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   129篇
  免费   28篇
耳鼻咽喉   1篇
儿科学   4篇
妇产科学   1篇
基础医学   20篇
口腔科学   4篇
临床医学   30篇
内科学   25篇
神经病学   23篇
外科学   12篇
综合类   1篇
预防医学   17篇
药学   9篇
肿瘤学   10篇
  2023年   1篇
  2022年   3篇
  2021年   8篇
  2020年   5篇
  2019年   6篇
  2018年   4篇
  2017年   4篇
  2016年   4篇
  2015年   8篇
  2014年   3篇
  2013年   3篇
  2012年   6篇
  2011年   11篇
  2010年   2篇
  2009年   5篇
  2008年   4篇
  2007年   4篇
  2006年   6篇
  2005年   5篇
  2004年   2篇
  2003年   5篇
  2002年   7篇
  2001年   3篇
  2000年   2篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1994年   1篇
  1993年   3篇
  1992年   1篇
  1991年   6篇
  1990年   1篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
  1980年   2篇
  1979年   5篇
  1976年   1篇
  1975年   2篇
  1971年   1篇
  1968年   1篇
  1967年   1篇
  1965年   3篇
排序方式: 共有157条查询结果,搜索用时 218 毫秒
1.
Background During the last decade, there has been a growing interest in outpatient support services for persons with intellectual disability (ID) and psychiatric and/or behavioural problems and their families. In this study, we explore the family burden that is associated with children or adults with ID and behavioural or psychiatric problems living at home. Method The research group consisted of 66 clients of In Casa, a project of outpatient treatment. Their average age is 18.97 years and their average IQ 55.37. The Reiss Screen for Maladaptive Behaviour (adults) or Reiss Scales for Children's Dual Diagnosis (children) and the Nijmegen Family Situation Questionnaire have been administered. Results About 62% of the children and 86% of the adults living at home and referred to In Casa have severe psychiatric or behavioural problems as measured by the Reiss scales. The dual diagnosis has a more negative impact on the family situation than the condition of ID only. Conclusion Parents consider the psychiatric or behavioural problems of their child to be an extra burden and feel it more difficult to raise and manage such a child. This impels them to change the situation and to call on the help of external services. Some methodological questions and the implications of the findings in terms of support needs are discussed.  相似文献   
2.
Estrous female rats display 'precopulatory behaviors' such as ear wiggling and hopping/darting when castrated males treated with testosterone propionate (TP) are placed in their vicinity and before copulatory interactions have taken place. Castrated males treated with estradiol benzoate (EB) do not elicit these precopulatory behaviors in advance of copulatory interactions. It therefore seemed of interest to study females' sexual behavior with castrated males treated with TP or EB when males or females had primary control over the temporal patterning of the behavior. Unrestrained sexual behavior (= male control) with EB-treated males was characterized by large numbers of intromissions and long periods of time preceding ejaculation, as compared with interactions with TP-treated males. The temporal pattern of sexual behavior did not change importantly when the males were tethered (= sexual behavior controlled by females). When given a choice between two sexually active castrated and tethered males, one treated with TP and the other with EB, estrous females 'preferred' EB-treated animals in various respects. Fewer interactions occurred with, and less time was spent in the vicinity of, TP-treated males over prolonged observation periods (115-135 min). The preference for EB-treated males disappeared, and TP- and EB-treated animals became equally attractive, when the vaginal opening of the female animals was covered with adhesive tape to prevent the occurrence of penile intromissions during mounting. It is concluded that female control over copulatory behavior does not necessarily change the females' sexual behavior.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.

Background  

Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP.  相似文献   
4.
Chemoattractants are generated at inflammatory loci that not only induce neutrophils (PMNs) to leave the vasculature but also stimulate PMNs to release potentially toxic agents (e.g., H2O2, O 2 or OH). We have recently demonstrated that endothelium releases adenosine which, when bound to a specific receptor on the PMN surface, inhibits release of toxic oxygen metabolites from stimulated PMN. To determine whether occupancy of adenosine receptors modulates generation and release of oxygen metabolites, we have studied the effect of 2-chloroadenosine on O 2 generation and O2 consumption in response to opsonized zymosan particles (STZ) and immune complexes (IC). 2-Chloroadenosine inhibits, in a dose-dependent fashion, Of generation by neutrophils that have been exposed to C3b-coated particles (STZ). Inhibition of Of generation is similar in the presence or absence of cytochalasin B (IC50=53 ±19 and 16 ±5nM, respectively,P=NS). Since occupancy of adenosine receptors might inhibit only externalization but not generation of oxygen metabolites, we studied the effect of 2-chloroadenosine on oxygen consumption by activated neutrophils. 2-Chloroadenosine inhibited O2 consumption stimulated by STZ and the surrogate bacterial chemoattractant FMLP; however, inhibition of O2 consumption varied with the presence or absence of cytochalasin B. In contrast, when neutrophils were stimulated by immune complexes, 2-chloroadenosine only minimally inhibited O 2 release and O2 consumption (10 ± 5 and 5 ± 4% inhibition, respectively). Thus, occupancy of adenosine receptors inhibits O2 consumption in parallel with inhibition of O 2 release. These results support the hypothesis that ingestion of complement-opsonized particles stimulates the respiratory burst by a mechanism different from that by which the respiratory burst is stimulated after occupancy of Fc receptors. Moreover, these observations suggest that endothelium, by releasing adenosine, prevent activated neutrophils from damaging the microvasculature at inflammatory loci. In contrast, deposition of immune complexes in vessel walls leads to vascular damage because endothelial cells are incapable of preventing attack by immune complex-stimulated neutrophils.This research was supported by grants from the U.S. Public Health Service (AI-10343 and HL29034) and the Veterans Administration.Dr. Cronstein is the recipient of a Clinical Investigator Award (K11-AR-01490) and was a fellow of the Arthritis Foundation. Dr. Broekman was an Established Investigator of the American Heart Association.  相似文献   
5.

Glioblastoma is associated with a poor prognosis. Even though survival statistics are well-described at the population level, it remains challenging to predict the prognosis of an individual patient despite the increasing number of prognostic models. The aim of this study is to systematically review the literature on prognostic modeling in glioblastoma patients. A systematic literature search was performed to identify all relevant studies that developed a prognostic model for predicting overall survival in glioblastoma patients following the PRISMA guidelines. Participants, type of input, algorithm type, validation, and testing procedures were reviewed per prognostic model. Among 595 citations, 27 studies were included for qualitative review. The included studies developed and evaluated a total of 59 models, of which only seven were externally validated in a different patient cohort. The predictive performance among these studies varied widely according to the AUC (0.58–0.98), accuracy (0.69–0.98), and C-index (0.66–0.70). Three studies deployed their model as an online prediction tool, all of which were based on a statistical algorithm. The increasing performance of survival prediction models will aid personalized clinical decision-making in glioblastoma patients. The scientific realm is gravitating towards the use of machine learning models developed on high-dimensional data, often with promising results. However, none of these models has been implemented into clinical care. To facilitate the clinical implementation of high-performing survival prediction models, future efforts should focus on harmonizing data acquisition methods, improving model interpretability, and externally validating these models in multicentered, prospective fashion.

  相似文献   
6.
Past research indicates that socioeconomic status (SES) accounts for differences in sensitivity across ethnic groups. However, comparatively little work has been conducted in Asia, with none examining whether ethnicity moderates the relation between SES and sensitivity. We assessed parenting behavior in 293 Singaporean citizen mothers of 6-month olds (153 Chinese, 108 Malay, 32 Indian) via the Maternal Behavioral Q-Sort for video interactions. When entered into the same model, SES (F(1,288) = 17.777, p < .001), but not ethnicity, predicted maternal sensitivity (F(2,288) = .542, p = .582). However, this positive relation between SES and sensitivity was marginally moderated by ethnicity. SES significantly positively predicted sensitivity in Chinese, but not Malay dyads. Within Indian dyads, SES marginally positively predicted sensitivity only when permanent residents were included in analyses. We discuss the importance of culture on perceived SES-associated stress. However, because few university-educated Malays participated, we also consider whether university education, specifically, positively influences sensitivity.  相似文献   
7.
Introduction: This study evaluated CD39 in a porcine model of balloon angioplasty and in plasma of patients undergoing percutaneous intervention. CD39 (E-NTPDase1), is the endothelial ecto-ADPase inhibiting platelet function via hydrolysis of released platelet ADP.Methods and Results: A recombinant soluble form of CD39 (solCD39) given intravenously to pigs had an elimination half life of 5–7 days, increased the bleeding time to an extent similar to aspirin, and inhibits platelet aggregation by > 90%. Platelet counts and clot retraction remained normal following solCD39 administration. In a pig model of acute coronary balloon injury, solCD39 resulted in non-statistically significant decreases in platelet (7.7 ± 1.4 versus 11.7 ± 3.4) and fibrin (3.5 ± 0.4 versus 4.2 ± 0.7) deposition ratios. Adding ex vivo to human platelet rich plasma (PRP) solCD39 produced nearly 100% inhibition of ADP-induced platelet aggregation. A dose-response effect of solCD39 on platelet aggregation induced by collagen or a thrombin receptor activating peptide (TRAPSFLLRN) was noted in PRP obtained from volunteers and patients receiving aspirin, clopidogrel or ticlopidine. SolCD39 also provided additional and complete inhibition of TRAP-induced platelet aggregation in PRP from patients who had received abciximab, aspirin and clopidogrel.Conclusions: SolCD39, a novel inhibitor of platelet activation and recruitment with a relatively long half-life appears to be well tolerated and is a potent inhibitor of ADP-, collagen-, or TRAP-induced platelet activation. Its potential use in percutaneous coronary intervention requires further study.Abbreviated Abstract. E-NTPDase1/CD39 is the endothelial ecto-ADPase responsible for inhibition of platelet function. A recombinant soluble form (solCD39) had an elimination half life of 5–7 days in pigs, elevated bleeding times similar to aspirin, did not affect clot retraction, and inhibited platelet aggregation by > 90%. When combined with standard heparin therapy in a pig model of acute coronary balloon injury, solCD39 resulted in a trend toward a decrease in platelet and fibrin deposition. SolCD39 added ex vivo to human platelet rich plasma yielded nearly 100% inhibition of ADP-induced platelet aggregation and provided further inhibition when combined with standard therapy.Supported in part by a Merit Review grant from the Department of Veterans Affairs (A.J.M., M.J.B.), and by National Institutes of Health grants HL 47073, HL 46403, and NS 41462 (A.J.M., M.J.B.) and by Immunex Corp., Seattle, WA.  相似文献   
8.
9.
10.
Purpose

Surgery in patients with non-functioning pituitary macroadenomas (NFMA) is effective in ameliorating visual function. The urgency for decompression, and preferred timing of surgery related to the preoperative severity of dysfunction is unknown.

Methods

Systematic review for evidence to provide clinical guidance for timing of surgical decompression of the optic chiasm, and a cohort study of 30 NFMA patients, in whom mean deviation (MD), and severity of visual dysfunction was assessed.

Results

Systematic review 44 studies were included with a total of 4789 patients. Postoperatively, visual field defects improved in 87.0% of patients, stabilized in 12.8% and worsened in 1.0%. Specific protocols regarding timing of surgery were not reported. Only seven studies (16.7%) reported on either the duration of visual symptoms, or diagnostic, or treatment delay.

Cohort study 30 NFMA patients (50% female, 60 eyes, mean age 58.5?±?14.8 years), had a median MD of???5.3 decibel (IQR???3.1 to???10.1). MD was strongly correlated with clinical severity (r?=????0.94, P?<?0.0001), and were used for severity of defects cut-off values: (1) normal?>????2 dB, (2) mild???2 dB to???4 dB, (3) moderate???4 to???8 dB, (4) severe???8 to???17 dB, (5) very severe?<????17 dB.

Conclusion

Surgical decompression is highly effective in improving visual function. Uniform, quantitative grading of visual dysfunction was lacking. MD is a promising quantitative outcome measure. We provide recommendations for the evaluation of timing of surgery, considering severity of visual impairment, which will need further validation based on expert clinical practice.

  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