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11.
Cell proliferation in the prostate complex of the castrate mouse   总被引:1,自引:0,他引:1  
Cell proliferation during 100 h of continuous androgen challenge was studied in the seminal vesicle and coagulating gland of Balb/c mice castrated 3 days or 14 days prior to the first daily injection of 250 mug testosterone propionate. Continuous labelling with [3H] thymidine indicated that the seminal vesicle was almost totally responsive to androgen, as early as 3 days after castration, whereas the androgen sensitivity of the coagulating gland increased from 30% at 3 days after castration to 85% at 14 days after castration. In both tissues the magnitude of the proliferative reaction could be related to the extent of cell loss prior to stimulation. The duration of the pre-replicative phase in the response of the seminal vesicle to androgen was 20-25 h both at 3 and 14 days after castration. In the coagulating gland the pre-replicative phase was 40 h at 3 days after castration and 20 h at 14 days after castration. The maximum uptake of [7alpha-3H] testosterone administered to mice 3 days after castration was significantly greater (P less than 0-01) in the seminal vesicle compared to the coagulating gland. At 14 days the seminal vesicle and coagulating gland exhibited a similar capacity for uptake. The in vivo metabolism of [7alpha-3H] testosterone was studied by thin layer chromatography 30 min and 120 min after administration. A high proportion of the radioactivity extracted from all the tissues was associated with highly polar steroids. At 3 days after castration, the seminal vesicle, 2 h after administration of radioactive testosterone, retained a much higher proportion of radioactivity associated with dihydrotestosterone than did the coagulating gland. The localization of steroid in mice 3 days after castration was studied by dry-mount autoradiography at intervals up to 2 h after the injection of [1,2,6,7(n)-3H]-testosterone. A heavier deposition of silver grains was observed over autoradiographs of the seminal vesicle. In the seminal vesicle the grains were primarily located over nuclear areas whereas in the coagulating gland the grains were diffusely distributed over both nuclear areas and over cytoplasmic areas.  相似文献   
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The authors review recent and current literature on the relationship between psychological factors and cancer. They discuss the roles of predisposing personality patterns and emotional stress in the development, site, and course of cancer; the influence of awareness of terminal illness on the behavior of cancer patients; and the management of psychiatric symptoms in these patients.  相似文献   
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Cell-mediated immunity (CMI) to homologous spermatozoal antigens was studied in sixty-two males following vasectomy of a duration of 1-10 years. A group of twenty-two normal, fertile non-vasectomized males was also included in the study. The inhibition in the leucocyte migration test (LMT), in the presence of spermatozoal antigen, was taken as an index of CMI. Twenty of the sixty-two vasectomized males (32.2 percent) showed a positive LMT reaction. When the results were analysed with reference to the duration of vasectomy, it was noted that four cases each (22.2 percent), showed a positive LMT reaction in the groups 0-2 years, and 3.5 years. On the other hand twelve cases gave a positive reaction in the group 6-10 years (46.1 percent). It appears that the incidence of CMI to spermatozoa increases with the duration in vasectomy.  相似文献   
15.
Vascular input impedance and associated hydraulic power was measured in rabbit isolated lungs. The study was focused on changes in impedance and in pulsatile hydraulic power during relaxation and contraction of vascular smooth muscle. Pulsatile power was found to be at a minimum when smooth muscle tone was such that the pulmonary arterial pressure was in the physiological range, and increased both when the vessels were relaxed and further constricted. Input impedance was found to be determined mainly by the large, proximal ('extra-alveolar') arteries.  相似文献   
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Intrauterine fetal demise is a source of anxiety to both patient and physician. Heretofore, the standard treatment was either careful observation until the patient went into labor or attempt at induction of labor with oxytocin. Unfortunately, oxytocin stimulation has not proven to be uniformly successful for this problem. Prostaglandin E2 suppositories have been shown to be effective in inducing uterine evacuation after intrauterine fetal demise. In the opinion of the authors, this approach will in the future replace the sometimes dangerous and emotionally laden convention of watchful delayed therapy.  相似文献   
18.
Conscious sheep with permanent indwelling cannulae in the lateral ventricles and the cisterna magna were Na depleted and then perfused for 9 h with an artificial CSF solution. There were 3 experimental groups: Group I (n=5) received perfusion with aritifical CSF containing NA 170 MEq./1, Group II (n=7) received perfusion with artificial CSF containing Na 145 mEq./1, Group III (n=7) received no perfusion. In Group I the blood aldosterone level fell from 26.4 +/- 7.4 to 8.6 +/- 2.3 ng/100 ml by 9 h after perfusion. There was no significant change in plasma [Na] or [K], blood angiotensin II or plasma renin concentration. Blood cortisol and corticosterone levels rose. There was also a fall in post-perfusion. Group III showed no significant change in blood aldosterone concentration. Multivariate statistical analysis showed that the fall in aldosterone levels during 170 mEq./l Na perfusion could not be accounted for by changes, either alone or together, of ACTH as evidenced by alteration in blood cortisol or corticosterone, or by change of plasma [Na], [K] or renin concentrations. This data supports the hypothesis of an additional factor which may be of CNS origin being involved in the control of aldosterone secretion.  相似文献   
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Seven obese and five normal weight patients were studied before, during and after one hour of methoxyflurane-nitrous oxide anaesthesia during peripheral surgical operations and compared with eight patients of normal weight anaesthetized with nitrous oxide-meperidine and d-tubocurare. Estimates were made of renal function, including serum and urinary electrolytes, osmolarity, uric acid, urea and creatinine. Renal clearances for the latter three substances were also calculated. Serum and urinary inorganic and organic fluoride concentrations were measured, as were renal clearances. This low dose methoxyflurane anaesthesia resulted only in a decrease in uric acid clearance among all the measures, when compared to the meperidine-nitrous oxide controls. The clearance of uric acid remained depressed for longer in the obese patients, but otherwise they did not differ from the normal weight patients. It is possible but not proven that depressed uric acid clearance may be related to the organic fluoride metabolite and an early indicator of methoxyflurane renal toxicity. The previously documented biotransformation of methoxyflurane was seen in this study. A double peak in serum inorganic fluoride was shown in all patients but one. Rather large differences in peak levels of serum inorganic fluoride occurred. The only significant difference between the obese and normal weight patients as far as fluoride metabolism was concerned was a greater variability in the serum inorganic fluoride levels in the obese patients. It would appear that the obese patient metabolizes methoxyflurane in a quantitatively if not qualitatively different fashion than the normal weight patient, perhaps because of fatty infiltration of the liver. Caution is advised in the use of methoxyflurane for more than 90 minutes of low concentration administration in view of the unpredictability of the biotransformation.  相似文献   
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