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51.
Hata T; Aoki S; Manabe A; Hata K; Miyazaki K 《Human reproduction (Oxford, England)》1997,12(8):1800-1804
Our purpose was to visualize normal embryonal and fetal surface anatomical
structures in the first trimester of human pregnancy by use of
three-dimensional ultrasonography with a specially developed abdominal
three-dimensional transducer. Four embryos and 31 fetuses of 8-13 weeks
gestation were studied with a specially-developed abdominal
three-dimensional transducer (3.5 MHz). This imaging system can provide
conventional two-dimensional ultrasonography images and can also generate,
within seconds, high-quality three-dimensional images in the surface and
transparent mode with no need for an external workstation. The percentage
of surface anatomical structures visualized at each gestational age
interval using two-dimensional and three-dimensional ultrasonography is
presented. Head and trunk were depicted in all cases. The number and the
clarity of visualization of face, upper and lower extremities, hand, and
foot increased with advancing gestation. The free loop of the umbilical
cord was depicted in most cases. The number of depictions of abdominal cord
insertion, midgut herniation, and yolk sac decreased with the increase of
gestation. Genitals could not be identified in the first trimester. The
ability to view some surface anatomical structures (face, hand, and foot)
was better with three-dimensional ultrasonography than with two-dimensional
ultrasonography. Three-dimensional ultrasonography provides a novel means
for visualization of surface anatomical structures of the embryo and early
fetus. These results suggest that three-dimensional ultrasonography can
become an important modality in future embryological and early fetal
research and in detection of embryonic and fetal developmental disorders in
the first trimester of pregnancy.
相似文献
52.
Common origin of the Val30Met mutation responsible for the amyloidogenic transthyretin type of familial amyloidotic polyneuropathy 总被引:3,自引:0,他引:3
53.
Association of aortic atherosclerosis with cerebral beta-amyloidosis and learning deficits in a mouse model of Alzheimer's disease 总被引:2,自引:0,他引:2 下载免费PDF全文
High fat/high cholesterol diets exacerbate beta-amyloidosis in mouse models of Alzheimer's disease (AD). It has been impossible, however, to study the relationship between atherosclerosis and beta-amyloidosis in those models because such mice were on atherosclerosis-resistant genetic backgrounds. Here we report the establishment of AD model mice, B6Tg2576, that are prone to atherosclerosis. B6Tg2576 mice were produced by back-crossing Tg2576 mice, an AD mouse model overexpressing human amyloid beta-protein precursor with the Swedish double mutation, to C57BL/6 mice, a strain susceptible to diet-induced atherosclerosis. An atherogenic diet induced aortic atherosclerosis and exacerbated cerebral beta-amyloidosis in B6Tg2576 mice. Compared with age-matched non-transgenic littermates, B6Tg2576 mice developed significantly more diet-induced aortic atherosclerosis. Unexpectedly, normal diet-fed B6Tg2576 mice also developed fatty streak lesions (early atherosclerosis) in the aorta. The aortic atherosclerotic lesion area positively correlated with cerebral beta-amyloid deposits in B6Tg2576 mice on both atherogenic and normal diets. Furthermore, behavioral assessments demonstrated that B6Tg2576 mice fed an atherogenic diet had more spatial learning impairment than those fed a normal diet. Our results suggest that synergistic mechanisms may be involved in the pathogenesis of atherosclerosis and AD. These findings may have important implications in the prevention and treatment of cardiovascular diseases as well as AD. 相似文献
54.
T. Kubo M. Kihara H. Hata Y. Misu 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(3):274-277
Summary The cardiovascular effects of selective alpha1 and alpha2 agonists and antagonists injected into the nucleus tractus solitarii (NTS) were studied in urethane-anesthetized rats. Methoxamine (0.3–3 g) injected bilaterally into the NTS caused a dose-dependent increase in blood pressure and heart rate. Phenylephrine (6 g) and an imidazolidine derivative St 587 (3 g) similarly injected also produced an increase in blood pressure, whereas a-methylnoradrenaline and an azepine derivative B-HT 920 (1 and 3 g) caused a decrease in blood pressure and heart rate. The pressor response to methoxamine (1 g) was markedly inhibited by prazosin (0.3 pg) injected into the same sites or hexamethionum (25 mg/kg, i. v.). Prazosin (0.3 g) alone injected bilaterally into the NTS did not affect the blood pressure, while yohimbine (0.1 g) similarly injected increased the pressure. These results suggest that in the rat NTS there exist alpha1 adrenoceptors responsible for an increase in arterial pressure. The NTS alpha2 adrenoceptors seem to be involved in the tonic regulation of arterial pressure.
Send offprint requests to T. Kubo at the above address 相似文献
55.
Conclusion Nous pensons que nous devons clairement préciser non seulement la distribution des branches de la v. porte, mais aussi celle des v. hépatiques drainant une tumeur afin de faciliter au mieux la résection hépatique à réaliser tout en conservant un maximum de parenchyme fonctionnel. Lorsqu'un segment doit être réséqué, il est nécessaire d'étudier la morphologie des veines et de leurs branches par phlébographie hépatique préopératoire afin de bien préciser les limites de la résection en fonction du siège de la tumeur. 相似文献
56.
Vascular anatomy of the pancreaticoduodenal region: A review 总被引:4,自引:0,他引:4
G. Murakami K. Hirata T. Takamuro M. Mukaiya F. Hata S. Kitagawa 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(1):55-68
Vascular anatomy of the pancreaticoduodenal region has been the subject of numerous studies. However, several essential areas
of confusion remain in interpretation of the vascular configuration. We note and discuss three key points in relation to this
confusion: (1) a missing vascular arcade, (2) a rearrangement of the arcade by collateral and/or transverse vessels, and (3)
a solitary vessel without an accompanying comites vein or artery. In addition, we consider that different interpretations
as well as varying reported incidences depend on different "thresholds" when observations are made. Consideration of new aspects
of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. In terms
of the selection of lymph node resection procedure, we discuss mainly the inferior arterial origin. Special attention should
be paid to the ligation of inferior arteries because of the high incidence of the common trunk formation of the upper jejunal
and inferior pancreaticoduodenal arteries. With regard to duodenum-preserving pancreatic head resection for benign tumors,
our observations are introduced in view of either arterial or venous configuration. First, a communicating artery between
the anterior and posterior arterial arcades is noted because of its possible critical role in blood supply to the papilla
of Vater. Second, a venous drainage route from the duodenum to the retroperitoneal space in "normal" specimens is described.
Received for publication on June 17, 1998; accepted on July 27, 1998 相似文献
57.
Sezai A Shiono M Orime Y Nakata K Hata M Iida M Kashiwazaki S Kinoshita J Nemoto M Koujima T Furuichi M Eda K Hirose H Yoshino T Saitoh A Taniguchi Y Sezai Y 《Artificial organs》1999,23(3):280-285
We examined a major organ function during 3 h biventricular assisted circulation after acute myocardial infarction model in the pig. In left ventricular circulation, the outflow cannula was placed in the ascending aorta and an inflow cannula through the mitral valve in the left ventricle. A pump (pulsatile group, Zeon Medical, Inc., Tokyo, Japan and nonpulsatile group, Nikkiso HPM-15, Nikkiso, Inc., Tokyo, Japan) was connected to each cannula. In right ventricular circulation, the outflow cannula was placed in the pulmonary artery and an inflow cannula in the right ventricle. The right ventricular circulation was supported by a nonpulsatile pump (Nikkiso HPM-15). The items measured were the regional blood flows of the cortex and medulla in the kidney, white matter and gray mater in brain, and liver; renal arterial flow; carotid arterial flow; portal vein flow; common hepatic arterial flow; arterial ketone body ratio (AKBR); and lactate/pyrubic acid (L/P). In the pulsatile group, the renal cortical blood flow increased, and the medulla blood flow decreased. On the other hand, in the nonpulsatile group, both regional blood flows decreased. That means that in the pulsatile assisted group intrarenal redistribution improved rather than in the nonpulsatile assisted group. In addition the liver regional blood flow, AKBR, and L/P showed significant differences between the pulsatile and nonpulsatile groups. On the other hand, the white matter and gray matter regional blood flows and carotid arterial flow did not show significant differences between the groups. The results of our study indicated that pulsatile circulation produced superior circulation in the kidney and liver, and microcirculation on the cell level was superior as well in early treatment of acute heart failure. 相似文献
58.
Full-thickness skin graft from the ulnar aspect of the wrist to cover defects on the hand and digits
Skin defects on the volar surface of the hand and digits are commonly treated with skin grafts. Many donor sites capable of providing adequate skin have already been reported. Ideal conditions for the donor site depend on skin color, texture, durability, and size. The authors describe the use of a new donor site for harvesting skin grafts to repair relatively small skin defects on the hand and digits. They used full-thickness skin grafts from the ulnar aspect of the wrist to reconstruct burn contractures and syndactyly in 20 patients. Their grafts provided an ideal color and texture match, and normal function of the hand and digits was restored. The donor site was closed directly, and the resulting scar was inconspicuous. 相似文献
59.
J. Y. Lew F. Hata T. Ohashi M. Goldstein 《Journal of neural transmission (Vienna, Austria : 1996)》1977,41(2-3):109-121
Summary Bromocriptine and lergotrile, which are clinically used as antiparkinsonian (AP) agents, compete for the binding of H3-dopamine, H3-apomorphine, and H3-haloperidol to striatal membrane sites. Lergotrile has a higher affinity for the H3-dopamine binding to bovine striatal membranes than bromocriptine. Lergotrile and bromocriptine are almost equipotent in competing for the binding of H3-apomorphine to rat striatal membranes, but bromocriptine is more potent in competing for the binding of H3-haloperidol than lergotrile. These results indicate that lergotrile and bromocriptine are mixed putative agonist-antagonist with respect to the postsynaptic dopamine receptors. Lergotrile and bromcriptine at higher concentrations inhibit synaptosomal tyrosine hydroxylase activity, and reverse the apomorphine elicited enzyme inhibition. Thus, these ergot alkaloids behave as mixed agonist-antagonist also with respect to the presynaptic dopamine receptors. Bromocriptine and lergotrile, as well as other tested DH-ergot alkaloids and neuroleptics, compete for the binding of the-antagonist H3-WB-4101 to rat cerebral cortical membranes. The displacing potencies of the tested DH-ergot alkaloids and of the neuroleptics indicate that they have a high affinity for the-adrenoreceptors in the CNS. 相似文献
60.
Taro Semba Yasuhiro Funahashi Naoto Ono Yuji Yamamoto Naoko Hata Sugi Makoto Asada Kentaro Yoshimatsu Toshiaki Wakabayashi 《Clinical cancer research》2004,10(4):1430-1438
We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820. 相似文献