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排序方式: 共有3381条查询结果,搜索用时 15 毫秒
61.
A Suzuki N Yasui H Hadeishi M Mizuno T Abumiya T Sampei S Nakajima 《Neurologia medico-chirurgica》1990,30(2):95-99
Numerous clinical classification systems have been developed for patients with ruptured intracranial aneurysms. However, most systems do not take age into account and are less reliable in elderly than in younger patients in terms of indications for early surgery and predicting the clinical outcome. The authors have studied this problem using our clinical classification system and, present here the results of 38 elderly patients (greater than or equal to 65 years of age) who underwent neck clipping and implementation of continuous ventricular drainage within 3 days of aneurysm rupture. The clinical outcome at 1 year after onset was considered "good" if the patient was able to function independently and "poor" if he or she was partially or fully dependent or had died. The preoperative level of consciousness was not significantly correlated with the outcome according to Spearman's nonparametric statistical analysis. Age, however, was a significant factor: the incidence of poor outcome was significantly higher in patients over age of 70 years than in those between 65 and 70 (p less than 0.05). Postoperative complications, which were previously found to be significantly related to the outcome in elderly patients, were significantly more common in patients who had a history of cardiac, pulmonary, hepatic, and/or renal disease than in those without such a history (p less than 0.005). The authors found that the prognostic accuracy of clinical classification systems, based on preoperative level of consciousness, is improved in geriatric cases if one point is added for patients over age of 70 years or those with a history of systemic diseases. Additional relevant factors included computed tomographic findings and pre-existing cerebral dysfunction. 相似文献
62.
Hiroyuki Yasui Kiyoshi Yamaoka Terumichi Nakagawa 《Journal of pharmacokinetics and pharmacodynamics》1995,23(2):183-203
A new hepatocellular diffusion model was developed to kinetically evaluate the hepatobiliary transport processes of drugs
in the perfusion system, based on the physiological structure of the liver. Since the equations describing the hepatocellular
diffusion phenomena were derived as image forms in the Laplace domain, the fast inverse Laplace transform (FILT) was adopted
to manipulate the image equations. Cefixime and cefpiramide were selected as model drugs. The concentrations in the perfusate
and the excreted amounts into the bile were simultaneously measured at appropriate intervals after the rapid administration
of each drug into the portal vein. The hepatocellular diffusion model was fitted to the biliary excretion profiles from rat
livers, by means of a nonlinear least squares program, MULTI(FILT). According to this model, the hepatobiliary transport process
of drug is kinetically separated into three steps, that is, the diffusion into and through the hepatocytes, the transfer from
the hepatocytes into the bile canaliculi, and the movement through the bile canaliculi to the outlet of bile duct. These steps
are characterized by the diffusion rate constant through hepatocytes (kdif), the permeability rate constant into the bile canaliculi (kbmc) and the transit time through the bile canaliculi to the outlet of bile duct (
), respectively. It was demonstrated that kdif of cefixime (0.023min1) was significantly smaller than that of cefpiramide (0.044 min1), while the differences in kbmc and
were not obvious between cefixime and cefpiramide. kbmc and
of both drugs were about 1.2 min1 and about 1.0 min, respectively. These parameters were correlated to the excretion ratio into the bile (Fbile) and the mean transit time from the sinusoid through the hepatocytes to the outlet of bile duct (
). 相似文献
63.
In order to elucidate the cause of body weight loss in the early stage of tumor progression, morphological changes of striated muscle were investigated in rabbits every 10 days after VX2 carcinoma implantation. The lean body mass started to decrease in the tumor-bearing rabbits 10 days after implantation, and body fat ratio showed a significant decrease from 30 days, different from the starved rabbits, whose lean body mass and body fat ratio started to decrease from 10 days. Morphological hallmarks of apoptosis in muscle cells were detected in tumor-bearing animals prior to the tumor growth but not in starved animals. These findings suggest that muscle cell apoptosis may be responsible for the body weight loss in the early tumor-bearing. 相似文献
64.
Geographical patterns of excess mortality in Spain explained by two indices of deprivation 总被引:2,自引:2,他引:0
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STUDY OBJECTIVE: To analyse the geographical patterns and the magnitude of the association between deprivation and mortality in Spain. To estimate the excess of mortality in more deprived areas of the country by region. DESIGN: Cross sectional ecological study using 1991 census variables and mortality data for 1987-1992. SETTING: 2220 small areas in Spain. MAIN RESULTS: A geographical gradient from north east to south west was shown by both mortality and deprivation levels in Spain. Two dimensions of deprivation (that is, Index 1 and Index 2) obtained by exploratory factor analysis using four census indicators were found to predict mortality: mortality over 65 years of age was more associated with Index 1, while mortality under 65 years of age was more associated with Index 2. Excess mortality in the most deprived areas accounted for about 35,000 deaths. CONCLUSIONS: Two indices of deprivation strongly predict mortality in two age groups. Excess number of deaths in the most deprived geographical areas account for 10% of total number of deaths annually. In Spain there is great potential for reducing mortality if the excess risk in more deprived areas fell to the level of the most affluent areas. 相似文献
65.
Suzuki T Ogata A Tashiro K Nagashima K Tamura M Yasui K Nishihira J 《Brain research. Brain research protocols》1999,4(3):271-279
We report here an effective and concise method to determine the localization of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, and its mRNA in the central nervous system of pre- and postnatal rats. This method allows for double staining to demonstrate localization of different molecules on the same tissue specimen at the levels of mRNA and proteins by in situ hybridization and immunohistochemistry, respectively. Additionally, the present method gives results more quickly than the conventional isotopic techniques. By use of this method, we carried out immunohistochemistry with an anti-rat MIF polyclonal antibody and demonstrated positive staining using the avidin-biotin complex method (ABC method). To detect its mRNA, we performed nonradioactive in situ hybridization using a digoxigenin (DIG)-labeled RNA probe prepared from a full length fragment of rat MIF cDNA. MIF was strongly expressed in the telencephalon on embryonic day 16. Non-radioactive in situ hybridization with a DIG-labeled RNA probe as well as the immunohistochemistry described here could be applicable to characterize localization of mRNA and proteins of different molecules on the same tissue specimen. 相似文献
66.
Rhabdomyosarcoma of the bladder in an adult 总被引:2,自引:0,他引:2
We report a case of rhabdomyosarcoma of the bladder in an adult. A 73-year-old male was referred to our hospital due to macrohematuria. Ultrasonography, CT and MRI revealed a bladder tumor, and cystoscopic biopsy of the tumor pathologically revealed rhabdomyosarcoma. Total cystectomy with ileal conduit urinary diversion was performed. Copyright Copyright 1999 S. Karger AG, Basel 相似文献
67.
Uchida T Tomita Y Anzai K Zhang QW Yoshikawa M Kishihara K Nomoto K Yasui H 《Transplantation》1999,68(11):1721-1727
An essential role of murine CD4+ T cells in immune reactivity and skin graft rejection in discordant xenogeneic combinations have been reported. Our study was conducted to further clarify the roles of CD4+ and CD8+ T cells in discordant skin xenograft rejection, by using CD4 and CD8 knockout [C57BL/6 Cr Slc (B6; H-2b) background] mice. When human skins were grafted on CD8 knockout mice or B6 mice, both hosts rejected human skin grafts within 12 days after grafting. By contrast, survival of human skin grafts was significantly prolonged in CD4 knockout mice (mean survival times=19.3+/-(SD) 1.6 days; median 19 days). Fully allogeneic C3H/He Slc (H-2k) skin grafts were rejected within 14 days in CD4 knockout mice, suggesting that non-CD4+ T cells in CD4 knockout mice were immunocompetent for allograft rejection. In spleens of these recipient mice, CD8+ T cells seemed to be activated 10 days after human skin grafting. Immunohistological analysis revealed the infiltration of CD8+ T cells at the site of transplanted human skin on CD4 knockout mice. To further examine the role of CD8+ T cells in CD4 knockout mice, human skin grafting was performed on day 0 followed by administration of anti-CD8 monoclonal antibody on days 0, 5, and 14. The administration of anti-CD8 monoclonal antibodies caused the significant prolongation of human skin graft survival. These results indicate the following two conclusions: (1) CD4+ T cells have an essential role in rejecting discordant human skin xenografts rapidly and (2) however, CD8+ T cells also are capable of rejecting discordant human skin xenografts. 相似文献
68.
Clinical study of growing up aneurysms: report of 25 cases 总被引:1,自引:0,他引:1
T Sampei M Mizuno S Nakajima A Suzuki H Hadeishi T Ishikawa N Yasui 《No shinkei geka. Neurological surgery》1991,19(9):825-830
Twenty-five cases of patients with growing up aneurysms are reported. Growth of the aneurysm was confirmed by repeated angiography within 1 month in 11 cases (short-term group), and for over 1 month in the other 14 cases (long-term group) following the initial angiography. Clinical history, shape and growth pattern of aneurysms, as well as hemodynamic factors that effect the growth were investigated in each group. The aneurysms were classified according to the shape into dome-type (smooth contour) and bleb-type (irregular contour). In all cases of the short-term group, the first angiography was performed because of rupture of the aneurysm. In this group, 4 cases bled again because of enlargement or the development of an aneurysmal bleb. Growth rate and the initial size of the aneurysm did not effect the potential of re-rupture. In the long-term group, 9 cases out of 14 (64.3%) had "non-ruptured aneurysm" at the time of first angiography. In the follow up, 5 cases were ruptured (two because of re-bleeding and three for the first time). In 3 out of these 5 cases, a bleb was demonstrated on initial angiography, and in another case, a bleb was demonstrated in follow-up angiography. Only one case ruptured because of the growth of the aneurysmal dome. Most of the aneurysms that rupture, in the follow-up survey, showed a larger growth rate in comparison with aneurysms that did not rupture. Many cases of this long-term group were associated with hypertension or vascular abnormalities which would effect the aneurysmal growth.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
69.
Chronological changes in nonhaemorrhagic brain Infarcts with short T1 in the cerebellum and basal ganglia 总被引:2,自引:0,他引:2
Our purpose was to investigate nonhaemorrhagic infarcts with a short T1 in the cerebellum and basal ganglia. We carried out
repeat MRI on 12 patients with infarcts in the cerebellum or basal ganglia with a short T1. Cerebellar cortical lesions showed
high signal on T1-weighted spin-echo images beginning at 2 weeks, which became prominent from 3 weeks to 2 months, and persisted
for as long as 14 months after the ictus. The basal ganglia lesions demonstrated slightly high signal from a week after the
ictus, which became more intense thereafter. Signal intensity began to fade gradually after 2 months. High signal could be
seen at the periphery until 5 months, and then disappeared, while low or isointense signal, seen in the central portion from
day 20, persisted thereafter.
Received: 1 February 1999 Accepted: 13 September 1999 相似文献
70.