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排序方式: 共有3847条查询结果,搜索用时 15 毫秒
41.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献
42.
Naguib M. Zoheir Mona S. Hamdy Mervat M. Khorshied Nelly N. Abulata Mehry El Sobky Amr M. Saleh Hussein M. Khairy 《Comparative clinical pathology》2013,22(2):203-207
Deep vein thrombosis (DVT) is a common multi-factorial disease, with serious short- and long-term complications, and a potential fatal outcome. Many genes are involved in determining the interindividual variation in traits that define the onset and progression of disease, as well as the response to treatment. Several association studies have designed the relationship between factor XII C46T polymorphism and the risk of arterial and venous thrombosis. Some studies reported that FXII gene polymorphism is not associated with venous thrombosis, whereas other studies found an increased risk of venous thrombosis in carriers of a FXII-T variant. We constructed an age–gender–ethnic–matched case–control study including 52 DVT patients and 100 healthy volunteers. C46T polymorphism of the coagulation factor XII was carried out using allelic discrimination assay by real-time polymerase chain reaction for patients and controls, while plasma factor XII activity was detected by one-step clotting assay. FXII C46T genotyping in DVT patients revealed that 34.6% were heterozygous harboring the FXII-CT heterotype and 3.85% were homozygous; FXII-TT homotype, with no statistically significant difference in the distribution of the mutant genotypes between DVT patients and the control group. FXII activity was significantly reduced in DVT patients harboring the mutant genotypes. In the present study, FXII C46T gene polymorphism was not associated with increased risk of deep venous thrombosis. 相似文献
43.
Myeloproliferative neoplasms (chronic myeloproliferative disorders according to former nomenclature) comprise chronic myeloid leukemia, polycythemia vera, essential thrombocythemia, primary myelofibrosis, chronic eosinophilic leukemia, chronic neutrophilic leukemia and systemic mastocytosis. All disorders have excessive proliferation of one or more hematopoietic lineages in common and progress with different probability to blast crisis or fibrosis. A further common feature is provided by the activating mutation of tyrosin kinases and associated pathways of signal transduction (BCR-ABL, JAK2V617F, MPLW515L/K, KITD816V and FIP1L1-PDGFRA) causative for the abnormal proliferation. With regard to diagnosis and therapy these mutations are of utmost importance because they enable the exclusion of reactive processes, contribute with varying specificity to subtyping of MPN and are at least partly sensitive to targeted therapy. The molecular mechanisms of blastic and fibrotic progression are not yet understood. 相似文献
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45.
Adam M. Garber Robert J. Mentz Hussein R. Al-Khalidi Linda K. Shaw Mona Fiuzat Christopher M. O’Connor Eric J. Velazquez 《Journal of thrombosis and thrombolysis》2016,41(3):365-373
We aimed to characterize the independent predictors of LVT following STEMI and the association with outcomes. The clinical predictors of left ventricular thrombus (LVT) formation after ST-segment elevation myocardial infarction (STEMI) are not well-defined in the contemporary era. We performed a retrospective analysis of STEMI patients at Duke from 2000 to 2011 who had a transthoracic echocardiogram within 90 days post-STEMI and compared patients with and without LVT (LVT+ vs. LVT?). Univariate Cox proportional hazards regression models of baseline characteristics were examined and significant variables were used in a multivariable model to assess adjusted relationships with LVT. A multivariable Cox PH survival model with covariate adjustments was used for assessment of LVT and long-term mortality. Of all eligible patients, 1734 patients met inclusion criteria and 4.3 % (N = 74) had a LVT. LVT+ patients tended to have a history of heart failure (HF) and higher initial troponin compared to LVT- patients. After adjustment, higher heart rate, non-white race, HF severity, and presence of left anterior descending artery (LAD) disease were independent predictors of LVT. There was a trend toward an association between LVT and increased all-cause mortality (HR 1.36; 95 % CI 0.84–2.21, P = 0.22), however this was not statistically significant. LVT was seen in over 4 % of this contemporary post-STEMI population. Several baseline characteristics were independently associated with LVT: Heart rate, HF severity, LAD disease, and non-white race. Prospective studies are warranted to determine whether anticoagulation in patients at increased risk for LVT improves outcomes. 相似文献
46.
Ahmed Faeq Hussein Shaiful Jahari Hashim Ahmad Fazli Abdul Aziz Fakhrul Zaman Rokhani Wan Azizun Wan Adnan 《Journal of medical systems》2018,42(1):15
The non-stationary and multi-frequency nature of biomedical signal activities makes the use of time-frequency distributions (TFDs) for analysis inevitable. Time-frequency analysis provides simultaneous interpretations in both time and frequency domain enabling comprehensive explanation, presentation and interpretation of electrocardiogram (ECG) signals. The diversity of TFDs and specific properties for each type show the need to determine the best TFD for ECG analysis. In this study, a performance evaluation of five TFDs in term of ECG abnormality detection is presented. The detection criteria based on extracted features from most important ECG signal components (QRS) to detect normal and abnormal cases. This is achieved by estimating its energy concentration magnitude using the TFDs. The TFDs analyse ECG signals in one-minute interval instead of conventional time domain approach that analyses based on beat or frame containing several beats. The MIT-BIH normal sinus rhythm ECG database total records of 18 long-term ECG sampled at 128 Hz have been analysed. The tested TFDs include Dual-Tree Wavelet Transform, Spectrogram, Pseudo Wigner-Ville, Choi-Williams, and Born-Jordan. Each record is divided into one-minute slots, which is not considered previously, and analysed. The sample periods (slots) are randomly selected ten minutes interval for each record. This result with 99.44% detection accuracy for 15,735 ECG beats shows that Choi-Williams distribution is most reliable to be used for heart problem detection especially in automated systems that provide continuous monitoring for long time duration. 相似文献
47.
48.
Abdelfatah Elasfar Kafaf Jalali Mohamed Hussein Ibraheem AlHarbi Osama Amoudi 《Journal of the Saudi Heart Association》2018,30(3):268-270
The recommended anticoagulation regimen for continuous-flow left ventricular assist device (LVAD) systems is warfarin and aspirin with a targeted international normalized ratio (INR) of 2.0–3.0. Our patient is a 58-year-old male who underwent surgical HeartMate III continuous-flow LVAD implantation 3?months ago outside the country. The patient mistakenly stopped taking warfarin for 1?month prior to presenting to our center for a routine visit. Luckily, the patient was doing very well without any complication despite the fact that his INR was 1.0. 相似文献
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50.
Syed Fazal Hussein Shah BA 《Pediatric dermatology》2020,37(5):996-999
Toy manufacturer Mattel released a new line of diverse Barbie dolls earlier this year, including dolls with alopecia and vitiligo. The new dolls have been widely celebrated, with both media and dermatologists proposing that the dolls could provide significant benefits for the low self-esteem and societal exclusion suffered by children with similar dermatoses. However, the reality may be very different. Here, we present existing research on the impact of diverse dolls on children’s play and psychology to argue that the dolls’ proposed benefits for children with alopecia and vitiligo are unlikely to materialize; rather, alopecia and vitiligo Barbie could prove more harmful than beneficial. 相似文献