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991.
Data were collected from 14 older, rural African American men and women to explore how individual motivation affects the initiation and maintenance of health-related behavior. The research consisted of an inductive exploration designed to examine the validity and cultural relevance of an existing theoretical framework for wellness motivation in health behavior change. Through the technique of constant comparative analysis, the basic social process of empowering potential was substantiated as a process of individual growth and goal-directed behavior that facilitated the initiation and maintenance of positive health patterns. The process of empowering potential consisted of three stages: appraising readiness, changing, and integrating change. Two categories provided a cultural context for the process: health value orientation and network affiliation. The data validated and expanded a developing theoretical framework for wellness motivation in health behavior change.  相似文献   
992.
In these studies we examined the temporal effects of intracerebroventricular (i.c.v.) infusions of norepinephrine (NE) on plasma LH and on LHRH mRNA levels in the organum vasculosum of the lamina terminalis (OVLT) and in neurons located in the rostral (r), middle (m) and caudal (c) preoptic areas (POA) of ovariectomized, estrogen-treated rats. Thereafter, we compared these responses to those which occur in androgen-sterilized rats (ASR). NE infusions not only increased plasma LH concentrations but within 1 h after NE, LHRH mRNA levels also were increased significantly in the OVLT and rPOA but not in the mPOA or cPOA. By 4 h, these message levels still were elevated in the OVLT and rPOA and they now also were significantly higher than control values in the mPOA and cPOA. While NE also increased LH secretion in ASR, the plasma LH concentrations obtained were markedly blunted compared to control values. Moreover, NE infusions did not alter single cell levels of LHRH mRNA in any region of the rostral hypothalamus. Previously, we have reported that morphine (s.c.) markedly amplifies NE-induced LH release and questioned whether these responses are accompanied by concomitant augmented increases in LHRH mRNA levels. Morphine alone did not affect basal LHRH mRNA or plasma LH levels. However, when rats were pretreated with morphine (-15 min) and NE was infused i.c.v. at 0 time, significant amplification of LH release occurred but, unexpectedly, morphine completely blocked NE-induced increases in LHRH mRNA levels in all of the neurons we examined. Morphine also amplified LH release in ASR but these responses were significantly less than those obtained in control rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
993.
OBJECTIVE: Our purpose was to determine the acute-phase central hemodynamic and respiratory effects of raw, filtered, filtered and boiled, and meconium-containing amniotic fluid. STUDY DESIGN: Pregnant goats (Capra hircus) in the last one third of pregnancy were given freshly collected autologous amniotic fluid in a volume of 2.5 ml/kg of body weight. Observations were then made at 10, 30, 60, 120, and 180 minutes after amniotic fluid embolism. Pulmonary artery catheters and femoral artery lung water catheters were placed for specimen and data collection. RESULTS: Marked pressor responses were observed in both the pulmonary and systemic circulations with all amniotic fluid infusions. The pressor response was similar with raw, filtered, and filtered and boiled amniotic fluid. The pressor response seen with amniotic fluid containing meconium was significantly greater than that seen with the other forms. No significant effects were observed on cardiac or respiratory function except in the meconium group, where transient left ventricular dysfunction was accompanied by an acute increase in extravascular lung water and dysoxia. CONCLUSIONS: The Capra hircus model is appropriate for the further study of amniotic fluid embolism. The acute pressor effects are transient and involve both the systemic and pulmonary circulations. Left ventricular dysfunction and dysoxia were observed only with embolism of amniotic fluid containing meconium.  相似文献   
994.
995.
BACKGROUND: [corrected] A National Institutes of Health-funded clinical trial of patients undergoing coronary artery bypass randomized perfusate and myocardial preservation to cold, tepid, or warm temperatures. The goal of the trial was to evaluate neurologic function before and after operation (4 days and 1 month after operation) and to measure hematologic data for fibrinolytic potential. METHODS: The three groups comprised 116 patients who completed neurologic evaluation by means of the Mathew scale out of 130 entered into the trial (37 cold group, 50 tepid, and 43 warm). Twenty-five patients had complete hematologic studies done. All three groups were comparable before operation. The myocardial preservation protocol used blood cardioplegic solution at cold (8 degrees to 10 degrees C), tepid (32 degrees C), or warm (37 degrees C) temperature and the systemic perfusate temperature during cardiopulmonary bypass was 20 degrees (cold), 32 degrees C (tepid), or 37 degrees (warm). RESULTS: Patients in the cold group had a longer duration of intubation and postoperative hospitalization and a slightly but significantly higher peak postoperative creatine kinase MB level than patients in the warm group. There were no deaths. There was deterioration in Mathew scale findings in all three groups, and no distinction could be made between groups. However, a significantly higher number in the cold group had an abnormal postoperative neurologic examination result that prompted computed tomographic scanning (18.9% cold, 2% tepid, 9.3% warm). A cerebrovascular accident was documented by computed tomographic scanning in 8.1%, 0%, and 4.7% of patients in the cold, tepid, and warm groups, respectively (not significant). Hematologic data documented significantly increased fibrinolytic potential in the warm group. CONCLUSIONS: Perfusion temperature is a factor in recovery from cardiopulmonary bypass. Cold has more adverse neurologic sequelae that prompt computed tomographic scanning whereas warm has more activation of fibrinolytic potential. Tepid is the best temperature for optimizing recovery from cardiopulmonary bypass.  相似文献   
996.
This report describes an 11-year-old male who presented to his pediatrician at the Bowman Gray School of Medicine in Winston-Salem, N.C., because of long standing enuresis. During evaluation and the following two-week period, this patient was found to have extreme thrombocytosis ranging from 2,175 x 10(9)/L to 3,700 x 10(9)/L. In the absence of any apparent reactive cause, a presumptive diagnosis of essential thrombocythemia was made. Although chemotherapy was considered, the patient was temporarily lost to follow-up before there was a final decision about therapy. One year later, this patient's platelet count had spontaneously decreased to normal (273 x 10(9)/L), and has remained normal during a follow-up period of seven years, although only sporadic platelet counts have been obtained. His most recent physical examination revealed no abnormalities. The case is presented as further evidence that extremely high platelet counts are not necessarily dangerous and do not all require therapy.  相似文献   
997.
998.
Single doses of oral and intravenous furosemide were given to 8 healthy male volunteers (40 mg) and 11 patients with renal failure maintained on continuous ambulatory peritoneal dialysis (CAPD) (80 mg). In the volunteers, absorption was variable. Only one half of the intravenous dose and one third of the oral dose was available for renal pharmacological action as judged by the urinary recovery. In the patients, absorption was also variable and was markedly delayed (tmax 128 vs 90 min) but more complete (bioavailability 70.1 vs 53.6%). The differences between the two groups were not significant, however (95% C.I.: -90 to 30 and -40.4 to 7.5 respectively). The mean elimination half-life was significantly longer in the patients following both the oral (228 vs 65.1 min) and intravenous dose (195 vs 60.3 min). The total body clearance of furosemide in the volunteers was 138 ml x min(-1) and this was much lower in the CAPD patients (61.9 ml x min(-1)) in whom the renal clearance was negligible. Although there were trends indicating differences in absorption between the two groups, the significant differences in furosemide disposition observed in CAPD patients were due to renal failure.  相似文献   
999.
Women who received Norplant contraceptive implants from any of fifteen clinical settings in southeast Texas, U.S.A., were followed for one year to determine their reactions to the method. Of 1,385 who enrolled to receive Norplant implants, 1,253 had implants inserted. Side effects were reported by 78% of those receiving implants and 70% described changes in bleeding patterns. Spotting or irregular bleeding, weight gain and headaches were the conditions reported most frequently. Nine pregnancies were reported during the study period. Six of these, however, existed before the implants were inserted. At the one year anniversary, 143 of women receiving implants had had them removed. Those who discontinued method use were less satisfied, reported more side effects and were more likely to have planned to have another child, thus using the method for spacing, or to have had a change in their marital status while they were using the contraceptive. Providers should counsel patients to focus attention on plans for the future in selecting their contraceptive method. In addition, we recommend, as does the product's distributor, that providers confirm that patients are not pregnant prior to inserting implants.  相似文献   
1000.
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