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51.
PURPOSE: A sixth annual survey was carried out by mail in January 1998, to investigate the current trends in cataract and refractive surgery in Japan. RESPONDENTS: Questionnaires were sent to 816 ophthalmologist members of the Japanese Society of Cataract and Refractive Surgery. Data received from 409 (50.1%) of the recipients were cross-analyzed and compared with those from the previous surveys. RESULTS AND CONCLUSION: In cataract surgery, there have been trends toward more surgical procedures performed by a surgeon, shorter period of hospitalization, and increased number of outpatient surgery. Ninety-two percent of respondents preferred phacoemulsification, 54% used the self-sealing wound-closure technique, and 19% used topical anesthesia for phacoemulsification. As for refractive surgery, surgeons remained rather conservative; with 28% and 7% of surgeons doing astigmatic keratotomy and refractive keratotomy, respectively. Photorefractive keratectomy, laser in situ keratomileusis, and phakic intraocular lens were judged to be useful refractive surgical procedures by 56.6%, 43.3%, and 25.1% of the respondents, respectively.  相似文献   
52.
This study aimed to examine whether K+ loading or Na+ loading augments renal kallikrein (KK) secretion. It also investigated the effect of blockade of renal ATP-sensitive K+ channels on renal KK secretion. Rats were administered 50 mmol/kg body weight of KCl. Twelve-hour collected urine was measured for urinary excretion of K+ and Na+ and urinary activity of renal KK. Increases in urinary excretion of K+ and Na+ by K+ loading accompanied an increase in renal KK secretion. In another experiment, rats were infused intravenously with a solution of 75 mM K+ and 75 mM Na+, 150 mM Na+ or 300 mM Na+ for 150 min under anesthesia. Urinary KK activity was measured in urine collected every 30 min. Renal KK secretion began to increase within the 30 min infusion of K+ solution and persisted at more elevated levels during the infusion with K+ solution than with Na+ solutions. Furthermore, rats were given intravenous injection of ATP-sensitive K+ channel blocker, either PNU-37883A (4-morpholinecarboximidine-N-1-adamantyl-N'-cyclohexyl) at a concentration of 10 mg/kg or glibenclamide at 30 mg/kg. Renal KK secretion increased 30 min after administration of both PNU-37883A and glibenclamide. In conclusion, it may be that augmentation of renal KK secretion by K+ loading occurred through an increase in urinary K+ excretion followed by the inhibition of K+ transport from ATP-sensitive K+ channels.  相似文献   
53.
Summary We compared the potential of asbestos and man-made fibers to attack DNA by the determination of the yield of 8-hydroxy-2-deoxyguanosine (8-OH-dGuo) under several in vitro conditions. Asbestos induced 6.6–99.8 of 8-OH-dGuo per 105 dGuo in calf thymus DNA after 20 h of incubation, while the levels of 8-OH-dGuo in man-made fibers were low (3.6–9.4). The amounts of 8-OH-dGuo were strongly stimulated by the addition of H2O2 in asbestos, but not in man-made fibers. However, the yield of 8-OH-dGuo was induced more than that with asbestos by the further addition of FeSO4 in attapulgite, fiberglass, potassium titanate whisker, and metaphosphate polymer. The addition of ethylene diamine tetraacetic acid (EDTA) promoted the induction of 8-OH-dGuo with asbestos and H2O2. The effects of mannitol (known as a hydroxy radical scavenger) were not dramatic on 8-OH-dGuo induction by all fibers except fiberglass and basic magnesium sulfate whisker, which induced higher amounts after mannitol addition than in these fibers and H2O2. Therefore, it was suggested that asbestos could damage DNA, resulting in 8-OH-dGuo as a cause of point mutation, and also several types of manmade fibers had similar effects to asbestos under certain conditions.  相似文献   
54.
We have reported that excess soybean treatment and iodine deficiency synergistically interact, resulting in remarkable induction of thyroid hyperplasias in rats. In the present study, modifying effects of excess soybean and iodine-deficient diets were investigated in the post-initiation phase of N-bis(2-hydroxypropyl)nitrosamine [DHPN]-initiated thyroid tumorigenesis in rats. AIN-93G in which casein was replaced with gluten was used as a basal diet to avoid possible iodine contamination. In Experiment 1, F-344 rats of both sexes were sc injected with DHPN at a dose of 2800 mg/kg body weight and then fed a diet containing 0%, 0.8%, 4%, or 20% defatted soybean for 12 weeks, with proportional replacement of gluten by soybean flour. Although no thyroid proliferative lesions were found in any group, the absolute thyroid weights were significantly (p < 0.01) elevated with the 20% soybean treatment. In Experiment 2, after similar sc injection of DHPN, rats were fed a basal diet or a diet containing 20% soybean under iodine normal or deficient conditions for 12 weeks. Soybean feeding to both sexes under iodine deficient but not normal conditions dramatically enhanced the development of thyroid follicular adenomas (p < 0.01) and adenocarcinomas (p < 0.05), in good agreement with decrease in thyroxine and increase in thyroid-stimulating hormone. Thus co-exposure to excess soybean and iodine deficiency results in synergistic promotion of DHPN-initiated thyroid tumorigenesis in rats, of which mechanisms appear to primarily involve effects on serum hormone levels.  相似文献   
55.
Label-free metabolic imaging of non-alcoholic fatty liver disease (NAFLD) mouse liver is demonstrated ex vivo by dynamic optical coherence tomography (OCT). The NAFLD mouse is a methionine choline-deficient (MCD)-diet model, and two mice fed the MCD diet for 1 and 2 weeks are involved in addition to a normal-diet mouse. The dynamic OCT is based on repeating raster scan and logarithmic intensity variance (LIV) analysis that enables volumetric metabolic imaging with a standard-speed (50,000 A-lines/s) OCT system. Metabolic domains associated with lipid droplet accumulation and inflammation are clearly visualized three-dimensionally. Particularly, the normal-diet liver exhibits highly metabolic vessel-like structures of peri-vascular hepatic zones. The 1-week MCD-diet liver shows ring-shaped highly metabolic structures formed with lipid droplets. The 2-week MCD-diet liver exhibits fragmented vessel-like structures associated with inflammation. These results imply that volumetric LIV imaging is useful for visualizing and assessing NAFLD abnormalities.  相似文献   
56.
Unrelated cord blood transplantation (CBT) is an alternative curative option for adult patients with acute myeloid leukemia (AML) who need allogeneic hematopoietic cell transplantation (HCT) but lack an HLA-matched related or unrelated donor. However, large-scale data are lacking on CBT outcomes for unselected adult AML. To investigate the trends of survival and engraftment after CBT over the past 22 years, we retrospectively evaluated the data of patients with AML in Japan according to the time period of CBT (1998–2007 vs 2008–2013 vs 2014–2019). A total of 5504 patients who received single-unit CBT as first allogeneic HCT for AML were included. Overall survival (OS) at 2 years significantly improved over time. The improved OS among patients in ≥ complete remission (CR)3 and active disease at CBT was mainly due to a reduction of relapse-related mortality, whereas among patients in first or second CR at CBT, this was due mainly to a reduction of non-relapse mortality. The trends of neutrophil engraftment also improved over time. This experience demonstrated that the survival and engraftment rate after CBT for this group has improved over the past 22 years.Subject terms: Acute myeloid leukaemia, Cancer immunotherapy  相似文献   
57.
Background: Although more children with cancer continue to be cured, these survivors experience various late effects. Details of the medical visit behaviors of childhood cancer survivors (CCS) in adulthood remain to be elucidated. Methods: In order to examine medical visits in the past and future of CCS, we performed a cross‐sectional survey with self‐rating questionnaires on medical visits of CCS compared with control groups (their siblings and the general population). Results: Questionnaires were completed by 185 CCS, 72 of their siblings and 1000 subjects from the general population and the results were analyzed. Mean ages at this survey and the duration after therapy completions of CCS were 23 and 12 years, respectively. We found that the previous treatment hospitals (where CCS were treated for their cancer) were the most commonly visited medical facilities for the CCS group (74% for female patients and 64% for male patients) and more than half of the CCS preferred to continue visiting the previous treatment hospital with enough satisfaction in Japan. The multivariate analysis showed that female sex and relapse were significantly associated with the past visits to the previous treatment hospital and that the CCS with brain tumors or bone/soft tissue sarcomas and CCS with any late effects tended to continue the relationships with the hospital. In addition female sex was also significantly associated with desired future visits to the previous treatment hospital. On the other hand, the married CCS tended to be disinclined to visit the hospital it in the future. Conclusions: In order to optimize risk‐based care and promote health for CCS after adulthood, we should discuss the medical transition with CCS and their parents.  相似文献   
58.
  目的  探讨细胞表面抗原4F2重链(4F2 heavy chain, 4F2hc)在人脑胶质瘤组织中的表达水平及其与胶质瘤病理学特征、细胞增殖以及血管形成的关系。  方法  采用免疫组化方法检测4F2hc、Ki-67和CD34在62例人脑胶质瘤组织中的表达, 计数Ki-67标记指数(Ki-67 LI)和微血管密度(MVD)。  结果  4F2hc在胶质瘤中高表达, 其免疫阳性染色既定位于瘤细胞也定位于血管内皮; 4F2hc表达随胶质瘤病理级别升高而明显增强(P=0.001), 在高度恶性胶质瘤中4F2hc表达明显强于低度恶性胶质瘤(P=0.002);4F2hc表达与胶质瘤Ki-67标记指数存在明显正相关(P=0.003), 但与微血管密度无明显相关性(P=0.214)。  结论  4F2hc与胶质瘤的发生和发展关系密切, 可能在胶质瘤的恶性增殖过程中具有重要作用。   相似文献   
59.
The present paper describes the detection of an autoantibody for glutamic pyruvic transaminase (GPT) in sera of patients with chronic hepatic disorders. In 16 out of 500 patients, the existence of an antibody for pig GPT was demonstrated by the double antibody method, gel filtration and radioimmunoelectrophoresis. The antibody was demonstrated as an immunoglobulin G (IgG) with either polyclonal or monoclonal type (kappa or lambda). The binding portion of IgG with GPT was determined as the fragment Fab, but not Fc of IgG. Because the binding of 125I-pig GPT with the patient's antibody was displaced by human GPT, this antibody may have the characteristic of cross reacting with both pig and human GPT. Although the mechanism of production of the antibody for GPT and the pathological significance of the antibody in chronic hepatic disorders remained obscure, possible inhibition of GPT activity in serum is suggested in the presence of this antibody.  相似文献   
60.
Zero-mass metamaterials comprise an orifice and a thin film. The resonance between the film and the air mass of the orifice hole is caused by sound waves, which significantly decreases the transmission loss at a specific frequency. The study novelly incorporates acoustic metamaterials in the delay tube of an interference silencer. In this case, it is determined that an interference silencer and a “side-branch silencer with two different branch pipe lengths” can be realized in a single silencer. At certain frequencies, the acoustic mass of the acoustic metamaterial approaches zero, which results in an interference silencer with the full length of the delay tube applied. At other frequencies, the acoustic metamaterial acts as a rigid wall with high transmission loss, thereby reflecting sound waves at the zero-mass metamaterial location. In this case, it is a side-branch silencer with two different tube lengths, corresponding to the tube lengths from the entrance and exit of the delay tube to the zero-mass metamaterial, respectively. The incorporation of zero-mass metamaterial into an interference-type silencer can introduce the silencing effect of a side-branch silencer with two different branch tube lengths without increasing the volume of the interference-type silencer. Theoretical values were obtained using the transfer matrix. Consequently, the theoretical and experimental values were close, enabling us to predict the transmission loss of the proposed silencer.  相似文献   
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