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排序方式: 共有862条查询结果,搜索用时 15 毫秒
1.
P. Andersson K. LeBlanc B-. Eriksson J. Samuelsson 《European journal of haematology》1997,59(5):310-317
Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34+ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder. 相似文献
2.
A car-borne NaI(Tl) spectrometric system was used together with a 137Cs source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting method was also developed and evaluated. Results from the curve fitting method showed inferior ability to find the source compared to the PSC method. However, it can be a useful complementary tool, for characterisation of the source shielding, and estimation of the distance from the road. 相似文献
3.
G Samuelsson M H Farah P Claeson M Hagos M Thulin O Hedberg A M Warfa A O Hassan A H Elmi A D Abdurahman 《Journal of ethnopharmacology》1992,37(2):93-112
Thirty-five plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects. 相似文献
4.
Allergic reactions to raw, pasteurized, and homogenized/pasteurized cow milk: a comparison 总被引:1,自引:0,他引:1
Five children aged 12-40 months with IgE-mediated adverse reactions to cow milk (immediate onset clinical pattern of cow milk allergy) were orally challenged double-blind in random order with three different milk preparations processed from the same batch of milk 1) raw untreated cow milk, 2) pasteurized cow milk, 3) homogenized and pasteurized cow milk, and 4) Nutramigen (a commercial hypoallergenic infant formula based on hydrolysed casein) as placebo. Skin prick tests with the same preparations were also performed. On oral challenge the three different processed milk types provoked significant and similar allergic reactions in each child, and no adverse reactions followed the challenge with placebo (Nutramigen). Skin prick test with the same milk products were positive in all children and comparable to the results with an extract of purified raw cow milk protein (Soluprick), whereas Nutramigen did not elicit any skin reactions. A tendency towards a lower threshold of reaction and larger skin reactions induced by the processed milk preparations might indicate an increased ability of pasteurized and homogenized/pasteurized milk to evoke allergic reactions in patients allergic to milk. 相似文献
5.
6.
P. Appelros M. Samuelsson S. Karlsson-Tivenius M. Lokander A. Terént 《European journal of neurology》2007,14(8):890-894
Registration of all hospitalized stroke patients is practiced in Sweden in order to assess care quality. Data in this register, Riks-Stroke (RS), may be biased due to incomplete registration. The purpose of this paper was to report changes in stroke outcome in relation to fluctuations in registration. Patients registered in RS at a hospital during the period 1994–2005 were analyzed. Case fatality at 28 days, living conditions, and activities of daily living (ADL) performance at 3 months were correlated to the number of patients registered and follow-up frequency. A total of 4994 stroke cases were registered during the period. A high annual registration rate was significantly correlated to a high case fatality ratio. A low annual follow-up rate was associated with a low proportion of patients living in their own home without any need of help. Quality parameters are sensible for selection bias, which make them difficult to compare over time and between hospitals. We suggest that by weighing outcome data against stroke severity, safer conclusions may be drawn. Additionally, hospitals considering setting up quality registers should make every effort to attain complete case ascertainment at all times, including patients managed outside the hospital, in order to avoid selection bias. 相似文献
7.
Nonacid plasma glycolipids from Lewis-negative individuals of nonsecretor, partial-secretor and secretor phenotypes were prepared and separated by thin-layer chromatography and immunostained with radiolabelled Lewis antibodies. Lewis-positive plasma and intestinal epithelial cell glycolipids from Caucasians representing the four recognized Lewis and secretor combined phenotypes were used as controls. By presenting these purified total glycolipids in a cell-free environment to Lewis antibodies we were able to demonstrate the presence of small amounts of Lewis antigens in Lewis-negative individuals. It is shown that lactotetraosylceramide and extended precursor glycolipids are present in all Le(a–b–) nonsecretors. Lea was detected in 1 of the 3 Le(a–b–) nonsecretor plasmas and in the intestinal sample of the same phenotype. Lactotetraosylceramide was absent but H type 1 and Leb were both present in all group O Le(a–b–) secretors, and extended H type 1 reactive structures were also found in the partial secretor. These results clearly demonstrate that although the Lewis-negative phenotype exists at the serological level, this phenotype is not an 'all-or-nothing' phenomenon at the chemical level. We also show that in the presence of reduced fucosyltransferase activity, increased elongation of the precursor chain occurs, which allows us to postulate that fucosylation of the precursor prevents or at least markedly reduces chain elongation. 相似文献
8.
Body composition in patients treated with peritoneal dialysis 总被引:2,自引:1,他引:1
Johansson A; Samuelsson O; Haraldsson B; Bosaeus I; Attman P 《Nephrology, dialysis, transplantation》1998,13(6):1511-1517
Background: Malnutrition is a common complication in
uremia and during maintenance dialysis. Several factors contribute to its
development. Different modes of dialysis treatment may differ in their
effects on nutritional status. Methods: In order to
analyse the nutritional consequences of peritoneal dialysis (PD), body
composition analyses were performed in PD patients between February 1993
and March 1996. Body cell mass (BCM) was estimated from measurements of
total body potassium (TBK) in a whole-body counter. Total body water (TBW)
was determined by measurement of tritiated water. Body fat (BF) was
calculated from body weight (BW), TBK and TBW. Observed values were related
to predicted (o/p) derived from local population studies.
Results: Sixty patients were repeatedly investigated
during the study period. Of these, 34 were investigated during the first
year of PD. At the start of dialysis, TBK o/p was 0.94 and BF o/p 0.76. No
change in body composition was seen during the observation period in the
group as a whole. However, within the group individual changes in BW were
strongly correlated with individual changes in BF (r=0.66, P=0.0001).
Twenty-six patients were examined during the second and third year of PD.
In this group, BW o/p remained constant over time. However, there was a
small but significant decline of TBK o/p and a concomitant increase of BF
o/p (P<0.05). No correlation was observed between changes in TBK and
changes in serum albumin. Conclusions: The results of
this study indicate, that there may be a risk for further reduction of body
cell mass during long-term PD treatment, while body energy stores are
maintained or even increased. 相似文献
9.
Anita Samuelsson MSc Monica Ahlmn MD Marianne Sullivan PhD 《Patient education and counseling》1993,20(2-3):77-91
During the last few years, studies have revealed that the need for psychosocial support and concrete social services are great in the early stages of the treatment of rheumatic diseases. The ability to keep a job, to do household chores, to participate in leisure activities and to maintain social relations is clearly impaired. Anxiety and depression are not unusual and often associated with weak support from relatives, loneliness and disturbed family relations. Nevertheless, the patients report resilience and determination to cope with the impacts of illness. Crisis intervention, vocational guidance and counselling about problems concerning the disease should be available and offered to the patients. As the patients seem to be unaccustomed to talking about their psychosocial problems, an empathetic and information-seeking attitude on the part of the health care staff is essential. 相似文献
10.
Heart rate (HR) response to step-function and ramp-function (20 W/min) work tests was compared in 12 healthy subjects. For a given power output (P), HR was substantially lower in the ramp tests. The HR difference increased with power output and increasing difference in work time between the test types. The HR difference can be explained in terms of a drift component (which accounts for 1/3 of the difference) and a lag component (2/3). As a consequence of the HR differences, P for a given HR is higher in ramp tests. Work capacity expressed, for example as P170, can be determined in ramp tests, and the result can be translated to step-function P170. The precision in this translation is markedly improved if a steady-state period is incorporated into the ramp test. 相似文献