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51.
52.
Saadat P. Cesnorek S. Ram R. 《世界核心医学期刊文摘》2006,2(8):47-48
神经节细胞瘤是一种神经内分泌肿瘤,其发生与自主神经系统的交感或副交感神经节有关。罕见发生于膀胱、前列腺和子宫。本文作者报道1例发生于儿童头皮的原发性皮肤神经节细胞瘤。对此肿瘤进行了组织学、免疫组化和超微结构研究。该病例可能代表神经嵴细胞向鳃弓发育过程中的一种异常迁移。此外,研究结果还强调在胚胎发育过程中神经嵴和鳃弓/裂之间有复杂的相互作用。 相似文献
53.
Objective : Understanding patients' and their parents' perceptions towards asthma medication is important in developing strategies to ensure patient compliance. In this study, parents' perceptions towards their children's use of inhaled medication for asthma treatment were evaluated.
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
54.
Objective : To assess the relationship between the subtypes of hypertension in pregnancy and subsequent neonatal haematology.
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
55.
The glutathione S-transferase mu polymorphism and susceptibility to acute lymphocytic leukemia 总被引:6,自引:0,他引:6
It has been postulated that the absence of glutathione S-transferase mu (GSTmu), which impairs detoxification of some carcinogens, might predispose some individuals to the development of certain cancers. In the present study, polymorphism of GSTM1 were detected by polymerase chain reaction (PCR) in 38 patients with acute lymphocytic leukemia and 75 normal subjects. The null genotype of GSTM1 was significantly more common among leukemic patients compared with the normal control group (55.3 vs. 32.0%; P<0.025). The absence of the GSTmu enzyme may increase the risk of the development of leukemia. 相似文献
56.
Rationale Administration to rats of a neurotoxic dose of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) produces an impairment in thermoregulation which is reflected in a prolonged hyperthermic response to a subsequent dose of MDMA given to rats housed at high ambient temperature.Objective We wished to examine whether the impaired thermoregulation was associated with decreased cerebral 5-HT content produced by the prior neurotoxic dose of MDMA.Methods Rats were injected with drugs decreasing 5-HT function [the tryptophan hydroxlase inhibitor p-chlorophenylalanine (PCPA), and 5-HT receptor antagonists] and rectal temperature was measured after administering MDMA to rats housed at 30°C.Results PCPA pretreatment decreased 5-HT and 5-HIAA concentrations in cortex, hippocampus and striatum by >80% and prolonged the hyperthermia induced in rats housed at 30°C by administering MDMA (5 mg/kg i.p.). A similar prolongation of the hyperthermic response to MDMA was seen when rats were pretreated with methysergide (10 mg/kg i.p.) or the 5-HT1A antagonist WAY100635 (0.5 mg/kg s.c.).Conclusions Decreasing 5-HT function in diverse ways enhanced the hyperthermic response to MDMA given to rats housed at high ambient temperature. This suggests that loss of 5-HT acting on 5-HT1A receptors leads to impaired thermoregulation in rats and suggests that the impairment seen in MDMA pretreated rats housed at high ambient temperature is due to a loss in 5-HT function. These data could have implications for recreational users of MDMA, who may have damaged serotoninergic neurons because of prior heavy or frequent use of the drug, when taking further doses of MDMA in hot environments such as dance clubs. 相似文献
57.
Development of a new access device for transgastric surgery 总被引:10,自引:0,他引:10
Lee?L.?SwanstromEmail author Richard?Kozarek Pankaj?J.?Pasricha Steven?Gross Desmond?Birkett Per-Ola?Park Vahid?Saadat Richard?Ewers Paul?Swain 《Journal of gastrointestinal surgery》2005,9(8):1129-1137
Flexible endoscope-based endoluminal and transgastric surgery for cholecystectomy, appendectomy, bariatric, and antireflux
procedures show promise as a less invasive form of surgery. Current endoscopes and instruments are inadequate to perform such
complex surgeries for a variety of reasons: they are too flexible and are insufficient to provide robust grasping and anatomic
retraction. The lack of support for a retroflexed endoscope in the peritoneal cavity makes it hard to reach remote structures
and makes vigorous retraction of tissues and organs difficult. There is also a need for multiple channels in scopes to allow
use of several instruments and to provide traction/countertraction. Finally, secure means of tissue approximation are critical.
The aim was to develop and test a new articulating flexible endoscopic system for endoluminal and transgastric endosurgery.
A multidisciplinary group of gastrointestinal physicians and surgeons worked with medical device engineers to develop new
devices and instruments. Needs assessments and design parameters were developed by consensus. Prototype devices were tested
using inanimate models until usable devices were arrived at. The devices were tested in nonsurvival pigs and dogs. The devices
were accessed through an incision in the wall of the stomach and manipulated in the peritoneal cavity to accomplish four different
tasks: right upper quadrant wedge liver biopsy, right lower quadrant cecal retraction, left lower quadrant running small bowel,
and left lower quadrant exposure of esophageal hiatus. In another three pigs, transgastric cholecystectomy was attempted.
The positions of the device, camera, and endosurgical instruments, with and without ShapeLock technology, were recorded using
laparoscopy and endoscopy and procedure times and success rates were measured. Instrument design parameters and their engineering
solutions are described. Flexible multilumen guides which could be locked in position, including a prototype which allowed
triangulation, were constructed. Features of the 18-mm devices include multidirectional mid body and/or tip angulation, two
5.5-mm accessory channels allowing the use of large (5-mm) flexible endosurgical instruments, as well as a 4-mm channel for
an ultraslim prototype video endoscope (Pentax 4 mm). Using the resulting devices, the four designated transgastric procedures
were performed in anesthetized animals. One hundred percent of the transgastric endosurgical procedures were accomplished
with the exception of a 50% success for hiatal exposure, a 90% success rate for wedge liver biopsy, and a 33.3% success rate
for cholecystectomy. A new endosurgical multilumen device and advanced instrumentation allowed effective transgastric exploration
and procedures in the abdominal cavity including retraction of the liver and stomach to allow exposure of the gallbladder,
retraction of the cecum, manipulation of the small bowel, and exposure of the esophageal hiatus. This technology may serve
as the needed platform for transgastric cholecystectomy, gastric reduction, fundoplication, hiatus hernia repair, or other
advanced endosurgical procedures.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation).
Partially funded and supported by USGI Medical, San Clemente, California. 相似文献
58.
Kain ZN Caldwell-Andrews AA Weinberg ME Mayes LC Wang SM Gaal D Saadat H Maranets I 《Anesthesiology》2005,102(4):720-726
BACKGROUND: The authors conducted a double-blind, randomized, controlled trial to determine whether the use of sevoflurane in children undergoing anesthesia and surgery results in a higher incidence of postoperative maladaptive behavioral changes as compared with halothane. METHODS: Children and their parents (n = 102) were randomly assigned to either a halothane group (n = 50) or a sevoflurane group (n = 52). The intraoperative anesthetic protocol was strictly controlled, and the postoperative analgesic consumption and pain levels were recorded. The effect of the group assignment on emergence status and maladaptive postoperative behavioral changes was assessed both by validated psychological measures and physiologic instruments (actigraphy) on postoperative days 1-7. Anxiety of the parent and child was also assessed, as was the child's postoperative recovery (Recovery Inventory). RESULTS: There were no group differences in preoperative state anxiety, postoperative analgesic requirements, postoperative pain, or the incidence of emergence delirium (P = not significant). Two-way repeated-measures analysis of variance showed no group differences in the incidence of postoperative maladaptive behaviors (F4,72 = 0.60, P = 0.701) or actigraphic variables such as percent sleep, number of night awakenings, and night awakenings that lasted for more than 5 min (P = not significant). CONCLUSION: The authors found no increased incidence of emergence delirium, maladaptive postoperative behavior changes, or sleep disturbances in children undergoing anesthesia with sevoflurane as compared with halothane. 相似文献
59.
To identify whether the polymorphisms of glutathione S-transferase M1 (GSTM1) and GSTT1 genes predict a high-tended risk of using tobacco, the GSTM1 and GSTT1 genotypes of 369 Iranian males (254 nonsmokers and 115 smokers) and 314 Iranian females (245 nonsmokers and 69 smokers) were determined. The frequencies of GSTM1 (males: OR=0.98, 95% CI=0.62-1.57, P=.974; females: OR=1.34, 95% CI=0.75-2.39, P=.358) and GSTT1 (males: OR=1.25, 95% CI=0.76-2.04, P=.412; females: OR=0.84, 95% CI=0.46-1.51, P=.626) null genotypes were similar in nonsmokers and smokers. The risk of being a smoker was to be equally frequent in each combination of the genotypes. The present results revealed that there was no difference between smokers and nonsmokers for these two genetic polymorphisms. 相似文献
60.
Sanchez V O'shea E Saadat KS Elliott JM Colado MI Green AR 《Journal of psychopharmacology (Oxford, England)》2004,18(3):412-416
The technique of 'binge' dosing (several doses in one session) by recreational users of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) requires evaluation in terms of its consequences on the acute hyperthermic response and long-term neurotoxicity. We examined the neurotoxic effects of this dosing schedule on 5-HT and dopamine neurones in the rat brain. When repeated (three) doses of MDMA (2, 4 and 6 mg/kg i.p.) were given 3 h apart to rats housed at 19 degrees C, a dose-dependent acute hyperthermia and long-term loss of 5-HT was observed in several brain regions (hippocampus, cortex and striatum), with an approximate 50% loss following 3 x 4 mg/kg and 65% decrease following 3 x 6 mg/kg. No decrease in striatal dopamine content was detected. When MDMA (4 mg/kg i.p.) was given repeatedly to rats housed at 30 degrees C, a larger acute hyperthermic response than that observed in rats treated at 19 degrees C environment was seen (maximum response 2.6 +/- 0.1 degrees C versus 1.3 +/- 0.2 degrees C). A long-term cerebral 5-HT loss of approximately 65% was also detected in both the cortex and hippocampus, but no loss in striatal dopamine content occurred. These data emphasize the increased acute hyperthermic response and neurotoxicity which occurs when MDMA is administered in a hot room environment compared to normal room temperature conditions, and support the view that MDMA is a selective 5-HT neurotoxin, even when a binge dosing schedule is employed and the rats are present in a hot environment. 相似文献