首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   23927篇
  免费   1932篇
  国内免费   1131篇
耳鼻咽喉   239篇
儿科学   126篇
妇产科学   470篇
基础医学   812篇
口腔科学   170篇
临床医学   2111篇
内科学   1513篇
皮肤病学   234篇
神经病学   533篇
特种医学   539篇
外国民族医学   7篇
外科学   1593篇
综合类   4613篇
现状与发展   2篇
预防医学   939篇
眼科学   806篇
药学   7804篇
  29篇
中国医学   3844篇
肿瘤学   606篇
  2024年   71篇
  2023年   249篇
  2022年   490篇
  2021年   753篇
  2020年   697篇
  2019年   599篇
  2018年   795篇
  2017年   868篇
  2016年   983篇
  2015年   886篇
  2014年   2009篇
  2013年   1853篇
  2012年   2079篇
  2011年   2163篇
  2010年   1617篇
  2009年   1337篇
  2008年   1220篇
  2007年   1281篇
  2006年   1166篇
  2005年   1019篇
  2004年   745篇
  2003年   657篇
  2002年   576篇
  2001年   470篇
  2000年   354篇
  1999年   305篇
  1998年   232篇
  1997年   196篇
  1996年   170篇
  1995年   149篇
  1994年   134篇
  1993年   96篇
  1992年   70篇
  1991年   97篇
  1990年   79篇
  1989年   53篇
  1988年   59篇
  1987年   42篇
  1986年   29篇
  1985年   59篇
  1984年   50篇
  1983年   36篇
  1982年   37篇
  1981年   32篇
  1980年   17篇
  1979年   27篇
  1978年   23篇
  1977年   17篇
  1976年   11篇
  1975年   13篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
A. Kamalam  A. S. Thambiah 《Mycoses》1982,25(9):512-516
Summary: Basidiobolomycosis following intramuscular injection in a 6 year old female child is reported. Regional lymph nodes in the inguinal areas on both sides conforms to such findings in our previous cases, denoting that this infection is systemic. Simple oral potassium iodide (KI) has cured the disease without a relapse during follow up of nearly 3 years.
Zusammenfassung: Bei einem 6jährigen Mädchen entwickelte sich im Anschluß an eine intramuskuläre Injektion eine Basidiobolomykose. Ähnlich wie bei anderen Fäillen lag eine Beteiligung der regionalen Lymphknoten in beiden Leisten vor, wodurch eine systemische Ausbreitung angezeigt wird. Behandlung mit Kaliumjodid oral führte zur vollständigen Heilung ohne Rückfall bei dreijähriger Nachbeobachtungszeit.  相似文献   
992.
Anti-tetanus toxoid F(ab′)2 fragments were purified using immune-affinity chromatography on tetanus toxoid-Sepharose. Fragments were labeled with125I. Labeled or non-labeled fragments were injected into the intrathecal space of rats. The labeled fragments were found in the spinal cord outside but not inside neurons.Tetanus toxin was injected into a muscle and 36 h later labeled fragments were injected intracisternally. After another 24 h the label was elevated in the spinal cord half segments giving neural supply to the injected muscle and in these half-segments the label was concentrated around some α-motoneurons.[125I]Tetanus toxin was injected into a muscle and at different times thereafter non-labeled fragments were injected intracisternally. The development of hindlimb rigidity but not the accumulation of [125I]tetanus toxin in α-motoneurons was prevented by early intracisternal injection of fragments. Injection of fragments after the appearance of hindlimb rigidity did not revert the rigidity but prevented the further development of symptoms.It is concluded that an action of tetanus toxin inside α-motoneurons is of no importance for the development of motor symptoms in clinical tetanus. The data suggest that in order to evoke spinal symptoms of toxicity tetanus toxin has to reach interneurons by transneuronal migration. In the very early stages of clinical tetanus the intrathecal injection of fragments may be useful.  相似文献   
993.
994.
A method is described which allows intracranial injection of drug solutions through glass micropipettes (tip diameter 15 micron) in the freely moving rat by use of air pressure. Compared with conventional injection methods through steel cannulae this method has the advantages of (1) minimal destruction of brain tissue, (2) precise injection of small volumes of solutions (1 nl to several microliters), (3) simultaneous recording of local EEG activity, and (4) usage of multipipette assemblies.  相似文献   
995.
Cholecystokinin (CCK) peptides and receptors have been shown to be present in the brain as well as in gastrointestinal organs. While functions for peripheral CCK are well recognized, those for central CCK peptides are only now being investigated. We have shown previously that CCK-octapeptide (CCK-OP) is a very potent and specific suppressor of feeding when administered in the cerebral ventricles of sheep. In the present study the objective was to determine the relative potency of several CCK analogues in inhibiting feeding when administered as 75 min continuous injections into the lateral cerebral ventricles of 2-hr fasted sheep. In comparing feeding response during CCK-OP injections to that during caerulein injections, it was found that feed intakes were similar only at an equal molar dose (0.638 pmole/min); whereas three times as much CCK-33 (1.91 pmoles/min) as CCK-OP (0.638 pmoles/min) was required to produce similar feed intakes. Both caerulein (0.638 pmoles/min) and CCK-33 (1.91 pmoles/min) caused significant decreases in feeding compared to control (sCSF). Desulfated CCK-OP had no effect on feeding at a dose (0.638 pmoles/min) that causes 80–100% decreases in feeding when the C-7 tyrosine is sulfated. Feed intake was significantly less with 2.55 pmoles/min CCK-OP than with an equal dose of desulfated CCK-OP. These results concur with those of previous studies on specific CCK receptors in the pancreas and in the brain, and therefore support the concept of specific CCK receptors in brain having a role in satiety.  相似文献   
996.
A comparison of the effects of extracellular and intracellular thirst stimuli on plasma levels of angiotensin II was made in rats. The administration of polyethylene glycol and isoproterenol elicited a strong drinking response and resulted in a significant increase in plasma angiotensin II. There was a significant correlation between the volume of water intake and plasma angiotensin II levels following the injection of polyethylene glycol but not following isoproterenol. Drinking was also elicited by the administration of hypertonic saline but there was no increase in plasma angiotensin II. The results suggest that endogenously released angiotensin II contributes to extracellular thirst but not to intracellular thirst.  相似文献   
997.
The dopamine agonist, 2-(N,N-dipropyl)amino-5,6-dihydroxytetralin, was injected at 78 different locations within and around the striatum of the guinea-pig. Injection sites were selected at anterior 10.0, 8.0 and 6.0mm to the inter-aural line, ±2.5, ±3.5 and ±4.5 mm lateral from the midline and 1–10 mm below guide cannulae placed to penetrate 0.75 mm into the cerebral cortex. All animals were observed for the development of biting behaviour and hyperactivity. Four important distinctions could be made between the loci of tetralin action to induce biting and hyperactivity. The most striking distinction was the development of marked hyperactivity in the absence of any consistent biting at the most lateral placements (±4.5 mm) in the entire rostral-caudal plane. Secondly, within the lateral regions the dorsal locations were the more sensitive (in contrast to the more marked development of biting in the ventro-medial caudate) and, thirdly, even in those medial planes where the ventral locations sustained the most consistent biting, induction of hyperactivity was most marked from the more dorsal locations which failed to sustain a consistent biting. Fourthly, the most rostrally located injections, even at the medial sites, produced marked hyperactivity but only modest biting responses. Finally, it should be noted that both hyperaetivity and biting could be induced from extrastriatal sites, although the delayed onset may reflect the need for diffusion. This data would indicate a differential distribution of striatal sites capable of mediating biting and hyperactivity. Specific, but differential, blockade of these responses by the neuroleptic agents fluphenazine and tiapride (atropine, methysergide, dl-propranolol and piperoxan were ineffective) may indicate that dopamine mechanisms at the two sites may have differing characteristics.  相似文献   
998.
A 41-year-old woman presented with a history of a solitary pustular erythematous lesion occurring at the site of a Mantoux test performed 10 months previously. The histopathology examination revealed a suppurative and foreign body giant cell reaction to numerous keratin flakes. Culture of the tissue was negative for both aerobic and anaerobic organisms including mycobacteria. We postulate that the reaction in our patient may have been secondary to the implantation of epidermal keratin or the entrapment of hair into the dermis during the intradermal injection of tuberculin purified protein derivative.  相似文献   
999.
Plasma cell cheilitis is an idiopathic, benign, inflammatory condition characterized by a dense band-like infiltrate of plasma cells in the oral mucosa. In addition to the lips, the disease can affect the penis, vulva, buccal mucosa, palate, gingiva, tongue, epiglottis, and larynx. Some authors have shown the effectiveness of topical or intralesional corticosteroids; however, there have been many reports describing poor therapeutic responses to topical steroids. We describe three patients with plasma cell cheilitis whose clinical condition responded rapidly to the intralesional injection of corticosteroids.  相似文献   
1000.
OBJECTIVES: To determine the effects of 'coasting' on the outcome of controlled ovarian hyperstimulation (COH) and intracytoplasmic sperm injection-embryo transfer (ICSI-ET). DESIGN: Retrospective study. SETTING: IVF Centre, Ozel Ege Tup Bebek Merkezi, Izmir, Turkey. SAMPLE: Twenty-six coasted and 52 non-coasted COH and ICSI-ET patients were enrolled in this retrospective study. METHODS: Coasted patients were enrolled consecutively during the study period, and two non-coasted controls were selected from our database for each coasted patient. Coasting was decided when serum oestradiol level was > or = 4000 pg/mL. Groups were compared using chi2 and Mann-Whitney U-tests for statistical analysis. MAIN OUTCOME MEASURES: Number of oocytes collected, metaphase II (MII) oocytes and cleaving embryos, the fertilisation rate and clinical pregnancy rate were the main outcome measures. RESULTS: Number of oocytes collected, number of MII oocytes, number of cleaving embryos, fertilisation rate and clinical pregnancy rate for the coasted and non-coasted groups were 15.5 +/- 5.2 and 14.0 +/- 7.1, 9.7 +/- 4.8 and 9.3 +/- 3.9, 6.8 +/- 3.9 and 5.8 +/- 3.1, 0.85 +/- 0.18 and 0.78 +/- 0.18, 13/26 and 24/52, respectively; these differences were not statistically significant. None of the patients in the coasted group were hospitalised for signs or findings of severe ovarian hyperstimulation syndrome. CONCLUSIONS: Coasting does not adversely affect the number and the function of mature oocytes and the clinical pregnancy rate.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号