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101.
Decreased blood flow at neuroretinal rim of optic nerve head corresponds with visual field deficit in eyes with normal tension glaucoma 总被引:2,自引:0,他引:2
Enrique Adan Sato Yuichiro Ohtake Kei Shinoda Yukihiko Mashima Itaru Kimura 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(7):795-801
PURPOSE: To determine the relationship between the blood flow parameters of the optic disc rim and the glaucomatous visual field changes. DESIGN: Observational cross-sectional study. METHODS: Tissue blood flow in the neuroretinal rim within the optic disc was determined with the Heidelberg retina flowmeter(HRF) in 54 eyes of 54 patients with normal tension glaucoma (NTG). Patients were selected whose visual field defects were confined to either the superior or inferior hemifield. Blood flow measurements were made in a 10 degrees x 2.5 degrees area of the superior and inferior neuroretinal rim within the optic disc. The mean blood flow (MBF) was calculated by the automatic full-field perfusion image analyzer program, and the ratio of the MBF in the superior to the inferior rim areas (the S/I ratio) was calculated from the same HRF image in order to minimize the variation of measurement condition. RESULTS: Inferior rim blood flow is less than superior rim blood flow in patients with superior hemifield defect, and superior rim blood flow is reduced compared to inferior in patients with inferior hemifield defect. The mean S/I ratios of the MBF in the patients with superior hemifield defect (1.46, n=37) was significantly higher than that in the patients with inferior hemifield defect (0.79, n=17; P<0.0001, Mann-Whitney U-test). CONCLUSIONS: The blood flow in the neuroretinal rim was found to correspond to the regional visual field defect in eyes with NTG. Reductions in flow were associated with reductions in function. 相似文献
102.
Michihiro Mutoh Kouji Watanabe Tomohiro Kitamura Yutaka Shoji Mami Takahashi Toshihiko Kawamori Kousuke Tani Michiyoshi Kobayashi Takayuki Maruyama Kaoru Kobayashi Shuichi Ohuchida Yukihiko Sugimoto Shuh Narumiya Takashi Sugimura Keiji Wakabayashi 《Cancer research》2002,62(1):28-32
Accumulating evidence indicates that overproduction of prostanoids attributable to overexpression of cyclooxygenase-2 (COX-2) plays an important role in colon carcinogenesis. We have shown recently that the prostaglandin (PG) E receptor, EP(1), but not EP(3), is involved in mouse colon carcinogenesis. In line with our previous study, here we examined the role of prostanoid receptors in colon carcinogenesis using six additional lines of knockout mice deficient in prostanoid receptors EP(2), EP(4), DP, FP, IP, or TP. The animals were treated with the colon carcinogen, azoxymethane (AOM), and examined for the development of aberrant crypt foci (ACFs), putative preneoplastic lesions in the colon. Formation of ACFs was decreased only in the EP(4)-knockout mice, to 56% of the wild-type level. To confirm these results, we also examined the inhibitory effects of an EP(4)-selective antagonist, ONO-AE2-227, in the diet on the formation of AOM-induced colon ACFs in C57BL/6Cr mice and on the development of intestinal polyps in Min mice. ONO-AE2-227 at a dose of 400 ppm reduced the formation of ACFs to 67% of the control level, and intestinal polyp numbers in Min mice receiving 300 ppm were decreased to 69% of the control level. Plating efficiency assays showed that addition of 1.0 microM ONO-AE1-329, an EP(4)-selective agonist, resulted in a 1.8-fold increase in the colony number of the human colon cancer cell line, HCA-7, similar to the effect of PGE(2). Moreover, EP(4) mRNA expression was clearly observed in normal colon mucosa and colon tumors in mice. Our previous and present results indicate that PGE(2) contributes to colon carcinogenesis through its actions mediated through EP(1) and EP(4) receptors; therefore, antagonists for these two receptors may be good candidates as chemopreventive agents against colon cancer. 相似文献
103.
Discrete regions in the laterodorsal tegmental area of the rat regulating the urinary bladder and external urethral sphincter 总被引:1,自引:0,他引:1
In urethane anesthetized rats, the laterodorsal tegmental area was stimulated systematically with a carbon fiber electrode to clarify regions regulating the urinary bladder and/or the external urethral sphincter. Contraction of the former was monitored by bladder pressure and that of the latter by electromyogram. Stimulation of a small area around the ventrolateral edge of the central gray in a plane at the junction of the mesencephalon and pons, where cholinergic neurons in the laterodorsal tegmental nucleus formed the largest mass, induced contraction only of the bladder. Arranged in tandem rostrocaudally with this bladder site, a very small area whose stimulation induced contraction only of the sphincter was found also at the ventrolateral edge of the central gray in a plane slightly caudal to the above. Slightly lateral and caudal to this sphincter site, there were sites the stimulation of which induced contraction of both the bladder and sphincter. It was thus shown physiologically that there were discrete sites in the laterodorsal tegmental area regulating the bladder and sphincter independently. 相似文献
104.
105.
Mitsuru Suzuki Shingo Yamane Takao Matsugane Takuo Nobuto Nakanobu Azuma Toshio Nishideu Masaki Shinomiyat† Kou Saito† Norihiro Sasakind‡ Yukihiko Nose§ 《Artificial organs》1996,20(4):296-302
Abstract: A comparative assessment has been made regarding efficacy and safety of the double filtration plasmapheresis (DFPP), thermofiltration (TFPP), and low–density lipoprotein (LDL) adsorptive (PA) methods by making a crossover test on heterozygous familial hypercholesterolemia patients. Treatments by DFPP, TFPP (secondary membrane Evalux 5A), and PA (Liposorber LA–40) were carried out 5 times each, with a 2–week interval, in 5 patients with heterozygous familial hypercholesterolemia. The same plasma separator (Plasmacure PS–60, polysulfone) was used in all cases, and the volume of plasma processed was set at 4 L. High removal rates were obtained of total cholesterol, LDL cholesterol, triglycerides TG, and apolipoprotein B (apoB) by all three methods, and no differences were observed. Lipoprotein (a), apoA–2, apoC–3, fibrinogen, and immunoglobulin M (IgM) showed significantly high removal rates by the DFPP and TFPP methods compared with the PA method.
The sieving coefficient of albumin and high–density lipoprotein (HDL) cholesterol at 2 and 4 L of plasma processed exhibited high permeabilities using all three methods. Supplementing albumin was not necessary. An increase of the transmembrane pressure was observed in 1 case treated by DFPP but was not observed when using the TFPP or PA method. No changes were observed in serum interleukin 1β (IL–lβ) or tumor necrosis factor–a (TNF–α) before and after treatment by any of the three methods. No remarkable side effects were observed using either the DFPP or TFPP method. The DFPP and TFPP methods showed efficacy and safety that was not inferior to the PA method in conventional LDL apheresis, and the dead–end method of the filter operation without the discarding of plasma was shown to be possible. 相似文献
The sieving coefficient of albumin and high–density lipoprotein (HDL) cholesterol at 2 and 4 L of plasma processed exhibited high permeabilities using all three methods. Supplementing albumin was not necessary. An increase of the transmembrane pressure was observed in 1 case treated by DFPP but was not observed when using the TFPP or PA method. No changes were observed in serum interleukin 1β (IL–lβ) or tumor necrosis factor–a (TNF–α) before and after treatment by any of the three methods. No remarkable side effects were observed using either the DFPP or TFPP method. The DFPP and TFPP methods showed efficacy and safety that was not inferior to the PA method in conventional LDL apheresis, and the dead–end method of the filter operation without the discarding of plasma was shown to be possible. 相似文献
106.
107.
Abstract For many years, it was thought that nonpulsatile perfusion produced physiological and circulatory abnormalities. Since 1977, Yukihiko Nosé and his colleagues have challenged this misconception. Toward that end, they did show that if a 20% higher blood flow uses more than that required for a pulsatile blood pump, then there would be no circulatory or physiological abnormalities. These experimental findings confirm that there is no difference in clinical outcome using either a pulsatile or nonpulsatile blood pump. Furthermore, the nonpulsatile rotary blood pump demonstrates efficient and reliable performance in various clinical situations. The nonpulsatile blood pump is a simple and reliable design that is manufactured easily and that has several desirable features. There is no need to incorporate heart valves, which are the most thrombogenic and blood trauma-inducing component. A continuous flow pump does not require a large orifice inflow conduit and proves to be easier to implant in patients with minimal damage to the myocardium. There is no need to incorporate a compliance volume-shifting device, which is essential for a pulsatile blood pump. The nonpulsatile device is a continuous blood pumping system; therefore, the control system is simpler and more reliable than that of a pulsatile pump. Because of the rotary blood pump's structure, only one moving part is necessary for the blood-pumping motion. By using durable components for this moving part, a durable system becomes possible. Because the electrical motor operates continuously, the on-and-off motion required for a pulsatile pump is not necessary; therefore, it is a more efficient and durable system. Thus, this group is working on the development of a nonpulsatile blood pump as a permanently implantable assist device. To achieve this goal, it is necessary to incorporate seven features into the system: small size, atraumatic features, antithrombogenic features, antiinfection features, a simple and durable design, and low energy requirement with easy controllability. 相似文献
108.
Masahiro Noguchi Masue Muto Hirofumi Yanagidaira Setsu Sato Motonobu Ozaki Masahiko Katayama Yukihiko Naruki Sachio Otsuka 《Annals of nuclear medicine》1995,9(1):39-42
We encountered a very rare case of an intra-atrial tumor thrombus from hepatocellular carcinoma (HCC). Conventional XCT and US gave evidence of HCC. In nuclear medicine studies performed incidentally, the first study with99mTc-phytate liver scintigraphy showed 2 SOLs and evidence of chronic liver disease, and the second study with67Ga-citrate scintigraphy demonstrated 2 hot lesions within the liver parenchyma, and also another unexpected hot area just above the left lobe of the liver, seemingly beyond the diaphragm. When echocardiography was performed, in addition to ECG, because the patient began to complain of dyspnea, an oblong mass lesion was detected within the right atrium. Reexamination with XCT and angiography clearly proved the existence of an intraatrial tumor thrombus. These results indicate the need for routine examination by echocardiography for HCC patients complaining of dyspnea. 相似文献
109.
A dose of 50 mg of chlorpromazine (CPZ) was given to 6 untreated schizophrenic patients and 8 healthy volunteers at 7:00 a.m. before breakfast. Blood samples were taken 3, 6, 9 and 24 hrs after for the analyses of CPZ and its metabolites by gas chromatographic techniques. In the cases of schizophrenic patients, the CPZ treatment was continued. Serum drug levels were monitored and clinical response assessed. The drug levels in serum of another group of patients already under long term treatment were also determined. Although wide inter-patients variations in serum drug levels after a single dose administration were observed, the CPZ level in the patients decreased faster than in the normal subjects. Patients showing high levels of the metabolites such as demethylated CPZ and CPZ sulfoxide after a single dose of CPZ tended to achieve poorer clinical improvement in CPZ therapy, agreeing with the results that poor responders to long term CPZ treatment revealed relatively high levels of the metabolites of CPZ compared with CPZ level. The results indicate that the study of a single dose administration prior to initiating treatment with CPZ can be used to determine how an individual patient would respond to CPZ therapy and be a valuable tool in the rational pharmacotherapy of schizophrenic patients. 相似文献
110.
Haruo Nagayama Akinori Takagi Yukihiko Sakurai Kenzaburo Nishiwaki Ryo Takahashi 《Psychopharmacology》1978,58(1):49-53
In order to study differences in the effect of the neuroleptics due to time of administration, rats were administered chlorpromazine (CPZ) in a variety of combinations of dose and time and the sedation period was measured. There was daily fluctuation in the sedative effect and the pattern of fluctuation differed according to dosage. A similar study under the condition of reversed light and dark gave a reversed curve of the daily fluctuation, showing that the rhythm of light and dark controls the fluctuation externally. In an attempt to elucidate the mechanism of these phenomena, CPZ was administered at two different times, between which there was a significant difference in the sedation period, and time-course changes in plasma and brain concentration of the drug and its metabolites were measured. No difference was found. These results are interpreted as indicating that the phenomena could arise at the level of amine-receptor activity in the brain. In addition, daily fluctuation due to time of administration was noted in lethality. 相似文献