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91.
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   
92.
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   
93.
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   
94.
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   
95.
Scores of the performance scale of the Wechsler Adult Intelligence Scale (WAIS) declined linearly with age from the 6th decade, whereas those of the verbal scale did not. This decrease in performance intelligence was thought to be related to an age-related frontal atrophy. The relationship between scores of the WAIS and changes in regional cortical gray matter density were examined in healthy elderly subjects using voxel-based morphometry. Thirty healthy non-demented individuals >50 years of age were tested with the WAIS and scanned with brain magnetic resonance imaging (MRI). The right neocerebellum was significantly associated with scores of the performance intelligence scale while frontal lobes were not. The current study suggests that the cerebellum may play an important role in changes of intellectual capacity in old age.  相似文献   
96.
Our previous studies indicated that Alzheimer's disease (AD) related amyloid beta peptide (Abeta) significantly altered muscarinic cholinergic receptor (mChR) signaling on the level of G protein regulated phospholipase C (PLC) leading to the lower formation of inositol-1,4,5-triphosphate (IP3) and diacylglycerol (DAG). Recent studies indicated that poly (ADP-ribose) polymerase-1 (PARP-1) is a new nuclear target in signal transduction pathway in the brain. In this study the effect of Abeta 25-35 (25 microM) and non-Abeta component of Alzheimer's disease amyloid (NAC, 10 microM) on mChR-dependent signaling to PARP-1 was determined. PARP-1 activity was estimated radiochemically using egzogenous substrate adenine[14C]NAD. The results showed that the non hydrolysable agonist of mChR, carbachol (1 mM) together with GTP(g)S (100 microM) stimulated PARP-1 activity in the hippocampus by about 100%. TMB-8, inhibitor of IP3 receptor decreased PARP-1 activation evoked by carbachol/GTP(g)S. Stimulation of mChR did not lead to free radicals generation but activate PARP-1 through IP3/Ca2+ regulated processes. This cholinergic receptor dependent PARP-1 activation was abolished by Abeta and NAC peptide. These toxic peptides themselves significantly stimulated PARP-1 activity by free radicals mediated DNA damage. These data indicated that Abeta and NAC peptide affected mChR-dependent signal transduction to PARP-1 probably through free radicals evoked inhibition of IP3 formation by phospholipase C.  相似文献   
97.
Kim TS  Sun K  Lee KB  Lee HW  Baek KJ  Park SY  Son HS  Kim KT  Kim HM 《Artificial organs》2004,28(12):1106-1109
Nonpulsatile blood pumps are mainly used in extracorporeal life support systems. Although pulsating blood flow is known to be physiological, a pulsatile pump is not commonly applied in a circuit with a membrane oxygenator because of damage to the blood cells. The hypothesis that the placement of a pressure-relieving compliance chamber in a circuit might reduce blood cell trauma was tested. An extracorporeal life support circuit was constructed in an acute lung injury model of dogs by oleic acid infusion. The animals were divided into three groups. In group I (n = 6) a nonpulsatile centrifugal pump was used as a control. In group II (n = 4) a single-pulsatile pump was used, and in group III (n = 6) a single-pulsatile pump equipped with a compliance chamber was used. Pump flow was maintained at 1.8-2.0 L/min for 2 h. Hemodynamics and blood gas analyses indicated that the pulsatile groups II and III had better results than the nonpulsatile group I. The plasma-free hemoglobin level, which indicates blood cell trauma, was the lowest in group I and the highest in group II but was significantly decreased in group III. A pressure-relieving compliance chamber could significantly reduce high circuit pressures and blood cell trauma.  相似文献   
98.
PURPOSE: To evaluate the efficacy of percutaneous image-guided sclerotherapy of lymphangiomas with use of acetic acid. MATERIALS AND METHODS: Twelve patients with lymphangiomas were treated with acetic acid as the sclerosant. There were eight male patients and four female patients, ranging in age from 1 to 29 years (mean, 11 years). The lymphangiomas were located at the neck (n = 5), upper extremity (n = 3), axilla (n = 1), cervicomediastinum (n = 1), anterior chest wall (n = 1), and retroperitoneum (n = 1). Two patients had recurrent lymphangiomas after surgery and two patients had undergone failed sclerotherapy with another sclerosant. The acetic acid used as the sclerosant was 40%-50% in concentration, and the amounts used ranged from 2 mL to 70 mL (mean, 11.3 mL), which was equivalent to 4.6%-50% (mean, 30.6%) of the aspirated lymphatics. All procedures were performed under ultrasonographic and fluoroscopic guidance. The sclerosant was removed after sclerotherapy. All patients except one underwent one treatment session. RESULTS: Complete resolution of the lymphangioma was achieved in eight patients (66.7%), good resolution (>50% reduction) was achieved in three (25.0%), and poor resolution (<50% reduction) was seen in one (8.3%). Complications encountered included pneumonitis adjacent to the lymphangioma (n = 1), pain (n = 2), hematuria (n = 1), and tingling sensation in the forearm (n = 1). CONCLUSION: Percutaneous sclerotherapy of the lymphangiomas with use of acetic acid is an effective method without serious complications.  相似文献   
99.
The camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is characterized by congenital or early-onset camptodactyly, childhood-onset noninflammatory arthropathy associated with synovial hyperplasia. Some patients have progressive coxa vara deformity and/or noninflammatory pericardial effusion. CACP is inherited as an autosomal recessive mode and the disease gene is assigned to a 1.9-cM interval on human chromosome 1q25-31. We describe a 10-yr-old boy who has typical features of CACP without familial association.  相似文献   
100.
Lee DW  Cho JH  Phee YG  Yu IJ 《Industrial health》2004,42(2):99-110
In response to new information about the health risk of chemical and concern expressed by academia, labor, and industry, chemical regulatory framework under Industrial Safety and Health Act was completely restructured in Year 2003 to be more systematic and to meet the particular needs in Korea. The history and the current status of chemical regulatory framework in the Republic of Korea are reviewed.  相似文献   
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