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51.
Helodermin-like and salmon calcitonin (sCT)-like immunoreactivities co-existed in a subset of human calcitonin (hCT)-containing cells in normal human thyroid tissue and medullary thyroid carcinomas. Helodermin/sCT-immunoreactive cells were mostly different from calcitonin gene-related peptide (CGRP)-positive cells. Helodermin and sCT immunoreactivities were not identified in pulmonary and pancreatic hCT-positive neuroendocrine tumors, except for a few lung tumor cells showing positive staining with one of two sCT antisera used. Helodermin immunoreactivity demonstrated by rabbit antiserum R0086 was completely abolished in the presence of synthetic sCT, while sCT immunoreactivity was not absorbed by synthetic helodermin. The carboxyl terminal Arg30-Thr31 sequence (and Pro35 amide structure) of helodermin would be the epitopic site recognized by this antiserum, since a similar amino acid sequence is present in sCT molecules but absent from hCT and CGRP. 相似文献
52.
Callus was induced from juice vesicles of satsuma mandarin on Murashige & Skoog medium supplemented with -naphthaleneacetic acid (NAA), kinetin (K) and gibberellin (GA). Adventitious embryoids arose from the callus tissue on the medium containing 1 mgl–1 NAA alone. The embryoids grew into embryos which resulted in a plantlet on medium containing 1 mgl–1 GA.Abbreviations GA
gibberellin
- K
kinetin
- NAA
-naphthaleneacetic acid 相似文献
53.
The carrageenan-producing red algaKappaphycus alvarezii (Doty) Doty was brought to Vietnam from Japan in 1993. Branch fragments of this species were cultivated in a pond, lagoon, inlet and offshore in Vietnam for the first time. The best daily growth rate (DGR) of plants grown in the lagoon area attained 9–11 % day–1 in May to June (cold season). The water temperature and salinity in this area ranged from 27.2–32.4 °C and 31.4–33.7 °C, respectively. DGR of plants grown in the inlet ranged from 7 to 9% day–1 in June. Grazing by fish has been observed to occur in this area. The DGR of plants grown in the pond ranged from 5–6% in January–July, but decreased to less than 4% day–1 in August (hot season).
K. alvarezii in Vietnam showed a carrageenan yield of 18.8–24.6% and gel strength of 1566–1712 g cm–2. These values are similar ones obtained fromK. alvarezii cultivated in the Philippines and Indonesia. 相似文献
54.
55.
Haruo Takeshita Toshihiro Yasuda Daita Nadano Reiko Iida Masao Nakanaga Etsuko Tenjo Kazumi Sawazaki Koichiro Kishi 《Human genetics》1994,94(3):224-230
The main isozyme patterns of desialylated blood plasma or serum -l-fucosidase (FUCA) were found to be almost identical to those of semen, urine, placental extracts, and leukocyte lysates, when detected by polyacrylamide gel isoelectric focusing, and activity staining using the fluorogenic substrate 4-methylumbelliferyl--l-fucopyranoside. Three phenotypes (1, 2-1, and 2) determined from plasma samples were identical to the phenotypes from urine and leukocyte lysates from the same individuals. A population study of plasma samples collected from 485 Japanese individuals indicated that the frequencies of the FUCA11
* and FUCA12
* alleles were 0.7505 and 0.2495, respectively. The mean plasma enzyme activities (+SD) of the three phenotypes were 318.8 ± 116.7 nmol/ml per h for type 1, 268.0 ± 108.3 nmol/ml per h for type 2-1, and 233.2 ± 84.4 nmol/ml per h for type 2. The mean activities of types 1 and 2 suggest that, on average, the FUCA11
* gene product in plasma has about 1.4 times the activity of FUCA12
*. 相似文献
56.
Possible Involvement of Abscisic Acid in Increases in Activities of Two Vacuolar H+-Pumps in Barley Roots under Aluminum Stress 总被引:1,自引:0,他引:1
Kasai Minobu; Sasaki Masao; Tanakamaru Shigemi; Yamamoto Yoko; Matsumoto Hideaki 《Plant & cell physiology》1993,34(8):1335-1338
Levels of abscisic acid (ABA) in barley roots increased upontreatment with AlCl3. Treatment with AlCl3 or ABA increasedboth ATP-dependent and PPi-dependent H+-pumping activities intonoplast-enriched membrane vesicles. Increase in the H+-pumpingactivities caused by aluminum stress could result from increasedlevels of ABA.
1Present address: Department of Botany, Faculty of Science,Hirosaki University, Hirosaki, Aomori, 036 Japan 相似文献
57.
Seibu Mochizuki Shingo Seki Masa-aki Ejima Tatsuyuki Onodera Masayuki Taniguchi Shin-ichiro Ishikawa 《Molecular and cellular biochemistry》1993,119(1-2):151-157
The roles of the Na+/H+ exchange system in the development and cessation of reperfusion induced ventricular arrhythmias were studied in the isolated perfused rat heart. The hearts were perfused in the working heart mode with modified Krebs Henseleit bicarbonate (KHB) buffer and whole heart ischemia was induced by a one-way ball valve with 330 beat/min pacing. Ischemia was continued for 15 min followed by 20 min of aerobic reperfusion (control). Amiloride (1.0mM), an inhibitor of the Na+/H+ exchange system, was added to the KHB buffer only during reperfusion (group B) or only during ischemic periods (group C). Electrocardiographic and hemodynamic parameters were monitored throughout the perfusion. Coronary effluent was collected through pulmonary artery cannulation and PO2, PCO2, HCO
3
–
and pH were measured by blood-gas analyzer.The incidence of reperfusion induced ventricular arrhythmias was 100%, 100% and 0% in control, group B and group C, respectively. The mean onset time of termination of reperfusion arrhythmias was significantly shorter in group B than in control. PCO2 increased from 39.0±0.9 to 89.3±6.0 mmHg at the end of ischemia in control and from 40.6±0.4 to 60.5±5.8 in group C, the difference between groups was statistically significant. HCO
3
–
level decreased from 21.8±0.1 to 18.3±0.5 mmol/l in control, however, this decrease was significantly inhibited in group C (from 22.0±0.5 to 20.3±0.2). The increase in PCO2 and the decrease in HCO
3
–
in group B were similar over time to those observed in control. The decrease in pH produced by ischemia was marked in control (from 7.35±0.01 to 6.92±0.04) and group B (from 7.34±0.01 to 6.94±0.02), whereas a decrease in pH was significantly prevented in group C (from 7.34±0.01 to 7.15±0.04). There were no significant differences in PCO2, HCO
3
–
or pH among the three groups during reperfusion.These experiments provide evidence that amiloride significantly prevented the incidence of reperfusion arrhythmias when added only during ischemia and significantly terminated reperfusion arrhythmias when added only during reperfusion. Amiloride may prevent a decrease in pH, due to alterations in PCO2 and/or HCO
3
–
. These changes in PCO2 and HCO
3
–
might be indirectly influenced by inhibition of the Na+/H+ exchange system via Cl–/HCO
3
–
exchange. The mechanism by which amiloride terminates reperfusion arrhythmias seems to involve electrophysiological effects which were not directly addressed in this experiment. 相似文献
58.
Norio Tada Takuya Sakamoto Akihiko Kagami Keiko Mochizuki Kosei Kurosaka 《Molecular and cellular biochemistry》1993,119(1-2):171-178
Human plasmain vitro inhibits the growth of coagulase negative staphylococci,S. epidermidis, which may be pathogenic in the immunocompromised host. To determine the antimicrobial components, serum was fractionated by column chromatography, which revealed that elution areas where lipoproteins can be yielded had high antimicrobial activity againstS. epidermidis. Therefore, lipoprotein fractions, including very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL), were separated by ultracentrifugation and incubated withS. epidermidis. All 3 lipoprotein fractions suppressed bacterial growth within the first 3 h but VLDL enhanced bacterial growth after 9 h of incubation compared with the control. HDL, however, inhibited bacterial growth throughout 21 h of incubation.To confirm these results, serum from healthy volunteers was separated by ion exchange column chromatography and again by HPLC to purify the antimicrobial fraction. In the protein analysis with gradient polyacrylamide-SDS gel, apolipoprotein Al (apo Al), which is a major apolipoprotein of HDL, was detected in the antimicrobial fraction. Therefore, this fraction was loaded onto an immunoaffinity column coupled with the anti-apo Al monoclonal antibody (Mab). Unbound fraction had no antimicrobial activity, but anti-S. epidermidis activity was recovered from the bound fraction which consisted mainly of apo Al, All and apo C in protein composition.These results indicated that the antimicrobial activity was associated with the apo Al-containing lipoprotein particles (HDL). This property of HDL may directly affect bacterial growth and promote the self-defense mechanisms of normal and immunocompromised individuals. 相似文献
59.
Takayoshi Yoshida Koji Yamamoto Masao Udo 《European journal of applied physiology and occupational physiology》1993,66(2):155-160
The purpose of the present study was to assess the relationship between the rapidity of increased gas exchange (i.e. oxygen uptake
) and increased cardiac output (
) during the transient phase following the onset of exercise. Five healthy male subjects performed multiple rest-exercise or light exercise (25 W)-exercise transitions on an electrically braked ergometer at exercise intensities of 50, 75, or 100 W for 6 min, respectively. Each transition was performed at least eight times for each load in random order. The
was obtained by a breath-by-breath method, and
was measured by an impedance method during normal breathing, using an ensemble average. On transitions from rest to exercise,
rapidly increased during phase I with time constants of 6.8–7.3 s. The
also showed a similar rapid increment with time constants of 6.0–6.8 s with an apparent increase in stroke volume (SV). In this phase I,
increased to about 29.7%–34.1% of the steady-state value and
increased to about 58.3%–87.0%. Thereafter, some 20 s after the onset of exercise a mono-exponential increase to steady-state occurred both in
and
with time constants of 26.7–32.3 and 23.7–34.4 s, respectively. The insignificant difference between
and
time constants in phase I and the abrupt increase in both
and SV at the onset of exercise from rest provided further evidence for a cardiodynamic contribution to
following the onset of exercise from rest. 相似文献
60.
Toshitsugu Nakamura Masao Hotchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):11-16
DNA strand breaks (nicks) in non-parenchymal cells (NPCs) in CCl4-induced acute or chronic liver injury in rats were detected using an in situ nick translation method; their dynamic changes
were analysed in relation to the proliferation pattern of hepatocytes and NPCs, as revealed by bromodeoxyuridine (BrdU)-up-take.
In acute injury, hepatocyte proliferation started before centrilobular necrosis had occurred, whereas BrdU-labeled sinusoidal
NPCs markedly increased only after centrilobular necrosis was apparent. DNA breakages in NPCs paralleled the proliferation
pattern of these cells, suggesting that nicks are physiological, and reflect proliferation and activated gene expression.
In chronic injury, liver cirrhosis developed after 9 weeks, but BrdU-labeling of hepatocytes was almost the same level as
that in untreated liver. The number of BrdU-labeled NPCs showed only a slight increase, while those with DNA breakages were
much more frequent in the cirrhotic stage, suggesting a significant role for NPCs in the fibrotic process. These results indicate
that DNA strand breaks in NPCs act as a marker for activation states such as proliferation, differentiation and/or activated
gene expression. 相似文献