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951.
PURPOSE: Functional alterations of the gastrointestinal and genitourinary tracts, and physical limitations in children with spina bifida, imperforate anus and spinal cord injury challenge the ability to have independent fecal and urinary continence. Urologists have successfully helped these patients achieve urinary continence. We report our experience with the antegrade colonic enema procedure, which allows select individuals to achieve continence of stool, enhancing quality of life. MATERIALS AND METHODS: Since December 1992, 18 antegrade colonic enema procedures were performed in 12 female and 6 male patients 5 to 31 years old of whom 14 had spina bifida, 2 had imperforate anus and 2 had spinal cord injury. Simultaneous urological continence procedures were performed in 8 patients, including appendicovesicostomy in 4, augmentation cystoplasty in 2 and augmentation cystoplasty plus an ileal Mitrofanoff procedure in 2. Four patients previously underwent urological reconstruction. RESULTS: In 24 months of followup (average 6.6) all patients with a functioning stoma remained continent of stool and 17 were continent of urine. Complications related to the antegrade colonic enema procedure occurred in 4 children (22%) of whom 3 required further surgery. Three patients (17%) had minor stomal stenosis. CONCLUSIONS: The antegrade colonic enema procedure is easily performed and it should be considered for any child with significant physical limitations and/or refractory fecal incontinence before urological continence promoting procedures are done.  相似文献   
952.
Lymphotoxin (LT) provides a critical signal for the genesis of lymph nodes (LN) in mice. Here we show that mice treated in utero with LT beta-R-Ig, which binds to the membrane LT alpha 1 beta 2 heterotrimer, lacked most LN, yet retained a set of mucosal surface draining LN. Since mice genetically deficient in LT alpha lack all LN, including the mucosal set, we hypothesize that a novel LT alpha-dependent pathway controls their genesis. This novel set of mucosal LN cannot be discriminated on the basis of addressin expression. The discovery of LN in mice treated with LT beta-R-Ig fusion protein in utero allowed us to compare the roles of membrane LT alpha beta or soluble LT alpha/tumor necrosis factor (TNF) in the development of cellular organization in LN and spleen. Our results indicate that both membrane LT alpha beta and soluble LT alpha/TNF mediate T-B cell segregation and the organization of B cell follicles in spleen and LN. Interestingly, while antagonism of membrane LT alpha beta or soluble LT alpha/TNF prevented germinal center (GC) formation in spleen, antagonism of soluble LT alpha/TNF had no effect on LN formation. The data suggest that multiple LT/TNF ligands control B cell follicle organization in the spleen and LN of adult mice, and that the requirements for LT/TNF ligands in GC formation are distinct in the different lymphoid organs.  相似文献   
953.
During the past two decades, the initial treatment of an advanced ovarian malignancy has been generally uniform: it begins with an exploratory laparotomy surgically to remove as much tumor as possible (1) and to stage the cancer (2). For the 70% of patients classified as stages III and IV, surgery is then followed by combination chemotherapy. Although opinions differ as to the optimal regimen, the standard involves a platinum-based program (3), recently also including paclitaxel (4). A second-look laparotomy is often performed in all patients who achieve a clinical complete remission, that is the inability to detect disease by physical examination and non-invasive laboratory tests. This surgical procedure is able to detect clinical disease not apparent on computerized axial tomography (CT scan), ultrasound, magnetic resonance imaging (MRI), serum CA-125 levels or physical examination (5-7). Major questions, however, have arisen around the need for such a procedure, and whether one can justify it in terms of an improved outcome or merely as an assessment of prognosis (8-14). We shall review: (i) the technique; (ii) the rationale; (iii) the results that have been reported from its routine application; and (iv) controversial issues, particularly as they relate to the evolution of therapeutic strategies.  相似文献   
954.
Quantitative microculture assays of cryopreserved human immunodeficiency virus type 1-infected cell suspensions and culture supernatants were compared among seven assays sites. There was no significant change in titer during 1 year of storage. The overall standard deviation for infected cell suspensions was approximately 0.8 log10 virus titer. A method for detecting deviant assay results was developed and was used to identify two donor cell preparations (n = 54) that gave consistently low titers.  相似文献   
955.
956.
Swine infectious agents, especially viruses, are potential public health risks associated with the use of pig organs for xenotransplantation in humans. Therefore, there is a need for better characterization of swine viruses and for the development of diagnostic tests for their detection. We report here isolation of a novel strain of porcine circovirus (PCV) from pigs with postweaning multisystemic wasting syndrome (PMWS). Affected pigs exhibited severe interstitial pneumonia and lymphoid depletion. The complete nucleotide sequence (1,768 nucleotides) of the genome of the PCV isolate was determined and compared with the sequence of the PCV strain isolated from PK-15 cells. Sequence comparison revealed significant differences between the two PCV strains, with an overall DNA homology of 76%. Two major open reading frames (ORFs) were identified. ORF1 was more conserved between the two strains, with 83% nucleotide homology and 86% amino acid homology. ORF2 was more variable, with nucleotide homology of 67% and amino acid homology of 65%. PCR and in situ hybridization demonstrated abundant viral DNA in various organs of pigs with PMWS. In situ hybridization demonstrated that this strain of PCV targets multiple organs and infects macrophages, lymphocytes, endothelial cells, and epithelial cells.  相似文献   
957.
The technique involving filtration of diluted blood enables the separate analysis of the flow properties of different cell subpopulations. This study was designed to assess the changes occurring in the flow properties and function of blood cells in stored bank blood and salvaged blood compared to patient blood in a given clinical situation. We measured hydrogen peroxide production by neutrophils and the filterability, through 5 microm Nucleopore filters, of isolated red blood cells and of diluted blood. Samples were obtained from patients undergoing aortic surgery and blood intended for transfusion: either salvaged during surgery or stored bank blood. Both salvaged and bank blood were much less filterable than patient blood, with reduced deformability of both red and white blood cells. However, salvaged blood contained highly activated neutrophils with a prolonged transit time of the 'fast-flowing' cells in the analysis compared to bank blood. Bank blood contained significantly more particles which acted as pore-blockers. Cells in bank and salvaged blood therefore have markedly abnormal flow and biochemical properties compared to patient blood.  相似文献   
958.
In the current study, we investigated whether the naive, poly I:C or interleukin-2 (IL-2)-induced natural killer (NK)/lymphokine-activated killer (LAK) cells use perforin and/or Fas ligand (FasL) to mediated cytotoxicity. We correlated these findings with the ability of mice to reject syngeneic Fas+ and Fas- tumor cells either spontaneously or after IL-2 treatment. The spontaneous NK-cell-mediated cytotoxicity was primarily perforin based, whereas the poly I:C and IL-2-induced NK/LAK activity was both FasL and perforin dependent. L1210 Fas+ tumor targets were more sensitive than L1210 Fas- targets to poly I:C and IL-2-induced cytotoxicity in wild-type, gld/gld, and perforin knockout mice. When L1210 Fas+ and Fas- tumor cells were injected subcutaneously (sc) or intraperitoneally into syngeneic mice, Fas- tumor cells caused mortality earlier than Fas+ tumor cells. Also, approximately 20% of the mice injected sc with L1210 Fas+ tumor cells survived the challenge(>60 days), whereas all mice injected similarly with L1210 Fas- tumor cells died. When immunotherapy using IL-2 (10,000 U, three times/d for a week, followed by once/d for an additional week) was attempted in mice injected sc with tumor cells, IL-2 treatment was very effective against mice bearing L1210 Fas+ (40% survival) but not L1210 Fas- (0% survival) tumors. These data correlated with the finding that the LAK cells from IL-2-injected mice caused increased cytotoxicity against L1210 Fas+ when compared with L1210 Fas- targets. Also, L1210 Fas+ tumor-bearing mice showed increased tumor-specific cytotoxic T lymphocyte (CTL) activity when compared with those bearing L1210 Fas- tumor cells. Together our studies show for the first time that expression of Fas on tumor targets makes them more immunogenic as well as susceptible to CTL- and IL-2-induced LAK activity. The Fas+ tumor cells are also more responsive to immunotherapy with IL-2.  相似文献   
959.
von Willebrand factor (vWf) deficiency causes severe von Willebrand disease in humans. We generated a mouse model for this disease by using gene targeting. vWf-deficient mice appeared normal at birth; they were viable and fertile. Neither vWf nor vWf propolypeptide (von Willebrand antigen II) were detectable in plasma, platelets, or endothelial cells of the homozygous mutant mice. The mutant mice exhibited defects in hemostasis with a highly prolonged bleeding time and spontaneous bleeding events in approximately 10% of neonates. As in the human disease, the factor VIII level in these mice was reduced strongly as a result of the lack of protection provided by vWf. Defective thrombosis in mutant mice was also evident in an in vivo model of vascular injury. In this model, the exteriorized mesentery was superfused with ferric chloride and the accumulation of fluorescently labeled platelets was observed by intravital microscopy. We conclude that these mice very closely mimic severe human von Willebrand disease and will be very useful for investigating the role of vWf in normal physiology and in disease models.  相似文献   
960.
Transjugular intrahepatic portosystemic shunt (TIPS) is a procedure recently introduced for the management of complications of portal hypertension. TIPS can be placed in the liver with relative ease by a skilled radiologist with a low risk of mortality. The major complications following the procedure are infection, especially in patients undergoing emergency TIPS, intra-abdominal haemorrhage from capsular punctures, and long-term problems related to encephalopathy and stenosis of the shunt. Encephalopathy is more of a problem in older patients with wide diameter shunts. Stenosis of the shunt is related to pseudo-intimal hyperplasia, probably related to transection of bile ductules during placement of the shunt. In view of the high rate of encephalopathy and stenosis following the shunt, a careful follow-up of all patients, including ultrasonographic and angiographic examination of the shunt, is mandatory. TIPS is used predominantly for the control of acute variceal haemorrhage, prevention of recurrent variceal bleeding, and refractory ascites when conventional treatment has failed. However, the role of TIPS in the management of complications of portal hypertension still awaits the outcome of clinical trials.  相似文献   
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