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81.
Transurethral electrovaporization of the prostate (TVP) is a new minimally invasive procedure for treatment of enlargement of prostate. Between April 1996 and September 1997, TVP was carried out in 109 cases with symptoms of lower urinary tract obstruction. A Stortz spike electrode and a Stortz vapor cutting electrode were used for vaporization electrodes. Efficacy parameters evaluated included International Prostate Symptom Score, peak uroflow and postvoid residual volume. By September 1997, 32 cases (spike electrode) and 33 cases (vapor cutting electrode) could be followed up and evaluated. They have shown both subjective and objective voiding improvement. The improvements in subjective symptom scores and objective voiding parameters were not significantly different between the two electrode groups. Early complications included urinary retention, intraoperative burn, stress incontinence, blood transfusion and postoperative hemorrhage. Late complications included urethral stricture, bladder neck contracture and bladder stone. TVP was found to have several advantages, particularly minimal bleeding and the low incidence of postoperative morbidity. The technique is simple and symptoms improve at an early stage following surgery. This study demonstrates that TVP is a safe and effective modality for treatment of BPH. However, long-term studies with larger numbers of patients are needed.  相似文献   
82.
In summary, the National Database Committee's Audit and Validation Subcommittee is working to maximize the data completeness and quality of the STS National Database. Toward this end, we welcome your suggestions for improvement.  相似文献   
83.
The frequent occurrence of degenerative joint disease following complete or partial meniscectomy is well recognized. Meniscal repair has been shown to lead to a lower prevalence of degenerative changes in the knee. Arthroscopically assisted inside-to-outside meniscal repair is a safe, reproducible technique for for salvaging the torn meniscus.  相似文献   
84.
The involvement of the protein kinase C substrate, B-50 (GAP-43), in the release of glutamate from small clear-cored vesicles in streptolysin-O-permeated synaptosomes was studied by using anti-B-50 antibodies. Glutamate release was induced from endogenous as well as 3H-labelled pools in a [Ca(2+)]-dependent manner. This Ca(2+)-induced release was partially ATP dependent and blocked by the light-chain fragment of tetanus toxin, demonstrating its vesicular nature. Comparison of the effects of anti-B-50 antibodies on glutamate and noradrenaline release from permeated synaptosomes revealed two major differences. Firstly, Ca(2+)-induced glutamate release was decreased only partially by anti-B-50 antibodies, whereas Ca(2+)-induced noradrenaline release was inhibited almost completely. Secondly, anti-B-50 antibodies significantly reduced basal glutamate release, but did not affect basal noradrenaline release. In view of the differences in exocytotic mechanisms of small clear-cored vesicles and large dense-cored vesicles, these data indicate that B-50 is important in the regulation of exocytosis of both types of neurotransmitters, probably at stages of vesicle recycling and/or vesicle recruitment, rather than in the Ca(2+)-induced fusion step.  相似文献   
85.
BACKGROUND/AIMS: The number of perisinusoidal myofibroblasts has been shown to be increased in hepatocellular carcinoma, as compared to cirrhosis. This increase might suggest a cooperative relationship between tumour cells and myofibroblasts. To assess this relationship, we undertook: (a) an immunohistochemical study to confirm the existence of an increased number of perisinusoidal myofibroblasts in human hepatocellular carcinoma, as compared to cirrhosis with or without liver cell dysplasia, (b) an in vitro study testing the role of normal or tumoral human hepatocytes in myofibroblast proliferation. METHODS: Forty explanted cirrhotic livers, including 14 with hepatocellular carcinoma and 24 with liver cell dysplasia, were studied. Myofibroblasts were detected by immunohistochemistry using an antibody directed against alpha-smooth muscle actin. Hepatic myofibroblasts in culture were obtained by outgrowth from human liver explants. RESULTS: There was a progressive increase in the number of perisinusoidal myofibroblasts, from cirrhotic nodules without dysplasia to liver cell dysplasia and hepatocellular carcinoma. Conditioned medium from isolated normal human hepatocytes had only minor mitogenic effects on myofibroblasts, as assessed by measuring DNA synthesis and cell growth. In contrast, conditioned medium from a human hepatoma cell line (HepG2 cells) markedly stimulated the proliferation of human myofibroblasts. This mitogenic activity was stored in HepG2 cells and secreted in the extracellular medium rather than being simply released following cell lysis. CONCLUSIONS: These results suggest that the increased number of myofibroblasts in hepatocellular carcinoma might be due to a paracrine mechanism involving soluble mitogenic factor(s) secreted by tumour cells.  相似文献   
86.
Primary palatogenesis in mice is similar to that in humans, and spontaneous cleft lip appears to be multifactorially determined in both. Binding of a ligand to erbB4 has been shown to stimulate the receptor's protein kinase activity, which subsequently stimulates a signal-transduction cascade leading to cell growth and differentiation, and to morphogenesis during development. In this study, an immunohistochemical technique was used to investigate the temporal and spatial expression of erbB4 in the primary palate of cleft (A/WySn) and noncleft strains of mice (BALB/cBy). Positive staining of erbB4 was found in ectodermal and mesenchymal cells of facial prominences before the primary palate formation stage (day 10, hour 20) in both strains. During the primary palate formation stage (day 11, hour 20), positive staining of erbB4 was found in the ectodermal and mesenchymal cells of the facial prominences of the noncleft strain, but not in those of the cleft strain. These results suggest erbB4 expression may be associated with normal primary palatogenesis of mice and, conversely, cleft lip may be associated with a deficiency of erbB4 expression during primary palate formation in mice.  相似文献   
87.
One year after a nonspecific trauma and with a history of pain of four weeks only, an osteoid osteoma of the first phalanx of the left thumb was diagnosed in a 31-year-old man. The radiologic appearance as well as a bone scan were suggestive for an osteoid osteoma. The diagnosis was confirmed histologically after resection of the tumor. As indicated in the literature, osteoid osteoma of the hand is relatively rare. The symptoms and radiologic features (osteolytic nidus and sclerosis) of osteoid osteomas are independent of the tumor location. Surgery with resection of the nidus is the only known curative therapy. The etiological role of trauma is discussed and a review of the literature is done with 15 other cases of posttraumatic osteoid osteoma having been reported.  相似文献   
88.
We have used a transgene mutation approach to study how expression domains of Hoxc8 are established during mouse embryogenesis. A cis-regulatory region located 3 kb upstream from the Hoxc8 translational start site directs the early phase of expression. Four elements, termed A, B, C, and D, were previously shown to direct expression to the neural tube. Here we report that a fifth element, E, located immediately downstream of D directs expression to mesoderm in combination with the other four elements. These elements are interdependent and partially redundant. Different combinations of elements determine expression in different posterior regions of the embryo. Neural tube expression is determined minimally by ABC, ABD, or ACD; somite expression by ACDE; and lateral plate mesoderm expression by DE. Neural tube and lateral plate mesoderm enhancers can be separated, but independent somite expression has not been achieved. Furthermore, mutations within these elements result in posteriorization of the reporter gene expression. Thus, the anterior extent of expression is determined by the combined action of these elements. We propose that the early phase of Hoxc8 expression is directed by two separate mechanisms: one that determines tissue specificity and another that determines anterior extent of expression.  相似文献   
89.
90.
BACKGROUND: Aspergillosis is an uncommon yet serious opportunistic infection in patients with AIDS. It has been extensively reported in HIV-infected adult patients. To our knowledge there are no studies that describe the epidemiology, clinical manifestations and outcome of aspergillosis in a large HIV-infected pediatric population. METHODS: We reviewed the records of all 473 HIV-infected children followed in the Pediatric Branch of the National Cancer Institute for 9 years from 1987 through 1995 for the presence of Aspergillus infection. RESULTS: Seven (1.5%) patients developed invasive aspergillosis during the study period. All patients had low CD4 counts reflecting severe immunosuppression. Sustained neutropenia (> 7 days) or corticosteroid therapy as a predisposing factor for invasive aspergillosis was encountered in only two patients (28%). Invasive pulmonary aspergillosis developed in five patients and cutaneous aspergillosis in two. The most common presenting features in patients with pulmonary aspergillosis were fever, cough and dyspnea. Patients with cutaneous aspergillosis were diagnosed during life and successfully treated with amphotericin B and surgery, whereas diagnosis of pulmonary aspergillosis was made clinically in only one patient. CONCLUSIONS: Aspergillosis is an uncommon but highly lethal opportunistic infection in HIV-infected children. Invasive pulmonary aspergillosis should be considered in the differential diagnosis in febrile, HIV-infected children with persistent pulmonary infiltrates.  相似文献   
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