全文获取类型
收费全文 | 3511篇 |
免费 | 212篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 155篇 |
儿科学 | 108篇 |
妇产科学 | 16篇 |
基础医学 | 451篇 |
口腔科学 | 121篇 |
临床医学 | 201篇 |
内科学 | 869篇 |
皮肤病学 | 18篇 |
神经病学 | 357篇 |
特种医学 | 194篇 |
外科学 | 471篇 |
综合类 | 15篇 |
预防医学 | 124篇 |
眼科学 | 47篇 |
药学 | 275篇 |
中国医学 | 4篇 |
肿瘤学 | 310篇 |
出版年
2023年 | 14篇 |
2022年 | 36篇 |
2021年 | 55篇 |
2020年 | 41篇 |
2019年 | 60篇 |
2018年 | 79篇 |
2017年 | 53篇 |
2016年 | 68篇 |
2015年 | 56篇 |
2014年 | 68篇 |
2013年 | 106篇 |
2012年 | 162篇 |
2011年 | 171篇 |
2010年 | 99篇 |
2009年 | 79篇 |
2008年 | 154篇 |
2007年 | 177篇 |
2006年 | 163篇 |
2005年 | 170篇 |
2004年 | 135篇 |
2003年 | 144篇 |
2002年 | 144篇 |
2001年 | 101篇 |
2000年 | 116篇 |
1999年 | 100篇 |
1998年 | 48篇 |
1997年 | 39篇 |
1996年 | 34篇 |
1995年 | 42篇 |
1994年 | 37篇 |
1993年 | 35篇 |
1992年 | 100篇 |
1991年 | 94篇 |
1990年 | 108篇 |
1989年 | 91篇 |
1988年 | 76篇 |
1987年 | 85篇 |
1986年 | 48篇 |
1985年 | 46篇 |
1984年 | 39篇 |
1983年 | 21篇 |
1982年 | 15篇 |
1981年 | 16篇 |
1980年 | 14篇 |
1979年 | 29篇 |
1978年 | 27篇 |
1977年 | 21篇 |
1970年 | 13篇 |
1969年 | 13篇 |
1968年 | 12篇 |
排序方式: 共有3736条查询结果,搜索用时 31 毫秒
11.
Kenji Tsukada Shigeru Kobayashi Tatsuya Gotoh Naoki Asakage Masayuki Sekine Morio Sasaki Eiji Miyazaki Takahisa Suzuki Toshio Yamada Shu Hirai Shigetaka Yamazaki 《Digestive endoscopy》2006,18(1):55-58
A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented. 相似文献
12.
M Yokoyama K Kawai F Shoji R Yanagisawa M Kanemura K Kitahara S Fujito 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(7):1031-1038
A total of 50 cases of primary tumors in the renal pelvis and ureter were treated in Tokyo University Branch Hospital (20 cases in 1966-1982) and in Tranomon Hospital (30 cases in 1977-1987). They were composed of 42 men and 8 women (5.3:1) with a mean age of 61 years. 31 patients suffered from renal pelvic tumors, 15 ureteral tumors and 4 tumors in both sites. The tumors were located in the left side in 33 cases, right in 16, and both sides in 1.86% of patients showed gross hematuria. The findings on IVP were filling defect (42%) and nonvisualization (33%). Positive urine cytology was obtained in 12 of 25 cases (48%). Surgery was performed in 47 cases. The remaining 3 cases were with advanced diseases. The surgeries were total nephroureterectomy plus ipsilateral retroperitoneal lymph node dissection in 26 cases, total nephroureterectomy without node dissection in 7, total nephroureterectomy and total cystectomy in 3, nephrectomy in 9, partial nephrectomy in 1 and segmental excision of ureter with ureteroureterostomy in one. Histologically, all tumors were transitional cell carcinoma. Over-all survival rates (Kaplan-Meier's method) of the operated patients at 1, 3, 5 years were 84.2%, 73.1% and 69.4%, respectively. The stage and grade of the tumors affected the prognosis. N factor at lymph node dissection was the most determining factor of prognosis. 3 advanced cases who did not receive surgery for primary site were treated with 5FU in 2, and with CAP in 1.2 of them died of the disease within 1 year after diagnosis, one patient was lost in follow up.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
13.
T Yamaga H Nakamura N Sugiyama Y Yoshino S Morio 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(6):462-466
We reported three cases of spontaneous rupture which were surgically treated with direct suture method. One patient was operated on within eight hours after rupture with good results. In two patients diagnoses were made more than two days after rupture. One had esophageal fistula, but completely recovered after cervical oesophageal fistula, and another died of multiple organ failure. In this syndrome, early diagnosis and surgical treatment are essential for acceptable results. For early diagnosis, we emphasized on the presence of roentgenologic mediastinal and cervical emphysema. In patients for whom diagnosis was delayed and post-operative leakage at the oesophageal suture line occurred, temporarily fistulation of the cervical oesophagus proved to be effective in exclusion and diversion of the ruptured segment. 相似文献
14.
Mitsuhiko Yanagisawa Rumiko Hosoki Masanori Otsuka 《European journal of pharmacology》1992,220(2-3):111-117
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM). 相似文献
15.
16.
Interaction of potassium channel openers and blockers in canine atrial muscle. 总被引:4,自引:4,他引:0
下载免费PDF全文
![点击此处可从《British journal of pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
1. The possibility that the interaction between potassium channel openers, e.g. cromakalim, pinacidil and nicorandil, and some potassium channel blockers involves a common site was investigated in canine atrial muscle. 2. Cromakalim, pinacidil and nicorandil produced a negative inotropic effect, their pD2 (-log EC50) values being 6.11 +/- 0.07, 5.37 +/- 0.09 and 4.55 +/- 0.07, respectively. 3. The potassium channel blockers, tetraethylammonium (TEA), tetrabutylammonium (TBA), 3,4-diaminopyridine (DAP), CsCl and BaCl2 all produced a positive inotropic effect. 4. The concentration-effect curves for the negative inotropic actions of pinacidil were shifted in a parallel way to the right by low concentrations of TEA, TBA or BaCl2. Maximum responses to pinacidil were depressed by higher concentrations of the blockers. An analysis of the non-competitive antagonism by TEA yielded pKA (-log KA) values of 4.00-4.05 for pinacidil. 5. The concentration-effect curves for cromakalim and nicorandil were shifted by TEA similarly to those for pinacidil, and a similar analysis yielded pKA values of 4.47-4.68 for cromakalim and 3.47-3.74 for nicorandil. 6. The KA values of cromakalim, pinacidil and nicorandil were about 10-30 times greater than their EC50 values, indicating that there are non-linear stimulus-effect relationships between the binding of the three potassium channel openers to their binding sites at potassium channels and their negative inotropic effects. 7. The dissociation constants for TEA could also be estimated from pA2 and pKB values for antagonizing competitively and non-competitively the negative inotropic effects of the three potassium channel openers; they were 3.47-3.89, and did not differ between the potassium channel openers. 8. The concentration-effect curves for the three potassium channel openers were not affected by DAP or CsCl. 9. These results suggest the following: (i) quaternary ammonium compounds like TEA and TBA antagonize the negative inotropic effect of cromakalim, pinacidil and nicorandil by binding to potassium channels, thus preventing binding of the channel openers to the same sites or closely related sites in canine right atrial muscles. 相似文献
17.
The effect of vitamin E on halothane-induced liver damage was studied in guinea pig halothane hepatitis. Twenty animals were divided into 3 groups, consisting of a control group, a halothane group and a vitamin E + halothane (H) group. The animals in the control group (n = 6) were allowed to inhale air only. The animals in the halothane group (n = 6) and the vitamin E + H group (n = 8) were allowed to inhale 1% halothane with air. Animals in the vitamin E + H group were additionally injected with 30 mg kg-1 of vitamin E 30 minutes prior to inhalation of halothane. Blood was aspirated from the heart immediately after sacrificing to measure the serum activity of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT). A microsomal suspension was prepared from the excised liver. Then the amount of thiobarbituric acid (TBA) reactive products in the microsomes were measured. The amount of tissue TBA-reactive products was increased by inhalation of halothane. The increase in the amount of TBA-reactive product was inhibited by the administration of vitamin E. The serum GPT activity was increased by halothane inhalation. Increased serum GOT and GPT activity were inhibited by the administration of vitamin E. These results demonstrated that vitamin E suppressed halothane-induced liver damage in the guinea pig by inhibiting lipid peroxidation. 相似文献
18.
T Yanagisawa 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1992,100(3):193-204
Since the existence of beta 3-adrenoceptors in various organs has been established, it is necessary to re-evaluate the subtypes of beta-adrenoceptors in cardiac muscle. We have demonstrated the possible existence of three subtypes of beta-adrenoceptors: beta 2-adrenoceptors, high-affinity beta 1-adrenoceptors (the so-called beta 1-adrenoceptors) and the low-affinity beta 1-adrenoceptors (akin to beta 3-adrenoceptors) in canine cardiac muscle, which are coupled with increases in myocardial cyclic AMP content and positive inotropic effects. Cyclic AMP generated by the activation of the high-affinity beta 1-adrenoceptors seems to be coupled with the positive inotropic effect much more effectively than via beta 2- or low-affinity beta 1-adrenoceptors. Stimulation of beta 2-adrenoceptors or the low affinity beta 1-adrenoceptor is causally related to the development of tolerance and to the adverse effects of nonselective beta-full agonists. It is conceivable that with denopamine, unlike with isoproterenol, tolerance can hardly develop, and there are no adverse effects resulting from its partial agonistic property and its selectivity for the high-affinity beta 1-adrenoceptors. The selective stimulation of the high-affinity beta 1-adrenoceptors would be beneficial for the management of mild congestive heart failure. In contrast, stimulation of the low-affinity beta 1-adrenoceptors by endogenous catecholamines or nonselective beta-agonists will contribute to deteriorating hemodynamic, symptomatic and prognostic consequences in patients with congestive heart failure. 相似文献
19.
Mitsuhiko Yanagisawa M.D. 《Pediatrics international》1987,29(6):815-823
Using spontaneously established autologous lymphoblastoid B cell lines (LCL), killer cell activities were studied in children with severe infectious mononucleosis (IM), chronic IM, and acute IM, and compared with those in EBV-seropositive normal controls. Natural killer (NK) cell activity of fresh peripheral blood mononuclear cells (PBMC) was normal in acute IM patients, but it was low in four of six patients with severe or chronic IM. Recombinant inter-leukin 2 (rIL-2)-activated PBMC from normal controls showed lymphokine-activated killer (LAK) cell activity against the respective autologous LCL. The levels of LCL lysis by LAK cells were significantly higher in acute IM patients, lower in chronic IM patients, and much lower in severe IM patients. In contrast to the fact that PBMC stimulated in vitro with autologous LCL (IVS cells) from normal controls and acute IM patients showed potent killing of autologous LCL, IVS cells from severe or chronic IM patients showed lower levels of LCL lysis, which were markedly augmented in three patients by rIL-2 addition to the cultures. These killer cell dysfunctions appear to be responsible for the severe or chronic course of EBV infection. 相似文献
20.
Kuroiwa K Li H Tago K Iwahana H Yanagisawa K Komatsu N Oshikawa K Sugiyama Y Arai T Tominaga SI 《Hybridoma》2000,19(2):151-159
The human ST2 gene can be specifically induced by growth stimulation in fibroblastic cells, and can also be induced by antigen stimulation in Th2 cells. The gene encodes a soluble secreted protein, ST2, and a transmembrane protein, ST2L, which are closely related to the interleukin-1 receptor. To gain insight into the biological roles of the ST2 gene, three monoclonal antibodies (MAbs) against human ST2 gene products were obtained. To obtain these antibodies, immunization was carried out using two different immunogens: purified soluble human ST2 protein (hST2), and COS7 cells, which express the extracellular portion of human ST2L. 2A5 and FB9 MAbs were derived from the immunization with soluble hST2, and HB12 was derived from the COS7 cell immunization. All three antibodies were shown to detect native forms of the human ST2 gene products by immunoprecipitation, flow cytometry, and enzyme-linked immunosorbent assay (ELISA). In the competitive ELISA using biotinylated and nonlabelled MAbs, neither FB9 nor HB12 affected the binding of 2A5 to ST2 gene products. Based on this result, we constructed a sandwich ELISA system using 2A5 and FB9 to measure the concentration of soluble hST2 in sera. The ELISA, combined with the flow cytometry using these antibodies, will be a useful tool for elucidating the functions of human ST2 gene products in individuals. 相似文献