全文获取类型
收费全文 | 2513926篇 |
免费 | 221649篇 |
国内免费 | 6193篇 |
专业分类
耳鼻咽喉 | 38500篇 |
儿科学 | 77742篇 |
妇产科学 | 65235篇 |
基础医学 | 339484篇 |
口腔科学 | 69074篇 |
临床医学 | 239953篇 |
内科学 | 509893篇 |
皮肤病学 | 54898篇 |
神经病学 | 214225篇 |
特种医学 | 101569篇 |
外国民族医学 | 886篇 |
外科学 | 396406篇 |
综合类 | 56618篇 |
现状与发展 | 74篇 |
一般理论 | 997篇 |
预防医学 | 197550篇 |
眼科学 | 58577篇 |
药学 | 179414篇 |
4篇 | |
中国医学 | 4400篇 |
肿瘤学 | 136269篇 |
出版年
2018年 | 30825篇 |
2017年 | 25258篇 |
2016年 | 27808篇 |
2015年 | 30647篇 |
2014年 | 47075篇 |
2013年 | 64605篇 |
2012年 | 74382篇 |
2011年 | 78008篇 |
2010年 | 51805篇 |
2009年 | 53378篇 |
2008年 | 74481篇 |
2007年 | 77405篇 |
2006年 | 80331篇 |
2005年 | 75950篇 |
2004年 | 72643篇 |
2003年 | 69374篇 |
2002年 | 68645篇 |
2001年 | 115743篇 |
2000年 | 119155篇 |
1999年 | 101127篇 |
1998年 | 30980篇 |
1997年 | 28403篇 |
1996年 | 28146篇 |
1995年 | 27221篇 |
1994年 | 24791篇 |
1993年 | 22826篇 |
1992年 | 80522篇 |
1991年 | 77541篇 |
1990年 | 74466篇 |
1989年 | 71822篇 |
1988年 | 66711篇 |
1987年 | 65542篇 |
1986年 | 62088篇 |
1985年 | 59040篇 |
1984年 | 44708篇 |
1983年 | 38096篇 |
1982年 | 23307篇 |
1981年 | 20711篇 |
1980年 | 19386篇 |
1979年 | 41556篇 |
1978年 | 29275篇 |
1977年 | 24698篇 |
1976年 | 23039篇 |
1975年 | 24200篇 |
1974年 | 29829篇 |
1973年 | 28241篇 |
1972年 | 26487篇 |
1971年 | 24332篇 |
1970年 | 22948篇 |
1969年 | 21154篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Serum LH, FSH and testosterone were quantitated in 9 patients with pure motor stroke within 24-48 h of its reported onset. High circulating LH with normal or low testosterone was noted in 8 of them. In response to an intravenous bolus of GnRH, the LH responses were exaggerated in all, but the FSH responses in 7 of them were comparable to those in eugonadal age matched controls. The rise in testosterone following 2000U hCG daily for 3 consecutive days was insignificant in the patients group compared to the controls. The data suggest normally operative pituitary testicular feed-back but decreased Leydig cell response in pure motor stroke. 相似文献
992.
Kindling is a process in which episodic electrical stimulation permanently increases seizure susceptibility. One mechanism to account for a change in seizure susceptibility is some alteration in signal transduction, possibly at the level of second messenger systems. In this study, male Long-Evans rats were kindled in the amygdala, and Ca2+/calmodulin (Ca2+/CaM)-dependent protein phosphorylation was assessed at the site of the primary kindled focus using one- and two-dimensional gel electrophoresis. In vitro phosphorylation of membrane and cytosol fractions in the presence of absence of Ca2+/CaM did not differentiate kindled from nonkindled amygdaloid tissue. These results suggest that changes in Ca2+/CaM-dependent phosphorylation are not related to the mechanism(s) underlying the establishment of an amygdaloid kindled focus. 相似文献
993.
Zusammenfassung Die Osteotomie des Oberkiefers in der Le-Fort-I-Ebene, die heute routinemäßig in der Down-fracture-Technik durchgeführt wird, hat die chirurgische Behandlung skelettaler Dysgnathien grundlegend verändert. Sie ermöglicht eine dreidimensionale Korrektur des Oberkiefers und damit des gesamten Gesichtsschädels. Darüber hinaus kann der Oberkieferzahnbogen, zusätzlich zu einer Verlagerung des gesamten Oberkiefers, durch eine zusätzliche sagittale und transversale Osteotomie erweitert, verschmälert und verkürzt werden. Die Planung einer Oberkieferosteotomie erfolgt anhand des klinischen Bildes, der Kiefermodelle und des Fernröntgenbildes. Dabei muß der Unterkiefer frühzeitig mit in die Planung einbezogen werden, da er durch die Autorotation im Gelenk den Verlagerungen des Oberkiefers folgt. Erst durch eine gleichzeitige Osteotomie auch des Unterkiefers ergibt sich ein weites Indikationsspektrum für die Oberkieferosteotomie. Bei einer kombinierten Ober- und Unterkieferosteotomie ist praktisch jedes gewünschte Profil im unteren Gesichtsdrittel erzielbar.
Summary The osteotomy of the maxilla using the Le Fort I technique, today routinely performed in the down-fracture-technique, has changed surgical corrections of dentofacial deformities fundamentally. It offers a three-dimensional correction of the maxilla and also of the whole facial skull. Furthermore the upper dental arch can be expanded, intruded and shortened using a sagittal or transversal osteotomy in addition to a complete transposition of the maxilla. Planning of a maxillary osteotomy is performed under consideration of the clinical situation, the casts and the lateral cephalogram. The mandible must be considered at an early state of the preoperative planning, since the mandible will follow all transpositions of the maxilla by rotating with the TMJ. Only by performing a simultaneous osteotomy of the mandible, a broad spectrum of indications for maxillary osteotomy will result and practically every desired profile of the lower third of the face can be achieved using combined maxillary and mandibular osteotomies.相似文献
994.
995.
J Bliss-Holtz 《Scholarly inquiry for nursing practice》1991,5(2):113-23; discussion 125-6
A secondary analysis of data from 120 full-term infants was performed to determine whether temperature relationships between sites could be used to identify cold-stress prior to core temperature decrease. Axillary and rectal temperature readings were taken every 30 seconds with standardized mercury-in-glass thermometers, and the highest reading for axillary and rectal temperatures was used in data analysis. Three groups were identified when temperature site readings were compared: infants whose rectal temperature was higher than their axillary (group 1), infants who had equal axillary and rectal temperatures (group 2), and those whose axillary temperature was higher than the rectal reading (group 3). Further findings from data analysis suggested that infants whose rectal temperatures were within normal limits were either in a relatively neutral environmental state (group 1) or were maintaining their core temperatures through brown adipose tissue metabolism (group 3). 相似文献
996.
D Puluszézak A Bianchi J C Cazin M Cazin 《Methods and findings in experimental and clinical pharmacology》1991,13(6):419-425
A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug. 相似文献
997.
An area analysis is presented of deaths in Auckland that were ostensibly avoidable, by appropriate medical intervention and treatment. Mortality data from the National Health Statistics Centre for the period 1977-85 were used in the analysis. The definition of an avoidable death was based on the International Classification of Diseases (ICD) code using established criteria. Eight percent of deaths of people under 65 years of age met the criteria. The basic spatial entity for the analysis is the census area unit and maps of Auckland are presented to show the distribution of avoidable mortality. It is found that there are significant and consistent spatial variations. Three areas with avoidable mortality that is generally higher than elsewhere are apparent: in south Auckland; to the north-west of the central urban sector centered on Grey Lynn; and in the eastern parts of the central sector from Glenn Innes to Onehunga. 相似文献
998.
999.
D R Jordan R L Anderson J R Patrinely 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》1989,24(6):251-253
The authors describe a method for silicone intubation of a single patent canaliculus associated with a nasolacrimal duct obstruction. Although bicanalicular intubation is always preferable when possible, unicanalicular stenting is necessary when only one canaliculus is patent. A chief advantage of this technique is that the lacrimal stent is inaccessible to the child and thus cannot be accidentally pulled out. 相似文献
1000.
Keratography as a guide to selective suture removal for the reduction of astigmatism after penetrating keratoplasty 总被引:2,自引:0,他引:2
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty. 相似文献