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991.
Summary The light-evoked response pattern and morphology of one interplexiform cell were studied in the goldfish retina by intracellular recording and staining. The membrane potential of the cell spontaneously oscillated in the dark. In response to a brief light stimulus, the membrane potential initially gave a slow transient depolarization. During maintained light, the oscillations showed a tendency to be suppressed; the response of the cell to the offset of the stimulus was not so prominent. The perikaryon of the interplexiform cell was positioned at the proximal boundary of the inner nuclear layer. The cell had two broad layers of dendrites; one was diffuse in the inner plexiform layer, the other was more sparse in the outer plexiform layer. The morphological and electrophysiological characteristics of the cell are discussed in relation to dopaminergic interplexiform cells and the light-evoked release pattern of dopamine in the teleost retina. 相似文献
992.
Michel Goldberg Jacqueline Feinberg Sylvie Lecolle Marcia A. Kaetzel Dominique Rainteau James L. Lessard John R. Dedman Serge Weinman 《Cell and tissue research》1991,263(1):81-89
Summary Annexin VI and actin were detected by immunoblot analysis in the enamel- and dentin-related portions of dental tissues. Annexin VI was found mainly in the particulate fraction whereas actin was detected in both the soluble and particulate fractions. By immunoelectron microscopy, annexin VI antibodies conjugated with colloidal gold were seen to label the mitochondria, the cytosol and the nucleus of secretory ameloblasts and odontoblasts of rat incisor. In the processes of these cell, the plasmalemmal undercoat was labeled. Antiactin antibodies labeled the desmosome-like junctions, the cytosol, and the mitochondria of the cell bodies. Extensive labeling was seen at the periphery of the Tomes' processes and odontoblast processes. These results suggest that annexin VI may play a role in Ca2+-regulation in the cell bodies, especially as a calcium receptor protein in the mitochondria. Moreover, annexin VI and actin seem to be co-distributed in secretory processes. Thus, these proteins might be both involved in exocytotic and endocytotic events. 相似文献
993.
N. Aste C. Viglietti-Panzica A. Fasolo C. Andreone H. Vaudry G. Pelletier G. C. Panzica 《Cell and tissue research》1991,265(2):219-230
Summary In the present study, we have demonstrated, by means of the biotin-avidin method, the widespread distribution of neuropeptide Y (NPY)-immunoreactive structures throughout the whole brain of the Japanese quail (Coturnix coturnix japonica). The prosencephalic region contained the highest concentration of both NPY-containing fibres and perikarya. Immunoreactive fibres were observed throughout, particularly within the paraolfactory lobe, the lateral septum, the nucleus taeniae, the preoptic area, the periventricular hypothalamic regions, the tuberal complex, and the ventrolateral thalamus. NPY-immunoreactive cells were represented by: a) small scattered perikarya in the telencephalic portion (i.e. archistriatal, neostriatal and hyperstriatal regions, hippocampus, piriform cortex); b) medium-sized cell bodies located around the nucleus rotundus, ventrolateral, and lateral anterior thalamic nuclei; c) small clustered cells within the periventricular and medial preoptic nuclei. The brainstem showed a less diffuse innervation, although a dense network of immunopositive fibres was observed within the optic tectum, the periaqueductal region, and the Edinger-Westphal, linearis caudalis and raphes nuclei. Two populations of large NPY-containing perikarya were detected: one located in the isthmic region, the other at the boundaries of the pons with the medulla. The wide distribution of NPY-immunoreactive structures within regions that have been demonstrated to play a role in the control of vegetative, endocrine and sensory activities suggests that, in birds, this neuropeptide is involved in the regulation of several aspects of cerebral functions.Abbreviations
AA
archistriatum anterius
-
AC
nucleus accumbens
-
AM
nucleus anterior medialis
-
APP
avian pancreatic polypeptide
-
CNS
centrai nervous system
-
CO
chiasma opticum
-
CP
commissura posterior
-
CPi
cortex piriformis
-
DIC
differential interferential contrast
-
DLAl
nucleus dorsolateralis anterior thalami, pars lateralis
-
DLAm
nucleus dorsolateralis anterior thalami, pars medialis
-
E
ectostriatum
-
EW
nucleus of Edinger-Westphal
-
FLM
fasciculus longitudinalis medialis
-
GCt
substantia grisea centralis
-
GLv
nucleus geniculatus lateralis, pars ventralis
-
HA
hyperstriatum accessorium
-
Hp
hippocampus
-
HPLC
high performance liquid chromatography
-
HV
hyperstriatum ventrale
-
IF
nucleus infundibularis
-
IO
nucleus isthmo-opticus
-
IP
nucleus interpeduncularis
-
IR
immunoreactive
-
LA
nucleus lateralis anterior thalami
-
LC
nucleus linearis caudalis
-
LFS
lamina frontalis superior
-
LH
lamina hyperstriatica
-
LHRH
luteinizing hormone-releasing hormone
-
LoC
locus coeruleus
-
LPO
lobus paraolfactorius
-
ME
eminentia mediana
-
N
neostriatum
-
NC
neostriatum caudale
-
NPY
neuropeptide Y
-
NIII
nervus oculomotorius
-
NV
nervus trigeminus
-
NVI
nervus facialis
-
NVIIIc
nervus octavus, pars cochlearis
-
nIV
nucleus nervi oculomotorii
-
nIX
nucleus nervi glossopharyngei
-
nBOR
nucleus opticus basalis (ectomamilaris)
-
nCPa
nucleus commissurae pallii
-
nST
nucleus striae terminalis
-
OM
tractus occipitomesencephalicus
-
OS
nucleus olivaris superior
-
PA
palaeostriatum augmentatum
-
PBS
phosphate-buffered saline
-
POA
nucleus praeopticus anterior
-
POM
nucleus praeopticus medialis
-
POP
nucleus praeopticus periventricularis
-
PP
pancreatic polypeptide
-
PYY
polypeptide YY
-
PVN
nucleus paraventricularis magnocellularis
-
PVO
organum paraventriculare
-
R
nucleus raphes
-
ROT
nucleus rotundus
-
RP
nucleus reticularis pontis caudalis
-
Rpc
nucleus reticularis parvocellularis
-
RPgc
nucleus reticularis pontis caudalis, pars gigantocellularis
-
RPO
nucleus reticularis pontis oralis
-
SCd
nucleus subcoeruleus dorsalis
-
SCv
nucleus subcoeruleus ventralis
-
SCNm
nucleus suprachiasmaticus, pars medialis
-
SCNl
nucleus suprachiasmaticus, pars lateralis
-
SL
nucleus septalis lateralis
-
SM
nucleus septalis medialis
-
Ta
nucleus tangentialis
-
TeO
tectum opticum
-
Tn
nucleus taeniae
-
TPc
nucleus tegmenti pedunculo-pontinus, pars compacta
-
TSM
tractus septo-mesencephalicus
-
TV
nueleus tegmenti ventralis
-
VeL
nucleus vestibularis lateralis
-
VLT
nucleus ventrolateralis thalami
-
VMN
nucleus ventromedialis hypothalami
A preliminary report of this study was presented at the 15th Conference of European Comparative Endocrinologists, Leuven, Belgium, September 1990 相似文献
994.
Summary A single neuronal cell assay of neurite growth was utilized to determine types and domains of neuronal proteoglycans involved in neurite growth on laminin. Perturbations of biosynthesis and processing, enzymatic digestion with specific lyases, and competition with glycosaminoglycan side chains produced complementary data consistent with a molecular model implicating glycosaminoglycan (GAG) residues of heparan sulphate proteoglycans (HSPGs) in neurite growth. The observations suggest that HSPGs promote neurite growth on laminin by bridging between binding domains for HSPGs on laminin and on the neuronal cell surface, and that the bridge is tethered at both ends by noncovalent interactions between the binding domains and GAG side chains. Sulphation of the GAGs of HSPGs appears to be critical to the tethering and/or neurite growth-promoting activity of neuronal HSPGs. 相似文献
995.
Uwe Wolfrum 《Cell and tissue research》1991,266(2):231-238
Summary Long ciliary rootlets are a characteristic feature of the dendritic inner segments of the sensory cells in insect sensilla. These rootlets are composed of highly ordered filaments and are regularly cross-striated. Collagenase digestion and immunohistochemistry reveal that the rootlets are probably not composed of collagen fibers. However, double-labeling experiments with phalloidin and anti--actinins show that antibodies to -actinin react with the ciliary rootlets of the sensilla, but do not stain the scolopale, which is composed of actin filaments as visualized by phalloidin. Antibodies to centrin, a contractile protein isolated from flagellar rootlets of green algae, also stain the ciliary rootlets. Within the ciliary rootlets of insect sensilla, -actinin may be associated with filaments other than actin filaments. The immunohistochemical localization of a centrin-like protein suggests that contractions probably occur within the rootlets. The centrin-like protein may play a role during the mechanical transduction or adaptation of the sensilla. 相似文献
996.
Summary Adult rainbow trout (Oncorhynchus mykiss) were injected intraperitoneally with capsaicin, substance P, serotonin, or a control of saline vehicle or bovine serum albumin (0.5 g/g body weight). Fish were sacrificed 30 min and 1,2 and 4 h post-injection, the gut was dissected out, and a small section of the upper intestine was processed for electron microscopy. A significant proportion of eosinophilic granule cells (EGCs) of the intestine were in close association with non-myelinated neuronal bundles in all fish (4 fish per treatment and time period), but there was no significant difference between treatment or time, suggesting that the association was unaffected by these factors. Close examination of EGC ultrastructure showed that fish treated with capsaicin and substance P exhibited limited degranulation of the EGCs in the stratum compactum and extensive crinophagic-like degranulation in the lamina propria. Cells of the lamina propria contained characteristic multivesicular-like bodies. The degranulation was reminiscent of both mast cell degranulation and endocrine cell crinophagy. EGCs of fish treated with serotonin or a control were unaffected, suggesting that the serotoninergic neurons, believed to be involved in gut motility, were not responsible for degranulation. It is apparent that EGCs of the trout intestine may be under nervous control, as has been demonstrated previously for mammalian mast cells. 相似文献
997.
Uwe Wolfrum 《Cell and tissue research》1991,265(1):11-17
Summary Immuno-electron microscopy confirms that the scolopale, a characteristically prominent cytoskeletal element of insect scolopidia, is composed mainly of actin filaments. Immunohistochemistry reveals that these filaments are co-localized with tropomyosin. Myosin S1-decoration shows that their polarity is unidirectional. Antibodies to -actinin do not bind within the scolopale. The association of these actin filaments with tropomyosin in the absence of myosin, together with their uniform polarity, strongly suggests that, in the scolopale, they have a stabilizing rather than contractile function. Filament elasticity would appear to be important for stimulation. The degree of elasticity may well be governed by the extent of tropomyosin binding. 相似文献
998.
Summary By use of an antiserum against the crustacean cardioactive peptide (CCAP) several types of bilaterally symmetrical neurons have been mapped quantitatively in the ventral nerve cord and in the brain of the meal beetle, Tenebrio molitor. The general architecture of these neurons was reconstructed from peroxidase-antiperoxidase-labelled whole-mount preparations. From the subesophageal to the seventh abdominal ganglia two types of neurons show a repetitive organization of contralateral projection patterns in each neuromere. The first type has few branches in the central neuropil and a distinct peripheral projection. The second type is characterized by an elaborate central branching pattern, which includes ascending and descending processes. Some of its peripheral branches were found to supply peripheral neurohemal areas. In the protocerebrum, 10 CCAP-immunoreactive neurons occur with projections into the superior median protocerebrum and the tritocerebrum. Immunopositive neurons were mapped in larval and various pupal stages, as well as in the adult. All types of identified neurons were found to persist throughout metamorphosis maintaining their essential structural and topological characteristics. The CCAP-immunoreactive neurons of T. molitor are compared with those described for the locust. Putative structural homologies of subsets of neurons in both species are discussed. 相似文献
999.
Yoshihiro Toh Akiko Mizutani Fuminori Tokunaga Tatsushi Muta Sadaaki Iwanaga 《Cell and tissue research》1991,266(1):137-147
Summary The structure of hemocytes in the normal state and during blood coagulation, and the intracellular localization of three clotting factors and two antimicrobial factors were examined in the Japanese horseshoe crabTachypleus tridentatus. Two types of hemocytes were found in the circulating blood: non-granular and granular hemocytes. The latter contained numerous dense granules classed into two major types: L- and D-granules. The L-granules were larger (up to 1.5 m in diameter) and less electron-dense than the D-granules (less than 0.6 m in diameter). The L-granules contained three clotting factors and one antimicrobial factor, whereas the D-granules exclusively contained the other antimicrobial factor. After treatment with endotoxin, the L-granules were released more rapidly than the D-granules, although almost all granules were finally exocytosed. The granular hemocyte possessed a single Golgi complex; possible precursor granules of L-granules and D-granules contained tubular and condensed dense material, respectively. These data are discussed in relation to the self-defense mechanisms of the horseshoe crab. 相似文献
1000.
Summary The opioidergic, sympathetic and neuropeptide Y-positive innervation of the sphincter of Oddi (common bile duct sphincter and pancreatic duct sphincter), as well as other segments of the extrahepatic biliary tree was studied in the monkey by use of immunohistochemistry. Methionine-enkephalin-positive nerves were seen to innervate the smooth muscle of all portions of the sphincter of Oddi and also local ganglion cells. No methionine-enkephalin-positive nerves could be detected in the common bile duct, pancreatic duct or gallbladder. Tyrosine hydroxylase-positive nerves occurred between smooth muscle bundles and also ran to local ganglion cells as well as along the common bile duct. Neuropeptide Y-positive nerves were observed within smooth muscle of the sphincter of Oddi (all portions), common bile duct, pancreatic duct and gallbladder. No evidence of any differential innervation of the pancreatic duct and common bile duct sphincters could be detected with these markers. 相似文献