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991.
Ken Takumi Norio Iijima Kinuyo Iwata Shimpei Higo Hitoshi Ozawa 《The journal of physiological sciences : JPS》2012,62(6):453-460
Kisspeptins, encoded by Kiss1 gene, play pivotal roles in the regulation of reproduction. Recently, several studies reported a sex difference in Kiss1 expression in the arcuate nucleus (ARC) during the neonatal period. In this study, we investigated the effect of gonadal steroid manipulation on the sex difference in Kiss1 expression in ARC of rats. At neonatal and prepubertal stages, females had a greater number of Kiss1 neurons than the males. Gonadectomy at those stages resulted in significant increases in the Kiss1 neuron number and the sex differences disappeared. We also confirmed the expression of estrogen receptor ?? in kisspeptin neurons in neonates. Altogether, our results indicate that ARC Kiss1 expression is negatively regulated by gonadal steroids from early postnatal stages, and that the sex difference in ARC Kiss1 expression is attributed to the difference in circulating gonadal steroid levels. We also found that neonatal estrogenization inhibits Kiss1 expression and impairs negative feedback system. 相似文献
992.
Swine hemagglutinating encephalomyelitis virus (HEV) has been shown to have a capability to gain access to the cell bodies of sensory neurons after peripheral inoculation, resulting in ganglionic infection. It is not clearly understood how this virus is replicated within and released from the sensory neurons, and it remains to know how satellite cells response to the HEV invasion. By ultrastructurally examining HEV-infected rat dorsal root ganglia, we found that HEV in the cell bodies of infected neurons budded from endoplasmic reticulum-Golgi intermediate compartments, and were assembled either individually within small vesicles or in groups within large vesicles. The progeny virions were released from the sensory neurons mainly by smooth-surfaced vesicle-mediated secretory pathway, which occurred predominantly at the perikaryal projections and infoldings of sensory neurons. Released HEV particles were subsequently taken up by the adjacent satellite cells. Almost all virus particles in the cytoplasm of satellite cells were contained in groups within vesicles and lysosome-like structures, suggesting that these glial cells may restrict the local diffusion of HEV. These observations give some insights into the pathogenesis of coronavirus infection and are thought to help understand the interactions between sensory neurons and their satellite cells. 相似文献
993.
Plain abdominal radiography is a very basic examination and plays an important role in primary care. The objectives of this study were to clarify colon distributions on plain abdominal radiographs. Forty-three healthy volunteers underwent gastric fluoroscopy, and 2 hours later, plain abdominal radiography in the supine position. A region of interest (ROI) was defined uniformly on each X-ray image to divide the image into 600 zones. The area corresponding to the large bowel within the ROI was divided into 4 segments (ascending colon, transverse colon, descending colon, and sigmoid colon + rectum). The percentage of barium in each segment relative to the total volume of barium used was calculated to evaluate the percent ROI occupancy. The large bowel covered 76.7% of the entire ROI, with the percent duplication being 55%. The duplicated area corresponded to the transverse colon region. When the method proposed by Arhan et al. was used, the percentage of the colon actually present in each segment relative to that determined theoretically was 99.6% for the right colon segment, 92.2& for the left colon segment, and 92.2% for the sigmoid/rectal segment. However, in cases in which the transverse colon descended partially from the fifth lumbar vertebra, the percentage occupied by the sigmoid colon + rectum decreased to 57.2%. We applied a new large bowel segmentation method especially for patients with ptosis, by devising a line joining the lateral side of the right lesser pelvis and the lower ends of both sacroiliac joints. 相似文献
994.
Toshiki Katsura Norio Miura Akiko Hoshino Kanae Usui Yasuro Takahashi Seiichi Hisamoto 《Journal of Rural Medicine》2011,6(2):71-80
Objective: The objective of this study was to verify the recognition of
dangers and obstacles within a house in the elderly when walking based on analyses of gaze
point fixation.Materials and Methods: The rate of recognizing indoor dangers was compared
among 30 elderly, 14 middle-aged and 11 young individuals using the Eye Mark Recorder.Results: 1) All of the elderly, middle-aged and young individuals showed a
high recognition rate of 100% or near 100% when ascending outdoor steps but a low rate of
recognizing obstacles placed on the steps. They showed a recognition rate of about 60%
when descending steps from residential premises to the street. The rate of recognizing
middle steps in the elderly was significantly lower than that in younger and middle-aged
individuals. Regarding recognition indoors, when ascending stairs, all of the elderly,
middle-aged and young individuals showed a high recognition rate of nearly 100%. When
descending stairs, they showed a recognition rate of 70-90%. However, although the
recognition rate in the elderly was lower than in younger and middle-aged individuals, no
significant difference was observed. 2) When moving indoors, all of the elderly,
middle-aged and young individuals showed a recognition rate of 70%-80%. The recognition
rate was high regarding obstacles such as floors, televisions and chests of drawers but
low for obstacles in the bathroom and steps on the path. The rate of recognizing steps of
doorsills forming the division between a Japanese-style room and corridor as well as
obstacles in a Japanese-style room was low, and the rate in the elderly was low, being 40%
or less.Conclusion: The rate of recognizing steps of doorsills as well as obstacles
in a Japanese-style room was lower in the elderly in comparison with middle-aged or young
individuals. 相似文献
995.
Tanahashi N Nakagawara J Okada Y Minematsu K;Challenge-Stroke Study Group 《Expert review of cardiovascular therapy》2011,9(9):1115-1126
The Challenge-Stroke study was conducted in Japanese patients initiated on candesartan cilexetil therapy within 3 months of suffering a stroke to investigate the clinical use of candesartan and its efficacy/safety in this therapeutic setting. A total of 869 patients formed the safety analysis set. In total, 79.6% of patients with brain hemorrhage (BH) and 60.2% with brain infarction (BI) began candesartan before post-stroke day 3 and 7, respectively. Baseline average blood pressure (BP) was 152.0/83.2 mmHg in the BH group and 165.2/89.8 mmHg in the BI group; this was reduced to 125.8/75.4 mmHg and 136.3/78.1 mmHg, respectively, at 1 year. The incidence of adverse drug reactions was 6.7 and 8.0%, respectively. There were 12 recurrent strokes in the BH group and 11 in the BI group after 1 year. The risk of recurrent stroke was significantly higher for BH patients with a final systolic BP ≥150 mmHg than for those with a final systolic BP <130 mmHg (hazard ratio: 6.807; p = 0.004). Aggressive antihypertensive therapy is currently employed in Japanese patients with acute stroke. Candesartan was safe and effective for BP control in acute stroke patients. Strict BP management may be useful for secondary prevention of stroke after BH. 相似文献
996.
Ridruechai C Sakurada S Yanai H Yamada N Kantipong P Piyaworawong S Dhepakson P Khusmith S Keicho N 《The Southeast Asian journal of tropical medicine and public health》2011,42(4):876-889
The T helper type 1 (Th1) immune response plays an important role in protective immunity, pathophysiology and development of tuberculosis (TB). To investigate whether osteopontin (OPN) and other Th1 response-related molecules are associated withTB disease status, including co-infection with HIV, and response to anti-TB treatment, circulating levels of full-length OPN (F-OPN), thrombin-cleaved N-terminal fragment of OPN (N-half OPN), IFN-gamma, IP-10, IL-18, IL-12/ IL-23 (p40), IL-10, IL-15 and C-reactive protein (CRP) were measured before and after anti-TB treatment. Patients with newly active pulmonary TB had significantly higher plasma levels of F-OPN, IFN-gamma and CRP than healthy controls (HC). F-OPN, N-half OPN, IFN-gamma, IP-10, IL-18 and IL-10 levels were higher in patients with extensive TB/HIV co-infection than in patients with a single disease of TB or HIV. Plasma levels of F-OPN correlated well with those of IP-10, IL-18 and N-half OPN among patients with active TB. The F-OPN, IFN-gamma, IP-10 and CRP levels decreased significantly after effective anti-TB treatment. These data suggest that circulating OPN and Th1 response-related molecules, including IFN-gamma, may be regulated in response to expansion of active TB and could serve as markers of disease activity before and during treatment. 相似文献
997.
Objective
There were many cases of pandemic influenza A (H1N1) 2009 (H1N1/09) in Japan during the 2009–2010 epidemic. They accounted for 16% of the total population (20.7 million/128 million), and 59% of the patients were children 15 years of age and under (12.2 million/20.7million). However, there were only 38 paediatric deaths. We analyzed the clinical manifestations and treatment of children hospitalized because of H1N1/09 infection in order to clarify the association between treatment with neuraminidase inhibitors and the low mortality rate.Methods
A retrospective chart review was performed on a total of 1000 paediatric inpatients.Results
The causes of the hospitalizations were respiratory complications in 651 cases (65.1%), neurological complications in 255 cases (25.5%) and other complications in 94 cases. Neuraminidase inhibitors, primarily oseltamivir, had been used to treat 984 (98.4%) of the 1000 patients, and in 88.9% of the patients, treatment with neuraminidase inhibitors was initiated within 48 h after the onset of illness. Only 12 (1.2%) of the 1000 patients underwent mechanical ventilation, and one patient died of H1N1/09 infection.Conclusions
Although a high proportion of the patients in this study had severe respiratory complications, the case fatality rate was only 0.1%. The low mortality rate of children due to the H1N1/09 epidemic in Japan was probably attributable to the universal implementation of early treatment with neuraminidase inhibitors. 相似文献998.
999.
1000.