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81.
In order to evaluate the morphologic types of appositional angle-closure glaucoma, biometric measurements were made in angle-closure glaucoma patients using Ultrasound biomicroscopy (UBM). Twenty-six patients with primary angle-closure glaucoma and 21 cataract patients with as a control group were examined. The angle-closure glaucomatous eyes were classified as type B in which the angle closure started at the bottom of the angle and type S in which the angle closure occurred in the vicinity of Schwalbe's line. The trabecular-ciliary process distance (TCPD, type B; 873.20+/-86.77 microm, type S; 832.52+/-82.96 microm, control; 1233.50+/-73.01 microm, p = 0.000) and the angle opening distance (AOD500, type B; 89.75+/-63.27 microm, type S; 88.85+/-72.95 microm, control; 304.40+/-104.30 microm, p = 0.000) were significantly shorter in patients with angle closure vice control group. No significant difference were noted in the three groups of patients in regards to iris thickness or ciliary process-iris angle. In this study, we have demonstrated that there are two types of appositional angle-closure and have shown the forward rotation of the ciliary process without changes of the ciliary process-iris angle in cases of angle-closure glaucoma.  相似文献   
82.
Oxidative stress has been implicated in the pathogenesis of different neurodegenerative disorders. To investigate the protective effects of Wuyaoshunqisan against H2O2-induced apoptosis in the central nervous system, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) method, flow cytometric analysis, and the DNA fragmentation assay were performed on cells of the hippocampal cell line HiB5. Through the morphological and biochemical analyses, it was shown that HiB5 cells treated with H2O2 exhibit classical apoptotic features, while the occurrence of such changes is reduced in cells pre-treated with Wuyaoshunqisan prior to H2O2 exposure.  相似文献   
83.
The Neuropathology Study Group of the Korean Society of Pathologists conducted a nationwide collection of central nervous system (CNS) tumors to evaluate the relative frequency in Korea of CNS tumors belonging to the revised World Health Organization (WHO) classification categories. A total of 3221 histologically proven cases of CNS tumors were collected from 13 institutes between 1997 and 1998. All the cases were classified according to the revised WHO histological types and analyzed for the relative frequency, the distribution of age and sex, and location of tumors. The most frequent type of CNS tumors in Korea was meningiomas, followed by pituitary adenoma, glioblastoma, astrocytoma, and schwannoma. Among the pediatric CNS tumors, pilocytic astrocytoma, medulloblastoma, craniopharyngioma, germ cell tumors, and ependymomas were common types of tumors. Compared with a previous nationwide study, the rates for neuronal/glial tumors, glioblastoma, malignant lymphoma, and cystic lesion were increased, and the rate of embryonal tumors was decreased. The overall male to female ratio was 0.9:1, which may be attributed to the greater number of female-predominate meningiomas and pituitary adenoma. Compared with Western countries, Koreans had higher rates of pituitary adenoma and meningiomas and lower rate of gliomas. The relative frequency of CNS tumors among Koreans is very similar to that reported in Taiwan. The occurrence rates for various subtypes of CNS tumors in Korea are distinct from those in the United States and Europe and similar in many ways to those in Asian and Mexican population.  相似文献   
84.
Abstract Heterotopic glial nodule in the lung is a rare abnormality. Most reported cases are associated with major cranial malformations including anencephaly. The pathogenesis of this condition has not been established. The hypotheses are (1) embolization of glial tissue after head trauma during fetal development, (2) aspiration/implantation of fragments of brain tissue from the amniotic fluid, and (3) aberrant migration of neural crest elements to the lung. This report documents the presence of an intravascular embolus of a glial nodule, which offers support to the embolization theory for the pathogenesis of this peculiar abnormality.  相似文献   
85.
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
86.
BACKGROUND: The purpose of this study was to analyze the prognostic factors affecting local control and survival rates for patients with early breast cancer who received breast conserving treatment (BCT) and to find out the optimal treatment according to their risk factors. METHODS: From October 1994 to December 2001, 605 patients with 611 stage I and II breast cancers received BCT, and the results were analyzed retrospectively. BCT consists of breast conserving surgery and whole breast irradiation. All the patients underwent lumpectomy or quadrantectomy. Axillary lymph node dissection or sentinel lymph node biopsy was performed in 608 cases (99.5%). The radiation dose to the whole breast was 50.4 Gy over 5 weeks with a 1.8 Gy daily fraction and with boost doses of 9-14.4 Gy administered to the tumor bed. Adjuvant chemotherapy was performed in most of the patients with axillary lymph node metastasis or tumors larger than 1 cm. The median follow-up period was 47 months. RESULTS: Local relapse, regional relapse and distant metastasis occurred in 15 (2.5%), 16 (2.6%) and 43 patients (7.1%), respectively. The 5-year overall survival, local-relapse-free survival, distant-metastasis-free survival and disease-free survival rates were 95.3%, 97.2%, 91.3% and 88.5%, respectively. On multivariate analysis, age (P = 0.02), number of involved axillary lymph nodes (P = 0.01) and nuclear grade (P = 0.01) affected the local-relapse-free survival. The factors associated with disease-free survival were the T stage (P = 0.05), number of involved axillary lymph nodes (P = 0.01) and nuclear grade (P = 0.001). Overall survival was associated with the T stage (P = 0.02), number of involved axillary lymph nodes (P = 0.01) and c-erb B2 overexpression (P = 0.05). Patients with more than two factors among (i) age 1 cm, (ii) positive lymph node metastasis and (iii) high nuclear grade showed an inferior 5-year disease-free survival rate compared with others (P = 0.0005). CONCLUSIONS: The most important prognostic factor affecting local control, disease-free survival and overall survival was axillary lymph node metastasis. The nuclear grade influenced local control and disease relapse. Patients with multiple unfavorable risk factors such as positive axillary lymph nodes, high nuclear grade, young age and large tumor showed poorer local control and disease-free survival than patients without any risk factors, and so more aggressive treatment is required for these patients.  相似文献   
87.
OBJECTIVE: The purpose of this study is to elucidate the usefulness of magnetic resonance imaging (MRI) and positron emission tomography (PET) for the detection of parametrial involvement and lymph node metastasis in patients with cervical cancer. METHODS: Thirty-six patients with cervical cancer were retrospectively enrolled. MRI and PET scans were performed for all patients within a week before radical surgery. The criterion for malignancy on MRI was >1 cm short axis diameter of the suspected lymph node. On PET, only fluorodeoxyglucose (FDG) uptake was significantly higher than the background and, if this FDG uptake showed on at least two consecutive axial slices, then the lesion was considered as a malignancy. We compared the extent of tumor on the surgical findings with the FIGO staging, MRI and PET scans. RESULTS: The accuracy of FIGO and MRI staging was 67 and 84.4%, respectively. The accuracy for detecting pelvic lymph node metastasis was better for PET than for MRI (78 versus 67%, respectively). All FDG uptake lymph nodes were confirmed as metastatic lymph nodes by pathological evaluation; this included five lymph nodes <1 cm in diameter. CONCLUSION: MRI provides an improved evaluation of local tumor extension, but PET is more useful for the evaluation of pelvic lymph nodes than MRI; however, PET still misses microscopic disease. Further studies are necessary to evaluate the usefulness of PET/computed tomography (CT) for the accuracy of the disease extension and the cost-effectiveness of MRI, PET or PET/CT in patients with cervical cancer.  相似文献   
88.
Bacterially expressed recombinant 10-kDa protein of Taenia solium metacestode (TsM) was previously found to be reliable in the diagnosis of active stage neurocysticercosis (NCC) by immunoblotting but not by ELISA. In this study, we evaluated the diagnostic feasibility of detecting eukaryote-expressed recombinant 10-kDa protein of TsM by ELISA (rTsM10-ELISA) in the serum and cerebrospinal fluid (CSF) from NCC patients. In 45 cases of active NCC, 91.1 and 97.8% cases showed positive reactions for serum and CSF by rTsM10-ELISA. ELISA employing the crude cyst fluid antigen (CF-ELISA) also revealed a similar result. Negligible cross-reactions were observed in serum samples from control subjects and from subjects with other helminthic diseases by rTsM10-ELISA (5/139 cases, 3.6%). By contrast, CF-ELISA demonstrated a high degree of cross-reactivity (24/139, 17.3%) especially from those patients with alveolar and cystic echinococcoses. The overall sensitivity and specificity of rTsM10-ELISA were 94.3 and 96.4%; and those of CF-ELISA were 95.7 and 84.5%, for serum and CSF, respectively. Antibody responses to rTsM10 were detected as early as 3 months after experimental infection of T. solium eggs in pigs. Our results show that ELISA with rTsM10 could be highly applicable in the serodiagnosis of NCC from early stage of infection.  相似文献   
89.
PURPOSE: A specially designed self-expandable covered metallic stent incorporated with beta-emitting radioisotope, Holmium-166 (Ho-166), was developed for delivering intraluminal brachytherapy as well as for internal bile drainage in malignant biliary stricture. The purpose of the study was to demonstrate the safety and tissue response of the radioactive metallic stent on the normal canine common bile duct (CBD) prior to the clinical application. MATERIALS AND METHODS: Nitinol self-expandable stents (diameter; 4 mm, length; 20 mm) were covered with polyurethane membrane (50 microm thick) containing 21 to 135 muCi of Ho-166 (mean, 77.9 microCi). To prevent migration of stent, the membrane covered only the middle 1 cm of the stent and the ends of the stent were left uncovered. The stents were placed in the CBD of 20 healthy beagle dogs. For control, non-radioactive covered stents were placed in another three dogs. The dogs were killed 3 to 6 months after stent insertion and histopathologic examination of CBD was performed. RESULTS: There was no stent migration in all cases. Varying degrees of papillary mucosal hyperplasia leading to significant narrowing of the lumen was observed within the lumen of the bare portion and under the mucosal surface of the non-radioactive covered stents. However, fibrosis was noted in Ho-166 coated area, instead of mucosal hyperplasia. Severity of fibrosis was correlated with estimated radiation dose. Despite high dose, there was no perforation of CBD wall. The membrane of Ho-166 coat was disrupted in some cases of 6 months follow-up. CONCLUSIONS: Holmium-166 incorporated covered stents demonstrated fibrosis of CBD wall and inhibition of ingrowth of mucosal hyperplasia without serious complication such as perforation, while control group showed severe mucosal hyperplasia.  相似文献   
90.
Abstract Background This study investigated the prevalence of alcohol use disorder in a Korean community and compared the results with 1984 epidemiological data. Method A sample of 1,059 residents aged 18–64 years was interviewed using the Korean version of the Composite International Diagnostic Interview (K-CIDI). The results obtained were compared with those of a 1984 epidemiological study. Results Lifetime prevalence of alcohol use disorder was 15.6% (abuse 6.8%, dependence 8.8 %) and 1-year prevalence 7.5% (abuse 2.5%,dependence 5 %).The male-to-female ratio of life-time prevalence was 5.8,which markedly decreased with decreasing age. A cohort effect, i. e. increases of lifetime prevalence in younger cohorts, was observed, with the exception of the 60- to 64-year-old cohort. The mean age of onset was 27.7 years (male 28.2 years, female 24.2 years). When the results of the present study were compared with those of the 1984 study, it was found that, during the past 15 years, lifetime prevalence has decreased, prevalence ratios of abuse and dependence have become reversed, and the male-to-female ratio has decreased. Conclusion Remarkable changes in the pattern of prevalence, which have occurred between 1984 and 1999, may be attributed to significant sociocultural changes and to a decrease in the proportion of a high-risk cohort in the populations.  相似文献   
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