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71.
Morphogenesis of nonpolypoid colorectal adenomas and early carcinomas assessed by cell proliferation and apoptosis 总被引:4,自引:0,他引:4
Nomura M Watari J Yokota K Saitoh Y Obara T Kohgo Y 《Virchows Archiv : an international journal of pathology》2000,437(1):17-24
Nonpolypoid neoplasms, as well as ordinary polypoid tumours, are occasionally found in the colorectum. To clarify whether
cell kinetic status affects the macroscopic morphology of colorectal neoplasms, we investigated proliferative indices (PI),
apoptotic indices (AI), and the expression of apoptosis-related gene products. We examined 110 colorectal neoplasms comprised
of 36 polypoid, 38 flat elevated and 36 depressed tumours. According to WHO’s criteria these tumours consisted of 61 adenomas
with low grade dysplasia (LGD), 30 adenomas with high grade dysplasia (HGD) and 19 carcinomas with submucosal invasion. Apoptotic
cells were detected by TUNEL staining. Proliferating cells and apoptosis-related gene products were assessed by immunohistochemistry
for Ki-67, p53, Bcl-2, and Bax antigens. AI were closely associated with macroscopic morphology in adenomas but not in carcinomas.
PI were relatively constant among the three macroscopic types in adenomas and carcinomas. Median AI values of polypoid, flat
elevated and depressed tumours were 1.8%, 2.1% and 4.6% for adenomas with LGD, 0.8%, 2.4% and 6.2% for adenomas with HGD and
2.9%, 4.0% and 3.6% for carcinomas, respectively. Overall PI were significantly higher in carcinomas than in adenomas with
LGD, whereas AI were not different. Although the incidence of expression was significantly higher in carcinomas for p53 and
in adenomas for Bcl-2 than the others, the expression of apoptosis-related gene products (p53, Bcl-2 and Bax) was similar
among polypoid, flat elevated and depressed tumours. Macroscopic morphology of colorectal adenomas is determined by the apoptosis
not by proliferation, and high apoptosis found in depressed adenomas implies their low net growth.
Received: 1 July 1999 / Accepted: 17 January 2000 相似文献
72.
Shimizu C Hasegawa T Tani Y Takahashi F Takeuchi M Watanabe T Ando M Katsumata N Fujiwara Y 《Human pathology》2004,35(12):201-1542
Insulin-like growth factor-1 receptor (IGF-1R) has been implicated in regulation in tumor growth. The results of previous studies performed by radioimmunoassay are conflicting, and the prognostic significance of IGF-1R expression in primary breast cancer is still controversial. IGF-1R expression was evaluated in formalin-fixed, paraffin-embedded tissue of 210 primary breast cancer patients by using anti-IGF-1R antibody. The clinicopathologic variables and 5-year disease-free survival were studied, and their correlations between IGF-1R expressions were investigated. IGF-1R overexpression was observed in 43.8% of tumors. IGF-1R overexpression had no correlation with prognosis or with other clinicopathologic parameters, such as age, tumor size, nodal status, histologic grade, hormone receptor status, and human epidermal growth factor 2 status. Though its prognostic value in breast cancer is limited, immunohistochemical evaluation of IGF-1R by using this monoclonal antibody may be useful in translational research using archived material. 相似文献
73.
Hirano H Ezura Y Ishiyama N Yamaguchi M Nasu I Yoshida H Suzuki T Hosoi T Emi M 《Journal of human genetics》2003,48(6):288-292
Natural tooth loss represents a major medical issue within the elderly population, since it impairs masticatory function critical
for oral intake of essential nutrition. Contribution of genetic factors has been implicated in the determination of natural
tooth loss; degree of reduction in number of natural teeth remaining intact (NTI) varies among individuals; thus, heterogeneity
in NTI might reflect genetic variation within the population. One candidate gene, the matrix Gla protein gene (MGP), has been implicated in the pathogenesis of bone loss through a repression of bone/tooth formation. We have investigated
a possible association between the CA repeat polymorphism at the human MGP gene locus and the NTI in 458 elderly Japanese women. In 916 chromosomes tested, ten alleles of the polymorphic nucleotide
repeat were observed (designated A1–A10), among which five alleles were regarded as major alleles to be tested for the association.
Twenty-seven women who possessed an A6 allele (164 bp) had significantly higher NTI than the remaining participants (n=431), who did not carry an allele of that size (mean: 10.0 teeth vs 5.6 teeth; P=0.007, Mann-Whitney test). An eight-year longitudinal follow-up study of NTI suggested that the genetic variations at the MGP locus did not affect the rate of tooth loss in the elderly period. These results suggest that genetic variation at the MGP gene locus is associated with some determinants for tooth loss in elderly women. 相似文献
74.
Takada D Emi M Ezura Y Nobe Y Kawamura K Iino Y Katayama Y Xin Y Wu LL Larringa-Shum S Stephenson SH Hunt SC Hopkins PN 《Journal of human genetics》2002,47(12):0656-0664
75.
Yoshinao Oda Masazumi Tsuneyoshi Hiroshi Hashimoto Toshimitsu Iwashita Masahiro Ushijima Sachio Masuda Yukihide Iwamoto Yoichi Sugioka 《Virchows Archiv : an international journal of pathology》1993,423(1):65-69
Primary rhabdomyosarcoma of bone is exceedingly rare. We present a case of rhabdomyosarcoma of the iliac bone in a 32-year-old male. Histologically, the tumour consisted mainly of a uniform proliferation of elongated spindle cells arranged in a herring bone pattern, simulating fibrosarcoma. Focally there was a conventional embryonal pattern with scattered rhabdomyoblasts possessing an eosinophilic cytoplasm. Immunohistochemical studies disclosed expression of muscle markers such as desmin and muscle-specific actin, in both the embryonal and spindle-cell areas and myoglobin only in the embryonal areas. Such histological features are unusual for classical embryonal rhabdomyosarcoma. The anatomical site and age of the patient are also atypical. 相似文献
76.
Genesis of pulmonary foam cells in rats with diet-induced hyper beta-lipoproteinaemia 总被引:1,自引:0,他引:1
K Shibuya M Tajima J Yamate T Saitoh S Sannai 《International journal of experimental pathology》1991,72(4):423-435
Hyper beta-lipoproteinaemia in rats was produced by feeding a standard diet to which was added excess cholesterol and cholic acid, with or without olive oil, for 4, 8, and 12 weeks. The beta-lipoprotein percentage in serum lipoprotein electrophoresis and lipid contents in very low density lipoprotein and low density lipoprotein fractions in these rats were significantly higher than in the control rats fed the standard diet only. The percentage of foamy monocytes (FMs) to the total number of blood monocytes (BMs) from mononuclear leucocyte fractions and percentage of pulmonary foam cells (PFCs) to the number of alveolar macrophages (AMs) from bronchopulmonary lavage fluids in the rats increased with the extension of the feeding period and were significantly higher than those in the controls. An increase in the percentage of PFCs was closely correlated with that of FMs in the rats. FMs and PFCs had cytoplasmic fine vacuoles proved to be neutral lipid and cholesterol. Histologically, PFCs made an appearance in the lungs of all the rats as early as 4 weeks after the start of feeding. The degree of the PFCs' development increased as the feeding period lengthened. When latex particles were injected intravenously into rats at feeding week 4, the percentage of latex-ingested AMs to the number of AMs in the rats was significantly higher than that of the controls at 4 and 8 days post-injection. The percentage of latex-ingested PFCs to the number of latex-ingested AMs increased with the lapse of a day after injection and was significantly higher than that of the controls at 2, 4, and 8 days post-injection. The present findings suggest that the foamy transformation of BMs and their migration into the pulmonary alveoli may be a potential mechanism of the PFCs' development in rats with hyper beta-lipoproteinaemia. 相似文献
77.
Haruyo Nakajima PhDa Satoshi Hachimuraa Shinya Nishiwakia Toshiyuki Katsuki MD PhDb Naoki Shimojo MD PhDb Akio Ametani PhDa Yoichi Kohno MD PhDb Shuichi Kaminogawa PhDa 《The Journal of allergy and clinical immunology》1996,97(6):1342-1349
To study cow’s milk allergy at the cellular level, we assessed the reactivity of peripheral blood mononuclear cells from patients allergic to cow’s milk to αs1-casein, which is one of the major allergens in cow’s milk. Proliferation of the cells to αs1-casein activation showed a rather weak response. Therefore to understand T-cell reactivity to αs1-casein in more detail, we prepared αs1-casein–specific T-cell lines from patients allergic to cow’s milk and established 26 T-cell lines. These T-cell lines could be classified into three groups by analyzing their surface marker expression: those containing predominantly CD4+CD8- T cells, those containing both CD4+CD8- and CD4-CD8+ T cells, and those containing predominantly CD4-CD8+ T cells. The CD8+ T cells were obtained at an unexpectedly higher frequency from the patients. These T-cell lines produced interferon-γ and IL-4. These results suggest that CD8+ T cells specific for αs1-casein and CD4+ T cells were primed by the stimulation with αs1-casein in patients allergic to milk and that both T cells may play a key role in the onset, progression of, or recovery from cow’s milk allergy. (J ALLERGY CLIN IMMUNOL 1996;97:1342-9.) 相似文献
78.
Mirani V. Weerasooriya Takahiro Fujino Yoichi Ishii Noboru Kagei 《Parasitology research》1986,72(6):765-778
We studied larval nematodes of four genera of the Anisakidae using a scanning electron microscope (SEM). The anterior and posterior extremities and cuticular structures of the 3rd-stage larvae (L3) ofAnisakis type I,Pseudoterranova decipiens, Contracaecum type B andHysterothylacium were examined. The 4th-stage larvae (L4) ofAnisakis type I,P. decipiens, recovered after infection into laboratory rats, and the L3 and L4 ofAnisakis type I larvae from human were also examined in the same way. There were generic differences in the shape and size of the lip bulges, external papillary structures, the appearance of the boring tooth, the width and depth of the grooves and ridges of the cuticle and the caudal structures of the L3. InAnisakis type I andP. decipiens L3, changes were seen in the anterior extremity, cuticle and posterior extremity after molting to the L4. Similar changes can be expected in larvae infecting man. The L4 ofAnisakis type I from rat and man were similar, while the L4 ofAnisakis type I andP. decipiens showed differences. These ultrastructural differences might be of value in the identification of fragments recovered during endoscopy in man. 相似文献
79.
Dr. S. Shiosaka M. Tohyama H. Takagi Y. Takahashi Y. Saitoh T. Sakumoto H. Nakagawa N. Shimizu 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(4):377-388
Summary The ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.Abbreviations used in Figures and Tables a
nucleus accumbens
- abl
nucleus amygdaloideus basalis, pars lateralis
- abm
nucleus amygdaloideus basalis, pars medialis
- ac
nucleus amygdaloideus centralis
- AC
anterior cingulate area
- al
nucleus amygdaloideus lateralis
- am
nucleus amygdaloideus medialis
- ar
nucleus arcuatus
- CC
tractus corporis callosi
- CSDV
commissura supraoptica dorsalis, pars ventralis
- DB
diagonal band
- DM
nucleus dorsomedialis hypothalami
- EP
nucleus entopeduncularis
- ha
nucleus anterior hypothalami
- hl
nucleus lateralis hypothalami
- hp
nucleus posterior hypothalami
- IL
infralimbic area of frontal cortex
- lh
nucleus habenulae lateralis
- LH1
medial forebrain bundle (MFB) at the level of commissura anterior
- LH2
lateral preoptic area
- LH3
MFB at the level of the nucleus anterior hypothalami
- LH4
MFB at the level of the nucleus ventromedialis hypothalami
- LH5
MFB at the level of the nucleus posterior hypothalami
- MFB
medial forebrain bundle
- pf
nucleus parafascicularis
- PL
prelimbic area of frontal cortex
- pol
nucleus preopticus lateralis
- pom
nucleus preopticus medialis
- posc
nucleus preopticus, pars suprachiasmatica
- pt
nucleus parataenialis
- pv
nucleus premamillaris ventralis
- PV
nucleus paraventricularis
- pvs
nucleus periventricularis stellatocellularis
- pvr
nucleus periventricularis rotundocellularis
- SC
sulcal cortex
- SGPV
substantia grisea periventricularis
- SI
substantia innominata
- SL
lateral septal nucleus
- ST
bed nucleus of stria terminalis
- sum
nucleus supramamillaris
- TO
tractus opticus
- tmm
nucleus medialis thalami, pars medialis
- VM
nucleus ventromedialis hypothalami
The nomenclature used in this paper is according to König and Klippel's Stereotaxic Atlas (1967). 相似文献
80.
Recent advances in human genome research have revealed that genetic polymorphisms, such as single nucleotide polymorphisms (SNPs), are closely associated with susceptibility to various common diseases and adverse drug reactions. Also, numerous mutations responsible for a number of genetic diseases have been identified. Clinical application of genetic information to individual health care requires simple and rapid identification of nucleotide changes in clinical settings. We have devised a novel low-tech method for the detection of a single nucleotide substitution using competitive allele-specific short oligonucleotide hybridization with immunochromatographic strip. The gene of interest is PCR-amplified, hybridized to an allele-specific short oligonucleotide probe in the presence of a competitive oligonucleotide, and subjected to chromatography using a DNA test strip at room temperature. The genotype is unambiguously determined by the presence or the absence of visible purple lines on a strip. Feasibility of the method was demonstrated by the detection of a prevalent disease-causing mutations in glycogen storage disease type Ia (G6PC), medium-chain acyl-CoA dehydrogenase deficiency (ACADM), non-ketotic hyperglycinemia (GLDC), and clinically important polymorphisms in the CYP2C19 gene and the aldehyde dehydrogenase 2 gene (ALDH2). The procedure does not demand either technical expertise or expensive instruments and is readily performed in local clinical laboratories. The result is obtained within 10 min after PCR. This rapid and simple method of SNP detection may be used for point-of-care genetic diagnosis with potentially diverse clinical applications. Hum Mutat 22:166-172, 2003. 相似文献