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91.
The uterus of six healthy multiparous women at term was mechanically stretched by a rubber catheter and balloon. Apparent labor was inaugurated in all cases within 5 hours and increased progressively with time. Advanced cervical softening and dilatation were also evident after the stretch treatment. Significant increases in the levels of 13,14-dihydro-15-keto-prostaglandin F (PGFM) were observed with the progress of treatment (P < 0.01). Plasma estrogens and progesterone levels did not change significantly during the treatment (P > 0.05). Stretching and/or resulting uterine contractions appear to induce the secretion of prostaglandin F (PGF) from the organ, which in turn seems to be involved in both cervical softening, and the onset and progress of labor, under stable conditions of plasma estrogens and progesterone.  相似文献   
92.
A case of a 19-year-old, non-obese female with insulin resistant diabetes mellitus and polycystic ovary syndrome was reported. The maximal insulin requirement attained 360 units per day, but a satisfactory control of diabetes did not follow. The patient's serum contained not only anti-insulin antibodies, but also possible anti-insulin receptor antibodies which were demonstrated by the 125I-insulin binding test using insulin receptors derived from human placental plasma membrane. The insulin resistance in this case was assumed to be caused primarily by possible blocking antibodies to insulin receptors and partly by anti-insulin antibodies because of the following observations. First, high serum free insulin (165 microunits/ml) without hypoglycemia indicates the presence of insulin resistance due to other factors than antiinsulin antibodies. Second, the titer of 125I-insulin binding capacity of serum was not unusually higher than those seen in chronically insulin-treated diabetics. Third, immunologically heterospecies insulin (fish insulin) was also ineffective. The clinical features such as absence of ketoacidosis and association with polycystic ovary syndrome resemble those of an unique diabetic syndrome reported previously though acanthosis nigricans and endogenous hyperinsulinemia were not found in this case. Her insulin resistance remitted spontaneously and over the next 18 months' observation, her diabetes remained regulated without insulin therapy.  相似文献   
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CCR6 has been implicated in both autoimmune diseases and non-autoimmune diseases. Thus, inhibition of CCR6-dependent cell migration is an attractive strategy for their treatment. An orally available small molecule inhibitor of CCR6 could therefore be a useful biological probe for the pathophysiological studies. Initial SAR study of a hit compound provided potent N-benzenesulfonylpiperidine derivatives that suppressed CCL20-induced Gi signals. By subsequent scaffold morphing of the central ring and further optimization, we identified a novel series of 1,4-trans-1-benzenesulfonyl-4-aminocyclohexanes as potent and selective CCR6 inhibitors with good pharmacokinetic properties. Our compounds showed good correlation between Gi signal inhibitory activity and cell migration inhibitory activity in human CCR6-transfected CHO cells. In addition, representative compound 35 potently inhibited CCR6-dependent cell migration and the increase in ERK phosphorylation in human primary cells. Therefore, the compound could be used effectively as a biological probe against human CCR6.  相似文献   
95.
Donor–acceptor (D‐A) type π‐conjugated copolymers with crystalline behavior have been extensively investigated as donor semiconductors in organic photovoltaics (OPVs). On the other hand, the development of high‐performance amorphous donor materials is still behind. The amorphous donor copolymer DTS‐C0(F2) consisting of dithieno[3,2‐b:2′,3′‐d]silole ( DTS ) donor unit and the recently developed fluorine‐substituted naphtho[2,3‐c]thiophene‐4,9‐dione ( C0(F2) ) acceptor unit shows moderate photovoltaic performance upon blending with PC71BM. In this work, to enhance the hole‐transporting characteristics, a 3‐hexylthiophene ( HT ) spacer unit is integrated into the conjugated backbone, resulting in a new amorphous copolymer DTS‐HT‐C0(F2) . The strong electron‐accepting nature of C0(F2) allows the introduction of the HT spacer without affecting the frontier orbital energies and thus the D‐A character. Without using solvent additives and thermal annealing, OPVs based on DTS‐HT‐C0(F2) and [6,6]‐phenyl‐C71‐butyric acid methyl ester PC71BM show an improved power conversion efficiency of 9.12%. Investigation of the device physics unambiguously reveals that the hole mobility of the copolymer in the blend is increased by an order of magnitude by the introduction of HT , while keeping an amorphous film nature, leading to higher short‐circuit current density and fill factor. These results demonstrate the realization of high‐performance OPVs based on amorphous active layers.  相似文献   
96.
Castrillo  M.  Aso  P.  Longart  M.  Vermehren  A. 《Photosynthetica》1997,33(1):39-50
The location of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) in the leaf mesophyll of some dicotyledonous C4 plants was confirmed by immunofluorescent labelling. The anti-RuBPCO immune serum was obtained by inoculating a rabbit with commercially obtained RuBPCO. Specificity of these antibodies was tested by immunodiffusion, immunoelectrophoresis, and Western blotting. Fresh hand-cuts of leaves from dicotyledonous C4 plants, Amaranthus caudatus, A. dubius, Gomphrena globosa, and Portulaca oleracea, were incubated with the conjugated anti-RuBPCO immune serum and then with a commercial FITC-anti-rabbit IgG conjugate. Nerium oleander was used a control C3 plant pattern and Zea mays as a C4 plant pattern. The immunofluorescent label was distributed in both mesophyll and bundle sheath in all the C4 plants tested. It is an unequivocal proof that in the C4 dicotyledonous plants the RuBPCO is not only located in the chloroplasts of the bundle sheath cells but also in the chloroplasts of the mesophyll cells. In these plants therefore, the C4 pathway cannot exclusively be viewed as an intercellular level concentration mechanism. In the mesophyll cytoplasm, phosphoenolpyruvate carboxylase traps CO2, while in the mesophyll chloroplasts, RuBPCO operates with atmospheric CO2 and CO2 from the C4 decarboxylation step at an intracellular level, which could mean a significant energetic economy. The CO2 from photorespiration could be saved and reincorporated. Location of RuBPCO in the mesophyll and/or bundle sheath chloroplasts is a matter of inter- and intracellular compartmentation which makes another variation of C4 photosynthetic pathway possible. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
97.
98.
A line of S-(2-aminoethyl)-L-cysteine-resistant adenine-auxotrophiccells (AdAECr strain) was isolated from adenine-auxotrophiccells (Ad strain) of Datura innoxia Mill by a stepwiseselection method. AdAECr and Bl cells, which were clonedfrom the original AdAECr cells, were able to grow activelyon medium that contained 10 mM S-(2-aminoethyl)-L-cysteine (AEC),whereas the growth of Ad cells ceased completely in thepresence of 0.5 mM AEC. The resistant phenotype has been maintainedfor at least 10 months in culture on medium without AEC. Levels of free lysine in AdAECr and Bl cells were similarto that in Ad cells. By contrast, the level of free AECin AdAEC cells was 10-fold lower than in Ad cellsand no free AEC was detectable in Bl cells. However, acid hydrolysisof extracts from AdAECr and Bl cells resulted in a remarkableincrease in levels of detectable AEC. This result indicatesthat conjugated AEC is synthesized and accumulated in the AEC-resistantcells. The level of the AEC conjugate in Bl cells increasedwith increases in the concentration of AEC in the culture medium,while intracellular levels of AEC were so low as not to be detectablein the case of cells grown on medium supplemented with AEC atless than 1 mM. The AEC conjugate was also detected in Adcells, but at lower levels than in the AEC-resistant cells.In addition, AEC was found to be incorporated into soluble proteinsin Ad cells. These results suggest that the resistance of AEC-resistant cellsof Datura innoxia is accomplished via acceleration of the synthesisof the AEC conjugate which prevents any increase in intracellularlevels of free AEC. 1Present address: Institute for Biology and Chemistry, TsumuraCo.Ltd., Inashiki, Ibaraki, 300-03 Japan. 2Present address: North Kanto Shop, Sakata Seed Co. Ltd.,Saitama,347 Japan.  相似文献   
99.
Some of luteinizing hormone (LH) isoforms can stimulate renal growth. The objective of this study is to determine whether the administration of LH modifies subtotal nephrectomy-induced chronic renal failure. Castrated 3/4-nephrectomized male rats were divided into four groups of seven each and fed a low-protein (6%) diet. Ovine LH with renotropic activity (40 micrograms/day) or vehicle only (control) was given for three weeks or six weeks. Compared with controls, remnant kidney weights (% body weight) in LH-treated rats had increased significantly at three weeks (0.385 +/- 0.019 vs 0.443 +/- 0.052, P less than 0.02), but not at six weeks (0.281 +/- 0.004 vs 0.272 +/- 0.013). 24 h creatinine clearance (ml/day/100 g body weight) increased significantly both by three weeks (242 +/- 58 vs 301 +/- 36, P less than 0.05), and six weeks (323 +/- 55 vs 395 +/- 10, P less than 0.01). Urinary thromboxane B2 excretion increased in LH-treated rats, suggesting that hemodynamic changes may play a role in increasing creatinine clearance. Our results suggest that renotropically active oLH stimulated the glomerular function in castrated rats with reduced renal mass. Further study may clarify its clinical usefulness.  相似文献   
100.
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