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51.
Sato A Taniguchi I Fujiwara D Ichikawa H Suzuki M Nawata S Murakami G 《Anatomical science international / Japanese Association of Anatomists》2003,78(4):211-222
Gaps and fragmentation of the superficial lymph node cortex are considered to provide intranodal shunt flow between the afferent
and efferent vessels. Using serial sections of 205 nodes obtained from 27 donated cadavers more than 70 years of age, we examined
the histological architecture of the abdominal and pelvic nodes in elderly Japanese. Secondary follicles were rare in the
specimens. Cortex gaps were, to a greater or lesser degree, found in all nodes. We classified these nodes into three types
according to how often the gap occurred. Type 1 nodes, with a relatively complete shield for the afferent lymph, were most
frequently found in gastric nodes, whereas type 3 nodes, with numerous gaps, were often observed in the colic, para-aortic
and pelvic nodes. The type 3 nodes showed a specific architecture characterized by a fragmented superficial cortex, three-dimensionally
assembled cords and a common sinus between them. Primary follicles were located in the assembled cord structures as well as
at the superficial cortex. Irrespective of the type, B and T lymphocyte areas were intermingled in the cortex-like areas.
The present results reveal region-specific histological heterogeneity in aged human visceral nodes. Due to increased surface
areas, the type 3 architecture seemed to accelerate systemic immunity rather than act as a local barrier in the para-aortic
and pelvic nodes, which are located centrally along the lymphatic drainage routes. However, thick trabeculae often seemed
to develop in the type 3 sinus to decrease nodal function with aging. 相似文献
52.
Ichiya Yamazaki MD PhD Norihisa Karube MD PhD Tamitaro Soma MD Yasuharu Noishiki MD PhD Yukio Ichikawa MD PhD 《Journal of artificial organs》2005,8(1):67-70
The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease. 相似文献
53.
Saijo K Schmedt C Su IH Karasuyama H Lowell CA Reth M Adachi T Patke A Santana A Tarakhovsky A 《Nature immunology》2003,4(3):274-279
The nature of signals that govern the development of immunoglobulin heavy chain-dependent B cells is largely unknown. Using mice deficient for the B cell-expressed Src-family protein tyrosine kinases (SFKs) Blk, Fyn and Lyn, we show an essential role of these kinases in pre-B cell receptor (pre-BCR)- mediated NF-kappaB activation and B cell development. This signaling defect is SFK specific, as a deficiency in Syk, which controls pre-B cell development, does not affect NF-kappaB induction. Impaired NF-kappaB induction was overcome by the activation of protein kinase C (PKC)-lambda, thus suggesting the involvement of PKC-lambda in pre-BCR-mediated SFK-dependent activation of NF-kappaB. Our data show the existence of a functionally distinct SFK signaling module responsible for pre-BCR-mediated NF-kappaB activation and B cell development. 相似文献
54.
Fumihiko Sasaki Yuji Ichikawa Shoji Yamauchi 《Anatomical record (Hoboken, N.J. : 2007)》1992,233(1):135-142
Adenohypophyses of porcine fetuses from 25 to 110 days of gestation were studied by immunohistochemical staining to ascertain the ontogeny of specific cell types and their spatial distribution in the pars distalis. No hormonecontaining cells were found before 30 days of gestation. ACTH cells were observed first at 40 days, while GH and LH cells appeared first at 60 days. PRL cells were initially detected at 105 days. ACTH immunoreactive cells were also observed in the pars intermedia at 40 days. Blood capillaries were interposed between cell cords of the pars distalis after 40 days of gestation. ACTH cells were evenly distribution in all areas of the pars distalis except the rostal area (sex zone). GH cells were densely distributed in lateral wings of the pars distalis and immediately anterior to Rathke's lumen. PRL cells resembled GH cells in their distribution pattern, but PRL cells were fewer in number. LH cells were scattered in the sex zone of the pars distalis from 60 to 80 days of gestation. After 90 days, they became scattered throughout the pars distalis but were more numerous in the sex zone than in other areas. The inductive elements of adenohypophysial cells from Rathke's pouch epithelia are discussed. We hypothesize that cell cords of specific areas facing Rathke's lumen may differentiate into specific cell types of the pars distalis during fetal life. © 1992 Wiley-Liss, Inc. 相似文献
55.
Tomoyuki Ichikawa Kyoko Ajiki Junko Matsuura Hidemi Misawa 《Journal of chemical neuroanatomy》1997,13(1):23-39
Choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) are proteins that are required for cholinergic neurotransmission. Present knowledge concerning the organization of cholinergic structures has been derived primarily from immunohistochemistry for ChAT. In the present study, we investigated the distribution of mRNAs and the corresponding proteins for ChAT and VAChT by in situ hybridization histochemistry and immunohistochemistry. The patterns of distribution of perikarya containing ChAT mRNA, ChAT protein, VAChT mRNA and VAChT protein were similar in most regions, and co-localization in the same neuron of mRNAs for ChAT and VAChT, that of ChAT mRNA and ChAT protein, and that of VAChT mRNA and VAChT protein were demonstrated. However, in the cerebral cortex and hypothalamus, ChAT-immunoreactive perikarya were present, but they did not contain mRNAs for ChAT and VAChT, and VAChT protein. On the other hand, in the cerebellum, Purkinje cell bodies contained VAChT mRNA and VAChT protein, but they did not contain either ChAT mRNA or ChAT protein. Axon bundles were clearly revealed by immunohistochemistry for ChAT, but they were not detected by that for VAChT. Both ChAT and VAChT antibodies revealed preterminal axons and terminal-like structures. In the forebrain, they were present in the olfactory bulb, nucleus of the lateral olfactory tract, olfactory tubercle, lateral septal nucleus, amygdala, hippocampus, neocortex, caudate-putamen, thalamus and median eminence of the hypothalamus. In the brainstem, they were localized in the superior colliculus, interpeduncular nucleus and some cranial nerve motor nuclei, and further in the ventral horn of the spinal cord. These results indicate strongly that ChAT and VAChT are expressed in most of the cholinergic neurons, and that immunohistochemistry for VAChT is as useful to detect cholinergic terminal fields as that for ChAT. 相似文献
56.
Ito Y Yoshida H Tomoda C Miya A Kobayashi K Matsuzuka F Yasuoka H Kakudo K Inohara H Kuma K Miyauchi A 《Pathology》2005,37(4):296-298
AIMS: Galectin-3, a member of the beta-galactoside binding family of lectins, has been regarded as a useful tool for discriminating malignant tumours from benign nodules of the thyroid, including the distinction between follicular carcinoma and adenoma. However, there are follicular tumours with unclear vascular or capsular invasion, which makes diagnosis more difficult. In this study, we investigated the relationship between galectin-3 expression and the degree of vascular or capsular invasion of follicular tumours. METHODS: We immunohistochemically investigated galectin-3 expression in 260 cases of follicular tumour with various degrees of vascular or capsular invasion classified into four categories. RESULTS: The galectin-3 expression level significantly increased with the degree of vascular or capsular invasion (p<0.0001). However, its diagnostic value for follicular carcinoma was not high because the sensitivity and specificity were 68.7% and 57.5%, respectively. CONCLUSIONS: Our findings suggest that galectin-3 plays a role in the transformation of follicular tumours from benign to malignant; however, when diagnosing follicular tumours, the presence of this protein should not be required for diagnosing malignant transformation in all cases. Therefore, we must conclude that galectin-3 should only be considered an adjuvant marker for follicular carcinoma. 相似文献
57.
The fourth-generation centrifugal blood pump 总被引:1,自引:0,他引:1
The NEDO Gyro permanently implantable (PI) centrifugal blood pump has been developed as a simple, durable, centrifugal blood
pump without a complex magnetic suspension system. In vitro studies were performed using a Gyro PI pump with the transparent
pump housing in a mock circuit. These studies revealed that the impeller transfers to a floating or a top contact condition,
which was dependent on the revolutions per minute (RPM). This pump can be easily converted from a left ventricular assist
device (LVAD) to a right ventricular assist device (RVAD) by simply adding a spacer between the pump and the actuator. In
order to optimize the impeller suspension for the LVAD and RVAD, spacers of the proper thickness are inserted between both
of the pumps and the actuators to regulate the magnetic force. Two Gyro PI pumps were implanted in a bovine model in a 3-month
biventricular assist device (BVAD) animal study. This experiment was electively terminated 90 days after implantation. All
of the parameters, including pump flow rate, power consumption, and plasma free hemoglobin, were in acceptable ranges. No
thrombus formation was observed in either pump. Antithrombogenesis and effectiveness were demonstrated in this animal study.
The NEDO Gyro PI pump is ready to move on to the 3-month preclinical system evaluation.
Received: February 28, 2002 / Accepted: May 30, 2002
Acknowledgment The New Energy and Industrial Technology Development Organization (NEDO) under the Ministry of Economy, Trade and Industry
of Japan financially supported this project.
Correspondence to:S. Ichikawa 相似文献
58.
Muneo Igarashi Nozomi Hosoda Yuki Bando Kaoru Shimanuki Wataru Sunaoshi Hiroyuki Shirai Hisao Miura 《Journal of clinical immunology》1992,12(5):335-340
An anticarbamazepine antibody was detected in the serum of a patient with severe carbamazepine-induced serum sickness. We found that the patient's T cells and IgG antibody recognized an epitope which appeared in subjects showing an allergic reaction, as well as that in subjects who showed no allergic reaction, after long-term carbamazepine therapy. These results show that an anti-carbamazepine immune response does not occur in the majority of subjects who undergo long-term carbamazepine therapy without developing allergic symptoms, although the immunodominant haptenic epitope of carbamazepine is present in their sera. 相似文献
59.
DNA-binding polarity of human replication protein A positions nucleases in nucleotide excision repair 总被引:15,自引:0,他引:15 下载免费PDF全文
Wouter L. de Laat Esther Appeldoorn Kaoru Sugasawa Eric Weterings Nicolaas G.J. Jaspers Jan H.J. Hoeijmakers 《Genes & development》1998,12(16):2598-2609
The human single-stranded DNA-binding replication A protein (RPA) is involved in various DNA-processing events. By comparing the affinity of hRPA for artificial DNA hairpin structures with 3′- or 5′-protruding single-stranded arms, we found that hRPA binds ssDNA with a defined polarity; a strong ssDNA interaction domain of hRPA is positioned at the 5′ side of its binding region, a weak ssDNA-binding domain resides at the 3′ side. Polarity appears crucial for positioning of the excision repair nucleases XPG and ERCC1–XPF on the DNA. With the 3′-oriented side of hRPA facing a duplex ssDNA junction, hRPA interacts with and stimulates ERCC1–XPF, whereas the 5′-oriented side of hRPA at a DNA junction allows stable binding of XPG to hRPA. Our data pinpoint hRPA to the undamaged strand during nucleotide excision repair. Polarity of hRPA on ssDNA is likely to contribute to the directionality of other hRPA-dependent processes as well. 相似文献
60.
Defective interleukin-1 production in a familial monocyte disorder with a combined abnormality of mobility and phagocytosis-killing. 下载免费PDF全文
A Komiyama M Ichikawa H Kanda K Aoyama K Yasui M Yamazaki H Kawai Y Miyagawa T Akabane 《Clinical and experimental immunology》1988,73(3):500-504
Monocytes in a familial monocyte disorder, a recently recognized primary immunodeficiency syndrome, with impaired phagocytic functions were studied for their ability to produce interleukin 1 (IL-1) as well as the surface property. Monocytes from two children (siblings) with the disorder possessed CD11b, CD13, CD14, CD33, Ia and LFA-1/Mac-1/p150,95 beta subunit antigens as determined by flow cytometry. Electron microscopic cytochemistry showed that the monocytes had surface glycoproteins reactive with four representative lectins. The IL-1 production by monocytes was assayed in the two patients and compared with that in six children with primary immunodeficiency syndromes and some monocyte abnormalities; three had congenital neutropenia, two had hyper-IgE syndrome, and one had defective monocyte chemotaxis. Monocyte culture supernatants were prepared with stimulation by lipopolysaccharide or silica, and their IL-1 activity was measured by the mouse thymocyte-proliferation assay. The patients' monocytes were defective in IL-1 production: the values were less than 1.0% of the control monocyte values (n = 12) and were in contrast with those of congenital neutropenia monocytes of 186.2% to 204.3%. These results demonstrate a familial monocyte disorder which is characteristic among the immunodeficiency syndromes with regard to the defective IL-1 production and the impaired phagocytic functions. 相似文献