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21.
AIM: To evaluate inflammatory activity in patients with Crohn’s disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy.METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn’s Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes.RESULTS: The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0% ± 10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P > 0.05, n = 20).CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.  相似文献   
22.
Hematopoiesis appears to be regulated, in part, by a balance between extracellular positive and negative growth signals. Transforming growth factor beta-1 (TGF-beta 1) has been shown to be a negative regulator of primitive hematopoietic cells. This study examined the direct effect of TGF-beta 1 on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC) in vitro. We previously reported a cell fractionation approach that includes the selection of low Hoescht 33342/low Rhodamine 123 (low Ho/Rh) cell fractions that are highly enriched for long-term repopulating cells (LTR-HSC) and also clone to a very high efficiency in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6: 90% to 100% of individually cultured low Ho/Rh cells formed high proliferative potential clones. This high cloning efficiency of an LTR-HSC enriched cell population enabled proliferation inhibition studies to be more easily interpreted. In this report, we show that the continuous presence of TGF-beta 1 directly inhibits the cell division of essentially all low Ho/Rh cells (in a dose-dependent manner) during their 0 to 5th cell division in vitro. Therefore, it follows that TGF-beta 1 must directly inhibit the proliferation of LTR-HSC contained within these low Ho/Rh cells. The time required for some low Ho/Rh cells to undergo their first cell division in vitro was also prolonged in the presence of TGF-beta 1. Furthermore, when low Ho/Rh cells were exposed to TFG-beta 1 for varying lengths of time before neutralization of the TGF-beta 1 by monoclonal antibody, the ability to form macroclones was markedly decreased after approximately 4 days of TGF-beta 1 exposure. In addition, 1 to 10 ng/mL of TGF-beta 1 resulted in a maintenance of high proliferative potential-colony-forming cell (HPP-CFC) during 8 days of culture compared with loss of HPP-CFC in cultures with no added TGF- beta 1. In conclusion, this study shows that TGF-beta 1 directly inhibits the initial stages of proliferation of LTR-HSC and appears to slow the differentiation of daughter cells of low Ho/Rh cells.  相似文献   
23.

Introduction

The Pietermaritzburg Metropolitan Trauma Service (PMTS) has run a systematic quality improvement programme since 2006. A key component included the development and implementation of an effective surveillance system in the form of an electronic surgical registry (ESR). This study used data from the ESR to review the incidence, spectrum and outcome of paediatric trauma in Pietermaritzburg, South Africa.

Methods

The ESR was reviewed, and all cases of paediatric trauma managed between 1 January 2012 and 30 July 2014 were retrieved for analysis.

Results

During the study period, 1,041 paediatric trauma patients (724 male, 69.5%) were managed by the PMTS, averaging a monthly admission of 36. The mean age was 10.9 years (standard deviation: 5.4 years). The mechanism of injury (MOI) was blunt trauma in 753 patients (72.3%) and penetrating trauma in 170 (16.3%). Pedestrian vehicle collisions accounted for 21% of cases and motor vehicle collisions for a further 11%. Intentional trauma accounted for 282 patients (27.1%) and self-inflicted trauma for 14 cases (1.3%). Ninety patients admitted to the intensive care unit and fifty-one required high dependency unit admission. There were 17 deaths, equating to an in-hospital mortality rate of 1.7%. A total of 172 children died on the scene of an incident. There were 35 road traffic related deaths, 26 suicides by hanging, 27 deaths from blunt assault and 23 deaths from penetrating assault. The overall mortality rate for paediatric trauma was 18.2%.

Conclusions

The ESR has proved to be an effective surveillance system and has enabled the accurate quantification of the burden of paediatric trauma in Pietermaritzburg. This has improved our understanding of the mechanisms and patterns of injury, and has identified a high incidence of intentional and penetrating trauma as well as road traffic collisions. These data can be used to guide strategies to reduce the burden of paediatric trauma in our environment.  相似文献   
24.
Hopper  KE; Semler  AD; Chapman  GV; Davey  RA 《Blood》1986,68(1):167-172
We show that human monocytes and platelets release considerable amounts of galactosyltransferase (GT) in serum-free culture as measured by the amount of incorporation of 3H-galactose into ovalbumin. Enzyme production was the greatest among medium-sized mononuclear cells separated by counter-current elutriation. The cells were adherent and positive for the monocyte-specific monoclonal antibody FMC-32. The activity in the monocyte fractions was not due to platelet contamination as shown from experiments in which platelets or platelet antigens were eliminated. Cell viability decreased by less than 3% during the overnight culture, and results from cell disruption experiments showed that the enzyme was not released from dead or dying cells. Cycloheximide inhibited release during 20 hours culture. Approximately 50% of the enzyme in the cell culture supernatant was pelletable at 105,000 g. Platelets released the enzyme more rapidly than did monocytes and were readily stimulated by thrombin to release more GT. Thrombin also increased monocyte GT activity after overnight incubation, but other stimulants, zymosan and lipopolysaccharide (LPS), decreased release. We conclude that GT is released into culture supernatants by platelets and by a subset of peripheral blood monocytes. These sources may account for a significant proportion of the serum enzyme and may be important in modification of extracellular carbohydrates during inflammation and coagulation.  相似文献   
25.
26.
Abstract

N-[3-(3,4-Dimethoxyphenyl)propanoyl]pyrrole (1) has been synthesized in three steps starting from veratraldehyde (2) with an overall yield of 66%.  相似文献   
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28.
In 1992–94 we screened 6315 students for coeliac disease (CD) by testing antigliadin antibodies (AGA) as the first-level investigation. We found 28 biopsy-proven coeliac patients who were invited to start the gluten-free diet (GFD). The aim of this study was a clinical and laboratory follow-up in these screening–detected coeliac adolescents. Patients were 17 females and 11 males with a mean age at diagnosis of 12.8 ± 1 years (range 11–14). Mean follow-up duration time was 23 ± 7 months (range 9–37). Twenty-three of the 28 screening-detected coeliac patients came to the control visit, 3 refused the follow-up and 2 subjects were not found. Twelve patients (52.2%) stated that they never ate any gluten-containing food, while 11 of them (47.8%) reported occasional transgressions to the diet. GFD acceptance was reported as good ( n = 6), moderate ( n = 11) or low ( n = 6). After starting the GFD, signs of improvement were seen in most patients, such as weight gain, increased height velocity and increased feeling of well-being. AGA (both IgG and IgA classes) and antiendomysium antibodies (AEA) were normal in 19 subjects, 2 cases had IgG-AG A and AEA positivity, 1 patient showed abnormal AGA and AEA levels, while isolated IgA-AGA positivity persisted in 1 case. This study shows that even silent CD cases can clinically benefit from the GFD. The consequences of occasional transgressions to the GFD remain unclear.  相似文献   
29.
Human milk has always been the reference parameter for the preparation of commercial formulae. The advent of more advanced technologies has enabled increasingly precise information on the composition of human milk to be obtained. Our knowledge in the field of carbohydrates also has improved considerably in the last few years following the pioneering studies of Montreuil (1, 2). From a quantitative point of view it has been demonstrated that in the different phases of lactation, in addition to lactose, human milk contains a consistent amount of oligosaccharides (about 20 g/1 in colostrum and 10–13 g/l in mature milk) (3, 4), whereas monosaccharides make up only about 1% of the total carbohydrates (4). More than 100 different types of oligosaccharides have been identified so far in human milk (5–7), mostly tri-octasaccharides (8). From a biochemical point of view, oligosaccharides are constituted by glucose, galactose, N -acetyl-glucosamine, fucose and sialic acid, and present a linear or branching structure (5). Little is known yet about their physiological role or metabolic fate (9); nevertheless, it has been demonstrated that, in addition to their nutritional function, they participate also in the regulation of the intestinal ecosystem, encouraging the growth of bifid flora (10) and contributing to the defense mechanisms against pathogens in various organs (11–13).  相似文献   
30.
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