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1.
Edgewise compression response of a composite structural insulated panel (CSIP) with magnesium oxide board facings was investigated. The discussed CSIP is a novel multifunctional sandwich panel introduced to the housing industry as a part of the wall, floor, and roof assemblies. The study aims to propose a computational tool for reliable prediction of failure modes of CSIPs subjected to concentric and eccentric axial loads. An advanced numerical model was proposed that includes geometrical and material nonlinearity as well as incorporates the material bimodularity effect to achieve accurate and versatile failure mode prediction capability. Laboratory tests on small-scale CSIP samples of three different slenderness ratios and full-scale panels loaded with three different eccentricity values were carried out, and the test data were compared with numerical results for validation. The finite element (FE) model successfully captured CSIP’s inelastic response in uniaxial compression and when flexural action was introduced by eccentric loads or buckling and predicted all failure modes correctly. The comprehensive validation showed that the proposed approach could be considered a robust and versatile aid in CSIP design.  相似文献   
2.
We have shown previously that the chemoprotective activity of diallyl disulfide (DADS), a naturally occurring anticancer agent in garlic, against benzo[a]pyrene (BP)-induced forestomach carcinogenesis in mice correlates strongly with its inductive effects on the expression of Pi class glutathione (GSH) transferase mGSTP1-1. The present structure-activity relationship studies were designed to define the role of allyl groups and the disulfide chain in mGSTP1-inducing activity of DADS. Hepatic mGSTP1 mRNA levels rose rapidly upon treatment of mice with DADS, reached a maximum between 12 and 24 h (< or =5.7-fold induction) and fell to control levels by 48 h after DADS treatment. Induction of mGSTP1 mRNA in the forestomach was maximal between 6 and 12 h after DADS treatment (< or =4.7-fold induction). The mGSTP1 mRNA expression was either unaltered (liver) or moderately increased (forestomach) upon treatment of mice with dipropyl disulfide (DPDS), which is a naturally occurring saturated analog of DADS. These results indicated that the allyl groups are critical for the mGSTP1-inducing activity of DADS. A statistically significant increase in the expression of mGSTP1 mRNA was also observed in the liver and forestomach of mice treated with diallyl monosulfide (DAMS), albeit to a much lesser extent compared with DADS. These results indicated that the oligosulfide chain length in garlic organosulfides (OSCs) is equally important for their mGSTP1-inducing activity. The role of the disulfide chain in DADS-mediated induction of mGSTP1 was further investigated by testing a pair of alkadienes (1,7-octadiene and 1,8-nonadiene) having structural similarity to DADS. Both DADS and the alkadienes carry allyl groups at both ends of a linear molecule and the distance between the allylic carbon atoms is similar in both compounds, but the central disulfide chain of DADS is replaced with an alkyl chain in the alkadienes. The alkadienes were either ineffective or moderately active in increasing mGSTP1 expression. In conclusion, the results of the present study clearly indicate that the presence of terminal allyl groups as well as the central disulfide chain is required for maximum induction of mGSTP1 in vivo by garlic-derived OSCs.  相似文献   
3.
A total of 6193 patients treated for uterine cervix cancer was studied by a collaborative study, aiming to compare the applicability of the TNM versus FIGO clinical staging systems. Retrospective assays of gynecological status were performed. It was found that the FIGO classification system is superior to the TNM system concerning uterine cervix cancer in the aspects of simplicity, recording procedures, and prognostic value.  相似文献   
4.
A hemoregulatory peptide (HP5b) associated with mature human granulocytes has been investigated for inhibitory effects on murine hemopoietic stem cells in vitro. Both highly purified peptide from natural sources and a synthetic analog peptide have been investigated in parallel. Strong inhibitory effects were found on myelopoietic colony formation in the dose range 10(-13)-10(-5) mol/l. On exceeding this dose, the inhibitory effect disappeared. Moderate to slight inhibitory effects on erythroid colony formation (BFU-E and CFU-E) from adult animals were only seen in 1,000 X the optimal doses for myelopoiesis. No effect was found on CFU-E from fetal liver. The peptide thus has a selective effect on myelopoiesis in a certain dose range. A regulatory mechanism for the peptide on hemopoiesis is proposed.  相似文献   
5.
Summary In previous studies it had been found that C 57 Bl/6 marrow cells, normally resistant to infection by the Friend virus (FV-P), became susceptible after their transplantation into lethally irradiated leukemic DBA/2 mice. This loss of FV-P resistance was further analyzed and spleen weight and the number of erythropoietin-(Ep)-independent CFU-E in bone marrow and spleen were measured as the result of successful FV-P infection. C 57 Bl/6 marrow was infected shortly before and in intervals after either isogeneic transplantation or transplantation into lethally irradiated DBA/2 hosts. After isogeneic transplantation there was some susceptibility for FV-P and this seemed to correlate with the regenerative activity of BFU-E at the time of infection. However, there was no difference in the BFU-E kinetics between normal DBA/2 and C 57 Bl/6 mice. C 57 Bl/6 were further pretreated by bleeding, irradiation with 150 R, injection of hydroxyurea and of endotoxin. After hydroxyurea treatment there was an increased proportion of BFU-E in S-phase, but only endotoxin, which did not alter the BFU-E kinetics after 48 h, made C 57 B1/6 mice susceptible to FV-P infection. These results suggest that the proliferative activity of BFU-E might be important for successful FV-P infection and induction of Ep-independent erythropoiesis but also other conditions regulate the resistance or susceptibility of a mouse strain.Supported by the Deutsche Forschungsgemeinschaft (SFB 112) and Stiftung Volkswagenwerk  相似文献   
6.
The FV-replicating target cell characterized in this study is an erythroid precursor cell, as shown by its response to bleeding and hypertransfusion. The target cell is not identical with the BFU-E compartment as demonstrated by different model velocities and different cell cycle characteristics as compared to BFU-E. Different sensitivity of FV-target cells and CFU-E to AMD, differences in the growth kinetics of both cell populations in bone marrow and spleen of mice after bleeding, and large quantitative differences of both cell populations in hemopoietic organs, suggest only partial identity or non-identity of these two cell types. Finally it is shown that spleen colonies originating from FV-infected target cells are a primary erythroleukemic lesion, since they contain more Ep-independent CFU-E than do intercolony areas of the spleen.  相似文献   
7.
Erythroid burst-forming units (BFU-E) from canine bone marrow and peripheral blood could be grown in methylcellulose in the presence of an appropriate batch of fetal calf serum (FCS), transferrin, and erythropoietin (Epo). However, improved colony formation (size and number of bursts) was obtained when serum from total body irradiated dogs was present in the culture. This serum, obtained from dogs at day 9 after total body irradiation with a dose of 3.9 Gy, reduced markedly the Epo requirement of BFU-E. Furthermore, it allowed the omission of FCS from the culture medium if cholesterol and bovine serum albumin (BSA) were used as FCS substitutes. BFU-E concentrations were found to be rather different in the peripheral blood and in bone marrow samples from different sites (i.e., iliac crest, sternum, and humerus) of normal beagles. The studies further show that canine bone marrow BFU-E can be cryopreserved in liquid nitrogen.  相似文献   
8.
Of 8191 patients with invasive carcinoma of the cervix treated from 1950 to 1970 in the Institute of Oncology in Warsaw, 327 cases (3.9%) were associated with pregnancy. In 63 patients, the disease was diagnosed during pregnancy and in 264 patients, within 1 year after abortion (83 patients) or after delivery (181 patients). A close relationship between the advancement of cervical cancer and gestation was found. The percentage of patients with Stages III and IV cancer was lowest in patients treated in the first trimester of pregnancy (2.5%) and highest in those treated after delivery (44.2%). It was found that the stage distribution of cancer and the advancement of gestation were related to the age of the patient. In the youngest patients (20–29 years old), there was the highest percentage of patients treated in Stage III (38.6%) and after delivery (72.8%). The results of treatment were closely connected with the stage distribution and the period of gestation. While the results were quite satisfactory in patients treated in the first trimester (73.2% of survivors) and after abortion (63.9%), the 5-year survival rate was only 36.5% in patients treated after delivery. In relationship to the age of the patients, the results of treatment in particular stages of cancer were worst in the youngest group, especially in Stage III (11% of survivors).  相似文献   
9.
G-banding analysis was carried out in 45 mice after exposure to the leukemogen butylnitrosourea (BNU). Of 27 animals without clinical signs of leukemia, 2 had chromosomal rearrangements (7%) while, of 18 leukemic mice, 5 showed abnormal karyotypes (28%). The chromosomal abnormalities were not random and showed preferential changes of chromosomes Nos. 14 and 15. The organ distribution of the chromosomal abnormalities showed a preferential involvement of the thymus with a secondary presence of chromosome anomalies in peripheral lymphoid organs and the bone marrow. The findings are discussed in relation to the recent reports on the specificity of trisomy 15 in murine leukemia and lymphoma.  相似文献   
10.
The radiosensitivity of the early erythroid progenitor cells (BFU-E) and the progenitor cells of the stroma (CFU-F) in canine bone marrow was studied under steady-state conditions by in vitro irradiation with 280 kV X-rays. The dose-effect relationship for colony formation was determined for BFU-E obtained from the iliac crest marrow, and for CFU-F in bone marrow collected from the iliac crest and the humerus of adult beagles. The BFU-E were adequately stimulated with serum from lethally irradiated dogs to obtain a source of BPA (burst-promoting activity). The BFU-E proved to be extremely radiosensitive, and the survival curve was exponential (D0 = 15.3 +/- 1.8 cGy). We showed that buffy-coat leukocytes separated from bone marrow leukocytes obtained by aspiration were an optimum source of CFU-F. A curve was fitted to the data obtained for CFU-F obtained from the iliac crest or the humerus, resulting in D0 = 241 +/- 38 cGy and an extrapolation number n = 1.38 +/- 0.62 or D0 = 261 +/- 40 cGy and n = 1.04 +/- 0.42, respectively. According to these findings, and other published data, we conclude that the canine bone marrow BFU-E are presently the most radiosensitive hemopoietic cells detected among all hemopoietic cells of different mammals.  相似文献   
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