全文获取类型
收费全文 | 324篇 |
免费 | 15篇 |
国内免费 | 13篇 |
专业分类
儿科学 | 13篇 |
妇产科学 | 5篇 |
基础医学 | 43篇 |
口腔科学 | 12篇 |
临床医学 | 29篇 |
内科学 | 79篇 |
皮肤病学 | 7篇 |
神经病学 | 4篇 |
特种医学 | 71篇 |
外科学 | 27篇 |
综合类 | 10篇 |
预防医学 | 6篇 |
眼科学 | 2篇 |
药学 | 22篇 |
中国医学 | 3篇 |
肿瘤学 | 19篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 5篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 14篇 |
2012年 | 14篇 |
2011年 | 12篇 |
2010年 | 20篇 |
2009年 | 18篇 |
2008年 | 4篇 |
2007年 | 10篇 |
2006年 | 10篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 4篇 |
1999年 | 3篇 |
1998年 | 22篇 |
1997年 | 17篇 |
1996年 | 18篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1993年 | 8篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 12篇 |
1985年 | 10篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
排序方式: 共有352条查询结果,搜索用时 31 毫秒
121.
G Cheng ; DS Chiu ; AS Chung ; HF Wong ; MW Chan ; YK Lui ; FM Choy ; JC Chan ; AH Chan ; ST Lam ; TC Fan 《Transfusion》1996,36(4):347-350
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up. 相似文献
122.
Baboon envelope pseudotyped lentiviral vectors efficiently transduce human B cells and allow active factor IX B cell secretion in vivo in NOD/SCIDγc‐/‐ mice 下载免费PDF全文
123.
Vandendriessche JB Vandorpe B Coelho-e-Silva MJ Vaeyens R Lenoir M Lefevre J Philippaerts RM 《Pediatric exercise science》2011,23(4):504-520
Discussions of growth and motor performance of children are often set in the context of physical fitness. Although there is a clear theoretical concept or definition of fitness comprising motor coordination, the latter is not systematically considered. This study determined to what extent the variance in motor coordination might be explained by morphological and fitness characteristics. To postulate understanding of this association during childhood, 613 boys aged 7-11 years completed the morphological measurements, the K?rperkoordinationstest für Kinder (KTK) and different fitness tests. The results demonstrated a substantial interrelationship among morphology, fitness and motor coordination in elementary school boys. The magnitude of explained variance and the loadings of the canonical correlation between the several constructs are strongly pronounced during childhood indicating that these constructs should be well considered given their contribution to a child's general development. 相似文献
124.
Fion L Sung Yan Cui Edwin P Hui Lili Li Thomas KS Loh Qian Tao Anthony TC Chan 《American journal of cancer research》2014,4(6):789-800
Lysyl oxidase (LOX) is an oxidative enzyme known to initiate the cross-linking of collagens and elastin, and suggested recently as a tumor suppressor for several tumor types including lung, pancreatic and gastric cancers. Previously we showed that LOX is strongly induced upon hypoxia in nasopharyngeal carcinoma (NPC) cell lines CNE2 and HONE1 but only slightly in HK1 and not in C666-1. Here, we further studied the regulatory mechanism and functions of LOX in NPC. LOX is widely expressed in human normal tissues with variations in expression levels. LOX was expressed in most NPC cell lines except for C666-1, while HK1 and FaDu (laryngeal cancer) only expressed low level of LOX. Methylation analysis showed that the LOX promoter was methylated in C666-1 and partially methylated in HK1. After demethylation with 5-aza-2’-deoxycytidine, LOX expression was reactivated along with increased unmethylated alleles. LOX promoter methylation was detected in 42/49 (85.7%) of NPC primary tumors but only 3/16 (18.75%) of nose swab samples from NPC patients. LOX overexpression reduced the clonogenicity and cell growth of NPC cells, and also inhibited the migration and invasion of the NPC cells. Carbonic anhydrase IX (CA9) mRNA level was obviously decreased in HK1 cells after transfection with LOX. The elevation of CA9 protein upon hypoxia was inhibited in LOX-transfected HK1 cells. The protein levels of an apoptosis marker cPARP were increased in LOX-transfected HK1 cells upon hypoxia treatment. Our data showed that silencing or down-regulation of LOX in NPC was due to its promoter methylation and LOX acts as a tumor suppressor in NPC. LOX silencing would facilitate NPC cells to escape from hypoxia-induced apoptosis and maintains a malignant and metastatic phenotype. 相似文献
125.
Vermeulen Windsant IC de Wit NC Sertorio JT Beckers EA Tanus-Santos JE Jacobs MJ Buurman WA 《Critical care (London, England)》2012,16(3):R95-11
ABSTRACT: INTRODUCTION: The increasing number of reports on the relation between transfusion of stored red blood cells (RBCs) and adverse patient outcome has sparked an intense debate on the benefits and risks of blood transfusions. Meanwhile, the pathophysiological mechanisms underlying this postulated relation remain unclear. The development of hemolysis during storage might contribute to this mechanism by release of free hemoglobin (fHb), a potent nitric oxide (NO) scavenger, which may impair vasodilation and microcirculatory perfusion after transfusion. The objective of this prospective observational pilot study was to establish whether RBC transfusion results in increased circulating fHb levels and plasma NO consumption. In addition, the relation between increased fHb values and circulating haptoglobin, its natural scavenger, was studied. METHODS: Thirty patients electively received 1 stored packed RBC unit (n = 8) or 2 stored packed RBC units (n = 22). Blood samples were drawn to analyze plasma levels of fHb, haptoglobin, and NO consumption prior to transfusion, and 15, 30, 60 and 120 minutes and 24 hours after transfusion. Differences were compared using Pearson's chi-square test or Fisher's exact test for dichotomous variables, or an independent-sample t test or Mann-Whitney U test for continuous data. Continuous, multiple-timepoint data were analyzed using repeated one-way analysis of variance or the Kruskall-Wallis test. Correlations were analyzed using Spearman or Pearson correlation. RESULTS: Storage duration correlated significantly with fHb concentrations and NO consumption within the storage medium (r = 0.51, P < 0.001 and r = 0.62, P = 0.002). fHb also significantly correlated with NO consumption directly (r = 0.61, P = 0.002). Transfusion of 2 RBC units significantly increased circulating fHb and NO consumption in the recipient (P < 0.001 and P < 0.05, respectively), in contrast to transfusion of 1 stored RBC unit. Storage duration of the blood products did not correlate with changes in fHb and NO consumption in the recipient. In contrast, pre-transfusion recipient plasma haptoglobin levels inversely influenced post-transfusion fHb concentrations. CONCLUSION: These data suggest that RBC transfusion can significantly increase post-transfusion plasma fHb levels and plasma NO consumption in the recipient. This finding may contribute to the potential pathophysiological mechanism underlying the much-discussed adverse relation between blood transfusions and patient outcome. This observation may be of particular importance for patients with substantial transfusion requirements. 相似文献
126.
Di Matteo M Belay E Chuah MK Vandendriessche T 《Expert opinion on biological therapy》2012,12(7):841-858
INTRODUCTION: The continuous improvement of gene transfer technologies has broad implications for stem cell biology, gene discovery, and gene therapy. Although viral vectors are efficient gene delivery vehicles, their safety, immunogenicity and manufacturing challenges hamper clinical progress. In contrast, non-viral gene delivery systems are less immunogenic and easier to manufacture. AREAS COVERED: In this review, we explore the emerging potential of transposons in gene and cell therapy. The safety, efficiency, and biology of novel hyperactive Sleeping Beauty (SB) and piggyBac (PB) transposon systems will be highlighted for ex vivo gene therapy in clinically relevant adult stem/progenitor cells, particularly hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), myoblasts, and induced pluripotent stem (iPS) cells. Moreover, efforts toward in vivo transposon-based gene therapy will be discussed. EXPERT OPINION: The latest generation SB and PB transposons currently represent some of the most attractive systems for stable non-viral genetic modification of primary cells, particularly adult stem cells. This paves the way toward the use of transposons as a non-viral gene therapy approach to correct hereditary disorders including those that affect the hematopoietic system. The development of targeted integration into "safe harbor" genetic loci may further improve their safety profile. 相似文献
127.
Vandendriessche JB Vandorpe BF Vaeyens R Malina RM Lefevre J Lenoir M Philippaerts RM 《Pediatric exercise science》2012,24(1):113-128
Socioeconomic status (SES) is often indicated as a factor that influences physical activity and associated health outcomes. This study examined the relationship between SES and sport participation, morphology, fitness and motor coordination in a sample of 1955 Flemish children 6-11 years of age. Gender, age and SES-specific values for morphologic dimensions, amount and type of sport participation and fitness and motor coordination tests were compared. SES was positively and significantly associated with sport participation and sports club membership in both sexes. Although differences were not consistently significant, morphologic dimensions and tests of fitness and motor coordination showed a trend in favor of children from higher SES. The results suggest that public and local authorities should consider providing equal opportunities for children in all social strata and especially those in the lower SES to experience the beneficial effects of sport participation through which they can enhance levels of physical fitness and motor coordination. 相似文献
128.
Erika M Santos Maria TC Lourenço Benedito M Rossi 《Hereditary cancer in clinical practice》2011,9(1):1-6
Background
Risk perception is considered a motivating factor for adopting preventive behaviors. This study aimed to verify the demographic characteristics and cancer family history that are predictors of risk perception and to verify if risk perception is a predictor of colonoscopy adherence.Methods
Individuals with a family colorectal cancer history as indicated by a proband with cancer were interviewed by telephone. They responded to a questionnaire covering demographic characteristics, colonoscopy history and four questions on risk perception. Tests of multiple linear regression and logistic regression were used to identify associations between dependent and independent variables.Results
The 117 participants belonged to 62 families and had a mean age of 45.2 years. The majority of these individuals were female (74.4%) and from families who met the Amsterdam Criteria (54.7%). The average risk perception was 47.6%, with a median of 50%. The average population perception of individual risk was 55.4%, with a median of 50%. Variables associated with a higher risk perception were age, gender, religion, school level, income, and death of a family member. The variable predicting colonoscopy was receiving medical information regarding risk (odds ratio OR 8.40).Conclusions
We found that family cancer history characteristics (number of relatives with cancer, risk classification) are associated with adequate risk perception. Risk perception does not predict colonoscopy in this sample. The only variable that predicted colonoscopy was receiving medical information recommending screening. 相似文献129.
A Timmermans S Veersema TC van Kerkvoorde LF van der Voet BC Opmeer MY Bongers BWJ Mol 《BJOG : an international journal of obstetrics and gynaecology》2009,116(10):1391-1395
We describe the design of a randomised controlled trial to evaluate the efficacy of endometrial polyp removal in women with postmenopausal bleeding. We designed a trial in which patients with postmenopausal bleeding and endometrial thickness >4 mm undergo hysteroscopy. If during hysteroscopy an endometrial polyp was diagnosed, patients were asked to participate in this trial and after informed consent allocated to immediate removal of the polyp or expectant management. This trial suffered from lack of recruitment related both to doctors seeking for informed consent as well as to patients' unwillingness to participate in this trial. However, a randomised controlled trial on this subject is still necessary to evaluate the efficacy of uterine cavity evaluation in the diagnostic work-up of women with postmenopausal bleeding, focussing on benign pathology. Therefore, we propose an alternative design, which might be more feasible. 相似文献
130.
Vincent Tchana-Sato Didier Ledoux Katrien Vandendriessche Johan Van Cleemput Gregory Hans Arnaud Ancion Bjorn Cools Philippe Amabili Olivier Detry Paul Bernard Massion Josee Monard Marie-Hélène Delbouille Bart Meyns Jean Olivier Defraigne Filip Rega 《The Journal of heart and lung transplantation》2019,38(10):1112-1115