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1.
A few reports have suggested the possibility that feeding conditions might affect the sexual maturation of free-ranging Japanese
monkeys in provisionized troops. In the present study, the sexual maturation of male monkeys at Takasakiyama in 1984, nine
years after the start of restriction of artificial feeding, was examined externally and histologically and the results were
compared with data obtained in 1971, when artificial foods were abundantly given. Spermatogenesis was not observed in any
of the males under 4.5 years old in the present study, whereas it was noted in some premature 3.5-year-old males and in all
males over 4.5 years old in the 1971 study. The age of sexual maturation thus rose by one or more years over the 13-year period
from 1971 to 1984. The lag in sexual maturation of the males at Takasakiyama in 1984 could have been induced by the restriction
of artificial feeding. 相似文献
2.
Kazuhiro Yoshikawa Masao Seto Ryuzo Ueda Yuichi Obata Kunihiro Notake Takashi Yokochi Toshitada Takahashi 《Immunogenetics》1991,33(5-6):352-360
The CD7 molecule is a differentiation antigen found on the surface of T lymphocytes and also on a very minor fraction of acute nonlymphocytic leukemia (ANLL). To study the genomic structure of the CD7 gene, two clones (SY4 and SY22) were isolated by screening a genomic library with a CD7 cDNA probe. Restriction mapping of these two phage clones showed that both overlapped each other, covering a total length of 23 kilobases (kb). Transfection of mouse L cells demonstrated that SY22 contains the gene expressing the CD7 antigen reactive with monoclonal CD7 antibody (Tp40), while SY4 does not. Subcloning of a 10.5 kb fragment from a 14.4 kb insert of SY22 contained the structural gene for the CD7 antigen. Detailed restriction mapping and partial sequence analysis revealed the CD7 gene to consist of four exons. By RNase protection assay, multiple initiation sites — 122 base pairs (bp) to — 38 bp from ATG translation initiation site were demonstrated. The promoter region had high G+C content and contained two SP1 binding sites (CCGCCC) and an AP2 binding site (CCCCAGGC), but lacked CAAT and TATA motifs. 相似文献
3.
An 8-year-old girl with meningococcal meningitis lacked serum complement activity. The seventh component of complement (C7) could not be detected in her serum by either functional or immunochemical analysis. The levels of the other components were within the normal range. Her serum complement activity was restored by the addition of purified C7. Her fresh serum showed a total absence of bactericidal activity against Neisseria meningitidis, group Y, but her serum bactericidal activity was restored by the addition of purified C7. The restoration of her serum bactericidal activity was completely inhibited in the presence of Mg2+ EGTA. These findings suggest that restoration of the bactericidal activity of her serum against N. meningitidis might be mediated by the specific antibody against N. meningitidis and the reconstituted complement system in her serum. Heterozygous deficiency of C7 was found in 10 of her family members. Genetic studies showed that the mode of inheritance might be an autosomal codominant trait. No genetic linkage between deficiency of C7 and the HLA system was found. 相似文献
4.
Molecular and Cellular Biochemistry - 2,3-Bisphosphoglycerate accumulates in mammalian erythrocytes, where it facilitates the supply of oxygen to the tissues by binding to hemoglobin. Regulatory... 相似文献
5.
Copulatory behavior unrelated to conception is sometimes observed in some non-human primates including the Japanese monkey.
In the present study, the authors examined whether a mature follicle or a newly formed fresh corpus luteum was observed in
the ovaries of female Japanese monkeys which displayed the copulatory behavior unrelated to conception.
Post-conception copulatory behaviors were observed in three out of four females usually kept in individual cages in an air-conditioned
room, and in two out of three females without infants kept in an outdoor group cage. However, neither a mature Graafian follicle
nor a fresh corpus luteum formed newly after conception was observed in any of these females by laparoscopic examinations
conducted immediately after termination of the copulatory behavior. In females with infants born in the preceding birth season,
copulatory behaviors were observed in three out of four females kept in the outdoor group cage, and in two out of four females
in a free-ranging troop. Ovulation was confirmed in one case out of the three kept in the outdoor group cage, but neither
a mature follicle nor a newly formed corpus luteum was observed in the remaining four females.
These findings suggest that copulatory behavior in the Japanese monkey is not always controlled by the development of a follicle
or ovulation in the ovary. 相似文献
6.
Frederick J. Griffin Carol A. Vines Murali C. Pillai Ryuzo Yanagimachi Gary N. Cherr 《Development, growth & differentiation》1996,38(2):193-202
Polyclonal antibodies were generated to the 105 kDa herring sperm motility initiation factor (SMIF) and used to explore the role of SMIF in sperm-egg interaction. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting with SMIF antibodies, it was demonstrated that SMIF is present as a minor (4–7% of total chorion protein) component of the chorion. The major polypeptides in the chorion migrated at 117 kDa and in a grouping between 48–54 kDa, with other minor bands above and below. The only detectable glycosylated component was the 105 kDa band, which was resolved at two isoelectric points (8.22 and 8.31) after isoelectric focusing gel electrophoresis. Using antibodies to SMIF, fertilization was blocked, sperm motility was inhibited in vitro in the presence of solubilized SMIF and SMIF binding sites on sperm were localized. Lastly, SMIF was localized to the region of the herring egg that encircles the micropyle. 相似文献
7.
Norio Ohashi Yoko Koyama Hiroshi Urakami Masahiro Fukuhara Akira Tamura Fumihiko Kawamori Seigo Yamamoto Shiro Kasuya Kentaro Yoshimura 《Microbiology and immunology》1996,40(9):627-638
A total of 40 strains of Orientia tsutsugamushi (34 isolates from patients and trombiculid mites in Japan, and 6 prototype strains of antigenic variants) were examined for classification based on the reactivities with type-specific monoclonal antibodies in indirect immunofluorescence tests, and on the restriction fragment length polymorphism of a polymerase chain reaction (PCR)-amplified 56-kilodalton type-specific antigenic protein gene. By these methods, several antigenic and genotypic variants were found among the strains, and these variants were classified into types and further into subtypes. These results suggest that there are many variants in O. tsutsugamushi, and the methods used here seem to be useful for the systematic classification of the numerous variants. A strain which may be a new type distinguishable from those identified previously was also found in this study. Furthermore, variety in the degree of pathogenicity in mice related to type and/or subtype classification were observed. 相似文献
8.
Ryuzo Sakakibara Kazuya Sakai Yuko Sakurai Tae Kohnoura Masatsune Ishiguro 《Molecular reproduction and development》1993,34(1):101-106
Mouse oocyte maturation inhibitory factors, on the basis of inhibitory activity of spontaneous germinal vesicle breakdown (GVBD) of denuded mouse oocytes in culture, were extracted and partially purified by reversed-phase resin adsorption and Sephadex G-100 and G-50 column chromatographies from the urine of pregnant women. Denuded oocytes obtained from ovaries of ICR mice underwent spontaneous GVBD by cultivation for 3 h in modified Krebs–Ringer's buffered solution, while this spontaneous GVBD was found to be inhibited by adding the final preparation (U-D-4) of urine. The inhibition was dose dependent, ranging from 0.6 to 10 μg protein/ml medium. Oocytes treated with U-D-4 and resuspended in control medium resumed GVBD. The molecular mass of U-D-4 was estimated to be less than 2,000 Da with gel filtration. Ether treatment failed to extract inhibitory factor(s) from U-D-4 and pepsin treatment inactivated U-D-4, indicating that inhibitory factor(s) in U-D-4 are peptide-like substances. The inhibitory effect of U-D-4 on spontaneous GVBD was partially reversed in the presence of naloxone, a potent opioid antagonist. U-D-4s obtained from urine samples of pregnant women, nonpregnant women, and men showed the inhibitory effect on spontaneous GVBD; however, the activity of U-D-4 obtained from pregnancy urine was significantly more potent than those of the other urine samples. © 1993 Wiley-Liss, Inc. 相似文献
9.
10.
Transglutaminase catalyzes the intermolecular cross-linking of peptides between Gln and Lys residues, forming an -(-glutamyl) lysine bond. Amyloid -peptide, a major constituent of the deposits in Alzheimer disease, contains Lys16, Lys28, and Gln15 which may act as substrates of transglutaminase. Transglutaminase treatment of amyloid -peptide (1–28) and amyloid -peptide (1–40) yielded cross-linked oligomers. Transglutaminase-treated A retarded neurite extension of PC12 cells, and rat cultured neurons of hippocampus and septum, brain areas severely affected by Alzheimer disease, and subsequently caused cell death, whereas the transglutaminase-untreated counterparts did not show harmful effects. The transglutaminase-catalyzed oligomers of amyloid -peptide and their neurotoxicity may be involved in two characteristics in Alzheimer disease, neuronal degeneration and formation of the insoluble deposits.Abbreviations: AD – Alzheimer disease, A – amyloid -peptide, DMEM – Dulbecco's modified Eagle's medium, DMEM/F–12–1:1 mixture of DMEM and Ham's F–12 medium, FCS – fetal calf serum, HS – horse serum, PAGE – polyacrylamide gel electrophoresis, MTT – 3-(4,5-dimethylthiazol–2-yl)–2,5-diphenyltetrazolium bromide, NGF – nerve growth factor, TGase – transglutaminase. 相似文献