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91.
Krimer LS; Herman MM; Saunders RC; Boyd JC; Hyde TM; Carter JM; Kleinman JE; Weinberger DR 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):732-739
The entorhinal cortex (ERC) has been implicated in schizophrenia by a
number of studies. There is anatomical observation of neuronal heterotopias
in the rostral ERC, which is consistent with a hypothesis of
neurodevelopmental abnormalities in this disease. In view of the
significant cytoarchitectonic variation of the ERC throughout its
rostro-caudal extent, we performed a detailed subareal analysis of the
rostral two-thirds of the entorhinal cortex (ERCr) in 14 postmortem
schizophrenic brains and 14 matched controls (mean ages of 48 and 47
respectively). This systematic evaluation included both a qualitative
microscopic analysis of morphogenetic anomalies that would be consistent
with neurodevelopmental pathology and quantitative measurements of total
neuronal number, average neuronal density, laminar volume and laminar depth
from the cortical surface in cytoarchitectonically matched subareas of
schizophrenic and control brains. Parcellation of the entire ERC on the
basis of cytoarchitectonic criteria identified five distinct regions,
similar to those described in the macaque, except that in the human brain
three of the regions were further divisible into two or three subareas,
yielding nine distinct cellular compartments. Five rostral areas, prorhinal
(Pr), lateral (28L), intermediate rostral and caudal (281r and 281c), and
sulcal (28S), comprise the ERCr. Gross and microscopic examination of these
subdivisions throughout the ERCr failed to reveal laminar disorganization
in any of the schizophrenic brains. The brains also did not differ
significantly with respect to total neuronal number, total volume and
neuronal density per laminar and subareal subdivision, or laminar thickness
per entorhinal subarea. However, neuronal number and density were reduced
by 12-18% in Pr and 28L, suggesting that mild quantitative abnormalities
may exist in the ERCr and might possibly be revealed in a larger sample of
schizophrenic brains. We have failed to confirm previous reports of laminar
disorganization in the ERCr in brains of patients with schizophrenia; to
the extent that this region is implicated in schizophrenia, the structural
changes are likely to consist of more subtle cellular disturbances.
相似文献
92.
Oberyszyn TM; Conti CJ; Ross MS; Oberyszyn AS; Tober KL; Rackoff AI; Robertson FM 《Carcinogenesis》1998,19(3):445-455
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate
adherence of leukocytes to vascular endothelium and the associated ligand,
intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2
integrin proteins to allow transendothelial migration of leukocytes into
sites of inflammation. The present study examines the function of these
proteins in a murine model of acute cutaneous inflammation induced
following topical application of 12-O- tetradecanoylphorbol-13-acetate
(TPA) to the dorsal epidermis of SENCAR mice and in a model of skin
multistage carcinogenesis. At 24 h following topical application of TPA to
the dorsal epidermis of mice, dermal leukocytes expressed higher levels of
beta2 integrin protein compared with the lower levels of beta2 integrin
protein expression by peripheral blood leukocytes. ICAM-1 protein was
localized to epidermal keratinocytes and vascular endothelium in
TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.)
injection of either 50 microg anti-beta2 integrin antibody alone or in
combination with anti-ICAM-1 antibody significantly inhibited both
TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and
myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P
< 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but
had no effect on TPA-induced epidermal hyperplasia. In addition, injection
of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in
combination with anti-beta2 integrin antibody (P < 0.001) significantly
inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8-
OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2
integrin/ICAM-1 adhesion molecules work in concert to regulate migration,
retention and functional activation of leukocytes within the dermis during
TPA-induced skin inflammation and within stromal tissue of papillomas that
form during multi-stage carcinogenesis. Agents that inhibit these
receptor/ligand interactions may be useful in defining the roles of
specific cell populations in cutaneous inflammation and multistage
carcinogenesis and may also have potential as anti-promoting and
anti-progression agents.
相似文献
93.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
94.
一阶导数差示脉冲极谱法的建立及在药物分析中的应用 总被引:11,自引:0,他引:11
本文研究了一阶导数差示脉冲极谱法,并将其运用于扑尔敏、氟哌啶醇、维生素B6及其制剂的定量分析中。方法简便、快速、灵敏、结果准确。 相似文献
95.
Alpha 4 beta 1-integrin expression on sickle reticulocytes: vascular cell adhesion molecule-1-dependent binding to endothelium 总被引:7,自引:4,他引:7
Important complications in sickle cell anemia occur secondary to vascular occlusion, which is postulated to be initiated by interactions of erythrocytes with vascular endothelial cells. In patients with sickle cell anemia, up to 25% of reticulocytes express the alpha 4 beta 1-integrin complex. Furthermore, erythrocytes from patients with sickle cell anemia bind to endothelial cells activated by tumor necrosis factor alpha via (TNF alpha) via interactions between erythrocyte alpha 4 beta 1 and endothelial cell vascular cell adhesion molecule-1 (VCAM- 1). Thus, binding of alpha 4 beta 1-expressing reticulocytes to cytokine-activated endothelial cells may initiate vascular complications in sickle cell anemia and perhaps other hemolytic anemias during episodes of infection and inflammation. 相似文献
96.
Immunity in cattle vaccinated against ringworm 总被引:1,自引:0,他引:1
Protective properties of a live, freeze-dried vaccine against ringworm, produced by Bioveta, Ivanovice na Hané, Czechoslovakia, were tested in a group of 422 calves. Vaccinated and control calves were challenged by epicutaneous inoculation of a virulent culture of Trichophyton verrucosum. Between 4.4 and 9.5% of calves challenged between days 14 and 25 after revaccination showed only mild clinical signs of ringworm and 99-100% were fully protected from day 28, the immunity persisting for at least one year. All control calves showed signs of ringworm after challenge. In most cases, extensive mycotic lesions, also penetrating into deep skin layers, were observed. Protective properties of the Czechoslovak vaccine and a USSR vaccine were high and comparable. 相似文献
97.
98.
Krimer LS; Hyde TM; Herman MM; Saunders RC 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):722-731
The entorhinal cortex (ERC) has been implicated in the pathophysiology of
Alzheimer's disease, schizophrenia and other disorders affecting cognitive
functions. While powerful anatomical and histochemical methods
(immunohistochemistry, in situ hybridization, etc.) may be applied
(although with limitations) to postmortem human brain, each analysis should
utilize a cytoarchitectonic approach to provide appropriate comparisons
within the subdivisions of the ERC. Accordingly, we describe here the
normal cyto- and myeloarchitecture of the human ERC as a prerequisite for
the accompanying study of this region in schizophrenia. Our parcellation of
this cortex differs from previous treatments in three ways. First, we
adopted specific criteria of inclusion to define each subdivision of the
region. Although distinctive ERC features are most prominent in the
intermediate portion of this region, at least one of these features was
considered the minimum necessary criterion to include adjacent tissue in
the entorhinal area. Second, we used morphometric measurements (neuronal
size and density as well as subdivisional volume and laminar thickness) to
support our qualitative evaluation. Third, we have applied to the human ERC
the conventional cytoarchitectonic nomenclature of the entorhinal cortex
used previously in studies of non-human primates. This allows a more
accurate extrapolation of the available numerous experimental anatomical,
physiological and psychological data on this region to the human. As in the
monkey, the five main subareas were recognized in the human (prorhinal,
lateral, intermediate, sulcal and medial) but three required further
subdivision (intermediate, sulcal and medial). The morphometric results
obtained suggested a progression of the human entorhinal cortex from the
peripheral to the central subareas, with the intermediate subarea (281) as
the most complete entorhinal subdivision. Compared with non-human primates,
the human ERC not only retains the basic periallocortical organization but
also demonstrates further evolution. Taken together with available
experimental data on the connectivity of this brain region, these results
provide an anatomical basis for evaluating the ERC in human behavior.
相似文献
99.