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41.
The role of radical cystectomy as the standard treatment of localised infiltrating bladder malignancy is challenged by the development radiotherapy and chemotherapy combinations. The published studies are difficult to compare because of large differences in the patients selection criteria and in the assessment of local involvement (only clinical in combined treatment, based on pathology and therefore unquestionable in surgical series). The advantages of radical surgery are its precedence and a well-established technique, simplified follow-up procedures and seemingly higher survival rates acquired after 3 years. Conversely, the combination of radiotherapy and chemotherapy allows bladder preservation in about 40% of the patients (at 5 years), but only in 23% without bladder relapses. A complete initial endoscopic resection is the best and only prognostic factor of these results which nevertheless needs a very carefully and endless follows. The comparison of the quality of life achieved by both treatment modalities remains insufficiently documented.  相似文献   
42.
OBJECTIVES: To determine whether oxytocin exists in the cerebrospinal fluid (CSF) of dogs and whether the amount of oxytocin in the CSF of dogs with neck or back pain caused by spinal cord compression is significantly different than that in the CSF of clinically normal dogs. STUDY DESIGN: Prospective controlled study. ANIMAL POPULATION: A total of 15 purpose-bred beagles and 17 client-owned dogs. METHODS: CSF was collected by needle puncture of the cerebellar medullary cistern after induction of general anesthesia. Oxytocin levels within the samples were determined through radioimmunoassay. RESULTS: Dogs with spinal cord compression had significantly more oxytocin in their CSF than the clinically normal dogs (13.76 +/- 2.0 pg/mL and 3.61 +/- 0.63 pg/mL, respectively; P < .0001). Dogs with chronic signs (>7 days) had significantly more oxytocin in their CSF than dogs with acute signs (<7 days) (21.60 +/- 0.86 pg/mL and 6.80 +/- 0.81 pg/mL, respectively; P < .0001). Both acutely and chronically affected dogs had significantly more oxytocin in their CSF than the controls (P < .005 and P < .0001 respectively). CONCLUSIONS: Dogs with neck and back pain caused by spinal cord compression have significantly more oxytocin in their CSF than clinically normal dogs. Dogs with chronic clinical signs have significantly more oxytocin in their CSF than dogs with acute clinical signs. CLINICAL RELEVANCE: In humans, intrathecal injection of oxytocin is effective in treating low back pain for up to 5 hours. Intrathecal oxytocin may be a logical choice for perioperative analgesia in dogs undergoing myelography because the intrathecal space is accessed for injection of contrast agent.  相似文献   
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AIM OF THE STUDY: To study the changes in nasal reactivity in patients with rhinitis medicamentosa during treatment with placebo or fluticasone propionate, in order to better understand the mechanisms of nasal congestion in such patients. STUDY DESIGN: A parallel, double-blind study. Twenty patients with rhinitis medicamentosa were randomized to either placebo or fluticasone treatment during 14 days. MATERIAL AND METHODS: Nasal mucosa reactivity was studied with a histamine challenge model using three concentrations of histamine to challenge the nasal mucosa (1, 2 and 4 mg histamine/ml). Recordings of the nasal mucosa response were made 5 min after each challenge, using rhinostereometry and acoustic rhinometry, before and after the period of treatment. RESULTS: The fluticasone group had a significantly increased histamine sensitivity after treatment, unlike the placebo group who had an unchanged or slightly decreased histamine sensitivity after treatment. CONCLUSIONS: The results of this study support the theory that the nasal obstruction in rhinitis medicamentosa is due to interstitial oedema rather than to vasodilatation. On the first day of vasoconstrictor withdrawal, the inferior concha was congested and oedematous with a limited capacity to respond to histamine challenge. However, after 14 days of treatment with a corticosteroid nasal spray, the oedema was reduced and the increase in histamine sensitivity reflected the persistence of nasal hyperrreactivity. In the placebo group, histamine sensitivity remains unchanged with the measuring technique we used. This probably indicates that oedema was still present after treatment.  相似文献   
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The association patterns between maternal anthropometric characteristics (stature, prepregnancy weight, prepregnancy body mass index, pregnancy weight gain) and newborn size (birth weight, length, head circumference) were tested with 10,240 single births taking place between 1985 and 1995 in Vienna, Austria, and 3,452 single births taking place between 1989 and 1995 in Westerstede-Ammerland (Friesland), northern Germany. Maternal size and newborn size differed highly significantly (p < 0.001) between the two genetically and socioeconomically different population groups. Furthermore, the incidence of macrosomia among newborns (birth weight greater than 4000 g) was extraordinarily high (17.9%) in the Frisian group from northern Germany. In both populations taller and heavier women with a higher weight gain during pregnancy gave birth to heavier offspring. Nevertheless, the pregnancy weight gain, which indicates environmental conditions of the mother, had only a minor impact on newborn size compared with stature and prepregnancy weight, which reflect the maternal genetic potential to a higher degree.  相似文献   
47.
The use of bone grafts is the basis of all craniofacial surgery. Bone grafts are used to stabilize the open segments, expand the patient's structural boundaries, and fill defects created by trauma or congenital malformations. Bone grafts are harvested from local or distant sites as indicated. Biomaterial implants are used as bone substitutes when it is not possible to use bone grafts.  相似文献   
48.
Lymphocyte subset abnormalities have been observed in a series of patients diagnosed with Wegener's granulomatosis (WG). Fifteen patients with WG were evaluated for lymphocyte subset abnormalities by two-color immunofluorescence flow cytometry. The WG group showed a decrease in CD4+ cells and an extraordinary increase in HLA-DR+ cells. The average percentages of HLA-DR+ cells of the normal group and WG group were 11.0 +/- 4.0 and 40.5 +/- 13.9% (CD3+HLA-DR+ = 20.3 + 9.4%). Within the CD8 family, CD8+57+, CD8+38+ and CD8+HLA-DR+ cells were markedly elevated. Our findings differ from other series which reported that the lymphocyte subsets in the peripheral blood of patients with WG were normal.  相似文献   
49.
OBJECTIVE: To examine the changes in neutrophil deformability, aggregation, and adherence in response to stimulation with proinflammatory cytokines and bacterial toxins. DESIGN: Prospective, randomized trial. SETTING: Research laboratory. SUBJECTS: Neutrophils isolated from healthy volunteers. INTERVENTIONS: Neutrophils were exposed to tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-8, their combination, endotoxin (LPS), lipoteichoic acid (LTA), and staphyloccocal enterotoxin B (SEB). Neutrophil deformability was measured as percent neutrophils filtered through 5-microm diameter filters. Aggregation was measured using a platelet aggregometer. Adherence was determined by examining the binding of neutrophils to albumin-coated latex beads. MEASUREMENTS AND MAIN RESULTS: Exposure to TNF-alpha and IL-1beta led to significant decreases in neutrophil filterability, which was attenuated by cytochalasin D pretreatment. LPS and LTA also decreased deformability, suggesting that these toxins directly stimulated neutrophils independent of cytokines. IL-8 and SEB did not significantly affect neutrophil deformability. TNF-alpha and LPS were associated with significant neutrophil aggregation, which was inhibited by pretreatment with anti-CD18 antibodies. Neutrophil aggregation was not affected by IL-1beta, LTA, or SEB. TNF-alpha, IL-8, and LPS increased neutrophil adherence, which also was attenuated by pretreatment with anti-CD18 antibodies. IL-1beta, LTA, and SEB did not significantly affect neutrophil adherence. CONCLUSIONS: Cytokines and bacterial toxins differ in their effects on neutrophil deformability, aggregation, and adherence. Of the cytokines examined, TNF-alpha appears to have the greatest direct effects on neutrophil rheology. Similarly, endotoxin appears to have greater direct effects on neutrophil rheology than the Gram-positive bacterial toxins, LTA, and staphylococcal enterotoxins.  相似文献   
50.
Efforts to classify the hereditary ataxias by their clinical and neuropathological phenotypes are troubled by excessive heterogeneity. Linkage analysis opened the door to a new approach with the methods of molecular biology. The classic form of autosomal recessive ataxia, Friedreich's ataxia (FA), is now known to be due to an intronic expansion of a guanine-adenine-adenine (GAA)-trinucleotide repeat. The autosomal dominant ataxias such as olivopontocerebellar atrophy (OPCA), familial cortical cerebellar atrophy (FCCA), and Machado-Joseph disease (MJD) have been renamed the spinocerebellar ataxias (SCA). Specific gene loci are indicated as SCA-1, SCA-2, SCA-3, SCA-4, SCA-5, SCA-6, and SCA-7. In 5 of them (SCA-1, SCA-2, SCA-3, SCA-6, and SCA-7), expanded cytosine-adenine-guanine (CAG)-trinucleotide repeats and their abnormal gene products cause the ataxic condition. The most common underlying loci for olivopontocerebellar atrophy (OPCA) are SCA-1 and SCA-2, although other genotypes may be added in the future. A major recent advance was the identification of the gene for SCA-3 and MJD, and the high prevalence of this form of autosomal dominant ataxia. In FA and the SCA with expanded CAG-trinucleotide repeats, clinical and neuropathological severity are inversely correlated with the lengths of the repeats. Anticipation in the dominant ataxias can now be explained by lengthening of the repeats in successive generations. Progress is being made in the understanding of the pathogenesis of FA and SCA as the absent or mutated gene products are studied by immunocytochemistry in human and transgenic murine brain tissue. In FA, frataxin is diminished or absent, and an excess of mitochondrial iron may cause the illness of the nervous system and the heart. In SCA-3, abnormal ataxin-3 is aggregated in neuronal nuclei, and in SCA-6, a mutated alpha1A-calcium channel protein is the likely cause of abnormal calcium channel function in Purkinje cells and in the death of these neurons.  相似文献   
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