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71.
目的:探讨对巨大下颌骨囊性病变进行分期治疗的效果。方法:选择2005—2009年在本院收治的下颌骨范围大于5cm的囊性病变18例,其中伴牙列不齐者6例,一期局麻下行减压术,待范围减小至小于原来的1/2后,行二期全麻下囊性病变摘除术,即刻Bio-oss骨粉植入,术后每月定期拍摄口腔全景片观察骨密度变化,伴牙列不齐的6例患者手术后2个月开始以常规正畸加力牵引。结果:一期术后4~6个月,病变减小至原来的1/2左右,二期术后6~12个月,骨粉与周围正常骨密度基本一致,2~3a后无一例复发。6例牙列不齐的患者,经1~2a正畸治疗后,错畸形得以矫正。结论:分期治疗既彻底摘除了病变,又保存了下颌骨的连续性及自体牙,还可同时结合正畸治疗,改善错畸形,提高美学效果。  相似文献   
72.
Objetives: Assess levels of trait anxiety, state anxiety and dental anxiety before extraction of lower third molars and check the correlation and reliability of the scales used for the measurement of preoperative anxiety. Study Design: A prospective study of patients treated with extraction of a lower third molar between September 2010 to December 2010 was carried out. A total of 125 patients were included in the study. All of them were patients of the Oral Surgery and Implantology Department (Valencia University Medical and Dental School, Valencia, Spain). Before surgery, patients had to complete a preoperative protocol with 4 scales: the STAI-T (State-Trait Anxiety Inventory-Trait) for measuring trait anxiety, the STAI-S (State-Trait Anxiety Inventory-State) for measuring state anxiety, and DAS (Dental anxiety Scale of N. Corah) and APAIS (Amsterdam Preoperative anxiety and Information Scale) for measuring dental anxiety. Results: Patients undergoing extractions of an impacted lower third molar showed low levels of trait anxiety and moderate levels of state anxiety and dental anxiety. Higher levels of trait anxiety were obtained for older patients. Women had higher mean levels of dental anxiety and state anxiety that men with a statistically significant difference in STAI-S scales, DAS, and APAIS. Patients with higher trait anxiety and state anxiety showed higher levels of dental anxiety. A significant correlation (p ≤ 0.01) (p = 0.00) was found between the four scales used to measure anxiety. The scale showed higher correlation was STAI-S scale. The 4 scales showed high reliability (α of C.> 0.80). Conclusions: Patients with highest levels of trait anxiety and state anxiety, had more dental anxiety. The STAI-T, STAI-S, DAS and APAIS scales provided useful information about anxiety before the extraction of lower impacted third molars. The STAI-S is the scale with highest correlation and reliability. Key words:Extraction of impacted lower third molars, preoperative anxiety, dental anxiety, trait anxiety, state anxiety.  相似文献   
73.
Ecotoxicology - Each year, the European Food Safety Authority, supported by a network of experts in the EU Member States, assesses and publishes the environmental risks of 30–40 pesticides...  相似文献   
74.
Bullous pemphigoid (BP) is an autoimmune, acquired, cutaneous disease caused by the production of autoantibodies against hemidesmosomes'' components in the basement membrane. The estimated incidence in Europe ranges from 7 to 43 cases per million inhabitants per year. Several studies have reported an association between BP and neurological disorders (ND). Our cohort of Bullous pemphigoid and ND is the first in Brazil and showed a significantly high prevalence of neurological and/or psychiatric diseases, especially cerebrovascular accident (CVA) and dementia, in agreement with the prevalence reported in several studies published in the medical literature in recent years.  相似文献   
75.
Spain is a relevant producer of oats (Avena sativa), but to date there has been no study on the occurrence/co-occurrence of mycotoxins in oats marketed in Spain. The present study is addressed to overcome this lack of knowledge. One hundred oat kernel samples were acquired across different Spanish geographic regions during the years 2015–2019 and analyzed for mycotoxin content using an ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC–ESI–MS/MS) method and matrix-matched calibration. The focus was on the regulated mycotoxins although other relevant mycotoxins were considered. The percentage of incidence (levels ≥ limit of detection), mean and range (ng/g) of mycotoxins were as follows: zearalenone (66%, mean 39.1, range 28.1–153), HT-2 toxin (47%, mean 37.1, range 4.98–439), deoxynivalenol, (34%, mean 81.4, range 19.1–736), fumonisin B1 (29%, mean 157.5, range 63.2–217.4), and T-2 toxin, (24%, mean 49.9, range 12.3–321). Fumonisin B2, 3-acetyldeoxynivalenol, aflatoxins B1, B2, and G2, and ochratoxin A were also detected at low levels, but aflatoxin G1 was not. The maximum limits established by the European Commission for unprocessed oats were not exceeded, except for zearalenone (in one sample), and the sum of aflatoxins (in two samples). Mycotoxin co-occurrence at quantifiable levels in the same sample (two to five combinations) was found in 31% of samples. The most common mixtures were those of HT-2 + T-2 toxins alone or together with deoxynivalenol and/or zearalenone.  相似文献   
76.
In humans, CD56, CD161, CD16, CD94 or CD57 represent prototypic markers of NK cells, although they are also found on a subset of CD8+ T cells. We propose here that the expression of NK receptors on CD8+ T cells can be considered a marker of cytotoxic effector T cells that are expanded in vivo after antigenic activation leading to extensive proliferation. The persistence of antigen will lead to loss of co-stimulatory molecules, telomere shortening and defective IL-2 production, changes that define the state replicative senescence in T lymphocytes. The majority of these "effector/senescent" T lymphocytes are CD8+, CD45RA+, CD11a(bright), CD28-, CD27-, CD62L- and CCR7-. They are cytotoxic T cells with strong expression of intracytoplasmic perforin and granzyme, but with low proliferative capacity and defective IL-2 production. Many of these characteristics are shared by the recently defined "effector/memory" T cells, being mainly distinguished by the absence of CD45RA expression on the memory cells. The expression of NK receptor in these effector cells will probably contribute to the regulation of their cytotoxic function. Expansion of cells with these characteristics can be found not only in the elderly but also in other clinical conditions involving chronic activation of the immune system such as viral infections, rheumatic and autoimmune diseases or tumors. Another subset of T cells that expresses the NK receptors is the alpha-galactosyl-ceramide specific T cell subset defined by the expression of canonical Valpha24JalphaQ TCR, recognition of CD1d and secretion of high amounts of IL-4 and IFN-gamma. However, the changes observed in the expression of NK-R on T cells associated to immunosenescence can not be attributed to expansion of this particular T cell subset, although alterations in the number and function of these cells have been demonstrated in some autoimmune diseases.  相似文献   
77.
78.
Polycyclic aromatic hydrocarbons (PAHs) are assumed to be the primary determinant of oil petroleum toxicity. Since the PAH content in Prestige oil was relatively high, we investigated the effects of different oil fractions (crude or weathered oil -0.05 to 50 g/L, and shaken or sonicated water accommodated fractions, WAFs, 25-100%, v/v) on the embryo-larval development of medaka (Oryzias latipes). Concentrations of summation operator16PAHs analyzed in the incubation medium were highest in the shaken WAF followed by the crude oil, the sonicated WAF and the weathered oil. Both oils (> or =0.25 g/L) induced developmental abnormalities whereas no significant effects were seen in the WAF exposures. In vivo morphometric analysis of the surface of the gallbladder during advanced embryo organogenesis (192 h post-fertilization, hpf) revealed significant dilation in both WAF exposures (>3 x 10(4) microm(2) at > or =25%, v/v, compared to <1.7 x 10(4) microm(2) at 0%, v/v) followed by the crude oil (>2.2 x 10(4) microm(2) at > or =0.05 g/L). Fluorescent aromatic compounds were observed in the gallbladder and the yolk sac of 168-hpf embryos exposed to all oil fractions. Results suggest the presence of components in both oils capable of penetrating the chorion and inducing a toxicity not observed in the WAFs. Hence, the hazard and risk assessment of Prestige oil should not be based solely on the presence of PAHs since proximity or direct contact may induce toxicity not associated exclusively to these compounds. This research offers a new hypothesis for explaining the reported biological observations, which could be correlated to direct oil exposure rather than the traditional mechanism of waterborne PAH exposure. Further research is needed to identify those oil components responsible for toxicity.  相似文献   
79.
目的:探讨小鼠角膜移植排斥反应中植片浸润细胞类型及引流淋巴结细胞表型的变化。 方法:建立小鼠角膜移植模型,术后不同时间点进行临床观察及角膜免疫荧光组织化学染色。采用三色流式细胞术分析移植术后3d颌下淋巴结(SMLN)、颈浅淋巴结(SCLN)的细胞表型变化。 结果:角膜移植术后6h,中性粒细胞、树突状细胞、巨噬细胞开始聚集并逐渐浸润植片;24hCD4^+T和CD8^+T细胞出现并侵入植片,2wk时达到高峰;术后12~21d所有植片均被排斥。移植后3dSMLN内CD4^+T细胞比例较正常时明显下降(P=0.038),而SCLN各细胞比例无明显变化。 结论:角膜移植术后植片迅速出现髓系及淋巴细胞浸润,伴有引流的SM LN内早期CD4^+T细胞比例下降,二者间有一定关联。  相似文献   
80.
A 9‐year‐old patient with the classical clinical picture of Hutchinson‐Gilford progeria (HGP) is described. The karyotype shows a 46,XY,del(1)(q23) constitution. Our findings suggest that the interval 1q23 may play a roll in the etiology of HGP. A perturbation in glycosylation in connective tissue has been demonstrated in patients with this condition. This abnormality may be due to a defect in the UDP‐galactose:β‐N‐acetylglucosamina‐β‐1,4‐galactosyltransferase 3 (B4GALT3) gene that has been mapped in the interval 1q21‐23. The cytogenetical analyses of this patient suggest that the B4GALT3 gene could be involved in the pathogenesis of HGP. © 2002 Wiley‐Liss, Inc.  相似文献   
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