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991.
T Moriki  T Takahashi  M Wada  S Ueda  M Ichien  T Yamane  H Hara 《Canadian Metallurgical Quarterly》1997,193(9):629-39; discussion 640-2
Follicular dendritic cell (FDC) tumor is an exceedingly rare malignant neoplasm and occurs mainly in the cervical lymph nodes. We report a mesenteric FDC tumor occurring in a 66-year-old female, that manifested with intraabdominal multifocal recurrence 7 years after resection of the primary tumor. Histologically, both primary and recurrent tumors were composed of oval to spindle cells with paley eosinophilic cytoplasms, indistinct cell borders, round to elongated nuclei with clear or finely dispersed chromatin, and medium to large nucleoli. Characteristically, the tumor cells were growing in sheets, fascicles, and sometimes in whorls and a storiform pattern. In addition, focal necrosis, nuclear pleomorphism and abnormal mitoses were also observed. The neoplastic cells were intimately admixed with small lymphocytes. The diagnosis was confirmed by positive immunoreactivity with CD21 and CD35 antibodies and by ultrastructural demonstration of convoluted interdigitating cell processes connected by scattered desmosome-like junctions. Although our case showed a low proliferative activity evaluated by MIB-1, multifocal recurrence has occurred. The clinicopathologic features and differential diagnosis of FDC tumors are discussed with the review of the literature.  相似文献   
992.
Effects of a newly developed Ca2+ channel antagonist, (4R)-(-)-2-(nicotinoylamino)ethyl 3 nitrooxypropyl 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl) 3,5-pyridine-dicarboxylate (CD-832), on hypertensive complications in stroke-prone spontaneously hypertensive rats (SHRSPs) were compared with effects of diltiazem. We examined changes in histological and hematological parameters in SHRSPs given the following treatments at 8 to 20 weeks of age: (a) CD-832; (b) diltiazem; (c) no treatment. CD-832 and diltiazem were added to the diet, in doses of 0.05 and 0.15% (approximately 30 and 100 mg/kg per day), respectively, throughout the experimental period. In untreated control SHRSPs, systolic blood pressure increased and severe renal lesions such as fibrinoid necrosis, smooth muscle proliferation, glomerular and tubular lesions and some cardiac fibrosis were observed at age 20 weeks. 12-week repeated-administration of CD-832 and diltiazem led to a comparable hypotension and decreased heart rate. CD-832 and diltiazem decreased the ratios of weights of kidney and heart to body weight and the concentration of blood urea nitrogen and creatinine in serum, compared to values in controls. In SHRSPs treated with CD-832 and diltiazem, the incidence of renal lesions and myocardial fibrosis was significantly reduced when compared with control SHRSPs. These results suggest that 12-week repeated-administration of CD-832 prevents the development of hypertension and the incidence of organ damage in SHRSPs. CD-832 and diltiazem were equally efficacious in preventing organ damage but this organ-protective effect was obtained at a lower dose for CD-832 (30 mg/kg per day) than that of diltiazem (100 mg/kg per day).  相似文献   
993.
We previously established a limited sampling model (LSM) for the area under the concentration versus time curve (AUC) of irinotecan (CPT-11). Using this LSM, we performed a pharmacokinetic-pharmacodynamic analysis of CPT-11 in a multicentric Phase II study for non-small cell lung cancer. Ten institutes participated in this study, 36 patients were registered, and 30 patients were evaluable for the pharmacokinetic-pharmacodynamic analysis. CPT-11 and etoposide were administered daily for three consecutive days, both at a dose of 60 mg/m2. Blood samples were obtained 4 and 8 h after infusion on days 1 and 3. When using the LSM, there is a significant possible source of error in the timing of these selected points. In this study, however, the sample timing error was small. Mean timing errors were 1.0-4.0 min at each point. The estimated CPT-11 AUCs were: Day 1 Day 2 Day 1 + 3 Mean +/- SD (mg.h/liter) 3.76+/-0.68 4.10+/-0.86 7.86+/-1.43 Range 2.01-5.03 2. 29-5.72 4.30-10.68 Max/min 2.50 2.45 2.48 High interpatient variability was observed in the AUC. The CPT-11 AUC correlated positively with the grade of emesis (P = 0.003) and the percent decreases in WBC count (P = 0.001) and absolute neutrophil count (P =0.0006), but it did not correlate with the grade of diarrhea or response. We concluded that the LSM was useful in estimating individual pharmacokinetic parameters in multicentric trials.  相似文献   
994.
The aim of this study was to compare the accuracy and reliability of simple methods of quantifying regional cerebral blood flow (rCBF) with 123I-labeled N-isopropyl-p-iodoamphetamine (IMP) and SPECT and to determine which method was best. METHODS: Four methods were examined: (a) the microsphere method with continuous withdrawal of arterial blood, which was based on a microsphere model using the SPECT image obtained 5 min after tracer injection, (b) the microsphere method with one-point sampling, which was the same as the first method except that one-point sampling was used instead of continuous withdrawal, (c) the modified microsphere method with one-point sampling, which was the same as the second method except that a later SPECT image (30-min postinjection) with correction was used and (d) a table look-up method based on a two-compartment model with one-point arterial blood sampling and two SPECT scans obtained 40- and 180-min postinjection. The accuracy of these methods was validated by comparing the rCBF values with those obtained by nonlinear least squares fitting analysis based on the two-compartment model in 15 subjects. RESULTS: Regional cerebral blood flow values obtained by the first method correlated most closely with those obtained by nonlinear least squares fitting analysis (error, 6.8%). The second method estimated rCBF with a mean error of 10.4%. The third method estimated rCBF with a mean error of 13.1%, even though it tended to slightly overestimate rCBF. The fourth method was inclined to underestimate rCBF with a mean error of 17.1%, and it greatly overestimated regional distribution volume. CONCLUSION: The first method was the most accurate and reliable. For less invasiveness, the first method should be combined with one-point sampling instead of continuous withdrawal, which was used in the second method. When using a delayed SPECT image with a conventional SPECT scanner, the third method was considered to be superior to the fourth method.  相似文献   
995.
996.
BACKGROUND/AIMS: Despite the high frequency of early colorectal cancer, little is known about the clinicopathologic features of invasive early colorectal cancer for which endoscopic polypectomy is not indicated. We wanted to determine the clinicopathologic features of these early colorectal cancers. MATERIALS AND METHODS: From 1973 to 1994, a total of 728 patients with colorectal cancer were reviewed retrospectively from hospital records. The clinicopathologic features of the 90 invasive early colorectal cancer patients who underwent major surgeries were compared with those of 626 patients with advanced colorectal cancer. RESULTS: The frequency of early colorectal cancer increased significantly from the periods 1973-1979 to 1990-1994: 0% in the former period and 18.3% in the later period. Minimally invasive surgery was chosen more frequently for the treatment of early colorectal cancers than for the treatment of advanced cancers (p < 0.005). Lymph node metastasis, lymph vessel invasion, and vascular invasion were more prevalent in advanced cancer cases than in early cancer cases (p < 0.005). Lymph node metastasis was found in 7 patients with early colorectal cancer (7.8%). There was no difference in histologic type between the early and advanced colorectal cancers. The 5-year survival rates of early colorectal cancer patients were higher than those of advanced cancer patients: 97.5% in early colon cancer patients; 93.5% in early rectal cancer patients; 59.8% in advanced colon cancer patients; 55.4% in advanced rectal cancer patients. Three early colorectal cancer patients died of recurrence. CONCLUSION: Minimally invasive surgery such as laparoscopic colectomy should be performed on patients with invasive early colorectal cancer when it is impossible for the cancer to be removed by endoscopic polypectomy.  相似文献   
997.
The use of biomarkers is a promising approach to the study of human cancer risk. Bronchial metaplasia in sputum cytology may be a marker for potential premalignancy that can be used for population studies. We recently performed a randomized, controlled trial in smokers on the effect of 14 weeks beta-carotene (20mg/day) on markers for DNA damage. We now have evaluated the application of sputum cytology in this study and performed a preliminary evaluation of the effect of beta-carotene. Of the 150 potential participants in this trial 75 were not eligible because they failed to produce sputum samples (n = 29), or because samples were unsatisfactory (n = 46). The eligible group was older (41 vs 37 years) and had smoked longer (23 vs 19 years), but had similar cigarette consumption (mean 21/day) and plasma cotinine levels. Metaplasia was graded in seven categories. Only 11 subjects (15%) showed minor or mild atypia on study entry. Agreement within and between observers was 95% within the same or an adjacent category. We observed no significant correlation between before and after treatment final metaplasia scores in either the beta-carotene (Spearman R = 0.18, P = 0.3) or placebo group (Spearman R = 0.17, P = 0.3). Initial metaplasia scores were somewhat higher in the beta-carotene group (n = 33) than in the placebo group (n = 42) (P = 0.06). Final metaplasia scores were similar in both groups (P = 0.69), and there was no decrease in metaplasia scores in the beta-carotene group (P = 0.75). This study indicates that sputum cytology may not yet be a readily applicable marker in studies of a healthy asymptomatic population, because many smokers do not spontaneously produce sputum, more severe lesions are rare, and variation over time in the minor lesions in large. Therefore, the preliminary evidence that beta-carotene has no influence should be interpreted with care.  相似文献   
998.
We studied chest X rays of 911 patients with rheumatoid arthritis (RA). The findings showed interstitial shadow in 28 patients (3.1%), pleuritis in 13 patients (1.4%) and nodular shadow in 3 patients (0.3%). RA patients with interstitial pneumonia were commonly male and older. And they had significantly high levels of rheumatoid factor (RF), RAPA and IgG-RF in serum, but they were not associated with high score of Lansbary index. All patients with more than 1500 IU/ml in RF value had a complication of interstitial pneumonia. These results suggest the importance of chest X-ray in the management of RA patients with high titer in RF.  相似文献   
999.
A 3-year child presented with episodic lower abdominal pain; during the eighth attack, a mass was palpable in the left upper quadrant, and a barium enema revealed a stenotic area in the transverse colon. This was resected and an uneventful postoperative course followed. Subsequently, the child has remained symptom-free. instruments are no longer in use.  相似文献   
1000.
This study investigated the features of calf deep vein thrombosis (DVT) as a pulmonary embolic source. Fifty-eight lower limbs in 29 patients who were suspected of having DVT distal to the popliteal vein were screened by ultrasonography. Then, ascending venography was performed to confirm the diagnosis. Pulmonary embolism (PE) was diagnosed in suspected patients by use of pulmonary perfusion scanning or pulmonary angiography. Venography revealed calf DVT in 33 limbs in 28 patients. Of 28 patients, six had symptomatic PE. Thrombosis was found in the muscle veins in 18 limbs, the trunk veins in 11, and both veins in four. Isolated single vein thrombosis was found in the soleal vein in 14 limbs (42%), the posterior tibial vein in eight, the peroneal vein in two, and the gastrocnemius vein in two. The overall percentage of soleal vein thrombi was 61%. All six patients with symptomatic PE had isolated soleal vein thromboses. Calf DVT was a pulmonary embolic source when isolated thrombosis of the large soleal vein was more than 7 mm in diameter. Soleal veins were the most frequent and important location of calf DVT, suggesting that these were an occasional embolic source of critical PE.  相似文献   
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