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BACKGROUND AND PURPOSE:The current Neck Imaging Reporting and Data System (NI-RADS) criteria were designed for contrast-enhanced CT with or without PET. Prior studies have revealed the capability of DWI and T2 signal intensity in distinguishing locoregional tumor residual and recurrence from posttreatment benign findings in head and neck cancers. We aimed to propose MR imaging NI-RADS criteria by adding diffusion criteria and T2 signal intensity to the American College of Radiology NI-RADS template.MATERIALS AND METHODS:This retrospective study included 69 patients with head and neck squamous cell carcinoma (HNSCC) who underwent posttreatment contrast-enhanced MRI imaging surveillance using a 1.5T scanner. The scans were interpreted by 2 neuroradiologists. Image analysis assessed the primary tumor site using the current American College of Radiology NI-RADS morphologic lexicon (mainly designed for contrast-enhanced CT with or without PET). NI-RADS rescoring was then performed based on our proposed criteria using T2 signal and diffusion features. The reference standard was a defined set of criteria, including clinical and imaging follow-up and pathologic assessment.RESULTS:Imaging assessment of treated HNSCC at the primary tumor site using T2 signal intensity and diffusion features as modifying rules to NI-RADS showed higher sensitivity, specificity, positive predictive value, negative predictive value, and accuracy (92.3%, 90.7%, 85.7%, 95.1%, and 91.3%, respectively) compared with the current NI-RADS lexicon alone (84.6%, 81.4%, 73.3%, 89.8%, and 82.6%, respectively).CONCLUSIONS:The addition of diffusion features and T2 signal to the American College of Radiology NI-RADS criteria for the primary tumor site enhances the specificity, sensitivity, positive predictive value, negative predictive value, and NI-RADS accuracy.

The Neck Imaging Reporting and Data System (NI-RADS) was recently introduced by the American College of Radiology (ACR) to precisely convey the level of radiologic suspicion regarding the existence of a recurrent or residual disease.1,2 Initial studies showed high performance of the NI-RADS system.3,4 NI-RADS criteria and risk categories were developed for contrast-enhanced CT (CECT) imaging with or without PET for posttreatment neck imaging. Later, these risk categories were applied to contrast-enhanced MRI (CEMRI).1,2,5 However, there is still no published ACR NI-RADS lexicon for MR imaging surveillance.Although not included in the NI-RADS scoring system, several studies have revealed the usefulness of DWI and signal intensity on T2WI in identifying residual and recurrent tumors in patients with treated head and neck cancer.6-9 Based on previous studies, tissues with diffusion facilitation and either low T2 signal intensity (SI) (less than or equal to muscles) that usually represents fibrotic tissue or high T2 SI (approaching the CSF signal), which usually represents edema and granulation, have no to low-level suspicion for malignancy.6,8 Studies examining the effectiveness of DWI in detecting locoregional tumor residual or recurrence (LTR) in the posttreatment neck consider that the histopathologic features of malignant tissues, such as increased cellularity and nuclear hyperchromatism, result in a diminution of intra- and extracellular spaces available for the diffusion of water protons with a consequent decrease in ADC values. This contrasts with the low cellularity with an increase in interstitial water associated with edema and inflammation, causing subsequent elevation of ADC values.7,10,11We hypothesized that tailoring NI-RADS criteria for MR imaging with DWI features and T2 SI may improve the diagnostic performance of the existing NI-RADS system for MR imaging surveillance.This study aimed to recommend new NI-RADS criteria for MR imaging surveillance based on the current system using DWI and T2 signals and to evaluate the diagnostic performance of integrating these criteria into the existing NI-RADS algorithm.  相似文献   
23.

Introduction  

Dyggve–Melchior–Clausen (DMC) syndrome is a rare autosomal recessive type of skeletal dysplasia. It is characterized by the association of progressive spondyloepimetaphyseal dysplasia (SEMD), microcephaly, mental retardation (MR), and coarse facies. The radiographic appearance of generalized platyspondyly with double-humped end plates and the lace-like appearance of iliac crests are pathognomonic and distinctive of DMC syndrome. The disorder results from mutations in the DYM gene mapped in the 18q12-12.1 chromosomal region.  相似文献   
24.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased.  相似文献   
25.
OBJECTIVES : To define the prevalence of cardiovascular risk factors and their relation to the level of blood pressure, in Egyptians. METHODS : Data were collected during the Egyptian National Hypertension project, a national hypertension survey in Egypt. During phase I of the survey, hypertensive (HT) patients were identified. In phase II, clinical and laboratory evaluations were made on HT and gender-matched normotensives (NT). A total of 2313 individuals were examined, 311 NT males, 443 NT females, 670 HT males and 889 HT females. RESULTS : The prevalence of obesity was 33 and 47% in hypertensive men and women, respectively. After adjusting for age, HT men had significantly higher heart rate, total cholesterol (TC), triglycerides (TG), fasting blood sugar (FBS), post-prandial blood sugar (PBS), body mass index and waist/hip (W/H) ratio than their NT counterparts. In addition, HT women had higher low-density lipoprotein cholesterol (LDL-C). The prevalence of elevated LDL-C and FBS increased with age. The prevalence of hypertriglyceridemia, elevated FBS and obesity rose with increasing level of blood pressure (BP). From the 25-34 to the 55-64 age group, the percentage of hypertensives with > or = 2 risk factors rose from 42.9 to 60.6% in men, and from 9.4 to 46.2% in women. All risk factors were more prevalent in urban populations. CONCLUSION : This is one of the few reports on the prevalence of cardiovascular risk factors in a developing country. Risk factors cluster with rising level of BP and with ageing. Obesity is very prevalent, particularly in hypertensive Egyptian women. Health efforts directed at the prevention and treatment of obesity should be a high priority.  相似文献   
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High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.  相似文献   
28.
Doxorubicin (Dox) is a potent anticancer agent; its clinical use is limited for its marked cardiotoxicity and nephrotoxicity. The present study investigated the possible protective effect of telmisartan, an angiotensin AT1-receptor blocker versus captopril, an angiotensin-converting enzyme inhibitor, on Dox-induced cardiotoxicity and nephrotoxicity in rats. Rats were allocated into four groups. Control group, Dox group, Dox + telmisartan group, and Dox + captopril group. Cardiotoxicity and nephrotoxicity were assessed biochemically and histopathologically. Frozen heart and kidney specimens were used for estimation of lipid peroxides product (MDA), reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and nitric oxide (NO). Expression of induced nitric oxide synthase (iNOS) was detected by immunohistochemistry. Coadministration of either telmisartan or captopril with Dox equally decreased the biochemical markers of both cardiotoxicity (LDH and CK–MP) and nephrotoxicity (urea and creatinine). Both telmisartan and captopril attenuated the effects of Dox on oxidative stress parameters and NO. Histopathologically, coadministration of either drug with Dox was able to attenuate Dox-induced myocardial fibrosis and renal tubular damage. Immunohistochemistry, expression of iNOS was increased in both cardiac and renal tissues. Both telmisartan and captopril significantly and equally attenuated the effect of Dox on all measured parameters. These results suggested that telmisartan has protective effects equal to that of captopril against Dox-induced cardiotoxicity and nephrotoxicity; implying that angiotensin II pathway plays a role in Dox-induced cardiac and renal damage. The protective effect of either drug relies, at least in part, on their antioxidant effects and decreased the expression of iNOS.  相似文献   
29.

Background  

Within the last decade there has been a growth in the call-centre industry in the UK, with a growing awareness of the voice as an important tool for successful communication. Occupational voice problems such as occupational dysphonia, in a business which relies on healthy, effective voice as the primary professional communication tool, may threaten working ability and occupational health and safety of workers. While previous studies of telephone call-agents have reported a range of voice symptoms and functional vocal health problems, there have been no studies investigating the use and impact of vocal performance in the communication industry within the UK. This study aims to address a significant gap in the evidence-base of occupational health and safety research. The objectives of the study are: 1. to investigate the work context and vocal communication demands for call-agents; 2. to evaluate call-agents' vocal health, awareness and performance; and 3. to identify key risks and training needs for employees and employers within call-centres.  相似文献   
30.
Intra-arterial thrombolysis is an alternative treatment to surgery for acute limb ischemia. We report our own experiences by retrospectively assessing initial and long-term outcomes using this strategy. Patients (n = 48; 50 events) underwent thrombolysis according to our protocol (64.6% male, median age 68.5 years). Using thrombolysis as an initial treatment strategy, overall limb survival on index admission was 84%. Of this group who had successful limb salvage, 76% was attributable to thrombolysis alone, and 24% had limb salvage attributable to subsequent surgery after failed thrombolysis or anticoagulation. Significant complications occurred in 8% of cases, and no deaths were attributed to thrombolysis. Patients alive at 6 and 24 months after index admission who had limb salvage attributable to thrombolysis alone had limb survival rates of 89% and 82%, respectively. The majority of these patients had not required subsequent secondary procedures to maintain limb survival. Thrombolysis is an acceptable and less invasive treatment of acute limb ischemia, with many patients not needing subsequent surgery.  相似文献   
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