全文获取类型
收费全文 | 1080篇 |
免费 | 69篇 |
国内免费 | 1篇 |
出版年
2022年 | 8篇 |
2021年 | 11篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 21篇 |
2015年 | 37篇 |
2014年 | 47篇 |
2013年 | 107篇 |
2012年 | 69篇 |
2011年 | 52篇 |
2010年 | 41篇 |
2009年 | 47篇 |
2008年 | 70篇 |
2007年 | 73篇 |
2006年 | 81篇 |
2005年 | 61篇 |
2004年 | 65篇 |
2003年 | 73篇 |
2002年 | 56篇 |
2001年 | 14篇 |
2000年 | 6篇 |
1999年 | 14篇 |
1998年 | 8篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 13篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 11篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 10篇 |
1981年 | 10篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1972年 | 3篇 |
1970年 | 2篇 |
1969年 | 7篇 |
排序方式: 共有1150条查询结果,搜索用时 31 毫秒
1.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
2.
Summary Distribution of molluscan cardio-excitatory tetrapeptide Phe—Met—Arg—Phe—NH2 (FMRFamide) was determined by means of immunohistochemistry in the brain and neurohypophysis of the lamprey, Lampetra japonica. Many FMRFamide-like immunoreactive neurons were found in the periventricular nuclear region and in a region near the mammillary recess. Neurons situated in the former region were larger. The immunoreactive cell groups were shown to be located at sites differing from those of the AF-positive cell groups. The fibers of immunoreactive neurons extended in all directions within the brain and towards the spinal cord, some reaching the third ventricle and capillaries. Thus, FMRFamide-like immunoreactive peptides appear to function as neurotransmitters or neuromodulators and possibly also as neurohormones. FMRFamide-like immunoreactive material was rarely observed in the posterior neurohypophysis (neural lobe), but was noted to be present to a limited extent in the caudal part of the anterior neurohypophysis (median eminence). It would thus follow that FMRFamide-like immunoreactive neurons may not necessarily be related to the hypothalamo-neural lobe system, but may possibly be associated with the hypothalamoadenohypophysial system. The pineal body showed no FMRFamide-like immunoreactivity. 相似文献
3.
Michiko Arita Takeshi Honda Toshio Miwatani Tae Takeda Toshifumi Takao Yasutsugu Shimonishi 《FEMS microbiology letters》1991,79(1):105-110
A heat-stable enterotoxin produced by Vibrio mimicus (VM-ST) was studied. VM-ST was purified from a culture supernatant of V. mimicus strain AQ-0915 by ammonium sulfate fractionation, hydroxyapatite treatment, ethanol extraction, column chromatography on both SP-Sephadex C-50 and DEAE-Sephadex A-25, and HPLC, and the recovery rate was about 15%. Purified VM-ST was heat-stable. VM-ST activity was cross-neutralized by anti-STh antiserum. The amino acid composition of the purified VM-ST was determined 17 amino acid residues in the following sequence: Ile-Asp-Cys-Cys-Glu-Ile-Cys-Cys-Asn-Pro-Ala-Cys-Phe-Gly-Cys-Leu-Asn. This composition and sequence were identical to those of V. cholerae non-O1-ST. These results clearly demonstrate the production of a characteristic VM-ST by V. mimicus. 相似文献
4.
A procedure is described for preparation of highly active (Na+,K+)-ATPase from rat heart which has a specific activity of 200-600 mumol Pi/mg/h. The procedure is simple and can be applied to small amounts of heart muscle (approximately 1 g). The ATPase activity was more than 90% sensitive to ouabain (at concentrations up to 1 mM). The ouabain sensitivity is biphasic with about 20% of the ATPase activity being inhibited at approximately 3 X 10(-7) M ouabain. 相似文献
5.
Y Sugiyama S Taketomi H Tawada K Meguro H Ikeda T Fujita 《Hormones et métabolisme》1988,20(3):145-149
In the perfused pancreas from normal SD rats, AD-4610 (0.01-0.1 mM) potentiated biphasic insulin secretion induced by 7.5 mM of glucose. The concentration-response curve of insulin secretion to glucose was shifted leftwards with AD-4610 (0.1 mM) without altering either the threshold concentration of glucose to induce insulin secretion or the maximal insulin response to glucose, indicating increased sensitivity of the pancreatic B-cells to glucose. On the other hand, AD-4610 was 10-fold less effective in altering insulin secretion induced by arginine and glyceraldehyde. The effect of AD-4610 on insulin secretion and glucose metabolism was compared with that of tolbutamide in vivo. AD-4610 (100 mg/kg) potentiated insulin secretion induced by an intravenous glucose load, and also accelerated glucose metabolism without altering basal insulin secretion in normal rats. On the other hand, tolbutamide (20 mg/kg) increased basal insulin secretion, but slightly decreased glucose-induced insulin secretion. In yellow KK mice with hyperglycemia, AD-4610 (10-100 mg/kg) had a dose-dependent hypoglycemic action, but tolbutamide did not. Thus, AD-4610 stimulated insulin secretion in a glucose-dependent fashion and enhanced glucose metabolism in vivo. These results suggest that AD-4610 selectively potentiates glucose-induced insulin secretion by increasing the sensitivity of pancreatic B-cells to glucose and may be useful for treating human NIDDM through a different mechanism than that of tolbutamide. 相似文献
6.
Nalidixic acid-resistant mutations of the gyrB gene of Escherichia coli 总被引:41,自引:0,他引:41
Jun-ichi Yamagishi Hiroaki Yoshida Michiko Yamayoshi Shinichi Nakamura 《Molecular & general genetics : MGG》1986,204(3):367-373
Summary DNA fragments of 3.4 kb containing the gyrB gene were cloned from Escherichia coli KL-16 and from spontaneous nalidixic acid-resistant mutants. The mutations (nal-24 and nal-31) had been determined to be in the gyrB gene by transduction analysis. Nucleotide sequence analysis of the cloned DNA fragments revealed that nal-24 was a G to A transition at the first base of the 426th codon of the gyrB gene, resulting in an amino acid change from aspartic acid to asparagine, and nal-31 was an A to G transition at the first base of the 447th codon, resulting in an amino acid change from lysine to glutamic acid. This indicates that mutations in the gyrB gene are responsible for nalidixic acid resistance. 相似文献
7.
Effect of the H-meromyosin plus ATP system on F-actin 总被引:4,自引:0,他引:4
8.
Protein Kinases Are Involved in Prolonged Acetylcholine Release from Rat Hippocampus Induced by Thyrotropin-Releasing Hormone Analogue NS-3 总被引:2,自引:0,他引:2
Michiko Oka Yoshinori Itoh Yojiro Ukai Yoshiaki Yoshikuni Kiyoshi Kimura 《Journal of neurochemistry》1996,66(5):1889-1893
Abstract: The effects of various protein kinase inhibitors on acetylcholine release from the rat hippocampus induced by the local application of NS-3 (montirelin hydrate, CG-3703), a thyrotropin-releasing hormone analogue, into the medial septum-diagonal band were examined using in vivo microdialysis. Perfusion of NS-3 (1 µ M ) into the medial septum-diagonal band for 20 min produced a pronounced and prolonged increase in the hippocampal acetylcholine efflux. Pretreatment of the medial septum-diagonal band with either K-252a, a nonselective protein kinase inhibitor, or selective protein kinase A inhibitor H-89 almost completely blocked the acetylcholine efflux evoked by NS-3, and selective protein kinase C inhibitor calphostin C inhibited the action of NS-3. On the other hand, NS-3 (0.1–10 µ M ) or TRH (1–100 µ M ) increased the cyclic AMP efflux from the medial septum-diagonal band in a concentration-dependent manner, as measured by microdialysis. These findings suggest that protein kinases A and C in the neurons of the medial septum-diagonal band are involved in the mechanism of the prolonged stimulation of acetylcholine release from the hippocampus induced by thyrotropin-releasing hormone and its analogue, NS-3. 相似文献
9.
Kenichi Ogasawara Makoto Bannai Naruya Saitou Ryuichi Yabe Kenichi Nakata Michiko Takenaka Kiyoshi Fujisawa Makoto Uchikawa Yoshihide Ishikawa Takeo Juji Katsushi Tokunaga 《Human genetics》1996,97(6):777-783
Polymorphism of the ABO blood group gene was investigated in 262 healthy Japanese donors by a polymerase chain reactions-single-strand conformation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A1 (provisionally called ABO*A101, *A102, *A103 and *A104 according to the guidelines for human gene nomenclature), 3 for B (ABO*B101, *B102 and *B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O203). Nucleotide sequences of the amplified fragments with different SSCP patterns were determined by direct sequencing. Phylogenetic network analysis revealed that these alleles could be classified into three major lineages, *A/*O1, *B and *O2. In Japanese, *A102 and *13101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, *O101 (43%) and *O201 (53%), were observed. These results may be useful for the establishment of ABO genotyping, and these newly described ABO alleles would be advantageous indicators for population studies. 相似文献
10.
We sampled 17 populations of a rare autotetraploid Aster kantoensis (Asteraceae) from three river systems located in central Japan, and studied them for allelic variation at 22 enzyme loci. There was no significant correlation between the actual population size and three genetic diversity parameters, suggesting that the effective population size was very small even for the large populations, i.e., even large populations may still have a high probability of being of recent origin and remain influenced by the founder effect. Compared to other autotetraploid species, the total genetic variation of A. kantoensis is small. The number of alleles and gene diversity of a population were not significantly different among the river systems, although the percentage of polymorphic loci was different. Genetic differentiation among river systems was larger than between populations within the river systems, thereby indicating that gene flow between river systems is small, especially between the Kinu River system and Tama or Sagami River systems. 相似文献