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31.
Lamellar ichthyosis (LI) is characterized by generalized scaling of the skin and is often resistant to ordinary emollients. Recently, Locobase(R) fatty cream containing a mixture of 5% lactic acid and 20% propylene glycol (LPL) was found to be markedly effective in a pilot study. To consolidate this finding, a double-blind study comparing LPL with the corresponding mixture in Essex(R) (Diprobase(R)) cream (LPE) and Locobase(R) fatty cream containing either 5% urea or 20% propylene glycol was conducted in 20 patients with LI. Before and after applying the creams twice daily on each of the four extremities for 4 weeks, the following investigations were performed: scoring of xerosis, scaling and erythema, measurements of skin hydration (capacitance) and transepidermal water loss (TEWL), and moulding of the skin surface (replicas). Xerosis was reduced by all four creams, but significantly more so by LPL (P < 0.001) and LPE (P < 0.01). Scaling was only reduced by LPL (P < 0.001) and LPE (P < 0.01), which also caused a slight increase in the erythema score (P < 0.05 for both). The patients' weekly evaluation of symptoms showed that LPL produced the most rapid effect: the response rate after 4 weeks was 63%. Skin hydration and TEWL were both significantly increased by LPL and LPE, whereas skin roughness was reduced most by LPL. Fourteen patients preferred LPL over the other cream formulations. Ten patients continued using LPL for up to 8 weeks with good results and no side-effects other than occasional irritation in the skin folds. LPL is a major advance in the topical treatment of LI that suits most patients. Some patients, however, seem to prefer the more hydrophilic LPE formulation. Both formulations effectively reduce hyperkeratosis and xerosis, but may cause slight irritation and adversely affect the epidermal barrier function.  相似文献   
32.
本文报道了对犬实验性急性出血性胰腺炎(P组)与加用氯喹(PI组)时Ⅱ型肺泡上皮细胞的板层小体体视学形态定量的研究。结果发现:P组板层小体的体积密度(Vv),表面积密度(Sv)及数密度(Nv)分别较对照组下降29.06%,30.28%,及40.75%;其Sv及Nv分别较PI组减少23.8%和30.26%。结果提示:并发于急性出血性胰腺炎的肺损伤以肺泡表面活性物质系统受损为一重要的表现形式。板层小体数目显著减少,一定程度影响到肺泡的表面张力,从而造成肺不张。肺损伤与磷脂酶A_2的作用有关;氯喹在维持板层小体的数量方面可能有一定的作用。  相似文献   
33.
In an earlier report, a modification of the Attwood's stain was used to study sections of decalcified bone and the procedure aided in the distinction between lamellar and woven bone. Lamellar bone showed preferential affinity for phloxine (red) yet resisted differentiation with tartrazine (yellow), while woven bone stained well with tartrazine. In addition, osteoid seams were identified by their affinity for tartrazine. Differential staining was abolished by pretreatment with periodic acid. Recently, accidental use of potassium permanganate in an acidified medium of pH 1.94, instead of pH 6.44, yielded unexpected results with a much sharper, consistent distinction between woven and lamellar bone. This probably reflects changes in the noncollagenous, interfibrillary matrix proteins of bone, but the exact reason(s) is not known. In our view, this serendipitous modification represents an advance over the previous method, and has allowed us to study the structure of bone in some of the systemic disorders, e.g., osteogenesis imperfecta, with greater ease than before. This method does, however, suffer the disadvantage of interfering with the intensity of the staining of any cartilaginous matrix, and the original application is still of value. Received October 26, 1999; accepted February 28, 2000.  相似文献   
34.
陈玲 《医疗设备信息》2005,20(11):70-70,32
在做LASIK手术时很多术者认为有一把好的角膜刀是非常重要的,其实还要有一支好的工程师队伍,这才是确保LASIK屈光手术成功的最基本条件。  相似文献   
35.
Terje Lømo 《Hippocampus》2009,19(7):633-648
The functional organization of the perforant path input to the dentate gyrus of the exposed hippocampus was studied in adult rabbits anesthetized with urethane and chloralose. Electrical stimulation of perforant path fibers caused excitation of granule cells along narrow, nearly transverse strips (lamellae) of tissue. Stimulation of granule cell axons (mossy fibers) in CA3 caused antidromic activation of granule cells along similar strips. Paired‐pulse stimulation revealed marked changes in granule cell excitability both within a lamella (on‐line) and for several mm off‐line along the septo‐temporal axis of the dentate gyrus. After the first pulse, granule cells were inhibited for up to about 100 ms and then facilitated for up to hundreds of ms. Feedback activity along mossy fiber collaterals exciting local inhibitory and excitatory neurons appeared to dominate in producing on‐ and off‐line inhibition and facilitation. Neurons mediating these effects could be inhibitory basket cells and other inhibitory interneurons targeting granule cells on‐ and off‐line. In addition, excitatory mossy cells with far reaching, longitudinally running axons could affect off‐line granule cells by exciting them directly or inhibit them indirectly by exciting local inhibitory interneurons. A scheme for dentate gyrus function is proposed whereby information to the dentate gyrus becomes split into interacting transverse strips of neuronal assemblies along which temporal processing occurs. A matrix of neuronal assemblies thus arises within which fragments of events and experiences is stored through the plasticity of synapses within and between the assemblies. Similar fragments may then be recognized at later times allowing memories of the whole to be created by pattern completion at subsequent computational stages in the hippocampus. © 2008 Wiley‐Liss, Inc.  相似文献   
36.
角膜内皮移植已成为治疗角膜内皮病变的首选方法.作为目前主流的2种角膜内皮移植手术——后弹力层剥除自动板层刀制备的角膜内皮移植术和后弹力层角膜内皮移植术,前者手术操作易于掌握,但角膜植片仍带有部分基质;后者术后视觉质量好,但手术操作较难掌握,二次手术率较前者高.大气泡和自动板层刀辅助的后弹力层前膜角膜内皮移植术在自动板层刀制备角膜内皮植片的基础上,用大气泡法暴露中央6.5 mm直径的后弹力层前膜,本术式既有后弹力层角膜内皮移植术后的视觉效果,手术操作又易于掌握,值得推广.  相似文献   
37.
准分子激光原位角膜磨镶术后界面性角膜炎的临床观察   总被引:2,自引:4,他引:2  
目的 :动态观察准分子激光原位角膜磨镶术 (LASIK)后界面性角膜炎 (DLK)的临床变化 ,同时对其角膜瓣下临床特点及处理方法进行分析。 方法 :对 35 0 0例行LASIK后 1 0例 (1 8只眼 )发生DLK患者进行观察。按3、7、1 4天和 1、2、6个月不同时间进行视力、裂隙灯显微镜检查。 结果 :局部用激素、抗生素治疗 1周 ,症状控制 ,1~ 2个月全部吸收。视力恢复至 1 .0~ 1 .5 (1 6只眼 ) ,0 .8~ 1 .0 (2只眼 )。 结论 :LASIK后DLK常发生在术后 1~ 7天内 ,迟发者偶见 ,男性多于女性 ,以局部激素治疗为主 ,严重患者需全身激素加抗生素治疗。DLK早期须与角膜上皮植入、层间感染鉴别  相似文献   
38.
对解肌舒筋口服液中所合成分葛根素、麻黄碱进行鉴别,认为该方中挥发油制成芳香水与其他提取物混合溶解,不易产生分层,稳定性较佳,有效成分均匀分散,药品质量稳定。  相似文献   
39.
This report presents a Libyan child with congenital ichthyosis of the recessive lamellar variety complicated by severe ectropion of both upper and lower eyelids. Over a period of 12 months the degree of ectropion diminished and the anterior segments of the eyes were preserved using regular lubricating drops, vitamin A ointment and intermittent topical antibiotic therapy. Despite the pronounced initial upper eyelid ectropion no surgery was required to relieve the ectropion or prevent corneal exposure.  相似文献   
40.
Ultraviolet light (UVR) induces a myriad of cutaneous changes, including delayed disruption of the permeability barrier with higher doses. To investigate the basis for the UVB-induced barrier alteration, we assessed the epidermal lamellar body secretory system at various time points before and after barrier disruption with a single high dose of UVB (7.5 MED) to murine epidermis. Morphological data were correlated with changes in epidermal proliferation and lipid synthesis, indicative of lamellar body generation. Twenty-four hours following UVB, the stratum corneum (SC) is normal, but a layer of abnormal, vacuolated, and lamellar body (LB)-deficient cells is present, immediately beneath the stratum granulosum (SG)/SC interface. Immediately subjacent to this band of damaged cells, normal keratinocytes that contain intact LBs are present. By 72 h, concomitant with the appearance of a barrier abnormality, extensively damaged cells persist at the SC/SG interface, and abnormal lamellar membrane structures appear in the lower SC. Upper stratum spinosum (SS) and lower SG cells appear normal, with increased numbers of LBs. A barrier abnormality is still present at 96 h, in association with membrane abnormalities in the lower SC interstices, but up to four normal-appearing, subjacent SG cell layers are present. By 120 h, accelerated LB formation and precocious LB extrusion occur throughout the thickened SG; normal lamellar membranes are present in the lower SC; and barrier recovery is almost complete. Whereas, epidermal synthesis of the major barrier lipid species (i.e., cholesterol, fatty acids, and ceramides, including acylceramides) is reduced or unchanged at 24 and 48 h, it increases significantly 72 h after exposure to UVB. Therefore, the delayed disruption of the permeability barrier following acute UVB exposure results from the arrival of a band of lamellar body-incompetent (i.e., damaged) cells at the SG/SC interface. The subsequent, rapid recovery of the barrier, in turn, results from compensatory hyperplasia of subjacent, undamaged SS/SG cells, generating increased numbers and contents of LB. These results underscore the critical role of the stratum compactum in mediating barrier function, and suggest that beneficial therapeutic effects of UV exposure may be due to enhanced lipid production and barrier regeneration.  相似文献   
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