-body clearance were evaluated to estimate kidney activity, because the radiotracer is rapidly excreted in the urine. The dose to the surface of the bladder wall was estimated using a dynamic bladder model. RESULTS: In clinical practice, gamma-camera methods were more reliable than uptake probe-based methods for whole-body counting. The intrapatient variability of dose calculations was less than 10% between the 2 tracer studies. Skeletal uptake of 166Ho-DOTMP varied from 19% to 39% (mean, 28%). The activity of 166Ho prescribed for therapy ranged from 38 to 67 GBq (1,030-1,810 mCi). After high-dose therapy, the estimates of absorbed dose to the kidney varied from 1.6 to 4 Gy using the whole-body clearance-based method and from 8.3 to 17.3 Gy using the ROI-based method. Bladder dose ranged from 10 to 20 Gy, bone surface dose ranged from 39 to 57 Gy, and doses to other organs were less than 2 Gy for all patients. Repetitive administration had no impact on tracer biodistribution, pharmacokinetics, or organ dose. CONCLUSION: Pharmacokinetics analysis validated gamma-camera whole-body counting of 166Ho as an appropriate approach to assess clearance and to estimate radiation-absorbed dose to normal organs except the kidneys. Quantitative gamma-camera imaging is difficult and requires scatter subtraction because of the multiple energy emissions of 166Ho. Kidney dose estimates were approximately 5-fold higher when the ROI-based method was used rather than the clearance-based model, and neither appeared reliable. In future clinical trials with 166Ho-DOTMP, we recommend that dose estimation based on the methods described here be used for all organs except the kidneys. Assumptions for the kidney dose require further evaluation.  相似文献   
95.

Background:

Percutaneous vertebroplasty (PVP) is more commonly used for osteoporotic compression fractures (OCFs) and osteolytic vertebral body tumors. This study aimed to study the differences between OCFs and vertebral hemangiomas (VHs) treated with PVP.

Materials and Methods:

Between September 2007 and January 2010, we prospectively treated 28 consecutive patients of OCFs (43 recently symptomatic OCFs) and 24 cases of VHs (26 VHs). We used visual analogue scale (VAS) pain and Oswestry Disability Index (ODI) to evaluate the patients. The followup period in group 1 and 2 were 25.1 months (range 12 - 31 months) and 21.3 months (range 14 - 28 months), respectively. Comparison of means was carried out with the Chi Square Tests, t-test, and N Par-Test for multiple comparisons, whenever appropriate. The level of statistical significance was set at P < 0.05.

Results:

Following PVP the VAS score decreased to 4.57 and 4.17 in group 1 and 2, respectively. The ODI scores were 32.5% and 30%, respectively. This decrease in ODI scores lasted throughout the followup period.

Conclusions:

Although the preoperative scores were significantly different between group 1 and 2, there was no significant difference between two groups following the PVP.  相似文献   
96.
97.

Background

Burns are one of the most significant health problems throughout the world, leading to prolonged hospitalisation and hence increased expense for the patients, their families and society. Today, the prognosis of patients with burns is dependent, apart from adequate treatment, upon the health-care system and health-care professionals, regarding not only survival, but also lifelong quality of life. This study aims to assess quality of life of adult patients with severe burns.

Patients and methods

This study was conducted on 100 adult patients with severe burns in the burn outpatient clinic (male and female) at Mansoura University Hospital. Parameters of burn and Burn Specific Health Scale (BSHS-B) were used to assess quality of life following burns.

Results

The study revealed that burns has negative impact on most dimensions of the quality of life of patients with burns.

Conclusions

The quality of life for people who have sustained a burns should be recognised and valued by the burn team in all phases of burn care.  相似文献   
98.
Purpose: To evaluate the return to work (RTW) rate, time and predictors among trauma patients using survival analysis. Methods: This cohort study was conducted with a three-month follow-up on 300 trauma patients hospitalized in Shahid Beheshti Hospital, Kashan, Iran in 2014. The data were collected through conducting interviews and referring to patients'' medical records during their hospital stay and follow-up information at one & three months after discharge from hospital. Final analysis was conducted on the data retrieved from 273 patients. Data were analyzed by chi-square test, ManneWhitney U test and survival analysis method. Results: The rate of RTW at the end of the first and the third follow-up months was respectively 21.6% and 61.2%. Survival analysis showed that the RTW time (Time between admission to first return to work) was significantly longer among patients with illiteracy, drug abuse, hospitalization history in the intensive care unit, low socioeconomic status, non-insurance coverage, longer hospital stay, multiple and severe injuries as well as severe disability. Conclusion: Our findings indicated that trauma has profound effects on the rate and time of RTW. Besides disability, many personal and clinical factors can affect the outcome of RTW.  相似文献   
99.
100.
Cytomegalovirus (CMV) is the most important infectious agent in solid organ transplant recipients and has a major impact on morbidity and mortality. Most cases are well managed with antiviral agents, but CMV hyperimmune globulin (CMVIg) can be used alongside antiviral therapy for prophylaxis in high‐risk thoracic organ recipients and to treat life‐threatening CMV infection or disease. CMVIg may also improve antiviral host defences when genetic resistance to antivirals or unwanted side effects occur. In this single‐center, retrospective study, we reviewed the CMVIg use to supplement antiviral therapy as a “rescue therapy” in cardiothoracic transplant recipients. These comprised 12 single lung, 11 double lung, and 12 heart transplant recipients. Patients received a median of 2 doses of CMVIg, most often in combination with ganciclovir or valganciclovir, and reduced immunosuppression. One week after rescue therapy was initiated, CMV DNA levels were significantly reduced, and after four weeks, CMV DNA was undetectable in 73% patients. Only one patient died as a result of CMV‐related disease. No significant adverse effects were observed. We conclude that CMVIg rescue therapy is safe, well tolerated, and effective at controlling viral replication in cardiothoracic transplant recipients.  相似文献   
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