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431.
Uterine morphology assessed by transvaginal ultrasound and the hemodynamics of intratumoral vessels assessed by color Doppler ultrasound were prospectively correlated with the clinical outcome of 25 patients with trophoblastic tumors. Twenty patients were followed without treatment (observation group) and 16 achieved complete local resolution. The four subjects with local persistence were combined with five patients referred from other institutions and received chemotherapy (treatment group). In the observation group both techniques had 100% accuracy in predicting local resolution or local persistence. Persistence was predicted 1-3 weeks before the increase of beta-human chorionic gonadotropin (beta-hCG) levels, whereas resolution was observed up to 8 weeks before the disappearance of beta-hCG. In one patient normal uterine morphology and vascularization in the presence of elevated hCG levels was associated with extrauterine spread. In the treatment group, normal uterine ultrasound morphology and negative color Doppler results had 100% negative predictive value. False-positive results were observed in two cases. We conclude that ultrasound evidence of abnormal uterine morphology or persistent vascularization on color Doppler examination with persistent hCG levels is indicative of local persistence. Normal uterine morphology with negative color Doppler results may be associated with extrauterine spread.  相似文献   
432.
CD10 (CALLA) antigen is expressed in a wide variety of epithelial and nonepithelial tissues, but its most significant application is in the diagnosis and classification of certain types of malignant lymphoma and leukemia. CD10 is expressed in a high percentage of cases of acute lymphoblastic leukemia (ALL), follicular lymphoma, Burkitt's lymphoma, and some hematopoietic tumors. Although the antigen is not lineage specific, CD10 expression is widely used to define subgroups within B-ALL and is a useful tool for detecting the presence of leukemic blasts in the bloodstream. Currently available monoclonal antibodies to CD10 have been found to be effective only in fresh-frozen tissue and for techniques such as flow cytometry. We have used a recombinant protein corresponding to the whole of CD10 to generate a monoclonal antibody that is effective in paraffin-embedded tissue sections. We have used this antibody to assay for the presence of CD10 on a range of normal and pathological tissues. Strong staining was seen in lymphoid germinal centers, renal tubules, glomeruli, syncytiotrophoblast, hepatic parenchymal canaliculi, B-lineage ALL, follicle center cell lymphoma, and a proportion of cases of large-B-cell lymphoma. We believe that this antibody will be of value in the characterization of malignant lymphoma, in particular the differential diagnosis of small-B-cell lymphoma and subtyping of lymphoblastic leukemia, as well as the investigation of the significance of expression of CD10 in other normal and pathological tissues.  相似文献   
433.
As the 20th century draws to a close, fundamental changes in the organization, financing, and delivery of health care and welfare services, principally directed at poor families, are likely to result in an increased number of children entering out-of-home care. These children typically have significant physical, mental health, and developmental problems. Whether the quality of health care services they receive will improve as a result of health care reform efforts and new approaches to service delivery remains to be seen. This article addresses some of the major changes wrought by welfare and health care reform and describes the essential features of a health care system that can meet the special needs of children in care.  相似文献   
434.
Feces collected from three asymptomatic horses and seeded with Cryptosporidium parvum oocysts (10(1) to 10(6)/g of feces) were evaluated by acid-fast staining (AF), an immunofluorescent antibody (IFA) technique, and flow cytometry. The thresholds of detection were 5 x 10(5) oocysts/g of feces for the IFA and AF techniques and 5 x 10(4) oocysts/g for flow cytometry.  相似文献   
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436.
Thiazolidinediones are oral insulin-sensitizing agents that may be useful for the treatment of non-insulin-dependent diabetes mellitus (NIDDM). BRL 49653 ameliorates insulin resistance and improves glucoregulation in high-fat-fed (HF) rats. It is known that thiazolidinediones bind to the peroxisome proliferator-activated receptor (PPAR gamma) in fat cells, but the extent to which the improved glucoregulation and hypolipidemic effects relate to adipose tissue requires clarification. We therefore examined BRL 49653 effects on lipid metabolism in HF and control (high-starch-fed [HS]) rats. The diet period was 3 weeks, with BRL 49653 (10 mumol/kg/d) or vehicle gavage administered over the last 4 days. Studies were performed on animals in the conscious fasted state. In HF rats, rate constants governing 3H-palmitate clearance were unaffected by BRL 49653. This finding, taken with a concurrent decrease of fasting plasma nonesterified fatty acids (NEFA) (P < .01, ANOVA), demonstrated that systemic NEFA supply and hence absolute utilization are reduced by BRL 49653. Hepatic triglyceride (TG) production (HTGP) assessed using Triton WR1339 was unaffected by diet or BRL 49653. In liver, BRL 49653 increased insulin-stimulated conversion of glucose into fatty acid in both HF (by 270%) and HS (by 30%) groups (P < .05). Relative to HS rats, HF animals had substantially elevated levels of muscle diglyceride (diacylglycerol[DG] by 240%, P < .001). BRL 49653 significantly reduced muscle DG in HF (by 30%, P < .05) but not in HS rats. The agent did not reduce the intake of dietary lipid. In conclusion, these results are consistent with a primary action of BRL 49653 in adipose tissue to conserve lipid by reducing systemic lipid supply and subsequent utilization. The parallel effects of diet and BRL 49653 treatment on insulin resistance and muscle acylglyceride levels support the involvement of local lipid oversupply in the generation of muscle insulin resistance.  相似文献   
437.
The present study investigated the spontaneous, unintended body weight changes observed during the first 11 weeks of an eight months' ad libitum low-fat/high-fibre diet (25.5 energy-% fat, 58.5 energy-% carbohydrate, 3.9 g dietary fiber/MJ), primarily aimed at investigating changes in blood lipid concentrations. Subjects were normal-weight, young, healthy students, 24 in the intervention group, and 24 in the control group (no diet). After 11 weeks, an overall decrease in body weight (1.3 +/- 0.4 kg) (mean +/- SEM) (p < 0.01) and fat mass (1.6 +/- 0.2 kg, p < 0.001) was observed in the intervention group. Fat-free mass remained unchanged. Initial body weight and fat mass correlated significantly to changes in body weight and fat mass. No changes were observed in the control group. In conclusion, the ad libitum intake of a low-fat/high-fibre diet led to a spontaneous, small loss of body weight and fat mass in young, normal-weight subjects.  相似文献   
438.
F Abbasakoor  JM Manson  AR Morgan  J Beynon  ND Carr 《Canadian Metallurgical Quarterly》1997,84(10):1482; author reply 1483-1482; author reply 1484
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