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21.
22.
Comparison of anatomic and neurophysiological methods for subthalamic nucleus targeting 总被引:13,自引:0,他引:13
Zonenshayn M Rezai AR Mogilner AY Beric A Sterio D Kelly PJ 《Neurosurgery》2000,47(2):282-92; discussion 292-4
OBJECTIVE: The subthalamic nucleus (STN) has recently become the surgical target of choice for the treatment of medically refractory idiopathic Parkinson's disease. A number of anatomic and physiological targeting methods have been used to localize the STN. We retrospectively reviewed the various anatomic targeting methods and compared them with the final physiological target in 15 patients who underwent simultaneous bilateral STN implantation of deep brain stimulators. METHODS: The x, y, and z coordinates of our localizing techniques were analyzed for 30 STN targets. Our final targets, as determined by single-cell microelectrode recording, were compared with the following: 1) targets selected on coronal magnetic resonance inversion recovery and T2-weighted imaging sequences, 2) the center of the STN on a digitized scaled Schaltenbrand-Wahren stereotactic atlas, 3) targeting based on a point 13 mm lateral, 4 mm posterior, and 5 mm inferior to the midcommissural point, and 4) a composite target based on the above methods. RESULTS: All anatomic methods yielded targets that were statistically significantly different (P < 0.001) from the final physiological targets. The average distance error between the final physiological targets and the magnetic resonance imaging-derived targets was 2.6 +/- 1.3 mm (mean +/- standard deviation), 1.7 +/- 1.1 mm for the atlas-based method, 1.5 +/- 0.8 mm for the indirect midcommissural method, and 1.3 +/- 1.1 mm for the composite method. Once the final microelectrode-refined target was determined on the first side, the final target for the contralateral side was 1.3 +/- 1.2 mm away from its mirror image. CONCLUSION: Although all anatomic targeting methods provide accurate STN localization, a combination of the three methods offers the best correlation with the final physiological target. In our experience, direct magnetic resonance targeting was the least accurate method. 相似文献
23.
Achieving optimal outcomes after radical prostatectomy. 总被引:4,自引:0,他引:4
Jeffery W Saranchuk Michael W Kattan Elena Elkin A Karim Touijer Peter T Scardino James A Eastham 《Journal of clinical oncology》2005,23(18):4146-4151
PURPOSE: The most favorable outcome that can be achieved after radical prostatectomy is complete tumor resection without recurrence and full recovery of continence and potency. Risks of erectile dysfunction, incontinence, and disease recurrence are well described, but in isolation, do not adequately inform patients of the possibility of becoming cancer-free while at the same time returning to their preoperative functional state. We sought to determine the frequency of optimal outcomes after radical prostatectomy and the time to such outcomes. PATIENTS AND METHODS: Patients who underwent radical prostatectomy performed at a tertiary referral center between July 1998 and July 2003 for clinical stage T1 to T3 prostate cancer were identified. Patients were excluded if they were incontinent or impotent preoperatively, or if they had received radiotherapy or neoadjuvant androgen deprivation therapy previously. Six hundred forty-seven patients were analyzed for time to recovery of full continence and potency without cancer recurrence after surgery. Optimal outcome probability was calculated with a Markov state transition model to simulate clinical outcomes in the first 4 years following radical prostatectomy. RESULTS: Mean patient age was 58 years, and mean pretreatment prostate-specific antigen was 6.9 ng/mL. Cancer-free status with full continence and potency was achieved in 30% of men at 12 months, 42% at 24 months, 47% at 36 months, and 53% at 48 months postoperatively. CONCLUSION: Optimal outcomes after radical prostatectomy can be achieved in a small majority of cases. Time to full recovery is primarily dictated by recovery of erectile function. This information is helpful for patients interested in their chances of returning to their preoperative functional state. 相似文献
24.
Ysmael Verde-Gmez Elizabeth Montiel-Macías Ana María Valenzuela-Muiz Ivonne Alonso-Lemus Mario Miki-Yoshida Karim Zaghib Nicolas Brodusch Raynald Gauvin 《Materials》2022,15(10)
In the past few decades, nanostructured carbons (NCs) have been investigated for their interesting properties, which are attractive for a wide range of applications in electronic devices, energy systems, sensors, and support materials. One approach to improving the properties of NCs is to dope them with various heteroatoms. This work describes the synthesis and study of sulfur-added carbon nanohorns (S-CNH). Synthesis of S-CNH was carried out by modified chemical vapor deposition (m-CVD) using toluene and thiophene as carbon and sulfur sources, respectively. Some parameters such as the temperature of synthesis and carrier gas flow rates were modified to determine their effect on the properties of S-CNH. High-resolution scanning and transmission electron microscopy analysis showed the presence of hollow horn-type carbon nanostructures with lengths between 1 to 3 µm and, diameters that are in the range of 50 to 200 nm. Two types of carbon layers were observed, with rough outer layers and smooth inner layers. The surface textural properties are attributed to the defects induced by the sulfur intercalated into the lattice or bonded with the carbon. The XRD patterns and X-ray microanalysis studies show that iron serves as the seed for carbon nanohorn growth and iron sulfide is formed during synthesis. 相似文献
25.
Ouldim K Sbiti A Natiq A El-Kerch F Cherkaoui S Sefiani A 《Fertility and sterility》2008,90(5):2013.e13-2013.e15
26.
Blohmer JU Kimmig R Kummel S Costa SD Kramer S Rezai M 《Gyn?kologisch-geburtshilfliche Rundschau》2008,48(2):63-67
In the systemic therapy of breast cancer, the tumor itself has become the specific target. If possible the surgical excision of breast carcinoma is restricted to the tumor site and aims at an R0 resection of the invasive and preinvasive portions of the carcinoma. Only percutaneous whole-breast radiotherapy irradiates the whole breast. The additional boost irradiation is targeted and significantly improves local control in all age groups. Due to the increased detection of small breast carcinomas in postmenopausal patients by mammographic screening, it is necessary to consider a change of the existing therapeutic practice. Published results of partial irradiation of the breast (intra- as well as postoperatively) show a very high degree of local control with follow-ups of up to 11 years. At present prospective and randomized studies investigate for which patients an intraoperative radiotherapy is sufficient as the sole irradiation method after previous surgery. Intraoperative radiotherapy as a boost preceding percutaneous whole-breast irradiation should already be possible according to a relevant statement of the DEGRO. 相似文献
27.
It is important for any woman undergoing mastectomy to make an informed decision about reconstruction and to be provided with information about the technique, advantages and disadvantages. There is a high degree of patient satisfaction with breast reconstruction, but high levels of preoperative information and psychological support are necessary. Close collaboration between oncological and reconstructive surgeons or management by an oncoplastic breast surgeon, careful patient selection and counseling, and refinements in surgical techniques can provide a range of safe and predictable techniques for breast reconstruction. After modified radical mastectomy breast reconstruction involves replacement of breast skin and breast volume; after skin-sparing mastectomy only the replacement of breast volume is necessary. The most commonly used surgical techniques are tissue expansion, latissimus dorsi myocutaneous flap with or without implants, and the use of lower abdominal tissue. Until today, the pedicled TRAM flap is the standard method for autologous breast reconstruction. 相似文献
28.
Kalache KD Mkhitaryan M Bamberg C Roehr CC Wauer R Mau H Bollmann R 《Prenatal diagnosis》2007,27(4):322-326
OBJECTIVES: The purpose of this retrospective study was to determine whether objective assessment of cardiac shifting on two-dimensional ultrasonography can predict postnatal outcome in fetuses with isolated left-sided congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: Still images at the level of the four-chamber view were obtained in 23 fetuses with left-sided CDH. A group of 12 fetuses (3 non-survivors and 9 survivors) were examined at two periods, between 20 and 30 weeks and between 31 and 40 weeks. A further 11 fetuses (2 non-survivors and 9 survivors) were examined between 31 and 40 weeks. Fetal heart axis and position were determined manually and associated with postnatal outcome. RESULTS: The cardiac axis remained constant in the 9 survivors (15.5 +/- 3.2 versus 17.2 +/- 3.3, p = 0.71) and 3 non-survivors (19.0 +/- 11.5 versus 18.5 +/- 11.8, p = 0.97). There was no statistical difference between the 9 survivors and 3 non-survivors at the two periods. Cardiac displacement remained constant in the 9 survivors (0.2 +/- 0.02 versus 0.2 +/- 0.02, p = 0.32) but increased significantly in the 3 non-survivors (0.2 +/- 0.04 versus 0.4 +/- 0.02, p = 0.015). The difference between survivors and non-survivors was statistically significant between the18 survivors and 5 non-survivors examined between 31 and 40 weeks of gestation (0.2 +/- 0.02 versus 0.4 +/- 0.02, p = 0.037). CONCLUSION: This study does not support the hypothesis that objective assessment of mediastinal shift in fetuses with left-sided CDH has a role in predicting postnatal outcome before fetal viability, which is when it would be more useful for counseling patients regarding whether to continue with the pregnancy or to opt for termination. 相似文献
29.
30.
Mustafa Abdul Karim Shuja M. Reagu Sami Ouanes Abdul Waheed Khan Wesam S. Smidi Nadeen Al-Baz Majid Alabdulla 《Medicine》2022,101(26)
Older individuals are more vulnerable to severe coronavirus disease 2019 and medical complications. Vaccination stands as an efficient and safe vanguard against infection. However, negative attitudes and perceptions pertaining to available vaccines might hinder community inoculation. The aim of this study was to assess vaccine hesitancy and its psychosocial determinants among the elderly in Qatar.We conducted a cross-sectional study between October 15 and November 15, 2020, using a composite online survey including the Vaccine Attitudes Examination Scale in addition to questions on sociodemographic correlates and the role of healthcare professionals.The vaccine hesitancy rate was 19.5%. The main reasons for willingness to vaccinate included understanding the nature of disease and role of vaccination, in addition to information provided by physicians. Fears mainly centered around vaccine safety. Vaccine hesitators were more likely to be non-Qatari and having received the influenza vaccine at least once. Gender, marital status, socioeconomic status, educational level, and having completed childhood vaccinations were not associated with vaccine hesitancy.Efforts should be directed toward raising awareness of vaccine efficacy and safety profiles. Physicians should additionally be educated about their pivotal role in advocating vaccine acceptance. We recommend reassessing vaccine hesitancy and its associated factors following a year of campaigning and vaccine administration to identify and target vulnerable groups. 相似文献