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71.
Keiko Yamamura Tsunehisa Sakurai Kohji Yano Takashi Osada Toshitaka Nabeshima 《Microbiology and immunology》1995,39(11):895-896
To examine the efficacy of sisomicin (SISO) incorporated into fibrin glue (FG) for the prevention of graft infection in animal models, the susceptibility to infection of Dacron grafts (control) and SISO-FG Dacron grafts following the inoculation of Staphylococcus aureus or S. epidermidis was compared. The results showed that SISO-FG Dacron grafts displayed resistance to graft infection. 相似文献
72.
Shigeki Nagao Yoshihiro Kawabata Takashige Nishikawa Haruhiko Takada 《Microbiology and immunology》1995,39(12):1011-1014
Guinea pigs immunized with Freund's complete adjuvant received challenge injection of the purified protein derivative of Mycobacterium tuberculosis in the flanks and the corneas to prepare delayed-type hypersensitivity (DTH) reactions. The animals were injected subcutaneously with lipopolysaccharide (LPS) or a synthetic lipid A (LA-15-PP). At the skin site primed with DTH reaction, increased swelling and hemorrhagic reaction followed by a definite necrotic reaction occurred. Severe corneal reactions were also observed in the animals. These findings indicate that bacterial endotoxin modulates DTH reactions and induces severe inflammatory reactions. 相似文献
73.
Katsuhiko Yoshimatsu Taketomo Fujiwara Yoshihiro Fukumori 《Archives of microbiology》1995,163(6):400-406
Cytochrome c-550 was purified from Magnetospirillum magnetotacticum to an electrophoretically homogeneous state, and some of its properties were determined. The cytochrome showed absorption peaks at 528 and 409 nm in the oxidized form, and at 550, 521, and 414 nm in the reduced form. Its midpoint redox potential at pH 7.0 was determined to be +289 mV. The primary structure of cytochrome c-550 was determined. Cytochrome c is composed of 97 amino acid residues, and its molecular weight was calculated to be 10,873, including heme c. Its primary structure is very similar to those of Rhodospirillum fulvum and Rhodospirillum molischianum cytochromes c
2, suggesting that M. magnetotacticum is phylogenetically related to photosynthetic bacteria. 相似文献
74.
Hideki Iwata Shunji Tomatsu Seiji Fukuda Atsushi Uchiyama G. M. M. Rezvi Tatsuya Ogawa Toshinori Hori Yoshihiro Nakashima Atsushi Yamagishi Kazuko Sukegawa Nobuyuki Shimozawa Yasuyuki Suzuki Naomi Kondo Tadao Orii 《Human genetics》1995,95(3):257-264
Seven different restriction fragment length polymorphisms (RFLPs) at the N-acetylgalactosamine-6-sulfate sulfatase (GALNS) locus were analyzed using Southern blotting and polymerase chain reaction based techniques to search for the frequency of each RFLP produced by StyI, SphI, HaeIII, StuI, HapII, XhoI, and BamHI restriction endonucleases, respectively, in 36 mutant alleles, including two sibling cases and 100 normal alleles. Calculation of heterozygosity indexes showed that these RFLPs were polymorphic, ranging from 0.31 to 0.69 in mucopolysaccharidosis IVA (MPS IVA) patients compared with 0.21 to 0.65 in normal individuals. There was some significant difference in several RFLPs and in the combination with four kinds of RFLPs (SphI, StuI, HapII, XhoI polymorphisms). The normal alleles were composed of 13 different RFLPs haplotypes; the most common among the Japanese population carrying normal alleles was haplotype 8 (bDEF1) (31.3%), the others being dispersed. The same haplotype 8 was the most frequent in the mutant alleles (44.4%), with seven further haplotypes. These findings revealed the striking variety of polymorphic haplotypes in the MPS IVA gene. By using these five kinds of RFLPs, we examined the theoretical informativity of haplotype analysis in heterozygote detection in nine unrelated MPS IVA families and ten unrelated normal families. All the members of the MPS IVA families studied were diagnosed as a patient, carrier, or noncarrier. We propose that prenatal diagnosis or family analysis in cases in which mutations have not been characterized is now feasible. 相似文献
75.
Optimal strategy of plant antiherbivore defense: Implications for apparency and resource-availability theories 总被引:3,自引:0,他引:3
Plants produce chemicals as methods against animal herbivory. Such chemical defenses are classified into two major categories:
(i) quantitative defenses with massive production of indigestible substances; and (ii) qualitative defenses with production
of poisonous substances. A mathematical model was developed that identified factors that favored the evolution of quantitative
defenses. Selecting an annual plant for simplicity, the allocation of photosynthetic production between growth substances
and defense substances was considered. If the plant invests more in defense substances, it can protect itself more efficiently
from herbivory but with a reduced growth rate. If it invests more in growth substances, the contrary holds. Using Pontoryagin's
maximum principle, the following results were obtained: (i) the plant should conduct quantitative defenses when the growth
rate (G), reflecting resource-availability, is low and the growth period (T) is long as well; (ii) if the plant invests in quantitative defenses, the optimal proportion of defense substances (χ*) should be higher asG is smaller, but it is independent ofT; and (iii) the value of χ* is not monotone for the effectiveness of defense substance (A), but has a maximum at an intermediate value ofA. Predictions of the model partly supported both Feeny's apparency theory, claiming that apparent plants or their parts for
herbivores should quantitatively defend themselves, and Coley's resource-availability theory, claiming that plants with rich
resources should invest in growth rather than defense. 相似文献
76.
Takashi Ueda Yoshihiro Kohli Yoshimichi Abe Takuji Katoh Takeshi Ogasawara Yoshiaki Nojyo Kei Kashima 《Histochemistry and cell biology》1995,103(1):11-17
We evaluated the conditions of fixation for ultrastructurally demonstrating the endogenous peroxidase (PO) activity of macrophages in biopsied human liver. The application of microwaving and immersion fixation with tannic acid and aldehydes allowed excellent visualization of PO activity in the nuclear envelope (NE), rough endoplasmic reticulum (rER), and cytoplasmic granules (CG), with good preservation of cellular ultrastructures. The macrophages with PO activity showed one of the following five patterns of PO localization: positive in both the NE and rER but negative in the CG (type 1); negative in both the NE and rER but positive in the CG (type 2); negative in the NE but positive in both the rER and CG (type 3); positive in all three (type 4); PO negative (type 5). The type 1 cells resembled typical Kupffer cells, type 2 cells monocytes, and type 3 and 4 cells the exudate-resident macrophages considered to be a transitional form between exudate and resident macrophages. Type 5 cells may also be a transitional form between the exudate and resident macrophage, or an end-stage macrophage derived from exudate macrophages which have lost their PO activity. Tannic-acid-aldehyde immersion fixation with microwaving may be a useful method in the study of the PO activities of macrophages in biopsied human liver specimens. 相似文献
77.
Y Kobayashi T Ogihara Y Yamamura F Watanabe T Kiguchi I Ninomiya Y Kumahara 《Endocrinologia japonica》1984,31(1):49-53
Recent reports on the isolation and identification of 19-nor-deoxycorticosterone from the urine of rats with adrenal regeneration hypertension give rise to the possibility of a role of this steroid in the pathogenesis of low renin essential hypertension. The present study was undertaken to investigate the presence of 19-nor-deoxycorticosterone in normal rat serum both by a sensitive enzyme immunoassay and by gas chromatography-mass spectrometry (GC/MS). 19-Nor-deoxycorticosterone in rat serum was separated from other steroids prior to enzyme immunoassay by using high performance liquid chromatography (HPLC). The average concentration of 19-nor-deoxycorticosterone in normal rat serum was 137 +/- 62 ng/dl (mean +/- SD, n = 32). Pooled normal rat serum (50 ml) was purified by HPLC and the purified sample was acetylated with acetic anhydride for GC/MS measurement. The retention time and m/z ions (358, 285, and 257) on the resulting mass fragmentogram coincided in position with those of authentic 21-acetoxy-19-nor-deoxycorticosterone and acetylated normal rat serum extract. The combined characteristics of HPLC elution, antigen-antibody reaction, GC retention and selected ion responses provided strongly evidence supporting the presence of 19-nor-deoxycorticosterone in normal rat serum. 相似文献
78.
Selective elimination of chromosomally unbalanced zygotes at the two-cell stage in the Chinese hamster 总被引:2,自引:0,他引:2
The gametic and zygotic selection of genome imbalance was investigated in the Chinese hamster by direct chromosome analyses of spermatocytes and preimplantation embryos from crosses between chromosomally normal females and males heterozygous for a reciprocal translocation, T(2;10)3Idr, abbreviated here as T3. The karyotypes and the frequencies of embryos observed at the first cleavage in the cross +/+female X T3/+male were consistent with those expected from MII scoring in male T3 heterozygotes. Therefore, it was concluded that there was neither gametic selection against genome imbalance nor zygotic selection from fertilization until the first cleavage metaphase. However, 9.1-10.8% of embryos were arrested at the two-cell stage, and karyotypes of these embryos were confirmed as 22(2,10,10,10(2)), 21(2,10,10), and 21(2,10,10(2)). The common abnormality of these embryos was partial monosomy of chromosome 2. Among day 4 embryos, some chromosomally unbalanced embryos, mainly with a deficiency of other segments of chromosomes 2 and 10, had fewer blastomeres than chromosomally balanced embryos. This finding suggests that cleavage of these embryos had been retarded by day 4 of gestation. 相似文献
79.
Carbonic anhydrase (CA) activity was detected in homogenatesfrom Anabaena variabilis ATCC 29413, M-2 and M-3, but not inthe suspension of the intact cells. Activity was higher in cellsgrown in ordinary air (low-CO2 cells) than in those grown inair enriched with 24% CO2 (high-CO2 cells). Fractionationby centrifugation indicated that the CA from A. variabilis ATCC29413 is soluble, whereas both soluble and insoluble forms existin A. variabilis M-2 and M-3. The addition of dithiothreitoland Mg2 $ greatly decreased the CA activity of A. variabilisATCC 29413. The specific activity of the CA from A. variabilis ATCC 29413was increased ca. 200 times by purification with ammonium sulfate,DEAE-Sephadex A-50 and Sephadex G-100. Major and minor CA peaksin Sephadex G-100 chromatography showed respective molecularweights of 48,000 and 25,000. The molecular weight of the CAdetermined by polyacrylamide disc gel electrophoresis was 42,000?5,000.The activity of CA was inhibited by ethoxyzolamide (I50=2.8?10-9M), acetazolamide (I50=2.5?10-7 M) and sulfanilamide (I50=2.9?10-6M). (Received January 5, 1984; Accepted April 26, 1984) 相似文献
80.
Yasuo Yamamura 《Journal of plant research》1984,97(2):179-191
The growth and matter production were examined forReineckia carnea, an evergreen herb growing on the forest floor in a warm-temperate region. Seasonal change in the biomass of plants growing
in the field was estimated from the harvested sample plants. Carbohydrate contents and respiration rates were measured for
analysis of dry matter economy. Light intensity and temperature on the forest floor were periodically measured.
In mid-spring the biomass reached a maximum which was about half again its minimum value, found in autumn. Two phases, the
productive phase in cooler seasons and the developmental phase in warmer seasons, were distinguished from the annual growth
pattern of this plant. In cooler seasons, positive net production was found without any morphological changes, resulting in
active accumulation of reserves which were mainly soluble sugars. This high net production seems to be closely related to
the favorable light conditions and low respiratory losses. In warmer seasons, though new organs were developed, net production
remained low or was even negative. The morphological development of this plant in these seasons depended mostly on reserves
previously accumulated. This characteristic feature of annual matter economy is considered to be common to evergreen plants
on the forest floor in warm regions. 相似文献