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1.
Spermidine/Spermine N-Acetyltransferase, a New Biochemical Marker for Epithelial Proliferation in Rat Bladder 总被引:4,自引:4,他引:0
Isao Matsui-Yuasa Shuzo Otani Yoshihisa Yano Nobuyasu Takada Masa-Aki Shibata Shoji Fukushima 《Cancer science》1992,83(10):1037-1040
We examined the activity of spermidine/spermine N 1 -acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis. 相似文献
2.
B.-O. NILSSON M. GOMEZ R. SANTIAGO CARRILHO I. NORDSTR
M P. HELLSTRAND 《Acta physiologica (Oxford, England)》1995,154(3):355-365
Effects of the naturally occurring polyamine spermine on electrical and contractile properties of the rat portal vein were studied. 1 mM spermine nearly abolished spike activity and spontaneous contractions and decreased the intracellular Ca2+ concentration ([Ca2+],). The phasic force responses to 0.1 and 1 μM phenylephrine were partially inhibited, but not the sustain plateau contraction caused by 5 /IM phenylephrine. The Ca2+-force relation in high-K+ (128 mM)-depolarized veins was shifted to the right, EC50 for Ca2+ increasing from 0.50 ± 0.03 mM (control, n= 8) to 0.65 ± 0.06 and to 0.94 ± 0.03 at 1 (n – 4) and 10 (n = 3) mM spermine, respectively. However, at a Ca2+ concentration of 2.5 mM, giving maximal force, there was no effect of spermine (1 mM) on either force or [Ca2+],. Whereas extracellular spermine thus reduced contractile activity at moderate levels of stimulation, increased intracellular concentration of spermine potentiated the force response to Ca2+. Intracellular loading of spermine by reversible permeabilization increased its concentration by 2–3 times. The spontaneous activity and response to phenylephrine were unchanged. However, the Ca2+-force relation of depolarized veins was shifted to the left, EC50 decreasing from 0.51 ± 0.04 mM in controls (n= 7) to 0.36 ± 0.02 mM in the loaded veins (n= 9). Spermine increased Ca2+-activated force in portal veins permeabilized with β-escin. The degree of potentiation was consistent with observed effects in spermine-loaded intact veins. The results suggest that spermine at physiological intracellular concentration may contribute to the determination of Ca2+ sensitivity in vascular smooth muscle cells. 相似文献
3.
4.
目的:了解疟原虫的多胺代谢与咯萘啶(PND)抗药性的关系。方法:感染伯氏疟原虫ANKA株(PS)和由该株培育的中抗PND品系(PRA)及高抗PND品系(PRB)的昆明株小鼠于腹腔接种(ip)后d7取血,经薄层层析后用荧光分光光度法测定正常RBC、PS、PRA和PRB感染RBC的丁二胺(PTC)、精脒(SPD)和精胺(SPM)量。另有感染PS和PRB的小鼠于ip后d6分别1次灌胃(ig)PND5mg/kg和10mg/kg,d7取血,按上述方法测定给药后感染RBC的多胺量,并与不给药组比较。结果:PS感染RBC的多胺量均明显高于未感染疟原虫的正常RBC,而感染PRA和PRB的RBC多胺量又显著高于PS感染RBC,且多胺量的增高与抗性程度有关。经PND治疗后PS感染RBC的SPD和SPM较未治疗组显著下降,而PRB感染RBC则未见明显变化。结论:伯氏疟原虫对PND的抗药性与其多胺代谢有关。 相似文献
5.
Dr. Jill Palmer Smith MD Scott T. Kramer BA Laurence M. Demers PhD 《Digestive diseases and sciences》1993,38(3):520-528
The effect of difluoromethylornithine (DFMO), a specific inhibitor of ornithine decarboxylase activity, was evaluatedin vivo andin vitro on the growth of a gastrin-sensitive human colon carcinoma (WiDr).In vivo, mice bearing the tumor treated with pentagastrin had larger tumors with higher ornithine decarboxylase activity and polyamine content (P<0.05) than mice not treated with pentagastrin. Difluoromethylornithine treatment significantly decreased ornithine decarboxylase in both the pentagastrin-treated and the untreated animals; however, DFMO had no effect on tumor volume, weight, protein, or DNA content. In cell culture, gastrin treatment increased WiDr cell number and [3H]thymidine incorporation in the presence or absence of serum. In serum-free conditions, however, gastrin stimulated cell growth without concomitantly increasing ODC activity. DFMO, on the other hand, decreased both ODC activity and growth. These studies suggest that the trophic effect of gastrin on WiDr human colon cancer is independent of ODC activity. Since gastrin treatment increased ODC activityin vivo, gastrin may interactin vitro with other factors present in serum that can alter ODC activity.Supported by NIH First CA50303 and American College of Physicians Research and Teaching Award to Dr. Smith. 相似文献
6.
Makhloufi Zoulikha Qingqing Xiao George Frimpong Boafo Marwa A.Sallam Zhongjian Chen Wei He 《药学学报(英文版)》2022,12(2):600-620
The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic. 相似文献
7.
<正>Snyder-Robinson综合征(SRS)是一种X连锁智力障碍性疾病,由精胺合酶(SMS)基因突变引起,主要表现为智力障碍、肌张力低下、骨质疏松等。目前国内尚未见报道。本文报道1例新生儿期SRS的临床表现及基因测序结果,以加强临床医生对本病的认识。1病历资料患儿男,出生后3 h。因“出生后3 h发现面部不对称、不完全腭裂”于2020-07-27入山东第一医科大学第一附属医院新生儿科, 相似文献
8.
Potent Analgesia Induced in Rats by Combined Action at PCP and Polyamine Recognition Sites of the NMDA Receptor Complex 总被引:4,自引:0,他引:4
Terence J. Coderre 《The European journal of neuroscience》1993,5(4):390-393
The present study was performed to examine the analgesic effects of the intrathecal administration of agents acting at various sites in the N -methyl- d -aspartic acid (NMDA) receptor complex on the nociceptive responses to s.c. formalin injection in rats. Both the competitive NMDA receptor antagonist 2-amino-5-phosphonovaleric acid (APV) and the non-competitive NMDA antagonist dizocilpine maleate (MK-801) produced dose-dependent analgesic effects in the late, but not the early, phase of the formalin test. The polyamine antagonist ifenprodil, and the strychnine-insensitive glycine antagonists DCQX and 7-chlorokynurenic acid, failed to produce any analgesic effects in either the early or the late phase of the formalin test. The analgesic effects of APV were enhanced slightly by combined administration with a non-analgesic dose of glycine, and the analgesic effects of MK-801 were dramatically potentiated by combined adminstration of a non-analgesic dose of the polyamine spermine. The results indicate that much more potent analgesia can be produced in the formalin test by a combination of open channel blockers (such as MK-801) with agonists acting at the polyamine site, than by a single treatment with antagonists to either glycine allosteric or polyamine sites within the NMDA receptor complex. 相似文献
9.
Early increases in transglutaminase activity and polyamine levels in a Mallory-Denk body mouse model
Rodents treated with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) are a model of two hepatic toxic manifestations: porphyria and the appearance of hepatic cytoplasmic protein aggregates (Mallory-Denk Bodies, MDBs). MDBs are induced after long-term DDC feeding, consist primarily of keratins 8 and 18, and contain glutamine-lysine cross-links generated by transglutaminases (TGs). TGs are Ca2+-dependent enzymes which catalyze the formation of covalent bonds between proteins and between proteins and polyamines. The aim of the current study was to investigate the time-course of TG hepatic activity in CF1 male mice either acutely or chronically treated with DDC and to correlate this activity with polyamine and porphyrin levels. On day 3 of the treatment, statistically significant increases in TG activity (75%), porphyrin content (6740%) and spermidine levels (73%) were observed. Although not statistically significant, at this time point putrescine levels showed an increase of 52%. The highest TG activity was observed on day 30 (522%), while porphyrin levels were still gradually increasing by day 45 (37,000%). From day 7 of the treatment and until the end of the experiment, putrescine levels remained increased (781%). Spermine levels were not affected by the treatment. The DDC-induced increases in putrescine and spermidine levels herein reported seem to be an early event contributing to the stimulation of liver TG activity, and thus to the promotion of cross-linking reactions between keratin proteins. This in turn would contribute to the formation of protein aggregates, which would lead to the appearance of MDBs. Due to the pro-oxidant and antioxidant properties of polyamines, it is possible to speculate that putrescine and spermidine may also participate at several levels in the oxidative stress processes associated with MDB formation. 相似文献
10.
Carl S. Killian Farida P. Vargas Gerald P. Murphy Somnulu Beckley T. Ming Chu 《Journal of clinical laboratory analysis》1987,1(4):332-338
A sensitive and reproducible method for quantitation of polyamines in erythrocytes by high-performance liquid chromatography (HPLC) is described. Spermidine and spermine are first converted to fluorescent dansyl derivatives and are then separated in less than 15 minutes on a C18 reverse-phase cartridge using methanol in water mobile phase. Sensitivity of the method is 20 pmol with recoveries that average 96% and 95% for spermidine and spermine, respectively. Precision study revealed an average mean coefficient of variation of 5.42 ± 2.95 (mean ± S.D.) from four levels of the polyamines (8.2 to 354.9 nmol/g hemoglobin [Hgb]). The normal ranges for 30 apparently healthy men and women, aged 20–60 years, were 2.9–33.7 nmol/g Hgb (± 2 S.D. from mean) for spermidine and 0-20.9 nmol/g Hgb for spermine. The quantity of putrescine was negligible. Feasibility of this method was evaluated in serial specimens from an advanced-stage patient with prostate cancer who was receiving multiple-modality therapy. Results revealed that this HPLC method can be used in quantifying circulating polyamines in clinical specimens. 相似文献