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991.
We report a case of granulomatous mycosis fungoides that progressed into fatal gastrointestinal involvement 4 years after the onset of skin lesions, despite improvement of the skin lesions in response to a combination of PUVA and systemic interferon-gamma therapy. Histological examination showed Pautrier's microabscesses with granuloma annulare-like features and sarcoidal granuloma formation in the plaque stage, proliferation of blast-transformed atypical lymphocytes with persistent granuloma formation in the tumour stage, and metastatic lesions. A literature review of granulomatous mycosis fungoides revealed that 11 of the 24 reported cases died of the disease, and like our case, seven died within 5 years. We suggest that mycosis fungoides with granulomatous reactions does not indicate a favourable prognosis. 相似文献
992.
Matthews P.J. Berenc T. Schoenfeld F. Feinerman A.D. Kang Y.W. Kustom R. 《Microwave Theory and Techniques》1996,44(8):1401-1409
Perturbational field strength measurements suitable for use on a proposed 120-GHz 50-MeV electron linear accelerator are described. The measurements are used to determine the R/Q of the device, where R is the shunt impedance. The perturbation is achieved by the use of hollow metallic cylinders with diameters ranging from 25 to 127 μm which are approximately 500 μm long. The cylinders were fabricated by sputtering aluminum through a shadow mask onto silica optical fibers as well as nylon surgical thread. The perturbational “form factors” for such a geometry are experimentally determined using a pillbox cavity. The measured values for the form factors are compared to theoretical estimations, which result in simple analytical expressions. The measured form factors are also compared to values calculated from a finite difference model of the perturbing object. The R/Q for various accelerating modes is measured on a 12-GHz model of the 120-GHz structure. Results are compared to predictions from a finite difference model of the accelerating structure 相似文献
993.
OBJECTIVE: The aim of this study was to evaluate the effectiveness of fine-needle aspiration (FNA) in the diagnosis of primary lymphoid processes of the salivary gland. DESIGN: A retrospective study. METHOD: Between 1987 and 1994, 35 patients who underwent fine-needle aspiration (FNA) of the salivary gland had a diagnosis of a primary lymphoid process. Most presented with palpable parotid (28 patients) or submandibular (4 patients) gland masses which prompted a clinical diagnosis of pleomorphic adenoma. FNA was performed with immediate on-site evaluation. Flow cytometric cell-surface-marker analysis was performed in 28 of the 35 cases to determine the clonality of the B-cell proliferations. RESULTS: Sixteen cases of reactive hyperplasia and nine cases of malignant lymphoma diagnosed by FNA were confirmed by subsequent histopathologic examination. Lymphoma was confirmed in six of eight cases diagnosed as suspicious for lymphoma by FNA. Hodgkin's disease was suspected but not confirmed in one case and was diagnosed as a probable Warthin's tumour in another case. In all cases, the FNA diagnosis of either a reactive or malignant lymphoid process was unexpected and influenced the patient's further management. For patients diagnosed with an intraparotid lymph node, surgery could be deferred for a short period with the hope that the lymphadenopathy would spontaneously regress. For patients with a preoperative FNA diagnosis of lymphoma, a more limited biopsy could be performed, thereby reducing the operative risk to the patient and plans to process the tissue according to the institution's lymphoma protocol could be made. CONCLUSION: Clinically, reactive intraparotid lymph nodes and lymphomas present as parotid enlargements that are indistinguishable from pleomorphic adenomas. FNA is the only method of accurately establishing a preoperative diagnosis in these patients. 相似文献
994.
The limbic system seems to be involved in the pathophysiology of neuropsychiatric disorders, including dementia, schizophrenia, affective disorders, and amnestic disorders. These findings are subtle and largely went undetected until the advent of modern neuroimaging. This article discusses some of the neuroimaging findings in these disorders. 相似文献
995.
MF Beal RJ Ferrante SE Browne RT Matthews NW Kowall RH Brown 《Canadian Metallurgical Quarterly》1997,42(4):644-654
The pathogenesis of neuronal degeneration in both sporadic and familial amyotrophic lateral sclerosis (ALS) associated with mutations in superoxide dismutase may involve oxidative stress. A leading candidate as a mediator of oxidative stress is peroxynitrite, which is formed by the reaction of superoxide with nitric oxide. 3-Nitrotyrosine is a relatively specific marker for oxidative damage mediated by peroxynitrite. In the present study, biochemical measurements showed increased concentrations of 3-nitrotyrosine and 3-nitro-4-hydroxyphenylacetic acid in the lumbar and thoracic spinal cord of ALS patients. Increased 3-nitrotyrosine immunoreactivity was observed in motor neurons of both sporadic and familial ALS patients. Neurologic control patients with cerebral ischemia also showed increased 3-nitrotyrosine immunoreactivity. These findings suggest that peroxynitrite-mediated oxidative damage may play a role in the pathogenesis of both sporadic and familial ALS. 相似文献
996.
BACKGROUND: Patients whose brain metastases from breast cancer are treated nonsurgically have a median length of survival ranging from 2.5 to 7.5 months, and a median time to recurrence ranging from 2 to 5 months. Patients treated with radiotherapy have a median length of survival ranging from 3 to 4 months. Those treated with chemotherapy have a median length of survival ranging from 5.5 to 7.5 months. METHODS: We conducted a retrospective analysis on 63 patients treated over a 10-year period. Only patients who underwent surgery for nonrecurrent brain metastases were studied. Sixty-one patients (97%) underwent surgery within 2 weeks of diagnosis of the brain metastases. RESULTS: The median length of survival was 16 months (95% confidence interval [CI] 11 to 22 months), and the 5-year survival rate was 17% (CI 9% to 29%). Brain metastases recurred in 27 patients at a median interval of 15 months (CI 12 to 24 months). Eleven patients had local recurrence, 10 had distal recurrence, and seven developed leptomeningeal disease. Significant prognosticators of length of survival were age (p = 0.011), menopause status (p = 0.10), postoperative radiotherapy (p = 0.054), preoperative neurologic status (p = 0.011), and preoperative systemic disease status (p = 0.0003). Systemic disease status had a significant effect on the length of survival but not on the time to recurrence. 相似文献
997.
FR Spitz GG Giacco K Hess L Larry TA Rich N Janjan KR Cleary JM Skibber 《Canadian Metallurgical Quarterly》1997,3(10):1685-1690
This study was conducted to investigate the value of p53 immunohistochemical staining of pretreatment biopsy specimens in predicting the response of rectal cancer to chemoradiation. The study group comprised 42 patients with high-risk rectal cancer treated between July 1990 and July 1995 with a preoperative chemoradiation regimen of 45 Gy of external-beam irradiation and continuous-infusion 5-fluorouracil followed by surgical resection. p53 immunohistochemical staining was performed on pretreatment biopsy specimens. p53 immunohistochemical staining pattern and standard clinical and pathological parameters were correlated with extent of residual cancer in the surgical specimen. Twenty tumors were positive for p53 on immunohistochemical staining, 19 were negative, and 3 were focally positive. Thirteen patients experienced a complete response to chemoradiation. Aberrant p53 protein accumulation, as measured by immunohistochemical staining, correlated inversely with a complete pathological response to chemoradiation (P = 0.005; correlation coefficient = -0.43) and directly with an increased likelihood of residual cancer in the lymph nodes of surgical specimens (P = 0.02; correlation coefficient = 0.39). p53 immunohistochemical staining of pretreatment biopsy specimens correlates with the extent of residual disease after chemoradiation in patients with high-risk rectal cancer. 相似文献
998.
999.
The authors hypothesized that having traits associated with the female gender role is related to psychological distress in women. Specifically, they investigated the effect of low instrumentality and high expressivity, private self-consciousness, and anger-in on depressive symptoms measured 3 years later in 460 middle-aged women during the menopausal transition and times of stress. Multivariate analyses showed that after adjustment for depressive symptoms and educational level at study entry, depressive symptomatology 3 years later was higher among women who were low in instrumentality and high in self-consciousness at study entry. Women who were self-conscious were the most vulnerable to a subsequent ongoing stressor, and women who tended to suppress angry feelings and who used hormone replacement therapy when they were postmenopausal had more symptomatology than did other women. The study showed that midlife may be problematic for women with certain female gender role traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
The present study was carried out to investigate the relationship between elastase and monocrotaline (MCT)-induced ventilatory dysfunction in rats. To accomplish this, we used an elastase inhibitor eglin-c to suppress the activity of endogenous elastase. Thirty-five young Sprague-Dawley rats were randomly divided into six groups: control, MCT, eglin-c(1), eglin-c(2), eglin-c(1) + MCT, and eglin-c(2) + MCT. Rats in the control group received no treatment. Each MCT rat received a single subcutaneous injection of MCT (60 mg/kg) 1 wk before the functional test. Each eglin-c(1) rat was intratracheally instilled with eglin-c (9 mg/rat) twice in 1 wk. Each eglin-c(2) rat was intratracheally instilled with eglin-c (9 mg/rat) five times in 1 wk. Both eglin-c + MCT groups were treated with the combination of eglin-c(1) or eglin-c(2) and MCT. In the MCT group, there were significant decreases in dynamic respiratory compliance, maximal expiratory flow rate at 50% total lung capacity, and the slopes of the maximal expiratory flow-%total lung capacity curve and the maximal expiratory flow-static recoil pressure curve. However, in the eglin-c(1) + MCT and eglin-c(2) + MCT groups, all of the above-mentioned MCT-induced changes were prevented. All ventilatory values of the eglin-c(1) and eglin-c(2) groups were not significantly different from those of the control group. These results demonstrate that eglin-c treatment prevents MCT-induced ventilatory dysfunction and suggest that endogenous elastase may play an important role in MCT-induced inflammation-mediated ventilatory abnormality. 相似文献