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91.
Zymosan-induced and luminol-aided chemiluminescence (CL) of whole blood from beagle dogs was estimated for the function of polymorphonuclear leucocytes (PMNs). Whole blood (0.1 ml) was examined directly and results were obtained within 20 min. A phagocytic function of PMNs can be estimated from the peak CL counts and the number of PMNs in a specimen, and the opsonic activity can also be estimated by the peak time showing peak CL after the addition of non-opsonized zymosan. The optimal temperatures to keep diluted whole blood for the CL measurement was around 13 degrees C. Thus, this method offers information concerning the functions of phagocytic cells in whole blood.  相似文献   
92.
Spleen cells from Toxoplasma lysate antigen (TLA)-sensitized BALB/c mice showed the strong cytotoxic activity against both natural killer (NK)-sensitive cells (YAC-1 and RL male-1) and NK-insensitive cells (P-815), when incubated with TLA or recombinant human IL-2 (rhIL-2). The increment of TLA concentration in culture medium increased the cytotoxic activity. Treatment of effector cells; spleen cells from TLA-sensitized mice incubated with TLA, with anti-asialo GM1 or anti-Thy-1 plus complement inhibited the cytotoxic activity of effector cells, whereas treatment with anti-mouse Lyt-2.2 serum plus complement had no effect on the cytotoxic activity. Treatment of spleen cells from TLA-sensitized mice with anti-asialo GM1 and/or anti-Thy-1 plus complement inhibited cytotoxic activities of effector cells. These results suggested that spleen cells sensitized with TLA both in vivo and in vitro were asialo GM1 positive and Thy-1 positive, and the majority of cytotoxic cells induced by TLA were similar to lymphokine-activated killer (LAK) cells induced by IL-2.  相似文献   
93.
94.
Root length of Holcus lanatus L. declined rapidly with increasing lead and zinc concentrations in nutrient solution. In all used Pb and Zn concentrations root growth of genotypes coming from a Pb-Zn mine area, was greater than that of the control, suggesting that these genotypes evolved tolerance to Pb and Zn.
Negative correlation was also observed between chlorophyll content and increased heavy metal concentrations. The greater chlorophyll content found in tolerant genotypes, in different Pb and Zn concentrations, in comparison with the control, could be served to distinguish tolerant and non-tolerant genotypes.  相似文献   
95.
Osteolytic defects were detected radiographically in the distal sesamoid bone of a 16-month-old Bralers heifer, in the middle phalanx of a 14-month-old American Gray Brahman bull, and in the distal phalanx of a 3-year-old American Gray Brahman bull. The articular cartilage was damaged in each animal because of osteolysis or pathologic fracture. After each animal was anesthetized and positioned in lateral recumbency, the lesions were curetted and packed with cancellous bone harvested from the same animal's tuber coxae. Basic postoperative management involved stall rest and immobilization of the graft site with a fiberglass cast (42 to 79 days), after which a support bandage was used for approximately 2 weeks. Recurrence of lameness has not been observed in these animals for 60 months, 58 months, and 21 months, respectively. These cases exemplify the benefit of using an autogenous cancellous bone graft for treatment of severe osteolysis of a digit in cattle.  相似文献   
96.
Two mungbean varieties, Guj-1 and PIMS-1 differing in their productivity potential, were examined to investigate their photosynthetic system at various stages of growth in relation to yield with two different dates of sowing. Vertical leaves were found to be beneficial. On the other hand, excessive leaf area during the later stages of growth may be detrimental to yield. Lower LAD at seedling stage and overall high NAR values may be reflected in higher grain yield. NAR declined as season progressed and this, in turn, may be related with increase in LAI. The grain yield was considerably more at the first date of sowing as compared to second date of sowing, the effect was being more pronounced in var. PIMS-1 . Various environmental factors recorded at two different dates of sowing and at various stages of growth indicated that these factors may have influenced the yield potential at two different dates of sowing.  相似文献   
97.
Chloroform-methanol (2:1 v/v), absolute methanol, and 90% acetone were evaluated for their effectiveness as extractants of chlorophyll a from samples of phytoplankton communities collected from catfish ponds. Chloroform-methanol consistently extracted more chlorophyll a than either 90% acetone or methanol. Precision for the methanol extraction was also unacceptably low, with an average coefficient of variation of 17%. Average coefficients of variation for the chloroform-methanol and 90% acetone extraction procedures were 6 and 5%, respectively. Filtered samples should be steeped in chloroform-methanol for at least 4 h to obtain maximum chlorophyll extraction, and the addition of MgCO3 to the extractant as a buffer is not necessary.  相似文献   
98.
The response time to cimaterol (CIM), a beta-adrenergic agonist, by broiler chickens for carcass characteristics, muscle composition, muscle fiber size, catheptic enzyme activity, and tenderness was determined. Two trials were conducted in which chickens were fed a control diet (CON) containing 0 ppm of CIM or a diet containing 1 ppm of CIM. Trial 1 consisted of 55, 31-d-old broiler chickens individually fed for up to 48 h. At 0, 6, 12, 18, 24, and 48 h, five CON and five CIM-fed chickens were killed. Trial 2 consisted of 160, 33-d-old broiler chickens group-fed for up to 14 d. At 2, 4, 6, 8, 10, 12, and 14 d, 10 CON and 10 CIM-fed chickens were killed. The breast muscle (BM) and leg muscle (LM) weight, cathepsin B and L activities, DNA, RNA, and protein concentration, and BM shear force value (SFV) were measured in both trials. Thigh muscle (TM) SFV were measured in Trial 2 only. Fiber size of BM was measured (five birds per treatment) at d 2, 6, 10, and 14. In Trial 1, BM weight and SFV were lower in CIM-fed birds at 6 h (P less than .05). In Trial 2 BM SFV were higher at d 8 (P = .06) and d 10 (P less than .05) in CIM-fed chickens. The SFV of CIM-fed chickens were higher at d 4, 8, 10, 12, and 14 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
99.
In an experiment of 36 days duration 46 one-day-old chicks were divided into 5 groups and fed with different concentrations of vitamin D3. The animals of the group which lacked vitamin D3, showed the typical rachitic lesions. After a 15 days lack of vitamin D3 the chicks of another group were treated with standard food (2000 I.U. vitamin D3/kg food) with the consequence of an approximation of the analyzed parameters to those of the control group within 3 weeks. When fed with 60,000 I.U. of vitamin D3 after a 15 days lack of this vitamin, the animals showed an over-hasty healing process, ending up with signs of intoxication which were even more conspicuous when fed with 120,000 I.U. of vitamin D3. Besides an increasing calcification of osteoblasts and endothelial cell membranes as well as a degeneration of osteoblasts, a clear increase of eosinophilic granulocytes could be noticed. In all groups free erythrocytes within the ground substance were found. There was no evidence of necroses of osteocytes or of bone.  相似文献   
100.
The amount of β‐endorphin‐like immunoreactivity (β‐END‐LI) in porcine corpora lutea from several stages of the oestrous cycle and the effects of progesterone, oxytocin, and prolactin on β‐END‐LI secretion in vitro by luteal cells were studied. Porcine corpora lutea obtained on days 1–5, 6–10, 11–13, 14–18, and 19–21 of the cycle were used to prepare extracts for β‐END‐LI determination. Additionally, corpora lutea from days 11–13 and 14–18 were enzymatically dissociated and isolated luteal cells were used for further study of β‐endorphin secretion in vitro. Cells were cultured in serum‐free defined M 199 medium (106 cells/ml) at 37°C under 5% CO2 in air, for 12 h. The influences of the following factors on β‐END‐LI secretion by luteal cells were tested: progesterone (10–9, 10–7 and 10–5M ), oxytocin (0.01, 0.1, 1 and 10 ng/ml), and prolactin (0.1, 1, 10 and 100 ng/ml). The β‐END‐LI contents in extracts and media were measured by radioimmunoassay. The tissue concentration of β‐END‐LI was lowest on days 1–5 of the cycle (0.35 ± 0.03 ng/g wet tissue). Subsequently, it constantly increased to the highest value on days 14–18 (16.58 ± 0.52 ng/g wet tissue) and on days 19–21 it declined (11.10 ± 0.52 ng/g wet tissue). Progesterone at a low dose (10–9 M ) resulted in significant (p < 0.05) increases and decreases in β‐END‐LI secretion by luteal cells from days 11–13 and 14–18, respectively. Higher doses of progesterone (10–7 and 10–5 M ) had no effect on β‐END‐LI release, compared with the control group. All dose‐levels of oxytocin used decreased β‐END‐LI secretion by luteal cells on days 11–13 and 14–18 of the cycle. Prolactin at doses of 0.1 and 1 ng/ml on days 11–13, and all doses tested on days 14–18 resulted in decreases in β‐END‐LI release from luteal cells. These results document evident changes in β‐END‐LI content in the pig corpus luteum during its development and indicate the potential roles of progesterone, oxytocin, and prolactin in luteal cell secretion of β‐END‐LI.  相似文献   
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