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941.
PURPOSE: To evaluate the clinical features of nosocomial epidemic keratoconjunctivitis(EKC) occurring in the ophthalmology ward of Sapporo Medical University Hospital and to devise preventive measures for it. MATERIALS AND METHODS: We studied the symptoms and clinical course of 2 patients who had EKC and 16 patients who had EKC caused by nosocomial infections in our hospital. We attempted to detect adenovirus antigen and viral DNA from conjunctival swabs and also to isolate the virus. RESULTS: The clinical symptoms of EKC were conjunctival hyperemia in 18 patients(100%), conjunctival follicles in 11 patients (61.1%), discharge in 8 patients(44.4%), superficial punctate keratopathy in 7 patients(38.9%), swelling of the eyelids in 3 patients(16.7%), and fever in 3 patients(16.7%). 72% were positive for Adeno-check. Adenovirus type 4 was isolated from the conjunctival swabs. We considered that the route of hospital infection was infection from the doctor's hands, from eye drops, and from contact lenses. We disclosed that nosocomical EKC had occurred in our hospital. The hospital infection was eliminated by closing the ophthalmology ward and sterilizing instruments and washing hands. CONCLUSIONS: The delay of proper measures increased the risk of nosocomical infection. We recognized the importance of careful observation of patients and immediate preventive efforts in nosocomical infection.  相似文献   
942.
PURPOSE: To examine the strabological findings after macular translocation surgery with a 360 degrees retinotomy. METHODS: Thirty-two patients who underwent macular translocation surgery were divided into three groups based on their responses to the Bagolini striated lenses test: fusion, ignoring the image, and diplopia. The relevant factors affecting binocularity were compared among the three groups. RESULTS: Five patients had peripheral fusion and three of these had gross stereopsis. Fifteen patients ignored the second image, and 12 patients had diplopia. The objective angle of macular rotation was smaller in the patients with peripheral fusion (15.0 +/- 6.1 degrees) than in those with diplopia (32.7 +/- 11.7 degrees). The subjective angle of cyclotorsion in those with peripheral fusion (6.0 +/- 4.2 degrees) was smaller than in those who ignored the image ("ignoring" group; 20.5 +/- 9.19 degrees) and the diplopia group (30.7 +/- 12.8 degrees). The amount of torsional sensory compensation in patients with diplopia (2.08 +/- 3.83 degrees) was significantly smaller than in those with peripheral fusion (9.00 +/- 7.42 degrees) and in the ignoring group (6.73 +/- 3.86 degrees). Patients with peripheral fusion were significantly younger (54.2 +/- 14.3 years) than those in the ignoring group (67.7 +/- 10.0 years) and those with diplopia (68.0 +/- 5.4 years). CONCLUSIONS: Adaptive mechanisms are activated to reduce the surgically induced objective angle of cyclotorsion, and a cyclodeviation of 15 degrees was the critical angle separating those who had peripheral fusion from those who did not. This value corresponds to the cyclofusional amplitude in normal adults.  相似文献   
943.
PURPOSE: To evaluate the efficacy of a biodegradable polymeric scleral plug containing the immunosuppressive agent, FK506, in a rabbit model for experimental uveitis. METHODS: The scleral plugs were prepared by dissolving poly(DL-lactide-co-glycolide; PLGA) and FK506 (weight, 8.5 mg; length, 5 mm; 1% FK506). The release of FK506 was evaluated in vitro by spectrophotometry on days 1, 3, 7, 14, 21, and 35. In vivo, FK506 concentrations of the vitreous were measured by high performance liquid chromatography 2 and 4 weeks after intravitreous plug implantation in pigmented rabbits. Sixteen pigmented rabbits were immunized twice subcutaneously with 10 mg of Mycobacterium tuberculosis H37Ra antigen. Twelve days later, the right eyes of all rabbits were challenged with an intravitreal injection of 50 micro g of antigen. After the first challenge, the 16 eyes of 16 pigmented rabbits were divided into two groups. Scleral plugs were implanted into the vitreous of the right eye of eight rabbits. Eight control rabbits received a sham device. The aqueous protein concentrations and cell counts were determined on postchallenge days 7, 14, and 28. To simulated chronic inflammation, the eyes were rechallenged with intravitreal antigen on day 14 and were observed for 1 month. Inflammation of the anterior chamber and the vitreous were graded clinically by two masked observers. Retinal function was evaluated by electroretinography (ERG) and histologic examination. RESULTS: Clinical scores (anterior chamber cells, flare, and vitreous opacity) showed that treated eyes had significantly less inflammation than untreated eyes (P<0.001). Quantitative analysis of inflammatory cells (P<0.001) and protein concentrations (P<0.0001) in the anterior chamber showed significant decreases in treated eyes. Histopathologic examination showed marked inflammation and tissue disorganization in the untreated eyes. No retinal toxicity was detected, histopathologically and electroretinographically. After antigen rechallenge, inflammation in experimental eyes was still less than in control eyes. CONCLUSIONS: Intravitreal sustained-release of FK506 from a biodegradable polymeric scleral plug was highly effective in suppressing the inflammation of experimental uveitis in a rabbit model for at least 6 weeks. This device may be useful in the management of patients with severe chronic uveitis.  相似文献   
944.
The purpose of this study was to evaluate the corneal irregular astigmatism following photorefractive keratectomy (PRK) for myopia. The corneal topography of 30 eyes of 26 patients was measured with the TMS-1 videokeratoscope before and 1 month after PRK. Axial dioptric data were decomposed into four components; A0 (Sphericity), C1 x 2 (Asymmetry), C2 x 2 (Regular astigmatism), and C3 (higher-order irregularity) for the central 3 and 6 mm zone by Fourier series harmonic analysis. Post-operative topographies were divided into those with an irregular and those with a homogeneous pattern, and the Fourier components were compared. In the 6 mm zone, A0 was significantly decreased (P < 0.001), and C1 x 2, C2 x 2, and C3 were significantly increased (P = 0.001, 0.005, 0.002, respectively). In the 3 mm zone, A0 decreased (P < 0.001) and C1 x 2 increased (P < 0.001) significantly. C1 x 2 was correlated with the post-operative corrected visual acuity (P < 0.001, r = 0.647). The irregular pattern group had a larger C1 x 2 component (P < 0.001). The treatment displacement was not correlated with any component. In conclusion, irregular topography due to intraoperative drift or asymmetrical wound healing may play a more important role in the post-operative corneal optical property than mild treatment displacement.  相似文献   
945.
Phototransduction in vertebrate photoreceptor cells mediated by rhodopsin is one of the most comprehensively examined G protein-coupled receptor (GPCR) signaling pathways. The signal transduction pathway can be mapped from the initial absorption of light to conformational changes within rhodopsin, through activation of the G protein transducin, and to the ultimate closure of the cation cGMP-gated channels in the plasma membrane. Furthermore, phototransduction has become an intensely studied model system for understanding the desensitizing processes that allow reduced non-linear responses of photoreceptor cells to increasing levels of illumination. Although some general themes appear to occur in GPCR systems, the details of these desensitizing processes are likely to be specific to each of the receptors. These differences are attributed to the fact that each receptor has unique kinetic constraints, amplification levels, tolerance to basal constitutive activity, intracellular internalization and recycling, redundancy of isoforms, and morphologies of the cell of their expression. One of the biochemical processes that are believed to be a common part of this desensitization of the GPCR-mediated cascade is receptor phosphorylation catalyzed by members of a small family of the GPCR kinases. The enzymatic, physiological and genetic aspects of rhodopsin phosphorylation and rhodopsin kinase have been characterized extensively over the last 30 yr. However, new structurally based approaches to examining rhodopsin kinase and rhodopsin phosphorylation are still awaiting further investigations. We present here a summary of the current understanding of rhodopsin phosphorylation and the properties of rhodopsin kinase, along with some expectations of future investigations into these topics.  相似文献   
946.
Isoproterenol is widely used as a provocative medium for vasovagal responses during tilt testing. Dose of isoproterenol infusion is generally titrated empirically by increase in resting heart rate before tilt up. To determine the optimal increase in resting heart rate with isoproterenol for tilt-induced vasovagal responses, we studied 97 consecutive patients with unexplained syncope. After the end of a negative baseline tilt (80 degrees for 30 min), the isoproterenol tilt was performed using one of two protocols: two-stage isoproterenol-tilt protocol, with doses of 0.01 and 0.02 microg/kg per min for 10 min each, or one-stage isoproterenol-tilt protocol, with a dose of 1 or 2 microg/min for 10 min. The resting heart rate increase was defined as a percentage increase in the resting heart rate after isoproterenol infusion, compared to the baseline heart rate before the tilt test. In 117 tilt procedures, 28 (93%) of the 30 positive responses occurred with a resting heart rate increase of > or = 21%. With the resting heart rate increase of 60 and 100%, 18 (60%) and 27 (90%) positive responses were observed, respectively. In conclusion, the minimum resting heart rate increase of > or = 21% was required to provoke a vasovagal response during subsequent isoproterenol-tilt (80 degrees for 10 min). Preferably, heart rate should be increased to 60-100% by isoproterenol titration before tilting.  相似文献   
947.
Medaka (Oryzias latipes) were continuously exposed to various concentrations of two alkylphenols, 4-nonylphenol (NP) and 4-tert-octylphenol (OP), from fertilized eggs to 60 d posthatch. The effects on sexual differentiation and hepatic vitellogenin (VTG) induction in medaka were assessed to elucidate the lowest-observed-effect concentrations (LOECs) of NP and OP for these events during early life stages. The LOECs of NP and OP for these events were 11.6 and 11.4 microg/L, respectively. These results suggest that NP and OP may have adverse effects at similar concentrations during early life stage in medaka. Additionally, we investigated whether the abnormal sex differentiation induced by these alkylphenols would be permanent or reversible once the medaka were returned to clean water. The appearance of the secondary sex characteristics reverted from female to male when fish were returned to clean water. However, gonadal histology showed that intersex gonads still existed, even after the fish were transferred to clean water for two months. These results suggest that the induced feminization of secondary sex characteristics in medaka exposed to alkylphenols during the stage of sexual differentiation may not always be permanent, but the gonadal alteration (testis-ova) may continue much longer.  相似文献   
948.
PURPOSE: To investigate quality of life (QOL) and associated factors in centenarians, we conducted a visitation interview survey for all male and one half of the female centenarians living in Japan, and studied QOL, lifestyle and health status. METHODS: All the male centenarians and a randomly-sampled half of the female centenarians living in Japan were included in the study based on the National Census. Finally, 556 male and 1341 female centenarians participated in the present visitation interview survey and were studied using a structured questionnaire. QOL was assessed from 3 aspects; activities of daily life (ADL), cognitive function (CF) and mental health (MH). RESULTS: Individuals having superior ADL accounted for 30.9% of the male and 13.6% of the female centenarians, those with superior CF were 58.1% and 35.6%, respectively, and those with superior MH were 39.2% and 26.8%, providing evidence that superior QOL was more dominant in males than in females. There were no effects of residential areas (north, east, middle, west, southwest and south of Japan) on the prevalence of ADL, CF and MH. Multiple logistic regression analyses conducted independently, for ADL, CF and MH as dependent valuables revealed that habitual exercise, less decline in visual ability and preservation of masticating ability were associated with better results for these 3 aspects of male centenarians' QOL, and that habitual exercise, less decline in visual ability, spontaneous awakening in the morning, good appetite and having cohabitating family members were associated with superior QOL in the females, suggesting that more factors are operating in the latter. CONCLUSIONS: Several lifestyle factors were found to be associated with preservation of QOL in centenarians in Japan. These results should facilitate establishing a public health and welfare policy for the most senior citizens, a group that has been increasing in Japan.  相似文献   
949.
Nocturnal eating/drinking disorder (NE/DS) is a rare syndrome that includes disorders of both eating and sleeping. It is characterized by awakening in the middle of the night, getting out of bed, and consuming large quantities of food quickly and uncontrollably, then returning to sleep. This may occur several times during the night. Some patients are fully conscious during their nocturnal eating, while some report total amnesia. The aetiology of NE/DS is still unclear, and there is no satisfactory treatment. Four patients with NE/DS are described. Treatment with a selective seroronin reuptake inhibitor (SSRI) was effective in controlling their episodes of nocturnal eating. To our knowledge, this is the first published case report of successful treatment with SSRIs in NE/DS.  相似文献   
950.
To identify genetic elements that might confer susceptibility to diabetic nephropathy, we performed a genome-wide analysis of gene-based single nucleotide polymorphisms (SNPs) in a large cohort of Japanese patients with diabetes. In case-control association studies, patients with type 2 diabetes were divided into two groups, one having retinopathy as well as overt nephropathy and the other (the control group) having diabetic retinopathy but with no signs of renal involvement. Genotyping of these patients at >55,000 SNP loci indicated a gene encoding solute carrier family 12 member 3 (SLC12A3) to be a good candidate for the susceptibility to diabetic nephropathy, in view of a significant association of one landmark SNP located in the 24th intron (chi(2) = 15.4, P = 0.000087, odds ratio = 2.53 [95% CI 1.57-4.09]). Subsequent analysis of additional genetic variations in this gene identified several SNPs that were significantly associated with nephropathy, especially one in exon 23 (+78 G to A: Arg913Gln, chi(2) = 18.5, P = 0.00002, odds ratio = 2.53 [95% CI 1.64-3.90]). The results implicated that substitution of Arg913 to Gln in the SLC12A3 gene might reduce the risk to develop diabetic nephropathy and suggested that the gene product might be a potential target for the prevention or treatment of this disease.  相似文献   
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