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111.
Systemic lupus erythematosus (SLE) is an inflammatory systemic disease that causes organ damage by the deposition of autoantibodies and complement activating immune complexes or by vascular occlusion due to procoagulant states associated with antiphospholipid antibodies. The vast majority of cases occur in women of childbearing age. SLE is diagnosed on the basis of its clinical manifestations and the demonstration of characteristic immunological phenomena, especially anti-nuclear antibodies. The prognosis in SLE has shown a distinct improvement over recent decades, the 5-year survival rate now approaching or exceeding 90%. The 15-year survival rate of 63 to 79%, on the other hand, underscores the need for further advances in diagnosis and treatment of the disease. Management of the disease includes regular monitoring of disease activity, avoidance of predisposing factors and close supervision of therapy. Drug therapy is guided by the activity and severity of the leading organ manifestations and ranges from nonsteroidal antirheumatic drugs to intensive treatment with cytotoxic agents. Corticosteroids remain irreplaceable for the control of acute flares. Antimalarials and azathioprine are important long term drugs for treating mild or moderate disease activity. Intravenous pulse cyclophosphamide is safer than other regimens and at least as effective as oral cyclophosphamide for severe lupus nephritis. It is also effective in the treatment of central nervous disease and of other organ-threatening manifestations. Recently, an intensified protocol which included cyclophosphamide induced long term treatment-free remission in 60% of patients. The toxicity of cyclophosphamide is considerable, but can be ameliorated by various measures. The value of several new immunosuppressants and other compounds remains to be determined.  相似文献   
112.
Gastrointestinal carcinoid tumor is often considered the most common neuroendocrine tumor of the small intestine. The overall incidence of 1% in the general population is quite low. Extraadrenal paragangliomas are rarer still, and the incidence of both of these tumors in the malignant state is exceedingly rare. This article describes the case of a patient who had both a malignant carcinoid tumor as well as a malignant retroperitoneal paraganglioma occurring synchronously. A review of the literature concerning these tumors is also presented.  相似文献   
113.
A variety of initiation procedures have been used to develop oral ethanol consumption. Using the sucrose-substitution procedure, oral self-administration of ethanol-water solutions with ethanol concentrations as high as 40% can be initiated in food- and fluid-sated rats. An important question for these models is the relationship between ethanol concentration and self-administration patterns after initiation. This study examined the differential patterns of ethanol self-administration maintained by a range of ethanol solutions (10 to 30%) over a 5-week period, compared with rats maintained on 10% ethanol for 5 weeks. In 43 male Long Evans rats, the sucrose-substitution procedure was used to initiate responding maintained by 10% ethanol on a Fixed Ratio 4 schedule of reinforcement. The ethanol concentration presented was then increased to 30% in stepwise fashion and then returned to 10% [Ethanol Concentration Manipulation (ECM) group, n = 32], or 10% ethanol was maintained as the reinforcer for 5 weeks [Control (Con) group, n = 11]. Significant increases in ethanol intake and decreases in responding were associated with increased ethanol concentration. Although no overall differences in total session responding were observed in either group between week 1 and week 5 (10E vs. 10E), examination of changes in initial low responders of the ECM group revealed significant increases in responding that were not observed in the initial low responders of the Con group. Significant increases in momentary response rates were observed on both the ECM and Con groups, independent of the ethanol concentration presented. Increases in response rate in the ECM group were the result of increases in initial low rate and high rate responders; however, the increased response rates in the Con group were the result of increases only in the initial low rate responders. These data suggest that the ECM procedure can aid in the initiation of ethanol self-administration and may be particularly useful in rats of heterogeneous stock.  相似文献   
114.
115.
Heterotrimeric G proteins have been implicated in the regulation of intracellular protein transport, but their mechanism of action remains unclear. In vivo, secretion of chromogranin B, tagged with the green fluorescent protein, was inhibited by the addition of a general activator of trimeric G proteins (AlF4-) to stably transfected Vero cells and resulted in an accumulation of the tagged protein in the Golgi apparatus. In an in vitro assay that reconstitutes intra-Golgi protein transport, we find that a membrane-bound and AlF4--sensitive factor is involved in the fusion reaction. To determine whether this effect is mediated by a heterotrimeric G protein localized to COPI-coated transport vesicles, we determined the presence of G proteins on these vesicles and found that they were segregated relative to the donor membranes. Because G proteins do not have an obvious sorting, retention, or retrieval signal, we considered the possibility that other interactions might be responsible for this segregation. In agreement with this, we found that trimeric G proteins from isolated Golgi membranes were partially insoluble in Triton X-100. Identification of the proteins that interact with the heterotrimeric G proteins in the Golgi-derived detergent-insoluble complex might help to reveal the regulation of protein secretion mediated by heterotrimeric G proteins.  相似文献   
116.
BACKGROUND: The risk and outcome in patients undergoing left ventricular assist device (LVAD) implantation on an emergency basis is still unclear. METHODS: Since April 1993, 40 patients received a Novacor and 8 patients a Heartmate LVAD in our institution. Patients with emergency LVAD placement were compared with the remainder in a retrospective manner. Parameters studied included underlying heart disease, preimplantation dysfunction of kidney, liver, lung, and cerebrum, interval of mechanical support, outcome, and complications. RESULTS: Patients with emergency LVAD placement predominantly were seen with postcardiotomy heart failure (47%) or acute myocarditis (20%) (group A) whereas elective and urgent candidates for LVAD implantation mainly had dilative cardiomyopathy (67%) or ischemic heart disease (30%) (group B). The incidence of secondary organ failure was significantly higher for all organs in group A patients (p < .01). Mean support interval in patients who underwent emergency LVAD implantation was lower (74+/-79 days vs 115+/-80 days), and fewer patients could be forwarded to heart transplantation in this group (22% vs 78%, p < .01). Moreover, bleeding complications were increased in group A (66% vs 30%, p < .01), but not thromboembolism and infection. CONCLUSION: In conclusion, the overall success rate after emergency LVAD implantation was lower, with bleeding being the most frequent complication. To achieve acceptable outcomes in disastrous situations, LVADs should be placed as early as possible.  相似文献   
117.
Rats experience anorexia and reduction or cessation in growth after being provided a zinc-deficient diet. While zinc deficient, intake levels may be reduced 50% or more compared to control rats. In the present report, diurnal food intake patterns of male Sprague-Dawley rats were measured during zinc deficiency. In Study 1, rats consuming a modified AIN-93 diet were tested during the dark phase using an automated food weighing system. In zinc-deficient animals (Zn-), the onset of the first meal of the dark phase was delayed compared to zinc-adequate rats (Zn+; 106+/-47 vs. 23+/-5 min; p<0.05) and the number of meals consumed during the dark phase was reduced in Zn- vs. Zn+ rats (3.9+/-0.5 vs 7.1+/-0.4; p<0.05). In Study 2, diurnal food intake patterns were tested using a three-choice macronutrient self-selection paradigm of carbohydrate-, protein-, and fat-containing diets made deficient or adequate in zinc (1 or 30 mg Zn/kg diet). Food intake was recorded in the early-, mid-, late-dark period (4 h each) and light period (12 h). Carbohydrate intake was 70% of total intake of both Zn+ and Zn- rats during the first 5 days, but decreased significantly to 50% in the Zn- group during the last 5 days. Fat intake increased significantly in the Zn- group during the last 5 days. This increase was the result of 4 of 15 Zn- rats increasing their intake of fat significantly. Results of this study indicate that zinc status alters dark phase and macronutrient selection patterns by delaying consumption of the initial meal of the dark phase, reducing the average meal number and by changing the dominant macronutrient preference of some Zn- rats.  相似文献   
118.
Typical and atypical carcinoids (TC, ATC) and small (SCLC) and large cell neuroendocrine carcinomas (LCNEC) constitute the spectrum of neuroendocrine lung tumors. Chromosomal aberrations have not been studied in LCNEC and only rarely in carcinoids. Only SCLCs have been investigated frequently for chromosomal aberrations. We compared three typical and four atypical carcinoids, one atypical carcinoid/SCLC mixed type, three SCLC, and three LCNEC for chromosomal gains and losses using comparative genomic hybridization. Typical carcinoids showed either no changes or only few chromosomal gains. Atypical carcinoids appeared genetically heterogeneous: One case had no aberrations, and three cases had few aberrations; two of them showed a deletion of 11q. SCLC and LCNEC were characterized by many gains and losses, especially similar changes of 3p, 5q, 5p, and 13q. Although ATC resemble LCNEC morphologically, there were no similarities at the genetic level. We have found a reciprocal relationship of prognosis and the amount of aberrations. TCs and ATCs with few chromosomal changes have the best prognosis, whereas SCLCs and LCNECs were generally characterized by a great amount of aberrations and worst prognosis. There was no unbalanced aberration common in all types of neuroendocrine tumors of the lung.  相似文献   
119.
An actin-depolymerizing marine natural product, mycalolide B, and a related compound, kabiramide D, were labeled with biocytin, a biotin derivative, and used to specify target molecules in cultured rat 3Y1 fibroblasts. Mycalolide B exhibited the ability to bind to various intracellular proteins, probably through the Michael addition of a sulfhydryl group to C5 of mycalolide B. However, no intracellular proteins other than actin apparently reacted with biocytinylated kabiramide D, demonstrating that the binding of kabiramide D to actin was highly specific. Cells treated with biocytinylated kabiramide D followed by staining with fluorescein isothiocyanate-conjugated avidin showed that biocytinylated kabiramide D bound to stress fibers composed of F-actin, although the staining intensity was weaker than the fluorescent phalloidin staining. The assay for the binding of kabiramide D to actin, which had previously been treated with other actin-depolymerizing agents, showed that the actin-binding site for kabiramide D was the same as that for bistheonellide A, but not those for latrunculin A and cytochalasin D.  相似文献   
120.
The efficacy of an early and late treatment with the angiotensin converting enzyme inhibitor lisinopril or the angiotensin II receptor blocker ICI D8731 was investigated in uninephrectomized spontaneously hypertensive rats (SHR). Rats that underwent uninephrectomy (UNX) at six weeks of age were randomly assigned to receive no treatment, lisinopril shortly after UNX, lisinopril starting 16 weeks after UNX, ICI D8731 shortly after UNX, and ICI D8731 starting 16 weeks after UNX. Blood pressure was normalized with both treatments. After six months inulin clearance was not significant different, while proteinuria and prevalence of interstitial fibrosis were significantly reduced in all treatment groups. Immunohistochemical studies revealed an interstitial, periglomerular and perivascular increase of extracellular matrix proteins in all rats, but a markedly reduced expression of collagen I, IV and fibronectin after early and late treatment compared to untreated controls. We found a significant reduction of infiltrating macrophages and T-lymphocytes in all treated animals compared to untreated controls after 2, 4 and 6 months. Especially early treatment was associated with lower numbers of infiltrating cells. Both treatments reduced proliferation of tubular and interstitial cells. There were no striking differences with regard to nephroprotection between the ACE inhibitor and angiotensin II receptor blocker. These findings show that both treatments have beneficial effects on kidney structure and function. They suggest that both ACE inhibition and angiotensin II blockade decrease renal cell proliferation and suppress the infiltration of mononuclear cells that may trigger expression of extracellular matrix proteins and progressive nephrosclerosis.  相似文献   
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