全文获取类型
收费全文 | 6872篇 |
免费 | 357篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 126篇 |
妇产科学 | 50篇 |
基础医学 | 800篇 |
口腔科学 | 127篇 |
临床医学 | 463篇 |
内科学 | 2066篇 |
皮肤病学 | 66篇 |
神经病学 | 566篇 |
特种医学 | 157篇 |
外科学 | 1352篇 |
综合类 | 31篇 |
预防医学 | 157篇 |
眼科学 | 146篇 |
药学 | 447篇 |
中国医学 | 16篇 |
肿瘤学 | 662篇 |
出版年
2023年 | 37篇 |
2022年 | 55篇 |
2021年 | 90篇 |
2020年 | 64篇 |
2019年 | 76篇 |
2018年 | 79篇 |
2017年 | 85篇 |
2016年 | 105篇 |
2015年 | 125篇 |
2014年 | 137篇 |
2013年 | 158篇 |
2012年 | 304篇 |
2011年 | 388篇 |
2010年 | 229篇 |
2009年 | 219篇 |
2008年 | 348篇 |
2007年 | 348篇 |
2006年 | 404篇 |
2005年 | 396篇 |
2004年 | 379篇 |
2003年 | 352篇 |
2002年 | 381篇 |
2001年 | 261篇 |
2000年 | 241篇 |
1999年 | 198篇 |
1998年 | 93篇 |
1997年 | 76篇 |
1996年 | 73篇 |
1995年 | 59篇 |
1994年 | 43篇 |
1993年 | 47篇 |
1992年 | 103篇 |
1991年 | 112篇 |
1990年 | 79篇 |
1989年 | 104篇 |
1988年 | 98篇 |
1987年 | 100篇 |
1986年 | 100篇 |
1985年 | 82篇 |
1984年 | 48篇 |
1983年 | 65篇 |
1982年 | 36篇 |
1980年 | 37篇 |
1979年 | 58篇 |
1978年 | 33篇 |
1973年 | 33篇 |
1969年 | 29篇 |
1968年 | 35篇 |
1967年 | 31篇 |
1966年 | 32篇 |
排序方式: 共有7278条查询结果,搜索用时 15 毫秒
81.
82.
Gallbladder torsion: case report and review of 245 cases reported in the Japanese literature 总被引:4,自引:0,他引:4
Nakao A Matsuda T Funabiki S Mori T Koguchi K Iwado T Matsuda K Takakura N Isozaki H Tanaka N 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(4):418-421
We report here a case of torsion of the gallbladder in a 73-year-old woman. The patient was admitted to our hospital with
right hypochondralgia. Ultrasonography and computed tomography demonstrated a distended gallbladder, with a multilayered wall,
which contained no stones. Since the symptoms did not respond to antibiotics, laparotomy was performed. The gallbladder was
found to be twisted around its pedicle and to be gangrenous. Cholecystectomy was performed, and the patient had an uneventful
postoperative course. We also reviewed 245 cases reported in the Japanese literature. The clinical features of gallbladder
torsion, which include low frequency of fever and jaundice, poor response to antibiotic therapy, and acute onset of abdominal
pain, may be helpful in the differential diagnosis from acute cholecystitis. Moreover, a highly suggestive sign of gallbladder
torsion observed by ultrasonography or computed tomography is a markedly enlarged "floating" gallbladder with a continuous
hypoechoic line indicating edematous change in the wall.
Received for publication on Feb. 8, 1999; accepted on April 21, 1999 相似文献
83.
84.
85.
Long-term efficacy of immunization against hepatitis B virus in infants at high-risk analyzed by polymerase chain reaction. 总被引:1,自引:0,他引:1
H Kato K Nakata K Hamasaki D Hida H Ishikawa T Aritomi K Nakao Y Kato M Yano K Eguchi 《Vaccine》1999,18(7-8):581-587
Perinatal transmission of hepatitis B virus (HBV) is a common cause of chronic infection. In the present study, we evaluated the long-term efficacy of immunization against HBV in infants at high-risk, by using polymerase chain reaction (PCR). Two hundred and fifty-one infants received hepatitis B immunoglobulin at birth and a course of hepatitis B vaccine within 6 months of age between 1981 and 1993. Of 251 infants, 203 (81%) and 97 (39%) were followed until 1 and 4-6 years of age, respectively. HBV-DNA was detected by PCR in 74 (36%) of 203 children at 1 year of age, while the prevalence rate of children positive for HBV-DNA decreased to 14 (14%) of 97 children at 4-6 years of age, including 2 children who had the breakthrough variants of HBV. Our results indicate that most of HBV infections occur early, during the first year, and that immunization against HBV effectively protects infants at high-risk against viral transmission, at least up to 4-6 years of age. 相似文献
86.
M Wakakura K Mashimo S Oono Y Matsui A Tabuchi K Kani K Shikishima K Kawai Y Nakao Y Tazawa M Kiyosawa H Abe N Ohba K Yago S Maeda M Sugita S Ishikawa 《Japanese journal of ophthalmology》1999,43(2):133-138
BACKGROUND: A randomized, controlled clinical trial was conducted in 1991 to compare an intravenous megadose of methylprednisolone with a control drug (mecobalamin) for treating acute idiopathic optic neuritis. CASES: Sixty-six cases from 22 clinical centers throughout Japan were examined to evaluate the treatment on visual function parameters, such as visual acuity, visual field, color vision, contrast sensitivity, and critical flicker frequency. OBSERVATIONS: The methylprednisolone pulse treatment group showed faster recovery of visual function, particularly the visual acuity at 1 week (P<.05), Humphrey field analyzer mean deviation at 3 weeks (P<.05), and color vision at 1 week (P<.05). Recovery of contrast sensitivity at several different spatial frequencies was significant in the pulse treatment group at 1 (P<.01), 2 (P<.05), and 4 weeks (P<.05) after the start of treatment. Visual function test results at 12 weeks and 1 year were essentially the same in the two treatment groups. Side effects appeared more frequently in the pulse treatment group than in the control (P<.05). CONCLUSIONS: Pulse treatment does not appear effective for idiopathic optic neuritis even though visual function in the pulse treatment group of this trial recovered more quickly during the initial phase compared to the controls. More effective and specific treatment should be established for optic neuritis. 相似文献
87.
The antihypertensive effect of dipotassium (Z)-2-[[5-ethyl-3-[2'-(1H- tetrazol-5-yl)biphenyl-4-yl]methyl-1,3,4-thiadiazoline-2- ylidene]aminocarbonyl]-1-cyclopentenecarboxylate (CAS 169328-25-0, KRH-594), a new angiotensin II type 1 (AT1) receptor antagonist, was studied in several experimental hypertensive models. The effects of KRH-594 on the circulating reninangiotensin system and on renal function were also investigated. Oral administration of KRH-594 (0.3 or 1 mg/kg) dose-dependently inhibited the angiotensin II-induced pressor response in common marmosets. KRH-594 (1, 3, or 10 mg/kg p.o.) dose-dependently exerted a long-lasting antihypertensive effect in spontaneously hypertensive rats (SHRs) and in 2-kidney 1-clip renal hypertensive rats (RHRs). Furthermore, repeated oral administration of KRH-594 (3 or 10 mg/kg/d) reduced blood pressure dose-dependently in SHRs, RHRs, and renal hypertensive dogs without tachycardia and with no evidence of a rebound phenomenon following drug withdrawal. On the other hand, in deoxycorticosterone acetate salt rats and normotensive rats, KRH-594 (10 or 30 mg/kg p.o.) did not have significant effects on systolic blood pressure. In SHRs, KRH-594 (3 or 10 mg/kg/d p.o. for 2 weeks) dose-dependently increased both plasma renin activity and the plasma angiotensin I concentration, but had no effect on the urinary excretion of sodium, potassium, and chloride or on creatinine clearance. These results suggest that KRH-594 should be effective in patients with essential or renal hypertension. 相似文献
88.
Machiko Matsumoto Mitsuhiro Yoshioka Hiroko Togashi Toshiya Ikeda Hideya Saito 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(6):621-629
The functional regulation by dopamine (DA) receptors of serotonin (5-HT) release from the rat hippocampus was investigated by use of in vivo microdialysis. Dialysate 5-HT levels were reduced by co-perfusion of 10 M tetrodotoxin (TTX) and were elicited by K+ (60 and 120 mM) stimulation in a concentration-dependent manner. Local perfusion (10 M) and peripheral administration (20 mg/kg, i.p.) of fluoxetine produced increases in 5-HT levels. These results indicate that the spontaneous 5-HT levels in the rat hippocampus can be used as indices of neuronal origin from the serotonergic nerve terminals. The nonselective dopamine (DA) receptor agonist apomorphine (1, 10 and 100 M), when perfused through the probe over a period of 40 min, increased 5-HT release in a concentration-dependent manner. Apomorphine-induced (100 M) increases in 5-HT release was abolished by pretreatment with the selective D2 receptor antagonist, S(–)-sulphide (1 and 10 M), but not prevented by pretreatment with the selective D1 receptor antagonist, R(+)-SCH-23390 (R(+)-7-chloro-8-hydroxy-3-methyl-l-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine) (1 M). S(–)-Sulpiride and R(+)-SCH-23390 by themselves did not alter the spontaneous 5-HT levels. The 5-HT release was elevated by perfusion of the selective DA reuptake inhibitor GBR 12909 (1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-[3-phenylpropyl]piperazine)(1, 10 and 100 M), indicating the possibility of not only exogenous but also endogenous DA-mediated facilitatory effects on 5-HT release in vivo. The 5-HT release was also elevated by perfused (±)-PPHT ((±)-2-(N-phenylethyl-N-propyl)-amino-5-hydroxytetralin)(1, 10 and 100 M), the selective D2 receptor agonist, in a concentration-dependent manner. On the other hand, (±)-PPHT (100 M) failed to increase 5-HT release in catecholamine (CA)-lesioned rats pretreated with 6-hydroxydopamine (6-OHDA)(200 g/rat, i.c.v.). The (±)-PPHT-induced (100 M) increase in 5-HT release was prevented not only by pretreatment with 10 M S(–)-sulphide but also by pretreatment with the 2-adrenoceptor antagonist idazoxan (10 M). These findings suggest that the functional regulation of 5-HT release via D2 receptors exists in the rat hippocampus. Furthermore our results indicate that the facilitatory effect of 5-HT release via D2 receptors may be mediated indirectly by noradrenergic neurons, but not mediated directly through D2 receptors located on serotonergic nerve terminals. 相似文献
89.
I Nakao A Wakui T Hattori K Sugimachi T Saito 《Gan to kagaku ryoho. Cancer & chemotherapy》1991,18(8):1325-1332
A multi-institutional collaborative phase II study of (2"R)-4-O-tetrahydropyranyladriamycin (THP) was performed by intravenous administration to patients with advanced or recurrent gastric cancer. The administration schedules were (1) 40-60 mg/body every 3 or 4 weeks and (2) 20-40 mg/body once a week. Of 58 registered patients, 49 cases were eligible and 37 cases were evaluable for response. The therapeutic results were 1 CR, 4 PR, 14 NC and 18 PD. The response rate of the evaluable cases was 13.5%. The side effects were mainly bone marrow suppression and digestive symptoms. In particular, the frequency of leukopenia was a high 75.5%, while there was a decrease in hemoglobin in 38.8% and anorexia in 30.6%. The frequency and severity of alopecia, which is a known problem with anthracyclines, were slight, and no abnormal electrocardiograms were observed. 相似文献
90.
The efficacy of the McCoy laryngoscope, external laryngeal pressure, and their combination to improve the laryngoscopic view was evaluated in 219 patients and compared with the Macintosh laryngoscope. An experienced laryngoscopist performed laryngoscopy twice using the Macintosh laryngoscope and the McCoy laryngoscope in a random sequence, and external laryngeal pressure was applied in each laryngoscopy with the laryngoscopist's right hand. The laryngoscopic view obtained was graded on our modified Cormack's method. Without external laryngeal pressure, the McCoy laryngoscope provided a better laryngoscopic view than that obtained by the Macintosh laryngoscope (P < 0.001, signed rank test), but the view was worse than that with the Macintosh laryngoscope under external laryngeal pressure (P < 0.001). The McCoy laryngoscope combined with external laryngeal pressure provided a better view than the Macintosh laryngoscope with external laryngeal pressure (P < 0.001). 相似文献