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991.
PURPOSE: We determined the need and sequence of retroperitoneal lymph node dissection and thoracotomy in patients with nonseminomatous testicular cancer, and with residual retroperitoneal and pulmonary masses after chemotherapy. MATERIALS AND METHODS: We studied 159 patients undergoing retroperitoneal lymph node dissection and a thoracotomy following cisplatin based induction chemotherapy for metastatic testicular nonseminomatous germ cell tumor. Several well-known predictors for residual histology (necrosis, mature teratoma and cancer) were evaluated. RESULTS: As expected, necrosis was found more often at retroperitoneal lymph node dissection if the primary tumor was negative for teratoma, the residual mass was small or the decrease in size was great. Contrary, neither residual mass size nor the decrease in size was predictive of the histological status of the residual lung lesion. Histological findings in the retroperitoneum and lung were strongly correlated, such that necrosis at retroperitoneal lymph node dissection was associated with an 89% probability of necrosis in the lung. CONCLUSIONS: Retroperitoneal lymph node dissection should be performed before thoracotomy is considered, since the histological status at dissection is a strong predictor of that at thoracotomy.  相似文献   
992.
OBJECTIVE: To investigate the effect of cataract extraction on the results of automated perimetry in persons with glaucomatous visual field loss. SUBJECTS: Subjects from a retrospective study of visual field progression who underwent cataract extraction during follow-up were identified. Subjects came from the glaucoma service of a hospital-based tertiary referral center. METHODS: Subjects had at least 7 Humphrey 24-2 or 30-2 visual fields over 5 years or more, with an abnormal glaucoma hemifield test result on the first 2 examinations. Visual field data were transferred to a microcomputer and comparison of the visual fields immediately before and after cataract extraction was performed. RESULTS: Sixty-five eyes of 50 subjects (mean age, 71.8 years) were included in the analysis. A mean improvement in mean deviation (MD) of 1.68 dB (P<.001), and a mean worsening in corrected pattern SD (CPSD) of 0.54 dB (P=.09) was observed. The mean unweighted change in threshold in the 52 points of program 24-2 was 1.58 dB, corresponding to a 43.9% increase in sensitivity. A significant correlation between improvement in visual acuity and improvement in MD was also found. A mean increase in CPSD of 1.61 dB (P=.005) occurred in subjects with dense scotomas (minimum threshold value < or = 5 dB) and preoperative CPSD of 8 dB or less. CONCLUSIONS: In persons with glaucomatous visual field defects, cataract extraction produces only a modest improvement in MD. After cataract surgery, the CPSD index worsened in many subjects with dense scotomas. This suggests that the development of cataract can mask progressive glaucomatous visual field loss in such persons.  相似文献   
993.
Role of renin-angiotensin system in hypertension induced by cadmium chloride (CdCl2) in rats has been investigated. Intravenous administration of CdCl (1 mg/kg) produced a biphasic response i.e. a transient fall followed by a marked and consistent rise in blood pressure. The peak hypertensive effect was accompanied by raised PRA levels. Pretreatment with captopril (1 mg/kg, i.v.) losartan (1 mg/kg, i.v.) or captopril + losartan attenuated the pressor response to Cd by 62%, 42% and 100% respectively in separate groups. Central administration of Cd (10 micrograms/rat, i.c.v.) showed a biphasic response similar to that observed after i.v. route. However, it was not accompanied by raised PRA levels. Prior treatment with losartan (10 micrograms/rat, i.c.v.) completely abolished the pressor response to Cd (i.c.v.) whereas it was not affected significantly by captopril (10 micrograms/rat, i.c.v.). On the other hand, centrally administered losartan only partially reduced the pressor response to i.v. Cd. The results are discussed in light of a differential involvement of central vs peripheral renin-angiotensin system in the hypertensive effect of Cd.  相似文献   
994.
The effect of NMDA receptor antagonist phencyclidine (PCP) on expression of cyclooxygenase (COX)-2 mRNA in the rat brain was studied. Administration of PCP (12.5, 25 or 50 mg/kg, i.p., 6 h) caused marked induction of COX-2 mRNA and heat shock gene hsp-70 mRNA, a marker of neuronal injury, in the retrosplenial cortex, in a dose-dependent manner. These results suggest that COX-2 may play a role in the neurotoxicity of NMDA receptor antagonists.  相似文献   
995.
Apnoea, bradycardia and hypotension were elicited by right atrial injections of capsaicin in anaesthetized monkeys. At the threshold dose (2.5 +/- 0.3 microgram/kg), tachypnoea was elicited (latency 1.6 +/- 0.2 s) which got replaced by apnoea with higher doses of capsaicin. These responses persisted (1) after cooling the cervical vagi to 6-8 degrees C, and (2) after instilling xylocaine into the pericardial sac. Tachypnoea and apnoea were elicited after bilateral cervical vagotomy also, but only with higher doses and after a longer latency (5.0 +/- 0.3 s). Right atrial injection of capsaicin and insufflation of halothane stimulated vagal pulmonary C-fibre receptors with a latency of 1.7 +/- 0.7 s and 0.2 +/- 0.1 s, respectively. Tachypnoea/apnoea, bradycardia and hypotension were elicited by left atrial injection of capsaicin also (threshold dose: 5.0 +/- 1.2 micrograms/kg). The respiratory responses persisted (1) after instilling xylocaine into the pericardial sac, and (2) after bilateral cervical vagotomy suggesting that they were due to stimulation of non-cardiac receptors with sympathetic afferents. It is concluded that the initial respiratory responses elicited by right atrial injection of capsaicin were due to stimulation of pulmonary C-fibre receptors with vagal afferents.  相似文献   
996.
997.
This study in Senegal compared the feeding preferences of Anopheles gambiae and A. arabiensis while controlling for equal accessibility to hosts located outdoors under bed net traps. All fed A. gambiae complex females were identified with the aid of the polymerase chain reaction and their blood meal sources were identified by enzyme-linked immunosorbent assay. A total of 605 anophelines, including 281 A. gambiae and 301 A. arabiensis, were captured, 32.2% in the human-baited traps and 67.8% in bovine-baited traps. 30.3% of A. gambiae fed in the former and 69.7% fed in the latter; the corresponding figures for A. arabiensis were 29.6% and 70.4%. Thus, when the hosts were located outdoors and made equally available, the feeding preferences of A. gambiae and A. arabiensis were similar (P = 0.81). These results suggest that biases existed in previous studies, most of which suggested that A. arabiensis was more zoophilic than A. gambiae. Alternatively, the feeding behaviour of these 2 species may differ in various parts of Africa.  相似文献   
998.
999.
The permeation of hairless mouse skin and human cadaver skin by narcotic analgesics was investigated to determine the interspecies variation. Permeability coefficients of morphine, fentanyl, and sufentanil across full-thickness hairless mouse skin were 1 order of magnitude higher than those found for human epidermis. The permeability coefficient of morphine for stripped hairless mouse skin was 500-fold higher than that for intact skin, showing the stratum corneum to be the principal barrier to its penetration. The permeability coefficient of fentanyl for stripped hairless mouse skin was also raised, but stripping caused an inappreciable increase in the permeation rate of sufentanil. The thick dermis of excised mouse skin obviously offered a significant resistance to the permeation of these lipophilic compounds. In comparison, the permeability coefficients of fentanyl and sufentanil through stripped cadaver epidermis (n > or = 25) were 67 and 37 higher than for intact human epidermis, respectively. The skin metabolism of the narcotics was investigated. No significant metabolic degradation of morphine, fentnayl, and sufentanil was observed in either fresh human cadaver skin or hairless mouse skin homogenates in the presence of NADPH cofactor, suggesting a low monooxygenase enzyme presence in skin. Moreover, no measurable glucuronidation of morphine took place in human skin or hairless mouse skin. Both processes proceeded rapidly in liver homogenates (mouse) under identical circumstances. It thus appears that these drugs pass through in intact form.  相似文献   
1000.
Plasma low density lipoprotein (LDL) cholesterol, non-high density lipoprotein (HDL) cholesterol, and apolipoprotein (apo) B, the major protein constituent of LDL, were measured in 1,533 men (mean age 49 +/- 10 years) and 1,597 women (mean age 49 +/- 10 years) participating in the 3rd examination cycle of the Framingham Offspring Study. Mean plasma levels of LDL cholesterol and apoB were higher in men than in women (136 versus 132 mg/dl, P < 0.0001; and 109 versus 95 mg/dl, P < 0.0001, respectively). Increased age was associated with higher plasma LDL cholesterol and apoB levels, especially in women. After adjustment for age and body mass index, LDL cholesterol and apoB levels were still significantly higher in postmenopausal than in premenopausal women, indicating a hormonal effect on LDL metabolism. The associations between coronary heart disease (CHD) and LDL cholesterol, non-HDL cholesterol, apoB, and other plasma lipid and lipoprotein parameters were examined by dividing participants in four groups, based on approximate quartiles for these parameters. Elevated LDL cholesterol levels were not significantly associated with CHD in men, but were in women. This result, at variance with that of several longitudinal studies, is likely due to the cross-sectional design of our analysis. Elevated non-HDL cholesterol and apoB levels were significantly associated with the presence of CHD, in both males and females. A plasma apoB value > or = 125 mg/dl may be associated with an increased risk for CHD. Low plasma levels of HDL cholesterol were also significantly associated with CHD. Plasma triglyceride levels, age and body mass index were strong determinants of LDL cholesterol, non-HDL cholesterol, and apoB levels in men and women. In women, postmenopausal status and elevated blood pressure were also significantly associated with elevated levels of these parameters.  相似文献   
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