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141.
26 dry specimens of mandible were utilised for making antropometric & condylo coronal angle measurements. 26 living subjects were radiographed in a standardized SMV an CCA values were established. Average value of Antero posterior dimension was obtained to be 8.5 mm and latero medial dimension obtained to be 17 mm. Left and right condylo coronal angle (CCA) from dry specimens was assessed to be 18 & 16 respectively. From the living subjects CCA was established as 17 degrees in Indian population. The following radiological implications are evident from this study. (1) A tomographic cut of the TMJ if done at the depth of 8 to 9 mm i.e. half of 17 mm (lateromedial dimension average) it would pass through the centre of the condyle and may contribute to the diagnostic importance. (2) The CCA of 17 degrees obtained for Indian population may be utilized by clinicans to obtain clearer transpharyngeal and transcranial views of the TMJ by adjusting the radiographic cone to 17 degrees tilt in horizontal angulation keeping the standard values for vertical angulation as--10 degrees for transpharyngeal and +25 degrees for transcranial views. 相似文献
142.
B Chakravarti DN Chakravarti HJ Müller-Eberhard 《Canadian Metallurgical Quarterly》1998,243(2):591-597
There is a wealth of evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) can prevent colorectal cancer. In this article the role of cyclooxygenase 1 and 2, the principle target of NSAIDs, in the development of colorectal cancer is reviewed. Cyclooxygenase is constitutively expressed in normal colonic epithelium and surrounding stroma and could catalyse the generation of malondialdehyde which is a known mutagen and could initiate colorectal carcinogenesis. Mutation of APC which is an early genetic event leads to the expression of cyclooxygenase 2 which may prevents the appropriate apoptosis of mutant adenoma cells. Other proneoplastic effects of cyclooxygenase include changing the action of Transforming Growth Factor beta from anti-proliferative to pro-proliferative, reducing adherence to extracellular matrix, promotes metastasis and angiogenesis. These properties of cyclooxygenases suggest that inhibition of both isoforms may have important protective effects against colorectal cancer. 相似文献
143.
FG Uglov VV Gritsenko DN Do?nikov OIu Mochalov PA Dubika?tis SV Kuznetsov KIu Senchik LS Bodunova 《Canadian Metallurgical Quarterly》1997,156(5):55-60
Complex estimation of the state of the lungs at the postperfusion and early postoperative periods based on roentgenological, clinical data, investigations of the parameters of oxygenation and mechanics of respiration was carried out in 32 children with septal defects of the heart, operated upon under conditions of artificial blood circulation with different kinds of the transfusion maintenance including the apparatus "Cell Saver 5" (CS) for the reinfusion of autoerythrocytes. The dynamics of endotoxicosis, hematological parameters during and after operation and requirements in transfusion media were studied. Differences in these indicators were established between the patients operated upon with the use of donor hemocomponents and those who were operated upon with CS. It allowed a conclusion about the role of the method of intraoperative reinfusion of erythrocytes in substantially less frequency and severity of the postperfusional pulmonary complications in this category of patients. 相似文献
144.
MB Mitchell DN Campbell DR Clarke DA Fullerton FL Grover MM Boucek B Pietra M Luna AL Shroyer JR Coll JW Rosky 《Canadian Metallurgical Quarterly》1998,116(2):242-252
OBJECTIVES: Our objectives were to (1) review our experience with heart transplants in infants (age < 6 months), (2) delineate risk factors for 30-day mortality, and (3) compare outcomes between our early and recent experience. METHODS: Records of all infants listed for transplantation in our center before September 1996 were analyzed. Early and recent comparisons were made between chronologic halves of the accrual period. Univariate analysis was used to analyze potential risk factors for 30-day mortality (categorical variables, Fisher's exact test; continuous variables, nonparametric Wilcoxon rank-sum test). Multivariable analysis included univariate variables with p values < or = 0.10. Actuarial survivals were estimated (Kaplan-Meier) and compared by the log-rank test. RESULTS: Fifty-one of the 60 infants listed for transplantation were operated on (waiting list mortality 15%). Thirty-day mortality was 18% overall, 30% in the first 3 years and 10% in the last 3 years (p = 0.07). Sepsis was the commonest cause of early death (4/9). Univariate analysis suggested four potential risk factors for early death: preoperative mechanical ventilation (p = 0.01), prior sternotomy (p = 0.002), preoperative inotropic drugs (p = 0.08), and warm ischemia time (p = 0.08). Multivariable analysis indicated that prior sternotomy (p = 0.01) was an independent risk factor for 30-day mortality. Actuarial survivals were 80%, 78%, and 70% at 1, 2, and 3 years, and these figures improved between early and recent groups (p = 0.05). Late deaths were most commonly due to acute rejection (3/5). CONCLUSIONS: Results of heart transplantation in infancy improve with experience. Prior sternotomy increases initial risk. Intermediate-term survival for infants with end-stage heart disease is excellent. 相似文献
145.
S Ganguly J Dasgupta AS Das K Biswas DN Mazumder 《Canadian Metallurgical Quarterly》1997,18(3):119-121
Spinal cord injuries are rare in children, in face of their higher mobility comparing to adults. The high cervical and the thoracic segments of the spine are more frequently affected. In the last 10 years we had 90 cases of spinal injuries in our service being 12 with neurologic deficient (8 male and 4 female) and four of them without radiographic abnormality, even in the dynamics studies. The authors emphasise the possibility of occurrence of neurologic deficit in children after trauma, even without any radiographic abnormality. 相似文献
146.
S Komatsu J Panés JM Russell DC Anderson VR Muzykantov M Miyasaka DN Granger 《Canadian Metallurgical Quarterly》1997,29(2):683-689
Recent reports indicate that bacterial endotoxin (lipopolysaccharide) and cytokines elicit a more profound increase in the surface expression of intercellular adhesion molecule-1 (ICAM-1) in cultured endothelial cells derived from spontaneously hypertensive (SHR) versus normotensive Wistar-Kyoto rats (WKY). Our objective in this study was to characterize and compare in vivo ICAM-1 expression in SHR and WKY under basal conditions and after 5 hours of endothelial cell activation with either lipopolysaccharide (5 mg/kg i.p.) or tumor necrosis factor-alpha (TNF-alpha; 1, 5, and 10 micrograms/kg i.p.). ICAM-1 expression was quantified in different tissues by the double-radiolabeled monoclonal antibody technique. When constitutive (baseline) ICAM-1 expression was corrected for endothelial cell surface area, significantly higher values were noted in SHR than WKY but only in splanchnic organs. Lipopolysaccharide and TNF-alpha elicited significant increases in ICAM-1 expression in all tissues of both WKY and SHR. However, the magnitude of the lipopolysaccharide-induced ICAM-1 upregulation in heart, stomach, skeletal muscle, and brain was significantly lower in SHR than WKY. A similar blunted ICAM-1 upregulation was noted in the stomach of SHR after administration of 5 micrograms/kg TNF-alpha. The differences in induced ICAM-1 expression between SHR and WKY do not appear to be due to differences in endothelial cell surface area or plasma glucocorticoid levels. These results suggest that chronic arterial hypertension results in altered ICAM-1 expression on the endothelium, which may contribute to the abnormal inflammatory responses associated with this disease. 相似文献
147.
Corticostriatal connections of auditory areas within the supratemporal plane and in rostral and caudal portions of the superior temporal gyrus were studied by the autoradiographic anterograde tracing technique. The results show that the primary auditory cortex has limited projections to the caudoventral putamen and to the tail of the caudate nucleus. In contrast, the second auditory area within the circular sulcus has connections to the rostral and the caudal putamen and to the body of the caudate nucleus and the tail. The association areas of the superior temporal gyrus collectively have widespread corticostriatal projections characterized by differential topographic distributions. The rostral part of the gyrus projects to ventral portions of the head of the caudate nucleus and of the body and to the tail. In addition, there are connections to rostroventral and caudoventral portions of the putamen. The mid-portion of the gyrus projects to similar striatal regions, but the connections to the head of the caudate nucleus are less extensive. Compared with the rostral and middle parts of the superior temporal gyrus, the caudal portion has little connectivity to the tail of the caudate nucleus. It projects more dorsally within the head and the body and also more dorsally within the caudal putamen. These differential patterns of corticostriatal connectivity are consistent with functional specialization at the cortical level. 相似文献
148.
A combined MR and computational fluid dynamics (CFD) study is made of flow in a simple phantom laboratory flow rig consisting of a 180 degree bend with straight entry and exit sections. The aim was to investigate the potential of the use of MRI-linked CFD simulations for in vivo use. To this end, the experiment was set up for both steady and pulsatile laminar flow conditions, with Reynolds and Dean numbers and Womersley pulsatility parameter representative of resting flow in the human aorta. The geometrical images of the pipe and the velocity images at entry to the bend were used as boundary conditions for CFD simulations of the flow. The CFD results for both steady and pulsatile cases compared favorably with velocity images obtained at exit from the bend. Additional information such as pressure and wall shear stress, which either could not be measured adequately via MRI, or could not be measured at all, was also extracted from the simulation. Overall, the results were sufficiently promising to justify pursuing subsequent in vivo studies. 相似文献
149.
DN Bailey 《Canadian Metallurgical Quarterly》1998,110(4):491-494
The relationship between frequency of intake of different types of fat and breast cancer was investigated in a case-control study conducted in Montevideo, Uruguay, during the time period 1994-1996. Our study comprised 365 cases and 397 controls. A moderate and non-significant increase in risk of breast cancer, associated with total fat intake, was found. Saturated and monounsaturated fat intake were not associated to an increased risk of this malignancy, whereas polyunsaturated fat and linoleic acid were associated with a significantly reduced risk (OR 0.26, 95% CI 0.13-0.53). On the contrary, both alpha-linolenic acid and cholesterol intakes were associated with an increased risk of breast cancer (OR for the upper quartile of intake of alpha-linolenic acid 3.79, 95% CI 1.53-9.40). When alpha-linolenic was examined at different levels of intake, the OR's were significantly higher at low levels of linoleic acid intake (OR 7.5, 95% CI 1.9-28.8). 相似文献
150.
Mortality determinants in massive pediatric burns. An analysis of 103 children with > or = 80% TBSA burns (> or = 70% full-thickness) 总被引:1,自引:0,他引:1
SE Wolf JK Rose MH Desai JP Mileski RE Barrow DN Herndon 《Canadian Metallurgical Quarterly》1997,225(5):554-65; discussion 565-9
OBJECTIVE: Survivors and nonsurvivors among 103 consecutive pediatric patients with massive burns were compared in an effort to define the predictors of mortality in massively burned children. SUMMARY BACKGROUND DATA: Predictors of mortality in burns that are used commonly are age, burn size, and inhalation injury. In the past, burns over 80% of the body surface area that are mostly full-thickness often were considered fatal, especially in children and in the elderly. In the past 15 years, advances in burn treatment have increased rates of survival in those patients treated at specialized burn centers. The purpose of this study was to document the extent of improvement and to define the current predictors of mortality to further focus burn care. METHODS: Beginning in 1982, 103 children ages 6 months to 17 years with burns covering at least 80% of the body surface (70% full-thickness), were treated in the authors' institution by early excision and grafting and have been observed to determine outcome. The authors divided collected independent variables from the time of injury into temporally related groups and analyzed the data sequentially and cumulatively through univariate statistics and through pooled, cross-sectional multivariate logistic regression to determine which variables predict the probability of mortality. RESULTS: The mortality rate for this series of massively burned children was 33%. Lower age, larger burn size, presence of inhalation injury, delayed intravenous access, lower admission hematocrit, lower base deficit on admission, higher serum osmolarity at arrival to the authors' hospital, sepsis, inotropic support requirement, platelet count < 20,000, and ventilator dependency during the hospital course significantly predict increased mortality. CONCLUSIONS: The authors conclude that mortality has decreased in massively burned children to the extent that nearly all patients should be considered as candidates for survival, regardless of age, burn size, presence of inhalation injury, delay in resuscitation, or laboratory values on initial presentation. During the course of hospitalization, the development of sepsis and multiorgan failure is a harbinger of poor outcome, but the authors have encountered futile cases only rarely. The authors found that those patients who are most apt to die are the very young, those with limited donor sites, those who have inhalation injury, those with delays in resuscitation, and those with burn-associated sepsis or multiorgan failure. 相似文献