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991.
The method of polar coordinate mapping of lesions on the aortic wall around orifices was used to study the effect of unilateral nephrectomy on sudanophilic lesions in rabbits. Four groups of six rabbits each were studied. Group I had a right nephrectomy with a short renal artery stump. Group II had a sham right nephrectomy. Group III had a left nephrectomy with a short renal artery stump and Group IV a sham left nephrectomy. All groups were allowed to recover for one week and were then fed rabbit chow enriched with 2% cholesterol and 6% corn oil for a four-week period. Groups I and III showed a marked alteration in lesions around the stump with both proximal and distal peaks. Group I also showed the development of skewing of the left renal lesion to the left, presumably because of a change in aortic flow due to removal of the proximal right renal flow. The right renal artery had a lesion skewed to the right; this was not altered by left nephrectomy and was probably due to coeliac flow. The data provides strong evidence that sudanophilic lesions in rabbit aortas are altered by local flow disturbances. 相似文献
992.
K van Besien KA Sobocinski PA Rowlings SC Murphy JO Armitage MR Bishop OK Chaekal RP Gale JP Klein HM Lazarus PL McCarthy JM Raemaekers J Reiffers GL Phillips AV Schattenberg LF Verdonck JM Vose MM Horowitz 《Canadian Metallurgical Quarterly》1998,92(5):1832-1836
Advanced low-grade lymphomas are usually incurable with conventional-dose chemotherapy. It is uncertain whether cures are possible with high-dose therapy and bone marrow transplant from a human leukocyte antigen (HLA)-identical sibling. We sought to determine the outcome of HLA-identical sibling bone marrow transplants in advanced low-grade lymphoma in an observational study of 113 patients conducted at 50 centers participating in the International Bone Marrow Transplant Registry (IBMTR). The median patient age was 38 years (range, 15 to 61). Eighty percent had stage IV disease at the time of transplantation. The median number of prior chemotherapy regimens was two (range, 0 to 5). Thirty-eight percent had refractory disease and 29% a Karnofsky performance score (KPS) less than 80%. All patients underwent allogeneic bone marrow transplantation from a HLA-identical sibling donor. The conditioning regimen included total-body irradiation (TBI) in 82% of patients; cyclosporine was used for graft-versus-host disease prophylaxis in 74%. Survival, disease-free survival, recurrence rate, treatment-related mortality, and causes of death were determined. Three-year probabilities of recurrence, survival, and disease-free survival were 16% (95% confidence interval [CI], 9% to 27%), 49% (95% CI, 39% to 60%), and 49% (95% CI, 39% to 59%), respectively. Higher survival was associated with pretransplant KPS >/=90%, chemotherapy-sensitive disease, use of a TBI-containing conditioning regimen, and age less than 40 years. We conclude that high-dose therapy followed by transplantation from a HLA-identical sibling leads to prolonged survival in some patients with advanced low-grade lymphoma. Most mortality is treatment-related, and recurrences are rare. 相似文献
993.
E Rogers S Teahan H Gallagher MR Butler R Grainger TE McDermott JA Thornhill 《Canadian Metallurgical Quarterly》1998,159(3):851-854
PURPOSE: Owing to the risk of future malignancy, many postpubertal male subjects presenting with unilateral cryptorchidism undergo orchiectomy rather than orchiopexy. We examined the incidence of spermatogenesis and carcinogenesis in whole orchiectomy specimens removed from postpubertal cryptorchid male subjects. We review the concept that orchiectomy is justifiable in these patients. MATERIALS AND METHODS: A total of 52 patients with postpubertal cryptorchidism (unilateral in 48, bilateral in 4) were retrospectively analyzed from 1984. Patient age ranged from 15 to 66 years (mean 26). Six patients presented with primary infertility (unilateral in 3, bilateral in 3). The undescended testicles were palpable in 32 cases (62%). All patients underwent unilateral orchiectomy and whole specimens were examined histologically. RESULTS: Histology showed normal spermatogenesis in only 1 orchiectomy specimen, while 15 had maturation arrest, 6 testicular agenesis and 30 seminiferous tubular atrophy and/or Sertoli-cell-only syndrome with no spermatogenesis. The location of the undescended testis was the superficial inguinal pouch in 32 cases, inguinal canal in 6 and inside the deep ring in 8. Absent spermatogenesis was significantly associated with a high level of maldescent and with increasing age. Two patients (4%) had carcinoma in situ of the testicle. Torsion of an undescended testicle occurred in 1 patient (2%). CONCLUSIONS: This analysis of cryptorchid testes in postpubertal male subjects confirms that the majority cannot contribute to fertility, have significant malignant potential and may undergo torsion. Therefore, orchiectomy remains the treatment of choice for the majority of postpubertal male subjects presenting with unilateral cryptorchidism. 相似文献
994.
995.
996.
Previously, we have demonstrated that chronic exposure to immobilization (IMO) did not modify the influence of catecholamines on active behaviour of rats in the holeboard, but clearly increased the role of these amines in the forced swimming test (FST). In the present experiment, it was studied whether or not chronic IMO altered the role of dopamine in the two tests. Adult male Sprague-Dawley rats were left either undisturbed or subjected daily to 2 h of IMO stress for 12 days. On the following day, half of the rats were administered saline and the others the dopamine antagonist haloperidol (0.5 mg/kg). Then the rats remained undisturbed in the animal room (controls) or were subjected to acute IMO for 2 h. Finally, all animals were exposed consecutively to the holeboard (4 min) and the FST (5 min). In non-chronically stressed rats, acute IMO depressed behaviour in the holeboard but not in the FST. In chronic IMO rats the inhibitory effect of acute IMO on holeboard activity was slightly reduced as compared to controls. Acute IMO increased struggling in rats previously exposed to chronic IMO but did not alter struggling in non-chronically stressed rats. Whereas the inhibition caused by haloperidol treatment in the active behaviour of rats in the holeboard was not altered by chronic IMO, the inhibitory effect of haloperidol in the active behaviour of rats in the FST was greater after chronic IMO, particularly in rats also subjected to acute IMO. These data suggest that chronic IMO stress potentiates the role of dopamine in a specific behavioural task such as the FST and adds support to the previously published data demonstrating enhanced behavioural and neurochemical responses to dopamine-related drugs after chronic stress. 相似文献
997.
JW Lowenthal JJ York TE O''Neil RA Steven DG Strom MR Digby 《Canadian Metallurgical Quarterly》1998,63(1-2):191-198
The time course of incorporation of [14C]arachidonic acid and [3H]docosahexaenoic acid into various lipid fractions in placental choriocarcinoma (BeWo) cells was investigated. BeWo cells were found to rapidly incorporate exogenous [14C]arachidonic acid and [3H] docosahexaenoic acid into the total cellular lipid pool. The extent of docosahexaenoic acid esterification was more rapid than for arachidonic acid, although this difference abated with time to leave only a small percentage of the fatty acids in their unesterified form. Furthermore, uptake was found to be saturable. In the cellular lipids these fatty acids were mainly esterified into the phospholipid (PL) and the triacyglycerol (TAG) fractions. Smaller amounts were also detected in the diacylglycerol and cholesterol ester fractions. Almost 60% of the total amount of [3H]Docosahexaenoic acid taken up by the cells was esterified into TAG whereas 37% was in PL fractions. For arachidonic acid the reverse was true, 60% of the total uptake was incorporated into PL fractions whereas less than 35% was in TAG. Marked differences were also found in the distribution of the fatty acids into individual phospholipid classes. The higher incorporation of docosahexaenoic acid and arachidonic acid was found in PC and PE, respectively. The greater cellular uptake of docosahexaenoic acid and its preferential incorporation in TAG suggests that both uptake and transport modes of this fatty acid by the placenta to fetus is different from that of arachidonic acid. 相似文献
998.
999.
G Scalise MR Mazaheri AS Hamblin P Gioannini AJ Zuckerman DC Dumonde 《Canadian Metallurgical Quarterly》1976,22(3):257-260
Although the rise in blood copper is associated with onset of the acute haemolytic crisis of chronic copper poisoning in sheep, the sudden fall in erythrocyte glutathione is apparently not due to a direct action of the copper. Moreover the reduced glutathione of the red cells is converted to some form that is not capable of regeneration by the pentose-phosphate mechanism. Only negligible inhibition of the pentose-phosphate enzymes occurs. As the haemolysis proceeds, there is a rapid recovery of erythrocyte glutathione levels, and a marked increase in pentose-phosphate enzyme activity, consistent with influx of young red cells. It seems that the release of copper into blood from liver at the haemolytic crisis is associated with an increase of the oxidative state of the blood, possibly by simultaneous release of other components from the liver. 相似文献
1000.
Two patients with a clinical picture identical to idiopathic ocular cicatricial pemphigoid had received long-term (six to nine years) echothiophate iodide treatment for control of glaucoma in the affected eyes after cataract extraction. Basement membrane zone staining for IgG was seen in the conjunctiva of one affected eye. Decreased or absent goblet cells, epidermalization of the conjunctiva, fibroses, and abnormal numbers of inflammatory cells were seen in both affected eyes. 相似文献