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91.
E. Sumner 《Annals of the Royal College of Surgeons of England》1975,56(2):81-88
A review is presented of the more recent biochemical findings in the hepatic porphyrias. The clinical aspects of acute porphyria are re-emphasized and illustrated with a case history. In particular the differentiation between porphyria and surgical causes of abdominal pain is stressed. The anaesthetic management is discussed and details of diagnostic and screening tests are given. 相似文献
92.
England JD Gronseth GS Franklin G Miller RG Asbury AK Carter GT Cohen JA Fisher MA Howard JF Kinsella LJ Latov N Lewis RA Low PA Sumner AJ;American Academy of Neurology;American Association of Electrodiagnostic Medicine;American Academy of Physical Medicine Rehabilitation 《Neurology》2005,64(2):199-207
The objective of this report was to develop a case definition of distal symmetric polyneuropathy to standardize and facilitate clinical research and epidemiologic studies. A formalized consensus process was employed to reach agreement after a systematic review and classification of evidence from the literature. The literature indicates that symptoms alone have relatively poor diagnostic accuracy in predicting the presence of polyneuropathy; signs are better predictors of polyneuropathy than symptoms; and single abnormalities on examination are less sensitive than multiple abnormalities in predicting the presence of polyneuropathy. The combination of neuropathic symptoms, signs, and electrodiagnostic findings provides the most accurate diagnosis of distal symmetric polyneuropathy. A set of case definitions was rank ordered by likelihood of disease. The highest likelihood of polyneuropathy (useful for clinical trials) occurs with a combination of multiple symptoms, multiple signs, and abnormal electrodiagnostic studies. A modest likelihood of polyneuropathy (useful for field or epidemiologic studies) occurs with a combination of multiple symptoms and multiple signs when the results of electrodiagnostic studies are not available. A lower likelihood of polyneuropathy occurs when electrodiagnostic studies and signs are discordant. For research purposes, the best approach to defining distal symmetric polyneuropathy is a set of case definitions rank ordered by estimated likelihood of disease. The inclusion of this formalized case definition in clinical and epidemiologic research studies will ensure greater consistency of case selection. 相似文献
93.
In the year 2000, approximately 330,000 people in the UK had been diagnosed with type 1 diabetes (Williams and Pickup, 2000), and this number is growing yearly. It is usually diagnosed in children and young adults although it can occur at any age. The onset of diabetes is usually sudden and results from destruction of the insulin-producing cells of the pancreas leading to a total loss of insulin secretion. Insulin injections and dietary modification are necessary treatments after diagnosis. Some patients find these changes difficult--a case study used in this article Illustrates the challenges they face. 相似文献
94.
Stellate ganglion (SG) neurons provide the main sympathetic innervation to the heart and help to regulate cardiac function. The purpose of this study was to determine if ultrasound imaging could be employed to retrograde label rat SG neurons innervating the heart without employing thoracotomy. In addition, electrophysiological experiments were performed to characterize the modulation of Ca(2+) channels by neurotransmitters in unlabeled and dye-labeled SG neurons. Fluorescence imaging of actutely isolated cells revealed that dye uptake was successful within five days following injection of dye in the cardiac muscle. Whole-cell voltage-clamp recordings revealed that the majority of the Ca(2+) current was carried by N-type Ca(2+) channels. Finally, fluorescence dye uptake did not appear to affect the modulation of Ca(2+) currents following exposure of SG neurons to norepinephrine, adenosine and neurokinin A. These results demonstrate that ultrasound imaging-guided percutaneous injection can be effectively employed to retrograde label neurons innervating the heart. 相似文献
95.
Fresh fruits and vegetables have been increasingly associated with outbreaks of foodborne illness. Microorganisms on the surface of raw produce may be difficult to remove for decontamination or microbial sampling due to entrapped or attached cells and porous surfaces. The objective of this study was to determine if ultrasonic treatment using 40 kHz with varying temperatures and agitation times can enhance removal and recovery of Salmonella spp. from raw produce surfaces. Strawberry, apple, and cantaloupe surfaces were spot inoculated with a fivestrain cocktail of nalidixic acid-resistant Salmonella spp. Produce were immersed in 0.1% buffered peptone water in either a Whirl-Pak bag for manual shaking (60 sec) or a sterile beaker for ultrasonic treatment (60 or 120 sec). Diluent temperatures of either 25 degrees C or 40 degrees C were used with these sampling protocols. Diluents were spiral plated onto tryptic soy agar supplemented with 50 ppm of nalidixic acid. No significant differences were observed between each Salmonella recovery method for each produce type. In this study, ultrasonic treatment using 40 kHz did not enhance recovery of Salmonella spp. from produce surfaces. The ultrasonic frequency, temperatures, and times used in this study did not enhance or diminish bacterial recovery. Additional research is still needed to determine the efficacy of other ultrasonic frequencies, diluents, and diluent temperatures for enhancing the recovery and enumeration of Salmonella spp. and other microorganisms from raw produce surfaces. 相似文献
96.
Utility assessment among patients with dry eye disease 总被引:11,自引:0,他引:11
PURPOSE: To determine utilities (patient preferences) for dry eye disease. DESIGN: Survey study. PARTICIPANTS: Fifty-six patients with mild, moderate, or severe dry eye treated by ophthalmologists in the Eye Care Services department of Henry Ford Health Care System. TESTING: Patients completed interactive software utility assessment questionnaires by the time trade-off (TTO) method. Utility scores were scaled such that a score of 1.0 = perfect health and 0 = death. Dry eye severity was independently classified using clinical parameters and physician/patient assessments. Global health status, visual functioning, and ocular symptoms were assessed by the Short Form-36 Health Survey, 25-Item National Eye Institute Visual Function Questionnaire (NEI VFQ-25), and Ocular Surface Disease Index survey instruments. MAIN OUTCOME MEASURES: Utility scores for a range of dry eye severity states. These utilities were compared with utilities reported for other disease states. Correlations with the general and vision-related health status measures were conducted. RESULTS: Fifty-six patients completed the utility assessments with acceptable reliability. Mean utilities for moderate (0.78) and severe dry eye (0.72) by TTO were similar to historical reports for moderate (0.75) and more severe (class III/IV) angina (0.71), respectively. Utility scores correlated with the NEI VFQ-25 composite score (rho = 0.32; P = 0.037) and with components of other health measures. CONCLUSIONS: Utilities for the more severe forms of dry eye are in the range of conditions like class III/IV angina (0.71) that are widely recognized as lowering health utilities. Our results underscore how significantly dry eye impacts patients compared with other medical conditions. 相似文献
97.
Prasad SR Saini S Sumner JE Hahn PF Sahani D Boland GW 《Journal of computer assisted tomography》2003,27(3):380-384
PURPOSE: Radiologic assessment of "response-to-treatment" during clinical trials of anticancer drugs has been conventionally based on bidirectional tumor measurement. Recently, the revised guidelines were published, which recommended unidirectional tumor measurements. The purpose of this study was to compare response to treatment between the two measurement techniques in breast cancer patients with lung and liver metastases. METHOD: Contrast-enhanced computed tomography studies of 86 breast cancer patients who had lung (n = 27) and liver (n = 59) metastases and who were enrolled in a phase-III oncology trial were evaluated before initiation of treatment and at 6 months after treatment. Lesions were measured by subspecialist radiologists on digitized images using electronic calipers. The largest diameter of the lesions was extracted from bidimensional measurements. Response to treatment was categorized into one of four categories: complete response indicating lesion disappearance, partial response indicating >30% decrease in tumor diameter, or >50% reduction in tumor area, disease progression indicating >20% increase in tumor diameter, or >25% increase in tumor area, and stable disease (neither complete response, partial response, nor disease progression). Response to treatment between the two measurement techniques was compared statistically using the chi2 test. RESULTS: Response to treatment was concordant in 76 patients between unidimensional and bidimensional measurement techniques. In 5 patients (2 lung and 3 liver metastases) the response assessment was improved using unidimensional criteria and in 5 patients (2 lung and 3 liver metastases) the response was worse using unidimensional guidelines. Thus, the overall response rate was 50% for both unidimensional and bidimensional measurement techniques. There was no statistical difference between the two techniques. CONCLUSION: Unidimensional measurements are appropriate for measuring the size of liver and lung metastases for determining response to treatment during clinical testing of oncologic drugs. 相似文献
98.
OBJECTIVE: To determine if the presence of early radiographic signs of degenerative changes in the hip is associated with the pattern of bone mineral density (BMD) in the proximal femur. METHODS: Twenty-eight patients scheduled for unilateral hip replacement were placed into one of 2 groups based on the preoperative radiographic findings in the asymptomatic hip: Group 1 (no changes) or Group 2 (doubtful or minimal changes). Both femora and the lumbar spine were scanned by dual energy x-ray absorptiometry. RESULTS: The BMD z scores of the asymptomatic hip were significantly higher at the neck and Ward's triangle sites in Group 2 compared to Group 1 (p < 0.05). There were no differences between the groups in the symptomatic hip except at Ward's triangle, where Group 2 had higher z scores than Group 1 (p < 0.05). The lumbar BMD z scores were elevated in both groups (p < 0.05). CONCLUSION: Proximal femur BMD in the asymptomatic hip of patients scheduled for unilateral hip replacement is elevated when there are early radiographic signs of hip osteoarthritis (OA), consistent with the idea that early OA involves bone as well as cartilage. 相似文献
99.
Styrene oxide in blood, hemoglobin adducts, and urinary metabolites in human volunteers exposed to (13)C(8)-styrene vapors 总被引:2,自引:0,他引:2
Johanson G Ernstgård L Gullstrand E Löf A Osterman-Golkar S Williams CC Sumner SC 《Toxicology and applied pharmacology》2000,168(1):36-49
Styrene is used in the manufacture of plastics and polymers and in the boat-building industry. The major metabolic route for styrene in rats, mice, and humans involves conversion to styrene-7,8-oxide (SO). The purpose of this study was to evaluate blood SO, SO-hemoglobin (SO-Hb) adducts, and urinary metabolites in styrene-exposed human volunteers and to compare these results with data previously obtained for rodents. Four healthy male volunteers were exposed for 2 h during light physical exercise to 50 ppm (13)C(8)-styrene vapor via a face mask. Levels and time profiles of styrene in exhaled air, blood, and urine (analyzed by GC) and urinary excretion patterns of mandelic acid and phenylglyoxylic acid in urine (analyzed by HPLC) were comparable to previously published volunteer studies. Maximum levels of SO in blood (measured by GC-MS) of 2.5-12.2 (average 6.7) nM were seen after 2 h, i.e., in the first sample collected after exposure had ended. The styrene blood level in humans was about 1.5 to 2 times higher than in rats and 4 times higher than in mice for equivalent styrene exposures. In contrast the SO levels in human blood was approximately fourfold lower than in mice. The level of hydroxyphenethylvaline (determined by GC-MS-MS) in pooled blood collected after exposure was estimated as 0.3 pmol/g globin corresponding to a SO-Hb adduct increment of about 0.003 pmol/g and ppmh. NMR analyses of urine showed that a major portion (> 95%) of the excreted (13)C-derived metabolites was derived from hydrolysis of SO, while only a small percentage of the excreted metabolites (< 5%) was derived from metabolism via phenylacetaldehyde. Signals consistent with metabolites derived from other pathways of styrene metabolism in rodents (such as glutathione conjugation with SO or ring epoxidation) were not detected. 相似文献
100.