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11.
On the basis of a cost analysis of conservative and surgical therapy of gastroesophageal reflux disease in 70 patients health economic aspects are discussed. In a prospective documented series of reflux patients a retrolective analysis of medication cost and duration of conservative therapy is performed. In addition, the costs for surgical therapy including preoperative diagnostic workup, cost during hospitalization as well as costs for complications with necessary additional treatment and readmissions are assessed. For the conservative treatment of 70 reflux patients a total of more than DM < 700,000 had to be spent during preoperative 5 years. A major part of this sum was spent for patients who needed to increase the initial 20 mg dosage of Omeprazol within 5 years. A mean of approximately DM 2,000 per patient was spent for conservative treatment. Surgical treatment without complications was calculated with DM 5,425 per case. However, in 7 patients complications occurred causing prolonged or even rehospitalization with necessary further treatment summing up to about DM 486,000 for surgical therapy in 70 patients including complications. Cost relevant factors are therefore in conservative treatment patients who need increasing dosages, while, in surgical treatment, the cost relevant patients are those with complications and necessary additional treatment.  相似文献   
12.
PURPOSE: The differential diagnosis of early gastric mucosa-associated lymphatic tissue (MALT) lymphoma based on Helicobacter pylori gastritis may be difficult when lymphoepithelial lesions are not detected. The aim of the present study was to investigate the question whether the polymerase chain reaction (PCR) or cure of H pylori infection may be of help in this respect. PATIENTS AND METHODS: Twenty patients with suspected low-grade gastric MALT lymphomas were treated in a double-blinded, randomized, crossover trial with 2,250 mg of either amoxicillin or placebo, both in combination with omeprazole, for 14 days with the aim to cure H pylori infection. PCR was performed using primers specific for the CDR3 region to detect monoclonal B cells. RESULTS: In five of 20 patients, MALT lymphomas were finally diagnosed. Three of these five patients went into complete remission, while two were referred to surgery. In the 15 patients with gastritis, complete regression was observed in all cases. With respect to PCR, monoclonal bands were detected in all four of the analyzed lymphoma patients before histology showed lymphoma. In addition, monoclonal bands were found in three patients with gastritis. In the patients with gastritis and monoclonal PCR, complete regression took longer as compared with the remaining 12 patients with polyclonal PCR and gastritis (P = .0209). Successful H pylori eradication was associated with earlier diagnosis of the MALT lymphoma (P = .0237). CONCLUSION: CDR3-PCR may be of help in the differential diagnosis of early gastric MALT lymphoma. Furthermore, H pylori eradication may lead to earlier diagnosis.  相似文献   
13.
BACKGROUND: Cancer of the cardia is now topographically classified into three types: type I, with the tumor center in the distal esophagus treated with subtotal esophagectomy; type II, arising at the gastroesophageal junction and treated with distal esophagectomy and either proximal or total gastrectomy; and type III, subcardial cancer treated with extended total gastrectomy. Our objective was to review the new classifications and compare the outcomes in patients grouped and treated according to these classifications. METHODS: Seventy-four patients with cancer of the cardia--15 with type I, 30 with type II, and 29 with type III cancer--underwent surgical resection at our institution between 1992 and 1997. Postoperative complications, UICC stages, and survival (Kaplan-Meier) were compared. RESULTS: The majority of patients with type I (73%) or type II (53%) cancer had stage I or II tumors, but only 27% of patients with type III cancer had this tumor stage (P < .05). Overall 30-day mortality was 4% and morbidity was 31%. Curative resections were performed in 73% (54 of 74) of the patients with 3-year survival rates of 72% (type I), 68% (type II), and 61% (type III). CONCLUSION: The recommended therapy for the different types of cancer of the cardia results in acceptable morbidity, mortality, and survival rates.  相似文献   
14.
An IC technique for clock recovery and frequency multiplication was developed by combining a preprocessor, an injection-synchronised narrowband ring voltage controlled oscillator, and a phaselocked loop. A 40 Gbit/s/GHz IC was realised using 0.2 μm GaAs HEMTs. A multiplying factor as high as 64 was reached. The DC consumption is 900 mW  相似文献   
15.
An efficient method to lower the optical detection limit is described using the displacement of an absorption and emission band of an analyte after a polarity change in different solvents. This solvatochromic effect was used in a RP-HPLC assay for the fluorescence detection of mycophenolic acid (6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-5-phthalanyl)-4-methyl-4-hexenoic acid, MPA) and the prodrug mycophenolate mofetil (MMF), the N-(2-hydroxyethyl)morpholino ester of MPA. The rational to use fluorescence detection is based on the behavior of MMF and MPA, which fluoresce in a basic medium (pH >9.5). Following a simple protein precipitation, the analytes were separated in an isocratic RP-HPLC system. The postcolumn generation of the phenolate anions of MPA and MMF was achieved by addition of an aqueous sodium hydroxide solution regulated by a newly developed continuous-flow liquid control system. MPAG, not directly accessible for fluorescence detection, was analyzed after enzymatic deglucuronidation to MPA. Compared to published quantification limits for MPA and MMF by UV detection, this method is more than 100-fold more sensitive, with a lower limit of quantification of 45 fmol for both MPA and MMF.  相似文献   
16.
Recently, we introduced a novel approach for protein quantification based on isobaric peptide termini labeling (IPTL). In IPTL, both peptide termini are dervatized in two separate chemical reactions with complementary isotopically labeled reagents to generate isobaric peptide pairs. Here, we describe a novel procedure for the two chemical reactions to enable a cost-effective and rapid method. We established a selective N-terminal peptide modification reaction using succinic anhydride. Dimethylation was used as second chemical reaction to derivatize lysine residues. Both reactions can be performed within 15 min in one pot, and micropurification of the peptides between the two reactions was not necessary. For data analysis, we developed the force-find algorithm in IsobariQ which searches for corresponding peaks to build up peak pairs in tandem mass spectrometry (MS/MS) spectra where Mascot could not identify opposite sequences. Utilizing force-find, the number of quantified proteins was improved by more than 50% in comparison to the standard data analysis in IsobariQ. This was applied to compare the proteome of HeLa cells incubated with S-trityl-L-cysteine (STLC) to induce mitotic arrest and apoptosis. More than 50 proteins were found to be quantitatively changed, and most of them were previously reported in other proteome analyses of apoptotic cells. Furthermore, we showed that the two complementary isotopic labels coelute during liquid chromatography (LC) separation and that the linearity of relative IPTL quantification is not affected by a complex protein background. Combining the optimized reactions for IPTL with the open source data analysis software IsobariQ including force-find, we present a straightforward and rapid approach for quantitative proteomics.  相似文献   
17.
The design and performance of a dynamic frequency divider was presented. This digital IC demonstrates the ability of the authors' AlGaAs/GaAs/AlGaAs quantum-well FETs with gate lengths of 0.2 μm. Stable operation was achieved in the frequency range from 18 GHz up to 34 GHz with a power consumption of 250 mW. To the authors' knowledge, this is the best result ever reported for HEMT circuits, and is similar to the frequency limit achieved by use of AlGaAs/GaAs HBTs  相似文献   
18.
Modelling and analysing lifecycle environmental impacts of product systems demands often specialized knowledge and is time-demanding. Product systems are typically defined by complex technical foreground systems and immersed in highly diverse contexts and background systems. Available software tools fail to streamline the modelling and analysis of this complexity, leading to extensive iterations or rough simplifications. The approach introduced in this paper supports the modelling of complex systems and their interactions with diverse backgrounds. This enables developing flexible and comprehensive environmental assessment tools. The applicability and advantages of the approach developed is demonstrated through its application for the environmental assessment of electric vehicles.  相似文献   
19.
In twenty-five patients with a clinical diagnosis of suspected sacroiliitis conventional radiography, CT and MRI were performed. In ten patients no abnormalities were demonstrated. In thirteen cases CT and MRI revealed sacroiliitis. In two patients with normal plain films and CT para- and intraarticular changes of signal intensity suggested suspicious sacroiliitis. MRI can be considered as an important imaging modality for early diagnosis of sacroiliitis. In eighteen patients with a firm diagnosis of ankylosing spondylitis and plain films of the thoracolumbar junction suggesting destructive Romanus and Anderson inflammatory lesions MRI was done. Two distinct groups of inflammatory changes were found. In ten patients MRI findings compatible with active inflammatory enthesitis were revealed at the disco-vertebral junction. In eight cases focal and linear changes of signal intensity within the intervertebral disks suggested an active inflammation. Using MRI the spectrum of inflammatory changes in sero-negative spondylitis can be presented. In sixteen patients with definite clinical diagnosis (psoriatic arthritis--thirteen cases and Reiter's syndrome--three cases) plain films and MRI of small hand joints were performed. The patients fell into two distinct groups. In the first MRI findings could not be differentiated from those seen in rheumatoid arthritis. In nine cases the distribution and extent of soft tissue findings were different, similar to changes seen in enthesitis. Therefore, on the basis of MRI findings in small peripheral joints easier differential diagnosis between sero-negative spondyloarthritides and rheumatoid arthritis is possible. In five patients with a diagnosis of Reiter's syndrome having clinical signs of enthesitis plain films and MRI of calcaneus were done. MRI revealed findings compatible with active inflammation which resembled those seen at the attachment of the annulus fibrosus and collateral ligaments of the small hand joints.  相似文献   
20.
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