全文获取类型
收费全文 | 16332篇 |
免费 | 870篇 |
国内免费 | 92篇 |
学科分类
医药卫生 | 17294篇 |
出版年
2023年 | 72篇 |
2022年 | 84篇 |
2021年 | 362篇 |
2020年 | 183篇 |
2019年 | 227篇 |
2018年 | 321篇 |
2017年 | 276篇 |
2016年 | 328篇 |
2015年 | 313篇 |
2014年 | 428篇 |
2013年 | 560篇 |
2012年 | 760篇 |
2011年 | 916篇 |
2010年 | 512篇 |
2009年 | 462篇 |
2008年 | 759篇 |
2007年 | 865篇 |
2006年 | 823篇 |
2005年 | 851篇 |
2004年 | 772篇 |
2003年 | 736篇 |
2002年 | 779篇 |
2001年 | 462篇 |
2000年 | 468篇 |
1999年 | 453篇 |
1998年 | 194篇 |
1997年 | 160篇 |
1996年 | 142篇 |
1995年 | 114篇 |
1994年 | 126篇 |
1993年 | 101篇 |
1992年 | 366篇 |
1991年 | 327篇 |
1990年 | 324篇 |
1989年 | 307篇 |
1988年 | 295篇 |
1987年 | 293篇 |
1986年 | 289篇 |
1985年 | 221篇 |
1984年 | 152篇 |
1983年 | 148篇 |
1982年 | 56篇 |
1981年 | 64篇 |
1979年 | 122篇 |
1978年 | 58篇 |
1977年 | 60篇 |
1974年 | 52篇 |
1973年 | 60篇 |
1972年 | 66篇 |
1970年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Noboru Sakai Noriko Nishizawa Jun-ichi Matsushima Hideo Kurihara Takehiko Kokubun Ken-ichi Koichi Shiroh Maguchi Yukio Inuyama 《Artificial organs》1996,20(8):951-954
Abstract: To prevent side effects from a silicone shim in Isshiki thyroplasty type I, we used a ceramic shim in 10 patients with unilateral recurrent laryngeal nerve paralysis. No published reports have described the use of ceramic in this type of surgery. According to the degree of glottic insufficiency, ceramic shims of various heights were inserted into the fenestration made in the thyroid ala. All patients experienced subjective improvement of voice postoperatively. Laryngoscopies in most cases showed that glottic insufficiency improved postoperatively. In the postoperative examination, the maximum phonation time improved an average of 3.7 s, and the mean flow rate improved an average of 331 ml/s. We have analyzed the relationship of these improvements to the degree of glottic insufficiency and have compared our results with those of other investigators. 相似文献
103.
104.
The effects of lung volume and respiratory airflow on airway resistance were studied in five anesthetized and paralyzed patients. Airway resistance measured during the inspiratory phase with intermittent constant airflow inflatoins decreased in inverse correlationship to increases in lung volume. Airway resistance measured during the expiratory phase with an airway interruption technique, on the other hand, increased with a linear relationship to the expiratory airflow as expressed by a function of Y = K1 + K2X. K1, calculated from the values of airway resistance corresponding to three different airflows, was unaffected by intentional expiratory resistance loading. Thus, simultaneously with the measurement of airway resistance by this method, expiratory gas sampling with a Douglas bag can be done if necessary. Since the K2 value of the endotracheal tube used in this study (Portex® I.D. 8mm, length 26cm) was quite high (5.0cmH2O·1–2·sec2), depending on the airflow, the presence of the endotracheal tube strongly affected the measurement of airway resistance during general anesthesia. K1 measured by the above method, however, may be considered as the best way to evaluate the lower airway resistance independent of either lung volume or expiratory airflow.(Sakai T, Yoshida H, Yano H et al.: Measurement of airway resistance in anesthetized and paralyzed subjects: proposal for evaluation of K1 values. J Anesth 2: 139–145, 1988) 相似文献
105.
T Kitade Y Odahara S Shinohara T Ikeuchi T Sakai K Morikawa M Minamikawa S Toyota A Kawachi M Hyodo 《Acupuncture & electro-therapeutics research》1988,13(2-3):87-97
It has been claimed that the mechanism of acupuncture analgesia can be explained in part by endogenous opioids. If so, it might be possible to enhance the analgesic effect of acupuncture by the administration of endorphins. If D-phenylalanine (DPA), an inhibitor of the endorphin degrading enzyme, is administered, the analgesic effect of acupuncture should be prolonged due to the increased level of endorphins. From the changes of the pain threshold (PT), we investigated whether or not the pre-administration of DPA can enhance the analgesic effect of acupuncture in humans. In addition, we examined the inhibitory effect of naloxone. 1) In all five subjects whose PT was raised after acupuncture anesthesia (respondents), the rise in PT was significantly prolonged by DPA. 2) Out of 10 subjects whose PT remained almost unchanged after acupuncture anesthesia (non-respondents), the PT was increased by DPA in 5 cases. 3) The rise in PT was most prominent when DPA was administered 30 minutes before the start of acupuncture anesthesia. 4) In all 4 respondents in whom the rise in PT persisted after DPA and acupuncture anesthesia, their raised PT dropped after the intravenous injection of naloxone (10 mg). 5) These findings show that DPA enhances the analgesic effect of acupuncture by the "endorphin mechanism." 相似文献
106.
Two patients with "my hand" sign in association with tactile extinction from callosal lesion, one due to left anterior cerebral artery occlusion, the other due to right anterior cerebral artery aneurysm rupture, were reported. The examination of "my hand" sign was performed with the methods proposed by Brion et al. Our patients correctly responded when they grasped their own or the examiner's thumb with their left hand. But they replied "my finger"when they grasped not only their own but also the examiner's thumb with their right hand. Left tactile extinction was observed after a routine extinction test in one patient, and it was observed in the other after the following method: both patient's index fingers were disposed in his midline position. In these methods of extinction test, they made errors in saying "right" when both fingers were touched simultaneously. However, they said "both" when their right index finger alone was touched (synchiria) during an extinction test using the following method: both index fingers of patients were approached by examiner to touch each other or for one of them to touch the examiner's finger. When they were asked whose finger they touched in this method (whose finger test), they made the same errors as seen in "my hand" sign test. These test results suggest that there is a common underlying mechanism in the "my hand" sign and extinction, because the sense of double stimulations felt when only one stimulation is given (synchiria), is a possible explanation for the "my hand" sign and the pathogenesis of synchiria appears to be related to extinction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
Long-term effect of urokinase therapy in IgA nephropathy 总被引:4,自引:0,他引:4
Effects of urokinase (UK) therapy in patients with moderate to advanced degrees of IgA nephropathy (IgAN) were examined. Twenty-seven patients were treated by "two weeks" UK administration, 14 patients were treated by "consecutive" UK administration and 16 patients were treated by antiplatelet drugs. There were marked improvements in urinary protein concentration, serum creatinine and blood urea nitrogen after UK therapy, especially in patients treated by "consecutive" UK administration which was performed by "single shot" UK injection. Clinical prognosis was favorable in patients treated by UK administration compared with those given antiplatelet treatment. It was concluded that "consecutive" UK administration might be useful for treatment of IgAN with moderate to advanced renal injuries. 相似文献
108.
Clinical study on intracranial arachnoid cyst: with reference to the middle cranial fossa 总被引:2,自引:0,他引:2
N Sakai M Kumagai T Ueda M Iwamura Y Nishimura Y Miwa K Shimizu T Hirata T Andoh H Yamada 《No shinkei geka. Neurological surgery》1989,17(2):117-123
Thirty-two cases of congenital arachnoid cyst (AC), 26 cases of supratentorial, and 6 cases of infratentorial cyst are reported. They were encountered over a period of 9 years. The 26 supratentorial cysts consisted of 21 cases located in the middle fossa, 2 in the frontal, and 3 in the suprasellar. Patients' ages ranged from 7 months to 67 years (mean: 19.3 years), with a male to female ratio of 23:9. The most common symptoms were headache, epileptic seizure, and cranial enlargement. Based on observations between neuroradiological examinations including analysis of the cyst content, and operation, typical AC might be defined as "duplicated arachnoid and its splitting", and it may be said that "there is continuous existence of cerebral structure such as cortex and white matter lying adjacent to AC on MRI". Out of 32 cases, 15 received surgical treatment because of mass effect of AC itself, abnormal dynamics of the AC fluid, and/or increasing sign of ICP. 13 cases had resection of AC outer membrane with craniotomy, and the remaining two had cystoperitoneal shunt. One of the shunting cases complicated subdural hematoma. Surgical treatment was discussed and radical craniotomy rather than a shunt procedure was preferred. Prognosis of all cases was favorable and uneventful. 相似文献
109.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes. 相似文献
110.
Tsuchida E Komatsu T Matsukawa Y Nakagawa A Sakai H Kobayashi K Suematsu M 《Journal of biomedical materials research. Part A》2003,64(2):257-261
The administration of extracellular, hemoglobin-based oxygen carriers often elicits an acute increase in blood pressure by vasoconstriction. This side effect is now recognized to be due to the depletion of nitric oxide (endothelial-derived relaxing factor) by the extravasuated hemoglobins. We have recently found that the administration of a recombinant human serum albumin (rHSA)-based oxygen carrier involving synthetic tetraphenyporphinatoiron(II) derivative (FeP) (rHSA-FeP) does not induce such hypertensive action, because of its low permeability through the vascular endothelium. The heart rate responses after the rHSA-FeP injection were also negligibly small. Visualization of the intestinal microcirculatory changes clearly revealed the widths of the venule and arteriole to be fairly constant. The entirely synthetic rHSA-FeP becomes a promising material as a new type of red blood cell substitute. 相似文献