全文获取类型
收费全文 | 11962篇 |
免费 | 615篇 |
国内免费 | 54篇 |
专业分类
耳鼻咽喉 | 173篇 |
儿科学 | 272篇 |
妇产科学 | 135篇 |
基础医学 | 1467篇 |
口腔科学 | 296篇 |
临床医学 | 801篇 |
内科学 | 3097篇 |
皮肤病学 | 272篇 |
神经病学 | 1071篇 |
特种医学 | 269篇 |
外科学 | 1966篇 |
综合类 | 66篇 |
预防医学 | 480篇 |
眼科学 | 181篇 |
药学 | 796篇 |
中国医学 | 32篇 |
肿瘤学 | 1257篇 |
出版年
2023年 | 71篇 |
2022年 | 136篇 |
2021年 | 245篇 |
2020年 | 140篇 |
2019年 | 194篇 |
2018年 | 261篇 |
2017年 | 201篇 |
2016年 | 215篇 |
2015年 | 228篇 |
2014年 | 339篇 |
2013年 | 358篇 |
2012年 | 616篇 |
2011年 | 640篇 |
2010年 | 403篇 |
2009年 | 305篇 |
2008年 | 536篇 |
2007年 | 630篇 |
2006年 | 614篇 |
2005年 | 604篇 |
2004年 | 541篇 |
2003年 | 527篇 |
2002年 | 554篇 |
2001年 | 391篇 |
2000年 | 437篇 |
1999年 | 333篇 |
1998年 | 121篇 |
1997年 | 109篇 |
1996年 | 104篇 |
1995年 | 79篇 |
1994年 | 73篇 |
1993年 | 65篇 |
1992年 | 232篇 |
1991年 | 213篇 |
1990年 | 188篇 |
1989年 | 234篇 |
1988年 | 169篇 |
1987年 | 177篇 |
1986年 | 155篇 |
1985年 | 139篇 |
1984年 | 93篇 |
1983年 | 87篇 |
1979年 | 91篇 |
1978年 | 59篇 |
1977年 | 49篇 |
1974年 | 50篇 |
1973年 | 51篇 |
1972年 | 63篇 |
1970年 | 47篇 |
1969年 | 54篇 |
1968年 | 55篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
METHODS: We measured the dimensions of the intercondylar notch of the femur in 32 patients with primary severe osteoarthrosis (OA) of the knee and 54 embalmed cadaveric knees. RESULTS: There were 56 knees with morphologically normal anterior cruciate ligament (ACL), 11 knees with lax or partially ruptured ACL and 19 knees with missing ACL. The average width of the intercondylar notch in knees with lax and missing ACL was significantly narrower than that of knees with normal ACL. In addition, knees with missing ACL had a significantly smaller notch depth than knees with normal ACL. In medial compartment OA (56 knees), the notch width and depth in knees with severe OA (37 knees) were significantly smaller than those in normal (19 knees) and mild to moderate OA groups (19 knees). CONCLUSION: Our results indicate that osteophyte growth in the femoral intercondylar notch seems to correlate with the progression of medial compartment OA of the knee. 相似文献
992.
Fifteen patients with nonparasitic hepatic cysts underwent surgery to relieve abdominal complaints, at the First Surgical Department, Tokyo University Hospital between 1966 and 1989. Total removal of the cyst was carried out in 14 of the patients, while puncture and aspiration only were performed in the other patient in whom a cyst had ruptured spontaneously, after which hemoperitoneum was observed at emergency laparotomy. The size of the cysts varied from 7-19 cm with a mean of 12.4 cm. Histological study revealed a congenital cyst in 14 patients and a cystadenoma in one. The epithelium lining of the internal surface of the congenital cysts was highly atrophic and desolated and often disappeared. Examination of the cyst fluid revealed the same concentration of electrolytes as in the serum. Hepatic enzyme levels were usually lower than in the serum, but lactic dehydrogenase and aminotransferase levels were elevated in a few cases. Tumor marker levels of the cyst fluid were higher than those in the serum in four of five patients examined. 相似文献
993.
The retrograde transneuronal viral cell body labeling method was used to study the CNS nuclei that innervate the parasympathetic preganglionic neurons which project to the pterygopalatine ganglion. Small injections of a suspension of pseudorabies virus (PRV) were made in the pterygopalatine ganglion of rats and after 4 days their brains wer e processed for immunohistochemical detection of PRV. Some of the tissues were stained with a dual immunofluoresence method that permitted the visualization of PRV and neurotransmitter enzyme or serotonin immunoreactivity in the same cell. Retrograde cell body labeling was detected in the ipsilateral ventrolateral medulla oblongata in the region that has been termed the superior salivatory nucleus. This area was the same region that was retrogradely labeled after Fluoro-Gold dye injections in the pterygopalatine ganglion. Retrograde transneuronally infected cell bodies that provide putative afferent inputs to the pytergopalatine parasympathetic preganglionic neurons were mapped throughout the brain. In the medulla oblongata, transneuronally labeled neurons were seen in the nucleus tractus solitarii, dorsomedial part of the spinal trigeminal nucleus and gigantocellular reticular nucleus. In most experiments, some A1 catecholamine cells and serotonin neurons of the raphe magnus, raphe pallidus, raphe obscurus, and parapyramidal nuclei were labeled. In the pons, labeled cells were found in the parabrachial nucleus. A5 catecholamine cell group, and non-catecholamine part of the subcoeruleus region. In the midbrain, cell body labeling was located in the central gray matter and retrorubral field. In the diencephalon, labeling was found mainly in the hypothalamus. The areas included the lateral hypothalamic area, lateral preoptic area, dorsomedial and paraventricular hypothalamic nuclei, and ventral zona incerta. Contralateral second order cell body labeling was seen in the tuberomammillary nucleus of the hypothalamus. Some of these cells were histidine decarboxylase-immunoreactive. In the forebrain, the bed nucleus of the stria terminalis, substantia innominata, and an area of the cerebral cortex called the amygdalopiriform transition zone were labeled. 相似文献
994.
Intracellular localization of the Menkes and Wilson''s disease proteins and their role in intracellular copper transport 总被引:3,自引:0,他引:3
Copper is a heavy metal ion essential for the activity of a variety of enzymes in the body. In excess, copper is a very toxic ion and therefore efficient regulation of its metabolism is required. This is dramatically illustrated by the genetic disorders X-linked Menkes disease and autosomal recessive Wilson's disease. In 1993, both the Menkes and Wilson's genes were isolated and it was found that these genes encode homologous cation copper transporting P-type ATPase proteins. The Menkes protein (ATP7A) is expressed in most tissues, except liver. In contrast, the Wilson's protein (ATP7B) is abundantly expressed in liver. Intracellular localization of those proteins was investigated. Both ATP7A and ATP7B are localized in the trans-Golgi network and post-Golgi vesicular compartment (PGVC) in the cell. This intracellular localization was altered by the copper content present in the cell. This result may support the hypothesis that ATP7A and ATP7B are involved in cellular copper transport and those proteins could be suitable models for elucidating intracellular copper metabolism. 相似文献
995.
The expression and serum level of NCC-ST-439, a tumor marker, has been investigated in 20 primary and 28 recurrent breast cancer patients, and the positive rate was found to amount to 21.1% in primary cases and 42.9% in recurrent cases, respectively, thereby indicating a positive correlation between the expression of NCC-ST-439 and the progression of the diseases. The accordance rate between NCC-ST-439 and CEA was 64.6%; in contrast, the rate between NCC-ST-439 and CA 15-3 was 82.1%, suggesting a difference in specificity against tumor between NCC-ST-439 and CEA. The change in the serum level of NCC-ST-439 in recurrent cases clearly correlated with the effectiveness of the therapy. These findings suggest that measurement of the NCC-ST-439 level, especially in combination with the CEA level, may be useful for the early detection and the monitoring of relapses in breast cancer patients. 相似文献
996.
Preparation of recombinant protein A-lymphotoxin chimeric protein and its antitumor effects in mice 总被引:1,自引:0,他引:1
T Miki M Wada T Kasumimoto R Moriyama Y Iwasaki 《Japanese journal of cancer research》1991,82(2):227-232
We have investigated the in vivo function of a chimeric protein constructed by recombinant DNA techniques. The behavior and antitumor activity of a protein A-lymphotoxin chimera (ALT) was examined on a murine tumor in mice in comparison with amino-terminal 19 amino acid-deleted lymphotoxin (dLT). Seven-week-old male BALB/c mice were implanted intradermally with Meth-A fibrosarcoma on day 0. ALT and dLT caused tumor regression, hemorrhagic necrosis and complete regression in a dose-related way when each agent was given intratumorally 5 times (days 5-9). The ratio of the median effective doses for complete tumor regression was 1.6 between ALT and dLT on a molar basis. ALT caused tumor regression and body weight loss when given intravenously on the same schedule. Biodistribution studies with 125I-labeled ATL and dLT demonstrated that, after intratumoral administration, ALT was retained longer in the administered site and was cleared more slowly from the mouse body than dLT. These findings suggest that a protein A-lymphotoxin chimeric protein expresses both antitumor activity similar to that of lymphotoxin and characteristic in vivo behavior of the fused protein A portion. 相似文献
997.
J Falconer J A Wada W Martin D Li 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1990,17(1):35-39
During the investigation of intractable epilepsy, neuronal migration anomalies [NMA] were discovered in three patients. The first patient had abnormally positioned gray matter within the walls of both lateral ventricles. The second patient had a post operative cystic area in the right parietal-occipital lobes and an area of NMA within the right temporal lobe. The third patient had abnormally thickened gray matter in the right operculum. Long term CCTV-EEG monitoring of these three patients revealed ictal discharges originating from the area of abnormal gray matter in patients 2 and 3. PET scanning showed the areas of NMA in all three patients to have similar metabolic activity to normal gray matter. These cases illustrate the value of various imaging modalities and suggest some interesting physiology of a spectrum of neuronal migration anomalies. 相似文献
998.
Y Fujibayashi Y Yonekura Y Takemura K Wada K Matsumoto N Tamaki K Yamamoto J Konishi A Yokoyama 《Journal of nuclear medicine》1990,31(11):1818-1822
To clarify the relationship between the myocardial accumulation of 125I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) and intracellular adenosine-5'-triphosphate (ATP) content, the effect of 2,4-dinitrophenol (DNP, an electron transport uncoupler) on myocardial BMIPP accumulation was studied, in comparison with that of thallium-201-chloride (201Tl-Cl). In the mouse myocardium, DNP decreased the intracellular ATP and ADP levels, without affecting either acyl-CoA synthetase activity or the level of CoA-SH. Following treatment with DNP, decreases in myocardial BMIPP accumulation correlated well with those of ATP, while 201Tl-Cl showed slightly increased accumulation in the myocardium. Thus, in some diseases, BMIPP may be useful in evaluating myocardial ATP levels. 相似文献
999.
H Ikeda M Komatsu S Seino K Takahashi S Yasui M Mariko 《Kaku igaku. The Japanese journal of nuclear medicine》1990,27(7):719-724
123I-IMP is taken up by the pulmonary capillary endothelial cells during the first pass through the lung, and is slowly released from them. To look up the factors which influence on the prolonged 123I-IMP retention in the diseased lung, we examined the correlation between the 123I-IMP uptake during the first pass and the 123I-IMP retention. Patients with bronchial asthma had no abnormal finding in the chest X-ray photograph. However 123I-IMP release from their lungs was delayed. Some patients show a tendency that 123I-IMP uptake during the first pass was uneven, which suggested the change in amine uptake function of endothelial cells. However their correlation coefficients between the uptake during the first pass and the prolonged retention were very small. It was considered that the prolonged 123I-IMP retention in the diseased lung was not explained only by the change in uptake function of pulmonary capillary endothelial cell. 相似文献
1000.
T Mochizuki Y Kawaue I Imura S Wada T Tsuchiya 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1989,37(1):110-116
A report is presented on 9 cases of left ventricular rupture associated with acute myocardial infarction experienced at Tsuchiya Hospital from January 1983 to August 1987. These cases accounted for 2.6% of the 384 cases of acute myocardial infarction admitted during the same period. Cases of cardiac rupture were classified according to clinical symptoms and hemodynamic findings obtained into three types, blow out type, subacute type, and our newly added intermediate type. In the intermediate type, there is depression of blood pressure to the level of losing consciousness but improvement of blood pressure and consciousness through medical treatment and time is available to permit surgical treatment in comparison with the blow out type. The therapeutic results were studied by the types. Among the four cases of blow out type, closure of the ventricular rupture was made under the extracorporeal circulation in one case, release of tamponade only under thoracotomy in the CCU in one case, and medical treatment only in two case, but none of the cases survived. Surgical closure of the ventricular rupture was made in all the three cases of the subacute type and all the cases are surviving. Of the two cases of the intermediate type who underwent surgical closure of the ventricular rupture, only one case could be salvaged. In examining the risk factors of cardiac rupture, a high rate of cardiac rupture was observed in initial cases of myocardial infarction without a past history of angina attack and in cases of coronary occlusion without evidence of peripheral collateral flow by emergency coronary angiography. 相似文献