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261.
上周 ,在卡塔尔多哈举行的世界贸易组织部长会议上 ,来自该组织 142个成员国政府的世贸领导 ,重点讨论了目前严重存在的医疗保健问题。贸易部长们就其成员国为保护公共健康而必须采取措施的紧急情况下 ,如果灵活掌握该组织关于知识产权的贸易相关协定 (TRIPS) ,展开了辩论。明确了这种灵活性对于发展中国家至关重要 ,因为它可以使那些遭受HIV/艾滋病以及其他危及生命疾病的数百万贫困人群 ,改善其获得基本药品和负担所需费用的可能性。但基本药物的使用权并非是受全球贸易规定影响的唯一医疗保健问题。世界贸易组织的各项协议还会形… 相似文献
262.
Oestradiol and progesterone profiles from naturally occurringconception and exposed non-conception cycles were compared toassess the impact of natural variation in concentrations ofovarian steroid hormones on female fecundity. In a prospective,longitudinal study, 24 women collected saliva samples twicedaily and recorded intercourse for up to 1 year or until a pregnancywas clinically confirmed. Oestradiol and progesterone concentrationswere measured by a salivary radioimmunoassay. Average mid-follicularoestradiol concentrations were significantly higher in conceptionthan in non-conception cycles (12.6±1.7 versus 8.5±0.6pmol/1, P<0.01). A separate analysis, including only cyclesfrom those women who contributed both conception and non-conceptioncycles, demonstrated an even more pronounced difference in mid-follicularoestradiol concentrations, not just for conception and non-conceptioncycles as groups (14.5±2.3 versus 6.5±0.7 pmol/1,P<0.001), but also between the conception and average non-conceptionconcentrations of individual women. Among these women, relativemid-follicular oestradiol concentration was highly correlatedwith the probability of successful conception. In addition,relative body weight was significantly positively correlatedwith mid-follicular oestradiol concentration. These findingsindicate that variation in follicular development, reflectedin variation in follicular oestradiol concentrations, is animportant indicator of fecundity. 相似文献
263.
The health and adjustment of Iranian immigrants. 总被引:1,自引:0,他引:1
J G Lipson 《Western journal of nursing research》1992,14(1):10-24; discussion 24-9
264.
Hereditary hemolytic anemia caused by diverse point mutations of pyruvate kinase gene found in Japan and Hong Kong 总被引:2,自引:1,他引:1
Kanno H; Wei DC; Chan LC; Mizoguchi H; Ando M; Nakahata T; Narisawa K; Fujii H; Miwa S 《Blood》1994,84(10):3505-3509
We identified four distinct point mutations in homozygous pyruvate kinase (PK) variants in Japanese and Chinese patients with chronic nonspherocytic hemolytic anemia. All gene abnormalities were missense mutations that caused single amino acid substitutions. 1261A (Q421K) and 1436A (R436H), which were identified in PK Sendai and PK Shinshu, had been found in unrelated Japanese and Amish PK variants, respectively. The clinical severity and extremely low residual erythrocyte PK activity of PK Shinshu as well as of the Amish PK might be caused partly by aberrant splicing, because the 1436A mutation changes a nucleotide at the last nucleotide in the exon 10. Recently, we diagnosed a 42-year-old Japanese woman with chronic nonspherocytic hemolytic anemia as having a homozygous PK deficiency. DNA sequencing of the variant PK gene showed a homozygous missense mutation at 1403GCT- ->GTT, resulting in a single amino acid substitution from 468la-->Val. The gene mutation is likely to impair the allostericity of this enzyme, speculated from the tertiary structure. A homozygous missense mutation in PK Hong Kong, a boy of a non-Han southern Chinese minority group, was identified in exon 7 of the human L-PK gene, 941ATT-->ACT, resulting in a single amino acid substitution from 314lle-->Thr. The R- PK activity is expected to be severely affected, because the mutated amino acid residue is located between the 313 Lys and the 315 Glu, which are very important for acid-base catalysis and magnesium binding, respectively. Both the R- and M2-type PK were shown by polyacrylamide gel electrophoresis of the PK Hong Kong erythrocyte lysate, and this is the first report of a homozygous individual whose erythrocytes contain the immature (M2)-type isozyme. 相似文献
265.
JI Tang TP Shakespeare JJ Lu YH Chan KM Lee LC Wong RK Mukherjee MF Back 《Journal of Medical Imaging and Radiation Oncology》2008,52(5):497-502
The palliative radiotherapeutic management of unresectable non‐small‐cell lung cancer is controversial, with various fractionation (Fx) schedules available. We aimed to determine patient’s choice of Fx schedule after involvement in a decision‐making process using a decision board. A decision board outlining the various advantages and disadvantages apparent in the Medical Research Council study of Fx schedules (17 Gy in two fractions vs 39 Gy in 13 fractions) was discussed with patients who met Medical Research Council eligibility criteria. Patients were then asked to indicate their preferred Fx schedules, reasons and their level of satisfaction with being involved in the decision‐making process. Radiation oncologists (RO) could prescribe radiotherapy schedules irrespective of patients’ preferences. Of 92 patients enrolled, 55% chose the longer schedule. English‐speaking patients were significantly more likely to choose the longer schedule (P = 0.02, 95% confidence interval: 1.2–7.6). Longer Fx was chosen because of longer survival (90%) and better local control (12%). Shorter Fx was chosen for shorter overall treatment duration (80%), cost (61%) and better symptom control (20%). In all, 56% of patients choosing the shorter schedule had their treatment altered by the treating RO, whereas only 4% of patients choosing longer Fx had their treatment altered (P < 0.001). Despite this, all (100%) patients were satisfied with being involved in the decision‐making process. The decision board was useful in aiding decision‐making, with both Fx schedules being acceptable to patients. Interestingly, despite the longer average survival associated with longer Fx, nearly half of the patients believed that this was not as important as a shorter duration of treatment and lower cost. Despite patients’ preferences, there were significant alterations of preferred schedules because of RO’s own biases. 相似文献
266.
David A Lipson David A Roberts John Hansen-Flaschen Thomas R Gentile Gordon Jones Alan Thompson Ivan E Dimitrov Harold I Palevsky John S Leigh Mitchell Schnall Rahim R Rizi 《Magnetic resonance in medicine》2002,47(6):1073-1076
Conventional nuclear ventilation/perfusion (V/Q) scanning is limited in spatial resolution and requires exposure to radioactivity. The acquisition of pulmonary V/Q images using MRI overcomes these difficulties. When inhaled, hyperpolarized helium-3 ((3)He) permits MRI of gas distribution. Magnetic labeling of blood (arterial spin-tagging (AST)) provides images of pulmonary perfusion. Three normal subjects, two patients who had undergone single lung transplantation for emphysema, and one subject with pulmonary embolism (PE), were imaged. (3)He distribution and blood perfusion appeared uniform in the normal subjects and throughout the lung allografts. Gas distribution and perfusion in the emphysematous lungs were non-uniform and paralleled radiographic abnormalities. AST imaging alone revealed a lower-lobe wedge-shaped perfusion defect in the patient with PE that corresponded to computed tomography (CT) imaging. Hyperpolarized (3)He gas is demonstrated to provide ventilation images of the lung. Blood perfusion information may be obtained during the same examination using the AST technique. The sequential application of these imaging methods provides a novel tool for studying V/Q relationships. 相似文献
267.
Lipson M 《Explore (New York, N.Y.)》2005,1(4):306-307
If the issues of communication, timing and truth-telling in all the stages of life continue to present some of the most thoughtful challenges in a clinician's practice, this is especially true in end of life care. Michael Lipson's narrative of a child's death and his subsequent dual reflections on truth and the eternal fill me with a burning question. Why wait for "Sister Death" to arrive to live with this kind of presence-of-being? This expansion "beyond?" Wouldn't it deepen and enrich our lives to live with this awareness or capacity right now? -Therese Schroeder-Sheker, The Chalice of Repose Project. 相似文献
268.
End-stage liver disease as a consequence of hepatic sarcoidosis is a rare indication for liver transplantation. Consequently, there is a paucity of information on the pre-transplant findings and post-operative course of individuals transplanted for hepatic sarcoidosis. The purpose of this study was to evaluate our experience with liver transplantation for sarcoidosis. Cases were identified by review of the Mount Sinai Hospital liver transplant database. For each case, two control patients with other causes of liver failure matched for age, gender and date of transplant were selected for comparison. Hepatic sarcoidosis was the indication for liver transplantation in only seven of 2117 (0.3%) adult transplants performed from September 1988 to June 2004. The diagnosis of sarcoidosis was established by findings of extensive, non-caseating granulomas in pre-transplant liver biopsy specimens or in the native liver explant. Extrahepatic disease was limited to pulmonary involvement in four patients. Sarcoid cases were statistically more likely to have diabetes mellitus (100% vs. 21%, p = 0.001) and less likely to have antibodies to hepatitis C (0% vs. 50%, p = 0.047). Rates of acute cellular rejection were 57% in cases and 36% in controls (p = 0.397). Hepatic granulomas were identified in one patient at 5.6 yr of follow-up. Among cases, the 1-yr graft and patient survival rates were 100% and 5-yr graft and patient survival rates were 86%. The 1- and 5-yr graft and patient survival rates were comparable with those of patients transplanted for other indications. 相似文献
269.
Neurotrophic properties of olfactory ensheathing glia 总被引:40,自引:0,他引:40
Olfactory ensheathing cells (OEC) constitute a specialized population of glia that accompany primary olfactory axons and have been reported to facilitate axonal regeneration after spinal cord injury in vivo. In the present report we describe OEC neurotrophic factor expression and neurotrophic properties of OECs in vitro. Investigation of the rat olfactory system during development and adulthood by radioactive in situ hybridization revealed positive labeling in the olfactory nerve layer for the neurotrophic molecules S-100beta, CNTF, BMP-7/OP-1, and artemin, as well as for the neurotrophic factor receptors RET and TrkC. Ribonuclease protection assay of cultured OEC revealed expression of NGF, BDNF, GDNF, and CNTF mRNA, while NT3 and NT4 mRNA were not detectable. In vitro bioassays of neurotrophic activity involved coculturing of adult OEC with embryonic chick ganglia and demonstrated increased neurite outgrowth from sympathetic, ciliary, and Remak's ganglia. However, when culturing the ganglia with OEC-conditioned medium, neurite outgrowth was not stimulated to any detectable extent. Our results suggest that the neurotrophic properties of OEC may involve secretion of neurotrophic molecules but that cellular interactions are crucial. 相似文献
270.
Multiple chemical sensitivities (MCS) is an acquired condition in which exposure to low levels of chemicals causes symptoms in multiple organ systems. Some 12%-16% of the U.S. population has some level of chemical sensitivity, 80% of whom are women. Attempts to reduce chemical exposures leads to enormous life difficulties at home, school, and workplace. We base our article on an ethnographic study of MCS in the United States and Canada. We describe here themes related to work issues in terms of a general trajectory of becoming sick from work exposures, coping with toxic physical environments and dealing with coworkers and, when unable to continue working, applying for workers' compensation, or disability status, or both. 相似文献