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451.
Peculiarities of localisation of total population of hypothalamic neurons, associated with innervation of vagosolitary complex "stomach" area were studied using retrograde axonal transport of horseradish peroxidase. The enzyme was administered in microportions into the mentioned area of vagosolitary complex (100-150 ml of 20% enzyme solution). The labelled neurons were exposed in the hypothalamic area basically from ipsilateral side. Greatest part of these neurons was located within paraventricular nucleus and lateral hypothalamic area as two bands oriented in caudodorsal direction. These bands length varied widely in different animals (ranging from 0.5 to 0.2 mm) mainly due to their disperse caudal ends. Rostral part of these formations were more compact and were joined by a thin cross arch, consisting of bipolar labelled neurons along it. As for interaural line this arch was located in the distance within 6.75-07.05 mm in different animals.  相似文献   
452.
PURPOSE: Neointima formation after arterial injury is inhibited by increased blood flow. The object of this study was to determine whether nitric oxide mediates the effect of increased blood flow on neointima formation. METHOD: Balloon catheter-denuded rat carotid arteries were exposed to increased blood flow or control blood flow by ligation of the contralateral carotid artery. Beginning 2 days before balloon denudation, rats were given either saline vehicle alone or the nitric oxide synthase inhibitor N-nitro-L-arginine-methyl ester (L-NAME) at a dose of 10 mg/kg/day or 2 mg/kg/day intraperitoneally. The normalized neointima area was measured 14 days after denudation. RESULTS: Blood flow was significantly increased by ligation of the contralateral carotid artery for all drug treatments (p<0.008). In rats given saline vehicle only, normalized neointima area was significantly reduced after increased blood flow compared with control blood flow (0.33+/-0.04 compared with 0.48+/-0.03; p=0.006). Systolic blood pressure was significantly elevated by treatment with high-dose L-NAME (p=0.002 compared with vehicle), but was not altered by low-dose L-NAME (p=NS compared with vehicle). Normalized neointima area was not significantly reduced after increased carotid blood flow for rats treated with either dose of L-NAME (p=NS). CONCLUSION: The inhibition of neointima formation by increased blood flow was abolished with hypertensive and nonhypertensive doses of the nitric oxide synthase inhibitor L-NAME, which suggests that the L-NAME effects are independent of systemic hemodynamic alterations. It is concluded that flow-induced inhibition of neointima formation is mediated in part by nitric oxide.  相似文献   
453.
454.
BACKGROUND: Hearts harvested from non-heart-beating donors sustain severe injury during procurement and implantation, mandating interventions to preserve their function. We tested the hypothesis that limiting oxygen delivery during initial reperfusion of such hearts would reduce free-radical injury. METHODS: Rabbits sustained hypoxic arrest after ventilatory withdrawal, followed by 20 minutes of in vivo ischemia. Hearts were excised and reperfused with blood under conditions of high arterial oxygen tension (PaO2) (approximately 400 mm Hg), low PaO2 (approximately 60 to 70 mm Hg), high pressure (80 mm Hg), and low pressure (40 mm Hg), with or without free-radical scavenger infusion. Non-heart-beating donor groups were defined by the initial reperfusion conditions: high PaO2/ high pressure (n = 8), low PaO2/high pressure (n = 7), high PaO2/low pressure (n = 8), low PaO2/low pressure (n = 7), and high PaO2/high pressure/free-radical scavenger infusion (n = 7). RESULTS: After 45 minutes of reperfusion, low PaO2/ high pressure and high PaO2/low pressure had a significantly higher left ventricular developed pressure (63.6 +/- 5.6 and 63.1 +/- 5.6 mm Hg, respectively) than high PaO2/high pressure (40.9 +/- 4.5 mm Hg; p < 0.0000001 versus both). However, high PaO2/high pressure/free-radical scavenger infusion displayed only a trend toward improved ventricular recovery compared with high PaO2/ high pressure. CONCLUSIONS: Initially reperfusing nonbeating cardiac grafts at low PaO2 or low pressure improves recovery, but may involve mechanisms other than decreased free-radical injury.  相似文献   
455.
We present a 63-year old female with mediastinitis following an esophageal perforation, possibly favoured by an oesophageal motility-disorder and the use of non-steroidal anti-inflammatory drugs, who developed a broncho-mediastinal fistula in the left main bronchus. She was successfully treated with intravenous antibiotics, a cervical oesophagostomy and secondary isoperistaltic coloplasty.  相似文献   
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