首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   217篇
  免费   8篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   7篇
妇产科学   11篇
基础医学   34篇
口腔科学   8篇
临床医学   16篇
内科学   40篇
皮肤病学   1篇
神经病学   18篇
特种医学   3篇
外科学   22篇
综合类   1篇
预防医学   22篇
眼科学   4篇
药学   27篇
肿瘤学   12篇
  2022年   6篇
  2021年   9篇
  2020年   6篇
  2019年   5篇
  2018年   3篇
  2017年   7篇
  2016年   6篇
  2015年   13篇
  2014年   7篇
  2013年   14篇
  2012年   10篇
  2011年   11篇
  2010年   5篇
  2009年   13篇
  2008年   20篇
  2007年   15篇
  2006年   15篇
  2005年   9篇
  2004年   19篇
  2003年   14篇
  2002年   13篇
  1998年   1篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1985年   1篇
  1984年   1篇
排序方式: 共有227条查询结果,搜索用时 46 毫秒
51.
Objective:To explore the mediation and moderation effects of personality traits on the relationship between self-perceived malocclusion and the psychosocial impact of dental esthetics.Materials and Methods:The sample included 252 subjects (62% female) aged 12–39 years. Self-perceived malocclusion was estimated using the 10-point scale Aesthetic Component of the Index of Orthodontic Treatment Need. The Psychosocial Impact of Dental Aesthetics Questionnaire was used to assess the psychological impact and the Big Five Inventory for personality traits. Moderation and mediation effects were evaluated with Pearson correlations and stepwise regression analysis, respectively.Results:Self-perceived malocclusion ranged from 1 to 8 and was the most significant predictor of psychosocial impact of dental esthetics, whose unique contribution accounted for 11%–36.4% of variability, while age and sex accounted for 1.2%–2.5%. Personality traits had no mediating effect on this relationship. The moderating effect of agreeableness was present in the relationship between self-perceived degree of malocclusion and Social Impact (SI), Psychological Impact (PI), and Aesthetic Concern (AC) (ΔR2  =  0.035, 0.020, and 0.013, respectively; P < .001), while conscientiousness affected the relationship between perception of malocclusion and SI and PI (ΔR2  =  0.018 and 0.016, respectively; P < .05). In people with lower agreeableness and conscientiousness, increasing the severity of self-perceived malocclusion leads to less increase in SI and PI. In people with lower agreeableness, the increase influences AC in a similar manner. Extraversion, neuroticism, and openness do not have a moderating effect.Conclusions:The relationship between self-perceived malocclusion and the psychosocial impact of dental esthetics appears to be moderated and not mediated by personality traits. Adolescents and young adults with lower agreeableness and conscientiousness seem to be less affected by the increased severity of self-perceived malocclusion, as demonstrated in reporting some psychosocial impacts.  相似文献   
52.
53.
A 77-year-old woman presented to the outpatient hematology clinic in August 2001 with leukocytosis, recurrent bacterial infections, sweating and weight loss. Bone marrow biopsy showed 80% infiltration with lymphoid cells having a prolymphocytic morphology. Flow-cytometric immunophenotype analysis showed that over 80% of the cells were positive for CD2, CD3, CD4, CD5 and CD7 antigens and negative for terminal deoxynucleotidyl transferase and CD1a antigens. T cell prolymphocytic leukemia (T-PLL) was diagnosed on the basis of these findings. The diagnosis was later confirmed by cytogenetic analysis and fluorescence in situ hibridization. The patient had the following karyotype: 46,X,der(X)t(X;3) (q28;p25) t(X;16)(p14;q12), der(3) t(X;3)(q28;p25), der(6) t (X;6) (p14;q25), (8) (q10), del(11) (q14q23), der(13) t (5;13) (q34;p11), der(13) t(13;14)(q22;q11), inv(14)(q11q32), der (16) t(X;16)(q28;q12), r(17)(p13q21), der(20) t(17;20) (q21; q13),22p+. The cytogenetic rearrangements der(6)t(X;6) (p14;q25), der(13)t(13;14)(q22;q11),t(5;13)(q34;p11), r(17) (p13q21) and t(17;20)(q21;q13) have not been described previously in the literature in patients with T-PLL.  相似文献   
54.
Purpose Gastric pentadecapeptide BPC 157 (BPC 157), which has been shown to be safe in clinical trials for inflammatory bowel disease (PL-10, PLD-116, PL14736, Pliva, Croatia), may be able to cure intestinal anastomosis dehiscence. This antiulcer peptide shows no toxicity, is limit test negative, and a lethal dose is not achieved. It is stable in human gastric juice. In comparison with other standard treatments it is more effective for ulcers and various wounds, and can be used without a carrier needed for other peptides, both locally and systemically (i.e., perorally, parenterally). We studied the effectiveness of BPC 157 for ileoileal anastomosis healing in rats. Methods We assessed ileoileal anastomosis dehiscence macroscopically, histologically, and biomechanically (volume [ml] infused through a syringe-perfusion pump system (1 ml/10 s), and pressure [mmHg] to leak induction [catheter connected to a chamber and a monitor, at 10 cm proximal to anastomosis]), at 1, 2, 3, 4, 5, 6, 7, and 14 days. BPC 157 (10 μg, 10 ng, 10 pg/kg i.p. (or saline [5 ml/kg]) was first administered after surgery, while it was last given 24 h before either assessment or sacrifice. Results Throughout the experiment, both higher doses of BPC 157 were shown to improve all parameters of anastomotic wound healing. The formation of adhesions remained slight, the blood vessels were filled with blood, and a mild intestinal passage obstruction was only temporarily observed. Anastomosis without leakage induces markedly higher volume and pressure values, with a continuous increase toward healthy values. From day 1, edema was markedly attenuated and the number of granulocytes decreased, while from days 4 or 5 necrosis decreased and granulation tissue, reticulin, and collagen formation substantially increased, thus resulting in increased epithelization. Conclusion This study showed BPC 157 to have a beneficial effect on ileoileal anastomosis healing in the rat.  相似文献   
55.
BACKGROUND: The ever-increasing resistance to antibiotics is a serious worldwide problem. Antibiotic strategies for appropriate use of antimicrobials in hospitals are not well defined. METHODS: A questionnaire on "ABS maturity of hospitals" was the basis of an analysis as a part of an EU project. This questionnaire was sent to 12 hospitals in Slovenia including 11 general hospitals and one university hospital. MAIN FINDINGS: All 12 hospitals returned the questionnaires. Maturity of antibiotic strategies were considered moderate (3.74). Antibiotic consumption had the highest maturity ratio (4.44), followed by diagnostics (3.96), antibiotic-related relationships (3.58), antibiotic-related personnel development (3.44) and antibiotic-related organization (3.36). The availability of data on antibiotic consumption had the highest ranking; designation of and time resources for antibiotic officers were ranked lowest. CONCLUSION: In Slovenia the maturity of antibiotic strategies in general hospitals and in one university hospital is moderate. The data provide a basis for further development of antibiotic-related issues in hospitals.  相似文献   
56.
In spite of several reports demonstrating that acetylcholinesterase (AChE [EC 3.1.1.7]) expression is importantly regulated at the level of its mRNA, we still know little about the relationship between AChE mRNA level and the level of mature, catalytically active enzyme in the cell. Better insight into this relationship is, however, essential for our understanding of the molecular pathways underlying AChE synthesis in living cells. We have approached this problem previously (Grubic et al., 1995; Brank et al., 1998; Mis et al., 2003; Jevsek et al., 2004); however, recently introduced small interfering RNA (siRNA) methodology, which allows blockade of gene expression at the mRNA level, opens new possibilities in approaching the AChE mRNA-AChE activity relationship. With this technique one can eliminate AChE mRNA in the cell, specifically and at selected times, and follow the effects of such treatment at the mature enzyme level. In this study we followed AChE activity in siRNA-treated cultured human myoblasts. Our aim was to find out how the temporal profile of the AChE mRNA decrease is reflected at the level of AChE activity under normal conditions and after inhibition of preexisting AChE by diisopropyl phosphorofluoridate (DFP).AChE activity was determined at selected time intervals after siRNA treatment in both myoblast homogenates and in culture medium to follow the effects of siRNA treatment at the level of intracellular AChE synthesis and at the level of AChE secreted from the cell.  相似文献   
57.
Electrically-assisted gene delivery is a non-viral gene delivery technique, using application of square wave electric pulses to facilitate uptake of plasmid DNA into the cells. Feasibility and effectiveness of this method in vivo was already demonstrated, elaborating on pulse parameters and plasmid construction. However, there were no studies performed on sequencing and timing of plasmid DNA injection into the tumors and application of electric pulses. For this purpose we measured luciferase expression in two tumor models (LPB fibrosarcoma, B16F1 melanoma) after electrically-assisted gene delivery at varying time intervals between the pCMV-Luc plasmid injection and electroporation. Expression of luciferase was determined by measurement of its activity using luminometer. The results demonstrated that pCMV-Luc plasmid has to be injected before the application of electric pulses, since no measurable expression was detected in the tumors when pCMV-Luc plasmid was injected after electroporation of tumors. In both tumor models the highest transfection efficiency was obtained when pCMV-Luc plasmid was injected not less than 5 minutes but also not more than 30 minutes before the application of electric pulses. The results also demonstrated variability in the transfection efficiency depending on the tumor model. High expression was obtained in B16F1 tumor model (approximately 5500 pg luc/mg tumor) and lower in LPB fibrosarcoma (approximately 200 pg luc/mg tumor). In conclusion, our results demonstrate that regardless of the susceptibility of the tumors to electrically-assisted gene delivery, the best timing for pCMV-Luc plasmid is between 30 to 5 minutes prior to the application of electric pulses to the tumors.  相似文献   
58.
BACKGROUND: Early enteral nutrition (EN) after injury reduces septic complications, but upper digestive intolerance (UDI) occurring immediately post-trauma is a risk factor for pneumonia. Our study aimed to determine whether early intragastric feeding may lead to gastric intolerance and subsequent pneumonia in ventilated multiply injured patients. METHODS: This prospective study involved two groups of patients randomized either to immediate intragastric EN, or to delayed intragastric EN started later than 24 h after admission. UDI was diagnosed when gastric residual volume, measured with a 50-ml syringe after stopping the feeding for 2 h, exceeded 200 ml at least at two consecutive measurements, and/or when vomiting occurred. RESULTS: Out of 52 patients, 27 were included in the early EN group, and 25 in the delayed-EN group. On day 4, the early EN group received a greater amount of feeding because of intolerance problems occurring in the delayed-EN group (1175 +/- 485 ml vs. 803 +/- 545 ml). Twenty-five subjects--33% of the early EN patients and 64% of the delayed-EN patients--met the criteria for pneumonia (P = 0.050). On average, patients with pneumonia were older, more severely injured, and therefore required more ventilator days and a longer stay in the intensive care unit than patients without pneumonia. CONCLUSIONS: If properly administered, early enteral nutrition can decrease the incidence of upper intestinal intolerance and nosocomial pneumonia in patients with multiple injuries.  相似文献   
59.
The stable gastric pentadecapeptide BPC 157 (GEPPPGKPADDAGLV, M.W.1419), which was promising in inflammatory bowel disease (PL-10, PLD-116, PL-14736, Pliva) trials, protects against both acute and chronic alcohol-induced lesions in stomach and liver, but also, given peripherally, affects various centrally mediated disturbances. Now, in male NMRI mice BPC 157 (10 pg intraperitoneally, 10 ng and 10 microg, intraperitoneally or intragastrically) (i) strongly opposed acute alcohol (4 g/kg intraperitoneally) intoxication (i.e., quickly produced and sustained anesthesia, hypothermia, increased ethanol blood values, 25% fatality, 90-min assessment period) given before or after ethanol, and (ii) when given after abrupt cessation of ethanol (at 0 or 3 or 7 h withdrawal time), attenuated withdrawal (assessed through 24 hours) after 20%-alcohol drinking (7.6 g/kg) through 13 days, with provocation on the 14th day.  相似文献   
60.
Resting (CD38(low)) tonsillar B cells differentiate to express the centroblast-restricted CD77/globotriaosylceramide antigen on high-level engagement of CD154. As the CD38(low) population comprises both naive and memory subsets, we wished to compare the propensity of each to develop this germinal center phenotype; particularly as the capacity of memory B cells to re-enter afollicular reaction remains unclear. Resting B lymphocytes were therefore separated into CD27(-)IgA(-)IgG(-) and IgD(-) fractions to generate subsets enriched for naive and memory cells, respectively. Following stimulation via BCR and/or CD40 - surrogate signals for B cells engaged in T-dependent signaling - differences between the two subsets were seen in the kinetics and/or magnitude of responses such as entry into DNA synthesis, induction of the costimulatory molecules CD80 and CD86; up-regulation of CD23, and changes in BCL-6 mRNA expression. Nevertheless, naive and memory cells revealed a nigh identical capacity for acquiring CD77: both appeared equally sensitive in this regard, with high-level CD40 engagement via cell-bound CD154 being required for both subsets to achieve the hallmark centroblast phenotype. These findings suggest that, provided with the opportunity to encounter cell membrane CD154 in abundance, both naive and memory B cells display the potential to be diverted towards a germinal center pathway of differentiation.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号