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91.
Objectives. To describe nurse migration patterns in the Philippines and their benefits and costs.
Principal Findings. The Philippines is a job-scarce environment and, even for those with jobs in the health care sector, poor working conditions often motivate nurses to seek employment overseas. The country has also become dependent on labor migration to ease the tight domestic labor market. National opinion has generally focused on the improved quality of life for individual migrants and their families, and on the benefits of remittances to the nation. However, a shortage of highly skilled nurses and the massive retraining of physicians to become nurses elsewhere has created severe problems for the Filipino health system, including the closure of many hospitals. As a result, policy makers are debating the need for new policies to manage migration such that benefits are also returned to the educational institutions and hospitals that are producing the emigrant nurses.
Conclusions and Recommendations. There is new interest in the Philippines in identifying ways to mitigate the costs to the health system of nurse emigration. Many of the policy options being debated involve collaboration with those countries recruiting Filipino nurses. Bilateral agreements are essential for managing migration in such a way that both sending and receiving countries derive benefit from the exchange.  相似文献   
92.
Modifying potentials of various chemicals on tumor development were investigated in a wide-spectrum organ carcinogenesis model using male F344/DuCrj rats. The animals were treated with N-nitroso-diethylamine (100 mg/kg body weight, ip, single injection at the commencement of the study), N-methyl-N-nitrosourea (20 mg/kg body weight, ip, 4 times during weeks 1 and 2) and N-bis(2-hydroxypropyl)nitrosamine (0.1% in drinking water, during weeks 3 and 4) for multi-organ initiation and then were given one of 14 test chemicals including 6 hepatocarcinogens, 7 non-hepatocarcinogens and 1 non-carcinogen, or basal diet for 16 weeks. All rats were killed at the end of week 20, and the major organs were carefully examined for preneoplastic and neoplastic lesions. Immunohistochemical demonstration of glutathione S -transferase-positivc foci was also used for quantitative assessment of liver preneoplastic lesion development. Modifying effects were shown for 11 out of 14 test agents in the liver, forestomach, glandular stomach, lung, urinary bladder or thyroid, 7 of them targeting more than two organs. This was the first demonstration to our knowledge that cloflbrate possesses enhancing potential for urinary bladder carcinogenesis and an inhibiting effect on thyroid carcinogenesis. Caprolactam showed no effect in any organ, in agreement with its established inactivity. The results indicated that the system could be reliably applied as a medium-term multiple organ bioassay for assessment of the modification potential of test agents in unknown target sites.  相似文献   
93.
Pigs of different ages were studied to assess the effect of age on the development of the testes after intra-abdominal transection of the testicular artery and vein. Transection of the testicular artery and vein at different stages of sexual development had a variable effect on the growth and differentiation of the testes. Transection performed at a young age (2 months) had no effect on the development of the testes (previous study). The animals used in this study were between 3 and 12 months (adult) at the time of surgical intervention. Their testes appeared to be more sensitive to disturbance of the main blood supply. The alternative vascular pedicle (vasal artery) was unable to adapt sufficiently to the increased physiological requirements of the testis during development in more than 50% of the animals. The results obtained from adult males indicate that intra-abdominal transection of the testicular vessels invariably has a deleterious effect on the testis.  相似文献   
94.
95.
目的通过观察胚龄12、14、16天胎鼠和生后1天的仔鼠的后肾组织体外培养的存活发育情况,与同期在体比较,建立能模拟体内生存环境稳定的肾组织培养模型。方法采用体外培养倒置显微镜观察,光镜连续切片技术结合体视学定量分析方法,观察、检测培养后肾组织的存活情况以及培养前后肾脏皮质的发育状况。结果对同一胚(日)龄小鼠后肾组织随培养时间逐渐发育,直至成熟;且随胚(日)龄的增加,肾组织块存活比率逐渐下降,肾脏皮质的发育呈下降趋势。结论小鼠后肾组织体外培养胚(日)龄越小其存活发育情况越好,E12天取材培养的肾组织与在体发育一致,利用微孔膜肾组织培养是一种简便有效的神经组织体外培养方法。  相似文献   
96.
Summary Ultrastructural features of juvenile cestodes (metacestodes) can provide useful characters for phylogenetic and evolutionary analyses. Until now, however, they have been relatively little utilised (Beveridge 2001, Chervy 2002). The postembryonic development and structure of fully formed metacestodes were examined in two cyclophyllideans: Taenia parva Baer, 1926 (Taeniidae); and Sobolevitaenia verulamii (Mettrick, 1958) Korniushin, 1972 (Dilepididae). In T. parva, three developmental stages were recognized: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing metacestode strobila and an obvious decrease in the size of the central vesicle; (3) a fully formed metacestode of the strobilocercus type with 14–24 invaginated scoleces. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity to the same structures in adults at both LM and TEM levels. The morphogenesis of the metacestode of T. parva is compared with that of polycephalic metacestodes of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually multiplying metacestodes (Mesocestoides vogae, hymenolepidids and dilepidids). In S. verulamii, the body of the cysticercoid with invaginated scolex armed with a double crown of rostellar hooks was completely surrounded by the cercomer, which appears to be separated from the cyst and scolex. The surface of the suckers is covered with a thick layer of glycocalyx. Five cell types were distinguished in the sections: (1) perikarya of metacestode tegument; (2) glycolgen-storing parenchymal cells; (3) glandular-type cells with large, electron-dense secretory-like granules; (4) flame cells; and (5) calcareous corpuscle-forming cells. The surface of the cercomer is covered by elongated microvilli, which evidently differ from characteristic microtriches covering all other parts of the metacestode surface. The ultrastructure of S. verulamii evidently differs from that of the other dilepidid cestode examined to date, Lateriporus geographicus, the cyst wall of which more resembles cysticercoids of Hymenolepididae than those of Dilepididae. Concluding remarks: Ultrastructural studies on metacestodes have considerable promise for providing important new characters for phylogenetic analysis. New TEM data on a great variety of cestode species are urgently needed. Until now, this field has not been exploited in a systematic fashion. Until more comprehensive studies become available, the current data are not yet amenable to analysis.  相似文献   
97.
目的 探讨血清瘦素在男生青春期发育中的作用。方法 健康男生170名,调查首次遗精时间,测定血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平,采用多元Logistic回归模型分析男生青春期发育的影响因素;同时,连续两年观察,分析血清瘦素在青春期的动态变化。结果 末次研究已遗精组血清瘦素、睾酮、促卵泡成熟激素、黄体生成激素水平均明显高于未遗精组。多因素分析显示血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素。初次资料分析,遗精前组血清瘦素、睾酮明显高于未遗精组。结论 血清瘦素、睾酮、促卵泡成熟激素、体重为男生青春期发育的独立影响因素,男生遗精前期血清瘦素、睾酮已有明显改变。  相似文献   
98.
Background In the last few years, experimental data have been reported on differences in implicit memory processes of genetically distinct groups of individuals with Intellectual Disability (ID). These evidences are relevant for the more general debate on supposed asynchrony of cognitive maturation in children with abnormal brain development. This study, comparing implicit memory processes in individuals with Williams syndrome (WS) and Down syndrome (DS), was planned to verify the ‘etiological specificity’ hypotheses pertaining to the skill learning abilities of individuals with ID. Method A modified version of Nissen and Bullemer's (1987) Serial Reaction Time (SRT) task was used. The performances of three group were evaluated. The first group consisted of thirty‐two people with WS (18 males and 14 females). The second group was comprised of twenty‐six individuals with DS (14 males and 12 females). The two groups of individuals with ID were selected so that the groups were comparable as for mental age and chronological age. The third group consisted of forty‐nine typically developed children with a mental age similar to that of the groups with WS and DS. Results The two groups of individuals with ID demonstrated different patterns of procedural learning. WS individuals revealed poor implicit learning of the temporal sequence of events characterizing the ordered blocks in the SRT task. Indeed, differently from normal controls, WS participants showed no reaction time (RT) speeding through ordered blocks. Most importantly, the rebound effect, which so dramatically affected normal children's RTs passing from the last ordered to the last block, had only a marginal influence on WS children's RTs. Differently from the WS group, the rate of procedural learning of the participants with DS was comparable to that of their controls. Indeed, DS and typically developed individuals showed parallel RT variations in the series of ordered blocks and, more importantly, passing from the last ordered to the last block. Therefore, a substantial preservation of skill learning abilities in this genetic syndrome is confirmed. Conclusions The results of the present study document that procedural learning in individuals with ID depends on the aetiology of the syndrome, thus supporting the etiological specificity account of their cognitive development. These results are relevant for our knowledge about the qualitative aspects and the underlying neurobiological substrate of the anomalous cognitive development in mentally retarded people.  相似文献   
99.
Ibotenate, a glutamatergic agonist, was used to study the spectrum of excitoxic disturbances at different ages of cerebral development. Cultures of whole mouse embryo were submitted to ibotenate at E8 for 20 h: during the phase of early premigratory differentiation; ibotenate did not induce any detectable histological lesion. During migration of supragranular neurons, newborn hamsters intracerebrally injected at P0 with ibotenate display neuronal migration disorders graded from nodular heterotopias to extensive laminar heterotopias mimicking some aspects of lissencephalic and double-cortex syndromes. After completion of neuronal layer V, P0 mice injected with ibotenate exhibit laminar neuronal depopulation of layer V-VIa mimicking human micro-gyria. At P5 in mouse, after completion of neuronal migration of the cortical plate, ibotenate induces neuronal loss in all cortical layers and the formation of porencephalic cysts. This study emphasizes the dramatic role played by glutamate in brain development, in the occurrence of neuronal migration disorders in the cortex. and in grey and white matter damage.  相似文献   
100.
对89名单纯性肥胖儿童做了手腕部骨龄发育的病例对照研究。结果表明:(1)肥胖儿童骨龄提前(平均男孩提前1.02岁,女孩提前0.74岁,P<0.001)。(2)肥胖儿童骨骼发育速度比正常儿童快(平均男孩快0.117y/a,女孩快0.09y/a,P<0.001)。(3)男孩肥胖度与骨龄增值之间以及骨龄与身高之间均存在有同向变化关系。  相似文献   
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