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11.
Yong Jun Choi Chang-Hwa Kim Jaeuk Lee Min Kwang Byun Jae Hwa Cho Hye Jung Park 《Yonsei medical journal》2022,63(7):603
PurposeCurrently, there are multiple options for the pharmacological treatment of asthma. This study aimed to compare the effects of different asthma medications on exacerbation in a real-world setting.Materials and MethodsWe retrospectively reviewed electronic medical records of asthma patients who visited the hospital from November 1, 2016 to October 31, 2019. The number of asthma exacerbations requiring administration of systemic steroids was the primary outcome. A time-varying Cox regression analysis was used to reflect the real-world setting: variable usage times, discontinuation, and switching of medication.ResultsAmong 937 patients with asthma, 228 (24.3%) experienced asthma exacerbation during the study period. Asthma exacerbation was observed in patients using short-acting β2-agonists (SABA) alone (50.4% vs. 28.6%, p<0.001) as well as in patients not using inhaled corticosteroids (ICS) (58.8% vs. 40.3%, p<0.001), long-acting β2-agonists (LABA) (54.8% vs. 36.1%, p<0.001), and leukotriene receptor antagonists (71.5% vs. 50.8%, p<0.001). A time-varying Cox regression analysis of asthma exacerbations according to the duration of asthma medication showed that SABA alone increased the risk of asthma exacerbation [hazard ratio (HR), 1.834; 95% confidence interval (CI), 1.299–2.588; p=0.001], whereas ICS-LABA decreased the risk (HR, 0.733; 95% CI, 0.538–0.997; p=0.048). However, in the subgroup analysis according to medication type, specific ingredients showed no significant differences.ConclusionIn the real world, asthma medications affect asthma exacerbation variably according to the medication type. 相似文献
12.
The findings of ruptured hepatocellular carcinoma on helical CT. 总被引:7,自引:0,他引:7
B G Choi S H Park J Y Byun S E Jung K H Choi J Y Han 《The British journal of radiology》2001,74(878):142-146
To evaluate the helical CT findings of ruptured hepatocellular carcinoma (HCC), 12 patients with ruptured HCC were reviewed with regard to the tumour's location, size and contour protrusion, the appearance of the mass, the enhancement pattern, multiplicity and secondary changes. All ruptured tumours were located at the periphery of the liver and had a protruding contour. The maximum diameter of tumours ranged from 2 cm to 16 cm. Discontinuity of the hepatic surface was seen in 11 cases. In eight cases, CT images during the arterial phase showed a non-enhancing low attenuating lesion with focal discontinuity and peripheral rim enhancement. Seven cases showed separation of tumour content from the peripheral enhancing rim and intraperitoneal rupture of tumour content into the perihepatic space. Because of the similar appearance to an enucleated orbital globe with remaining sclera, this was termed the "enucleation sign". As well as ruptured masses, 10 cases with non-ruptured masses also showed a non-enhancing low attenuating pattern. Seven cases showed a haematoma with high attenuation around the ruptured mass. The peripheral location, protruding contour, discontinuity of the hepatic surface and surrounding haematoma are helpful signs in the diagnosis of ruptured HCC. The "enucleation sign" may be a characteristic finding in ruptured HCC. 相似文献
13.
14.
Introduction Aneurysms of the posterior cerebral artery (PCA) are rare, and most of the studies reported in the literature in which the
endovascular approach was applied were carried out on a limited number of patients with PCA aneurysms. We retrospectively
reviewed our cases of PCA aneurysms – at various locations and of differing shapes – that received endovascular treatment
and evaluated the treatment outcome.
Methods From January 1996 to December 2006, 13 patients (eight females and five males) with 17 PCA aneurysms (nine fusiform and eight
saccular) were treated using the endovascular approach. The age of the patients ranged from 20 to 67 years, with a mean age
of 44 years. Of the 13 patients, ten presented with intracranial hemorrhage, and one patient, with a large P2 aneurysm, presented
with trigeminal neuralgia; the aneurysms were asymptomatic in the remaining two patients.
Results All 13 patients were successfully treated, with only one procedure-related symptomatic complication. Seven patients were treated
by occlusion of the aneurysm and parent artery together; five patients, by selective embolization of the aneurysm; one patient,
by partial coiling. Although infarctions were found in two patients treated with selective embolization and in three patients
treated with parent artery occlusion, only one patient with a ruptured P2 aneurysm treated with parent artery occlusion developed
transient amnesia as an ischemic symptom.
Conclusion Posterior cerebral artery aneurysms can be treated safely with either occlusion of the aneurysm together with the PCA or with
a selective coil embolization. Infarctions may occur after endovascular treatment, but they are rarely the cause of a disabling
symptom. 相似文献
15.
Objective To evaluate the efficacy of F-18-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG PET/CT) in differentiating malignant from benign pathologic
fractures.
Materials and methods F-18 FDG PET/CT was performed on 34 patients with pathologic fractures between May 2004 and June 2007. Fractures were located
in tubular bones (26), in the pelvis (six), in the spine (one) and in a rib (one). The FDG uptake pattern at the fracture
site was described, whether FDG uptake occurred in the marrow or cortex and soft tissue. Maximum standardized uptake values
(SUVmax, the largest value at the region of interest) were measured at the fracture site, including cortical bone, bone marrow
and soft tissue. As a reference standard, biopsy was used for 12 patients and clinical follow-up for 22 patients. Sensitivity,
specificity and diagnostic accuracy of PET/CT were calculated.
Results There were 19 malignant and 15 benign fractures. In the malignant fractures, PET/CT demonstrated high (mean SUVmax 12.0, range
4.3 to 45.7) F-18 FDG uptake in bone marrow in most cases (17 of 19). In benign fractures, there was low FDG uptake (mean
SUVmax 2.9, range 0.6 to 5.5) within cortical bone or adjacent soft tissue around the fracture, rarely in the marrow. There
were significant differences in the pattern of intramedullary FDG uptake (P < 0.001) and in the mean SUVmax (P < 0.01) between malignant and benign fractures. The sensitivity, specificity and diagnostic accuracy of F-18 FDG PET/CT were
89.5%, 86.7% and 88.2%, respectively, with a cut-off SUVmax set at 4.7. The time interval between fracture and PET/CT did
not significantly influence FDG uptake at the fracture site.
Conclusion F-18 FDG PET/CT reliably differentiated between malignant and benign fractures based on the SUVmax and based on medullary
uptake, which was characteristic for malignant fractures.
This research was supported by the Yeungnam University research grants in 2007. 相似文献
16.
Phenotypic expression of renal diseases encompasses a complex interaction between genetic, environmental, and local tissue factors. The level of complexity requires integrated understanding of perturbations in the network of genes, proteins, and metabolites. Metabolomics attempts to systematically identify and quantitate metabolites from biological samples. The small molecules represent the end result of complexity of biological processes in a given cell, tissue, or organ, and thus form attractive candidates to understand disease phenotypes. Metabolites represent a diverse group of low-molecular-weight structures including lipids, amino acids, peptides, nucleic acids, and organic acids, which makes comprehensive analysis a difficult analytical challenge. The recent rapid development of a variety of analytical platforms based on mass spectrometry and nuclear magnetic resonance have enabled separation, characterization, detection, and quantification of such chemically diverse structures. Continued development of bioinformatics and analytical strategies will accelerate widespread use and integration of metabolomics into systems biology. Here, we will discuss analytical and bioinformatic techniques and highlight recent studies that use metabolomics in understanding pathophysiology of disease processes. 相似文献
17.
MRI of primary meningeal tumours in children 总被引:5,自引:0,他引:5
H.-K. Yoon S. S. Kim I. O. Kim D. G. Na H. S. Byun H. J. Shin B. K. Han 《Neuroradiology》1999,41(7):512-516
Childhood meningeal tumours are uncommon and mostly meningiomas. We reviewed the histological and radiological findings in
meningeal tumours in six children aged 12 years or less (four benign meningiomas, one malignant meningioma and one haemangiopericytoma).
Compared to the adult counterpart, childhood meningiomas showed atypical features: cysts, haemorrhage, aggressiveness and
unusual location. MRI features varied according to the site of the tumour, histology, haemorrhage, and presence of intra-
or peritumoral cysts. Diagnosis of the extra-axial tumour was relatively easy in two patients with meningiomas, one malignant
meningioma and one haemangiopericytoma. MRI findings strongly suggested an intra-axial tumour in two patients with benign
meningiomas, because of severe adjacent edema. Awareness of the variable findings of childhood meningiomas and similar tumours
may help in differentiation from brain tumours.
Received: 22 September 1998 Accepted: 18 November 1998 相似文献
18.
CT features of systemic lupus erythematosus in patients with acute abdominal pain: emphasis on ischemic bowel disease 总被引:13,自引:0,他引:13
Byun JY Ha HK Yu SY Min JK Park SH Kim HY Chun KA Choi KH Ko BH Shinn KS 《Radiology》1999,211(1):203-209
PURPOSE: To evaluate the computed tomographic (CT) features of systemic lupus erythematosus (SLE) in patients with acute abdominal pain. Special emphasis was placed on the analysis of ischemic bowel disease. MATERIALS AND METHODS: The authors retrospectively reviewed the images from 39 abdominal CT examinations performed in 33 patients with SLE and acute abdominal pain. Images were evaluated for bowel wall changes, mesenteric changes, fluid collection, retroperitoneal lymphadenopathy, peritoneal enhancement, and hepatomegaly as well as for changes in other abdominal organs. Ischemic bowel disease was diagnosed if at least three of the following signs were seen: bowel wall thickening, target sign, dilatation of intestinal segments, engorgement of mesenteric vessels, and increased attenuation of mesenteric fat. RESULTS: Thirty-one (79%) of the 39 examinations had CT findings diagnostic of ischemic bowel disease, including symmetric bowel wall thickening (n = 29), target sign (n = 26), and mesenteric vascular engorgement and haziness (n = 31). In 24 cases, bowel wall thickening was multifocal, with variable length, and did not appear to be confined to a single vascular territory. CONCLUSION: The most common CT finding in patients with SLE and acute abdominal pain is ischemic bowel disease. CT is useful for detecting the primary cause of gastrointestinal symptoms, planning treatment, and monitoring for infarction or perforation. 相似文献
19.
CT and MR imaging features of adnexal torsion. 总被引:15,自引:0,他引:15
Sung E Rha Jae Y Byun Seung E Jung Jung I Jung Byung G Choi Bum S Kim Hyun Kim Jae M Lee 《Radiographics》2002,22(2):283-294
In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment. 相似文献
20.
Byun CS Park IK Kim H Yu W 《The Korean journal of thoracic and cardiovascular surgery》2012,45(2):131-133
A 31-year-old female was referred from other hospital due to migrating chest pain, mild cough, and blood-tinged sputum for three days before admission. Laboratory tests were unremarkable. Chest computed tomography revealed an elliptical necrotic mass at the left anterior mediastinum, measuring 7×3×4 cm. With the impression of mediastinal abscess or loculated empyema, thoracoscopic resection was performed. There was severe pleural adhesion around the mass. The mass could be resected by the wedge resection of the adhesed upper lobe tissue of left lung around the mass. Final pathologic diagnosis was ectopic pancreas. 相似文献