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981.
This study investigated the global and regional effects of aging on brain volume, mean diffusivity (MD), and fractional anisotropy (FA) in 73 normal female subjects using voxel-based analysis. On a global scale, gray matter volume and FA were negatively correlated, whereas MD was positively correlated with age. Voxel-wise analyses showed brain volume and FA were negatively correlated predominantly in anterior structures, whereas MD was positively correlated in the cortical gray matter and periventricular white matter. Volume preservation was observed in the cingulate gyrus and subjacent white matter. FA increase was observed in the putamen. Voxel-based direct comparisons of volume and diffusion properties showed FA was more strongly negatively correlated in the fronto-temporal white matter, compared with volume and MD. Stronger positive correlation of MD was observed in the thalamus, caudate nucleus, and midbrain and stronger negative correlation of brain volume was observed in the frontal lobe and basal ganglia, compared with the other. These results indicate that diffusion properties and brain volume are complementary markers to the effects of aging.  相似文献   
982.
In this study, we tried to clarify the prevalence of suicidal ideation and self-mutilation including suicide attempts among patients with gender identity disorder (GID) and the relationship of those behaviors to demographic characteristics. A total of 500 consecutive Japanese GID patients without any other psychiatric comorbidity were evaluated at the outpatient GID Clinic of Okayama University Hospital. The lifetime rate of suicidal ideation was 72.0% of the total sample. There were no significant differences in the prevalence of suicidal ideation among groups divided by sex, age, age at onset or education. The lifetime prevalence of self-mutilation including suicide attempts was 31.8% of the total sample. Low level of education was significantly related to self-mutilation among both male-to-female and female-to-male GID patients. Younger age at onset was a significant factor affecting self-mutilation only among MTF GID patients. A lack of strategies to cope with severe distress among persons with lower education might induce a high frequency of self-mutilation including suicidal attempt. GID patients with a low level education might be at high risk of self-mutilation and should be watched with special attention to self-mutilation.  相似文献   
983.
Antiproliferative activities of fractions of Hypsizigus marmoreus were examined using HepG2 cells in vitro. The methanol extract of H. marmoreus markedly induced antiproliferative activity, and an active compound from this mushroom was identified as hypsiziprenol A9. Hypsiziprenol A9 inhibited cell proliferation in a time- and concentration-dependent manner by up to 80% on HepG2 cells by inducing arrest of the G1 phase. Further investigation revealed that hypsiziprenol A9 decreased expression of phosphorylated retinoblastoma protein (ppRb), cyclin D1, and cyclin E in a dose-dependent manner. These results suggest that hypsiziprenol A9 can inhibit the growth of HepG2 cells through inducing G1 phase cell cycle arrest due to the inhibition of pRb phosphorylation.  相似文献   
984.
p16, cyclin D1 and retinoblastoma protein (pRB) regulate G1 to S transition and are commonly targeted in various cancers. However, few studies have simultaneously examined all components of the p16/cyclin D1/pRB pathway (RB pathway) in hepatocellular carcinoma (HCC). To clarify the role of the disruption of the RB pathway in HCC, we analyzed p16, pRB and cyclin D1 in 47 HCCs. Inactivation of p16 was detected in 30 of 47 HCCs (64%) by Western blot analysis and significantly correlated with hypermethylation of the promoter of this gene. pRB expression was found to be absent in 13 of 47 HCCs (28%) by immunohistochemistry. We found that 38 of 47 HCCs (81%) contained at least one inactivation in either pRB or p16. Furthermore, there was a significant inverse correlation between p16 and pRB inactivation (p = 0.041). Overexpression of cyclin D1 was detected in 5 of 47 HCCs (11%) by immunohistochemistry. The cases with cyclin D1 overexpression exhibited an advanced clinicopathological appearance and also contained inactivation of pRB and/or p16. These findings suggest that inactivation of pRB and/or p16 is a major event in human hepatocarcinogenesis, while cyclin D1 overexpression may confer additional growth advantages to the tumor in addition to pRB and/or p16 inactivation in HCC.  相似文献   
985.
Neuropilin-1 on hematopoietic cells as a source of vascular development   总被引:8,自引:2,他引:8  
Yamada Y  Oike Y  Ogawa H  Ito Y  Fujisawa H  Suda T  Takakura N 《Blood》2003,101(5):1801-1809
Neuropilin-1 (NP-1) is a receptor for vascular endothelial growth factor-165 (VEGF165) and acts as a coreceptor that enhances the function of VEGF165 through VEGF receptor-2 (VEGFR-2). Studies using transgenic and knock-out mice of NP-1 indicated that this molecule is important for vascular development as well as neuronal development. We recently reported that clustered soluble NP-1 phosphorylates VEGFR-2 on endothelial cells with a low dose of VEGF165 and rescues the defective vascularity of the NP-1-/- embryo in vitro and in vivo. Here we show that NP-1 is expressed by CD45+ hematopoietic cells in the fetal liver, can bind VEGF165, and phosphorylates VEGFR-2 on endothelial cells. CD45+NP-1+ cells rescued the defective vasculogenesis and angiogenesis in the NP-1-/- P-Sp (para-aortic splanchnopleural mesodermal region) culture, although CD45+NP-1- cells did not. Moreover, CD45+NP-1+ cells together with VEGF165 induced angiogenesis in an in vivo Matrigel assay and cornea neovascularization assay. The extracellular domain of NP-1 consists of "a," "b," and "c" domains, and it is known that the "a" and "c" domains are necessary for dimerization of NP-1. We found that both the "a" and "c" domains are essential for such rescue of defective vascularities in the NP-1 mutant. These results suggest that NP-1 enhances vasculogenesis and angiogenesis exogenously and that dimerization of NP-1 is important for enhancing vascular development. In NP-1-/- embryos, vascular sprouting is impaired at the central nervous system (CNS) and pericardium where VEGF is not abundant, indicating that NP-1-expressing cells are required for normal vascular development.  相似文献   
986.
[Purpose] This study evaluated effects of a high-intensity linear polarized near-infrared ray irradiation for mitigation of muscle hypertonia. [Subjects] The subjects were 20 patients with cerebrovascular disease. [Methods] Subjects were randomly allocated to an intervention or control group. The intervention group received irradiation of the triceps surae. Passive range of motion and passive resistive joint torque of ankle dorsiflexion were measured before and after the intervention in knee extended and flexed positions. [Results] In the knee extended position, the mean changes in passive range of motion were 2.70° and −0.50° in the intervention and control groups, respectively, and the mean changes in passive resistive joint torque were −1.42 and −0.26 N·m in the intervention and control groups, respectively. In the knee flexed position, the mean changes in passive range of motion were 3.70° and 0.70° in the intervention and control groups, respectively, and the mean changes in passive resistive joint torque were −2.38 and −0.31 N·m in the intervention and control groups, respectively. In both knee positions, the mean changes in the two indices were greater in the intervention group than in the control group. [Conclusion] High-intensity linear polarized near-infrared ray irradiation increases passive range of motion and decreases passive resistive joint torque.Key words: Infrared ray, Muscle tone, Cerebrovascular disease  相似文献   
987.
PURPOSE: Anhydrobiotic organisms are known to have an extremely high tolerance against a range of stresses. However, the functional role of anhydrobiosis in radiation tolerance is poorly understood, especially in development following irradiation. The present study aims to evaluate effects of anhydrobiosis on radiation tolerance in an anhydrobiotic insect, Polypedilum vanderplanki. MATERIALS AND METHODS: Larval survival (48 h), anhydrobiotic ability, metamorphosis and reproduction after exposure to 1-9000 Gy of gamma-rays at the larval stage were compared between anhydrobiotic (dry) and normal (wet) phases. RESULTS: Wet larvae were killed in a dose-dependent manner at doses higher than 2000 Gy, and all died within 8 h after 4000 Gy exposure. In contrast, dry larvae survived even 5000 Gy, and some of them still tolerated 7000 Gy and were alive at 48 h after rehydration. Moreover, greater radiotolerance of dry larva, compared to wet ones, was demonstrated in terms of metamorphoses. However, anhydrobiosis did not protect against radiation damage in terms of producing viable offspring. CONCLUSION: These results indicate that anhydrobiosis enhances radiotolerance, resulting in increases of successful metamorphoses.  相似文献   
988.
Modifying potentials of various chemicals on tumor development were investigated in a wide-spectrum organ carcinogenesis model using male F344/DuCrj rats. The animals were treated with N-nitroso-diethylamine (100 mg/kg body weight, ip, single injection at the commencement of the study), N-methyl-N-nitrosourea (20 mg/kg body weight, ip, 4 times during weeks 1 and 2) and N-bis(2-hydroxypropyl)nitrosamine (0.1% in drinking water, during weeks 3 and 4) for multi-organ initiation and then were given one of 14 test chemicals including 6 hepatocarcinogens, 7 non-hepatocarcinogens and 1 non-carcinogen, or basal diet for 16 weeks. All rats were killed at the end of week 20, and the major organs were carefully examined for preneoplastic and neoplastic lesions. Immunohistochemical demonstration of glutathione S -transferase-positivc foci was also used for quantitative assessment of liver preneoplastic lesion development. Modifying effects were shown for 11 out of 14 test agents in the liver, forestomach, glandular stomach, lung, urinary bladder or thyroid, 7 of them targeting more than two organs. This was the first demonstration to our knowledge that cloflbrate possesses enhancing potential for urinary bladder carcinogenesis and an inhibiting effect on thyroid carcinogenesis. Caprolactam showed no effect in any organ, in agreement with its established inactivity. The results indicated that the system could be reliably applied as a medium-term multiple organ bioassay for assessment of the modification potential of test agents in unknown target sites.  相似文献   
989.
We report a rare case of an epidermoid cyst originating from an intrapancreatic accessory spleen, in a 40-year-old Japanese man with no clinical symptoms. A cystic tumor in the pancreatic tail was detected incidentally by abdominal ultrasonography. The patient was referred to the KKR Tachikawa Hospital for further examination of the tumor. Preoperative imaging findings suggested that the tumor was an epidermoid cyst originating from an intrapancreatic accessory spleen. On both pre-and post-contrast computed tomography and magnetic resonance images, the solid compartment of the tumor had the same X-ray attenuation and intensity as the spleen. Upon surgical excision, the mass consisted of solid and cystic components that were macroscopically evident on the preoperative images. Microscopic analysis revealed that the solid component was an accessory spleen in the pancreatic tail, whereas the cystic component was lined with stratified epithelium representative of an epidermoid cyst. This is the thirteenth report (in English) of an epidermoid cyst originating from an intrapancreatic accessory spleen, and the first case to be diagnosed prior to surgery.  相似文献   
990.
A 70-year-old man who had worked in a stonepit for about fifty years was admitted to our hospital for detailed examination of the signs of pneumoconiosis (3/3, q) and a nodular shadow in the right upper lung field. Under a clinical diagnosis of lung cancer complicated with pneumoconiosis, right upper lobectomy with a right S6 resection was performed. Pathological examination revealed moderately differentiated adenocarcinoma of the right S2, well-differentiated adenocarcinoma of the right S6, and a squamous cell carcinoma of the right S1 which was not detected by chest CT. In addition to the difficulty of diagnosing lung cancer in a patient with severe pneumoconiosis, treatment for lung cancer may be limited by the poor pulmonary function that results from pneumoconiosis. Although the labor administration's decision that lung cancer patients with concomitant pneumoconiosis deserve compensation can be evaluated as a good one, the study of the relationship between pneumoconiosis and lung cancer needs further study through follow-up examination of pneumoconiosis cases.  相似文献   
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