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141.
Currently, there is a paucity of data describing endometrial growth, with most studies concentrating on endometrial thickness immediately prior to implantation or embryo transfer. This study looked at the individual and combined growth profiles of 67 volunteers receiving three different hormone replacement regimens. Each treatment regimen was in excess of that considered necessary for optimal growth, and all promoted an endometrial thickness that would be considered satisfactory for embryo transfer. Three patterns of growth were identified, but overall there was a decrease in the rate of endometrial growth with duration of treatment. As expected, analysis of variance did not show a significant difference between the mean growth profiles for the three hormone replacement regimens. The correlation (r = 0.45, P < 0.0001) between rank order on day 3 and day 10 of treatment indicates that interim analysis during early treatment cannot accurately predict later thickness, but a doubling of endometrial thickness can be expected in most cases. A relationship between endometrial thickness and either the treatment dose or serum concentrations of oestradiol was not found. These findings suggest that manipulation of endometrial growth is not possible by adjustment of either the treatment dose or serum concentration. The findings indicate that treatment beyond 12 days does not promote either a clinically significant increase in endometrial thickness of an excessive thickness, suggesting that maintenance of an oocyte recipient in a pseudo-follicular phase is unlikely to be disadvantageous to implantation.  相似文献   
142.
Plasma concentrations of isepamicin, a new aminoglycoside antibiotic, were determined by radioimmunoassay (RIA), microbiological assay (MA), and high-performance liquid chromatography (HPLC) in healthy volunteers after administration of 7.5 mg/kg intramuscular dosages once daily for 10 days. Plasma samples were collected on days 1, 7, and 10. The limit of quantitation (LOQ) was 0.1 microg/ml for HPLC and RIA and 0.5 microg/ml for MA. The HPLC and RIA yielded superimposable plasma concentration-time curves, whereas the plasma concentrations obtained with MA appeared to be 20% to 30% lower. Regression analysis indicated good correlations among the three assays, with coefficients of correlation measuring 0.935 to 0.960 for RIA compared with HPLC, 0.925 to 0.945 for MA compared with HPLC, and 0.920 to 0.945 for RIA compared with MA.  相似文献   
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Although the discriminative properties of cocaine have been examined extensively in rats, and to a lesser extent in other species, there are currently no reports on cocaine discrimination by mice. In one of our experiments, C57BL/6 (C57) mice acquired cocaine discrimination (10 mg/kg training dose) and exhibited dose responsive generalization to lower doses of the drug, which was similar to previous reports using rats. In addition, mazindol, a general monoamine uptake inhibitor similar to cocaine, and nomifensine, which is relatively specific for the dopamine transporter, substituted completely for cocaine, as described for rats. In contrast, there was little substitution evidenced by monoamine uptake inhibitors relatively specific for the norepinephrine transporter (nisoxetine) or for the serotonin transporter (fluoxetine), or by the local anesthetics procaine or lidocaine. In our second experiment, neither cocaine nor mazindol substituted for procaine in animals trained to discriminate the local anesthetic (100 mg/kg) although lidocaine substituted completely for the procaine cue. These experiments emphasize the importance of the dopamine transporter in mediating the discriminative stimulus effects of cocaine in C57 mice. The lack of cross generalization between cocaine and procaine suggests that the anesthetic properties of cocaine contribute little toward its discrimination by this mouse strain.  相似文献   
144.
A single-chain Fv (sFv) was expressed from the variable regions of the CD40-specific mAb G28-5. The molecule bound CD40 with a high affinity (2.2 nM) and was a monomer in solution. Surprisingly, G28-5 sFv was a potent CD40 agonist that rapidly crosslinked CD40 on the cell surface but did not crosslink CD40-Ig in solution. G28-5 sFv was a more potent agonist than G28-5 IgG and was able to stimulate CD40 responses by B cells and monocytes. G28-5 IgG partially blocked, whereas G28-5 sFv augmented CD40 responses during stimulation with natural ligand (gp39-CD8 fusion protein). These results indicate that the functional activity of ligands built from the binding site of G28-5 is highly dependent upon the size and physical properties of the molecule both in solution and on the cell surfaces.  相似文献   
145.
Proteinuria in passive Heymann nephritis is primarily caused by reactive oxygen species that are produced by glomerular cells. Reactive oxygen species apparently exert their damaging effects on the glomerular filter by lipid peroxidation and subsequent adduct formation on matrix proteins of glomerular basement membranes. This raised the question as to the source of polyunsaturated fatty acids required as substrates for lipid peroxidation. Here we have localized by immunocytochemistry rat apolipoprotein E and apolipoprotein B within subepithelial immune deposits. Moreover, apolipoprotein B extracted from isolated glomeruli of proteinuric passive Heymann nephritis rats shows degradation and lipid peroxidation adduct formation, similar to apoproteins of oxidized lipoproteins in atherosclerotic lesions. These data provide evidence that lipoproteins accumulate within immune deposits and suggest that their lipids generate lipid-peroxidation-derived reactive compounds.  相似文献   
146.
OBJECTIVE: To evaluate the causes, clinical presentation, diagnosis, operative management, postoperative care, and outcome in infants with intestinal atresia. DESIGN: Retrospective case series. SETTING: Pediatric tertiary care teaching hospital. PATIENTS: A population-based sample of 277 neonates with intestinal atresia and stenosis treated from July 1, 1972, through April 30, 1997. The level of obstruction was duodenal in 138 infants, jejunoileal in 128, and colonic in 21. Of the 277 neonates, 10 had obstruction in more than 1 site. Duodenal atresia was associated with prematurity (46%), maternal polyhydramnios (33%), Down syndrome (24%), annular pancreas (33%), and malrotation (28%). Jejunoileal atresia was associated with intrauterine volvulus, (27%), gastroschisis (16%), and meconium ileus (11.7%). INTERVENTIONS: Patients with duodenal obstruction were treated by duodenoduodenostomy in 119 (86%), of 138 patients duodenotomy with web excision in 9 (7%), and duodenojejunostomy in 7 (5%) A duodenostomy tube was placed in 3 critically ill neonates. Patients with jejunoileal atresia were treated with resection in 97 (76%) of 128 patients (anastomosis, 45 [46%]; tapering enteroplasty, 23 [24%]; or temporary ostomy, 29 [30%]), ostomy alone in 25 (20%), web excision in 5 (4%), and the Bianchi procedure in 1 (0.8%). Patients with colon atresia were managed with initial ostomy and delayed anastomosis in 18 (86%) of 21 patients and resection with primary anastomosis in 3 (14%). Short-bowel syndrome was noted in 32 neonates. MAIN OUTCOME MEASURES: Morbidity and early and late mortality. RESULTS: Operative mortality for neonates with duodenal atresia was 4%, with jejunoileal atresia, 0.8%, and with colonic atresia, 0%. The long-term survival rate for children with duodenal atresia was 86%; with jejunoileal atresia, 84%; and with colon atresia, 100%. The Bianchi procedure (1 patient, 0.8%) and growth hormone, glutamine, and modified diet (4 patients, 1%) reduced total parenteral nutrition dependence. CONCLUSIONS: Cardiac anomalies (with duodenal atresia) and ultrashort-bowel syndrome (<40 cm) requiring long-term total parenteral nutrition, which can be complicated by liver disease (with jejunoileal atresia), are the major causes of morbidity and mortality in these patients. Use of growth factors to enhance adaptation and advances in small bowel transplantation may improve long-term outcomes.  相似文献   
147.
Cell-cell adhesion mediated by E-cadherin is often lost or disturbed in human carcinomas. For regular adhesive function, E-cadherin has to form complexes with peripheral cytoplasmic catenins which are multifunctional proteins that are also involved in signal transduction and growth regulation. We have analyzed the expression levels of the genes encoding alpha-catenin, beta-catenin and plakoglobin in correlation to the E-cadherin expression levels in cell lines derived from human cervical carcinomas. Reduced mRNA and protein levels were detected for plakoglobin, whereas alpha- and beta-catenin showed only reduced protein (but not mRNA) levels. The alterations in catenin gene expression were often associated with absent or reduced E-cadherin. The findings indicate that a reduction of catenin gene expression may contribute to the development of cervical carcinomas.  相似文献   
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We have isolated and sequenced a novel 11-kDa virucidal protein, named cyanovirin-N (CV-N), from cultures of the cyanobacterium (blue-green alga) Nostoc ellipsosporum. We also have produced CV-N recombinantly by expression of a corresponding DNA sequence in Escherichia coli. Low nanomolar concentrations of either natural or recombinant CV-N irreversibly inactivate diverse laboratory strains and primary isolates of human immunodeficiency virus (HIV) type 1 as well as strains of HIV type 2 and simian immunodeficiency virus. In addition, CV-N aborts cell-to-cell fusion and transmission of HIV-1 infection. Continuous, 2-day exposures of uninfected CEM-SS cells or peripheral blood lymphocytes to high concentrations (e.g., 9,000 nM) of CV-N were not lethal to these representative host cell types. The antiviral activity of CV-N is due, at least in part, to unique, high-affinity interactions of CV-N with the viral surface envelope glycoprotein gp120. The biological activity of CV-N is highly resistant to physicochemical denaturation, further enhancing its potential as an anti-HIV microbicide.  相似文献   
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