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971.
Chondroitinase B and chondroitinase C were separated from an extract of Flavobacterium heparinum induced with chondroitin 6-sulfate by using column chromatography on hydroxylapatite. Chondroitinase C was eluted together with the activities of hyaluronidase, delta4,5glycosiduronase, and sulfatase. The latter two activities were eliminated exclusively by passing the crude chondroitinase C fraction through a phosphono-cellulose column pre-equilibrated with 0.07M sodium phosphate buffer (pH 6.8). Chondroitinase C was then purified by affinity chromatography using dermatan sulfate-bound AH-Sepharose 4B coated with the same glycosaminoglycan. Purification of the enzyme was achieved 18-fold and in 73% yield. On the other hand, the activities of delta4,5glycosiduronase and sulfatase were decreased to 50 and 60%, respectively, as compared with those in the crude chondroitinase B fraction, after passing the fraction through a column of phosphono-cellulose pre-equilibrated with 0.1M sodium phosphate buffer (pH 6.8). The remaining activities of these two enzymes were then eliminated from chondroitinase B by affinity chromatography with heparin-bound AH-Sepharose 4B coated with dermatan sulfate. In the affinity chromatography used in the present study, non-covalent coating of the glycosaminoglycan-bound (covalently) AH-Sepharose 4B with the same or another glycosaminoglycan was found to be important. 相似文献
972.
K Kawanishi Y Nishina T Ishida S Machida S Yamamoto T Ofuji N Sakura N Yanaihara 《Hormones et métabolisme》1980,12(12):660-664
C-peptide immunoreactivity (CPR) levels were measured in dog superior pancreaticoduodenal vein using synthetic dog C-peptide and its antiserum. The basal CPR level was approximately twice as high as the basal immunoreactive insulin (IRI) level on a molar basis. Glucose (10 mg/kg/min) or arginine (250 mg/kg/min) infusion for 5 min into the superior pancreaticoduodenal artery caused a prompt, parallel increase in IRI and CPR. IRI and CPR were closely equimolar at peak secretions. One bolus administration of synthetic neurotensin (10 microgram/kg) into the same artery produced a mild hyperglycemic response and biphasic IRI and CPR responses at 30 min in the vein. The IRI and CPR increases were closely equimolar during the first phase of secretion, but during the second peak a larger increase was found in CPR than IRI. Upon infusion of synthetic substance P (50 ng/kg/min) for 30 min, IRI and CPR concentrations showed a parallel and closely equimolar fall. These results indicate that insulin and C-peptide were released from beta cells in equimolar concentrations. 相似文献
973.
Noboru Hara 《Journal of plant research》1980,93(1):1-12
The early ontogeny of theGinkgo leaf was studied by scanning electron microscope. The lamina of the leaf is derived from the protuberance of the adaxial
side of a leaf buttress. The protuberance shows successive bifurcations. The second bifurcation occurs approximately at a
right angle to the first. Thus, the abaxial surface of the leaf is derived from the outer surface of the protuberance and
the adaxial is derived from the depressed inner surface of the protuberance formed by the first and second bifurcations.
It is supposed that thick veins along both edges of the lamina are differentiated by an uneven dichotomous branching system
of procambia caused by positional relationships: both edges of the lamina are derived from the parts of the protuberance just
above a pair of procambia which come from the stem.
On the shoot apex, there are a central cell group, which consists of only a few cells, and radially-arranged cell files. The
leaf primordium is initiated from a sector area which consists of several files among radially-arranged cell files. 相似文献
974.
Noboru Hara 《Journal of plant research》1975,88(2):89-101
The structure of the vegetative shoot apex ofCassiope lycopodioides D. Don, which has a decussate leaf arrangement, was analyzed using trans- and longisections to generate a three-dimensional viewpoint. The apical dome of this species is relatively high from the middle to the maximal area phase of a plastochron. Therefore, the initial protrusion of a pair of leaf primordia occurs laterally on an apical dome conspicuously in contrast to the cases ofDaphne pseudo-mezereum andClethra barbinervis whose apices are nearly flat or slightly convex. The structure of the apex ofCassiope, however, may be understood with the concept of “apical sectors” on the same basis asDaphne andClethra (Hara, 1961, 1962, 1971a, b, c). 相似文献
975.
Treatment with prostaglandin (PG) D2 in concentrations (10−8 to 10−7 M) insufficient to alter the basal tone potentiated the contractile response of helical strips of dog mesenteric arteries to transmural electrical stimulation but did not influence the response to norepinephrine. The potentiating effect of PGD2 was not prevented by treatment with diphloretin phosphate, a PG antagonist, whereas contractions of dog cerebral arteries induced by PGD2 were suppressed. The 3H-overflow evoked by transmural stimulation in superfused mesenteric arterial strips previously soaked in 3H-norepinephrine containing media was significantly increased by PGD2. It is concluded that PGD2 increases the stimulation-evoked release of norepinephrine from adrenergic nerves innervating the arterial wall. PGD2 appears to act differently on receptive sites responsible for increasing the release of norepinephrine and for producing arterial contraction. 相似文献
976.
In the present study VIP-immunoreactive (IR) nerve fibers were found in the skin of several mammalian species (cat, dog, pig and man). They supplied predominantly the arteries and arterial portions of arteriovenous anastomoses. Far fewer VIP-IR nerve fibers innervated veins and arterioles. Capillaries were supplied by VIP-IR fibers only in sweat and Meibomian glands. Some non-vascular VIP-IR nerve fibers were seen in contact with dermal smooth muscle strands. In eccrine sweat glands and in Meibomian glands VIP-IR fibers were targeting glandular cells. In addition, VIP-IR nerve fibers innervated the upper parts of facial hair follicles. In non-neuronal localization VIP-IR occurred in Merkel cells in all species and sites, while the intraepidermal axons consistently were not VIP-IR. Radioimmunoassay of different skin regions of cats also suggested both a neuronal and a Merkel cell origin of VIP-IR. Under physiological conditions VIP which is released from its neuronal and non-neuronal cutaneous pools may have an impact on thermoregulation by influencing blood flow and sweat production. It may also modulate axon-endings in Merkel cell-axon complexes and hair follicle receptors. Under pathological conditions an enhanced release of cutaneous VIP may lead to local inflammatory processes partly mediated via release of histamine from cutaneous mast cells. 相似文献
977.
Noboru Tomioka Kazuo Shinozaki Masahiro Sugiura 《Molecular & general genetics : MGG》1981,184(3):359-363
Summary Two PstI fragments (5.3x106 and 4.3x106 daltons) coding for Anacystis nidulans rRNA genes were cloned. The cloned rDNAs were characterized by restriction endonuclease mapping, DNA-RNA hybridization analysis and the R-loop technique. The results indicated that both fragments contained 16S, 23S and 5S rRNA genes in this order. A tRNA gene(s) was detected in the spacer region between 16S and 23S rRNA genes. The organization of A. nidulans rRNA genes resembles those of E. coli and of Euglena chloroplasts rather than those of higher plant chloroplasts. 相似文献
978.
979.
Saburo Tamura Nobutaka Takahashi Takao Yokota Noboru Murofushi Yukiyoshi Ogawa 《Planta》1967,78(2):208-212
Summary The presence of three water-soluble gibberellins was confirmed in immature seeds of morning-glory (Pharbitis nil). The structure of the main component has been elucidated as 2-O--glucosyl-gibberellin A3. It shows marked growth-promoting activity on rice seedlings but is far less active on dwarf maize mutants d
1, d
2 and d
5. 相似文献
980.
Fujitani Noboru Kawaguchi Naomasa Toda Shuji Matsumura Sueo Kimura Hiroshi Onishi Shunzo 《Molecular and cellular biochemistry》1997,169(1-2):73-78
An immunocytochemical study was performed to examine the expression of cellular c-myc protein in the heart of 30-, 120- and 180-day-old cardiomyopathic Syrian UM-X7.1 hamsters. The heart of age- and sex-matched BIO-RB hamster was used as normal control. In paraffin sections, an immunostaining for c-myc was markedly increased in cytoplasm of cells from the UM-X7.1 heart as compared with that of the BIO-RB heart which showed a weak staining. However, c-myc was localized in nuclei of cells in frozen sections of the heart. Specific cell types of the heart were differentiated with anti-vimentin, and we found that the increased expression of c-myc was present in nuclei of muscle cells of the UM-X7.1 myocardium. A quantitative study of c-myc-positive nuclei of muscle and nonmuscle cells was carried out by a video micrometer. The mean number of c-myc-positive nuclei of muscle cells was significantly higher in the cardiomyopathic heart than in the control heart from hamsters of all ages studied. These results suggest that the increase of c-myc protein may relate to the pathological state or pathogenesis of the hereditary cardiomyopathy. 相似文献