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排序方式: 共有546条查询结果,搜索用时 15 毫秒
541.
Abnormal erythroid progenitor cells in human preleukemia 总被引:1,自引:2,他引:1
Ten patients with preleukemia were studied by the erythroid cell clonal culture technique. In nine of these patients, erythroid colonies derived from peripheral blood BFU-E were not observed, while the other patient had markedly decreased peripheral blood BFU-E-derived erythroid colonies in vitro. In three patients, marrow cells were also cultured and no BFU-E-derived erythroid colonies were detected. These studies indicate that immature erythroid progenitor cells, BFU-E, in patients with preleukemia are either markedly decreased in number or grossly defective in their proliferative or differentiative capacities. 相似文献
542.
K. B. BJÖRKELUND A. HOMMEL K.‐G. THORNGREN L. GUSTAFSON S. LARSSON D. LUNDBERG 《Acta anaesthesiologica Scandinavica》2010,54(6):678-688
Background: There is an evident need for improved management of elderly patients with trauma in order to avoid common and troublesome complications such as delirium. The aim of this study was to investigate whether an implementation of a multi‐factorial program including intensified pre‐hospital and perioperative treatment and care could reduce the incidence of delirium in elderly patients with hip fracture, cognitively intact at admission to the hospital. In addition, we explored the factors that characterize patients who developed delirium. Methods: A prospective, quasi‐experimental design was used. A total of 263 patients with hip fracture (≥65 years), cognitively intact at admission, were consecutively included between April 2003 and April 2004. On 1 October 2003, a new program was introduced. All patients were screened for cognitive impairment within 30 min after admission to the emergency department using The Short Portable Mental Status Questionnaire (SPMSQ). To screen for delirium, patients were tested within 4 h of admission and thereafter daily, using the Organic Brain Syndrome scale. Results: The number of patients who developed delirium during hospitalization was 74 (28.1%), with a decrease from 34% (45 of 132) in the control group to 22% (29 of 131) in the intervention group (P=0.031). Patients who developed delirium were statistically older, more often had >4 prescribed drugs at admission and scored less well in the SPMSQ test. Conclusion: The use of a multi‐factorial intervention program in elderly hip fracture patients, lucid at admission, reduced the incidence of delirium during hospitalization by 35%. 相似文献
543.
Low-dose Cyclopenthiazide in the Treatment of Hypertension: A One-year Community-based Study 总被引:1,自引:0,他引:1
JOHNSTON GD; WILSON R; MCDERMOTT BJ; MCVEIGH GE; DUFFIN D; LOGAN J 《QJM : monthly journal of the Association of Physicians》1991,78(2):135-143
After an 8-week placebo period, 73 patients whose diastolicblood pressures were between 90 and 110 mmHg were randomly assignedto receive 125 µg (low dose) or 500 µg of cyclopenthiazide(standard dose) for a period of one year. Blood pressure wasmeasured in the patient's home by the same observer at two-weeklyintervals during an 8-week placebo run-in period, every 4 weeksfor a further 12 weeks and at 24, 36 and 52 weeks thereafter.Serum potassium, urate, glucose, glycosylated haemoglobin, totaland HDL cholesterol, and apolipoproteins were measured at theend of the placebo period and at 4, 8, 24 and 52 weeks of activetreatment. Twelve of the 73 patients had an inadequate antihypertensiveresponsefive on the higher dose and seven on the lowerdose. One patient receiving 500 µg was withdrawn becauseof adverse effects. In the remaining 60 patients, systolic anddiastolic blood pressures were significantly reduced when comparedwith pretreatment values in both treatment groups throughoutthe one year period. The decreases in blood pressure were notsignificantly different from each other (p>0.65). Three patientson 500 µg required potassium supplements. Maximum decreasesin the serum potassium of 0.52 mmol/l(500 µg dose) and0.14 mmol/l(125 µg dose) were observed at 24 weeks oftreatment in the remaining 57 patients. The differences betweenthe two doses at this time were statistically significant (p< 0·05), as were the increases in serum urate observedat 4, 8 and 24 weeks (p<0.05). Five hundred micrograms ofcyclopenthiazide increased total serum cholesterol at eightand 24 weeks (0.35, 0.36 mmol/l respectively) when comparedwith pretreatment values (p<0.01) and almost achieved statisticalsignificance when compared with the corresponding low dose value(p = 0.066). This study confirms that 125 µg of cyclopenthiazideis a useful antihypertensive agent with a favourable metabolicprofile which is maintained in the long term. 相似文献
544.
Serological confirmation of human T-lymphotropic virus type I infection in healthy blood and plasma donors 总被引:10,自引:0,他引:10
Anderson DW; Epstein JS; Lee TH; Lairmore MD; Saxinger C; Kalyanaraman VS; Slamon D; Parks W; Poiesz BJ; Pierik LT 《Blood》1989,74(7):2585-2591
We wished to develop criteria for serological confirmation of human T- lymphotropic virus type I (HTLV-I) infection in healthy donors. Selected serum or plasma samples reactive by HTLV-I enzyme immunosorbent assay or gel-agglutination assays with at least one viral- specific band on Western immunoblot (WIB) were tested in six laboratories by four WIBs and four radioimmunoprecipitation assays (RIPAs) for antibodies to HTLV-I proteins encoded by gag (p19 and p24), env (gp46 and/or gp61), and tax (p40x) genes. One hundred forty-two donor sera were obtained from 38 Japanese, 69 American, and 35 Caribbean blood or plasma donors. Among these samples, WIB assays appeared more sensitive to p24 antibodies, whereas RIPAs were significantly more sensitive to gp61 antibodies. All sera (137) with gp61 antibodies had p24 antibodies. Of the 137 sera positive for p24 and gp61 antibodies, p19 antibodies were detected in 129 sera, and p40x antibodies were detected in 108. In sera with p19 antibodies and antibodies to env- or tax-encoded proteins, p24 antibodies were always present. Antibodies to p40x were not found in the absence of gp61 antibodies. Virological evidence of infection was found in seven American donors by lymphocyte coculture (one HTLV-I, one HTLV-II) or by polymerase chain reaction (three HTLV-I, two HTLV-II). Sera from all seven donors showed p24 and gp46 and/or gp61 antibodies. We suggest that seroreactivity to both p24 and gp46 and/or gp61 by WIB or RIPA or both are suitable criteria to confirm but not to distinguish HTLV-I and HTLV-II infections. 相似文献
545.
Endometrial perfusion across the normal human menstrual cycle assessed by laser Doppler fluxmetry 总被引:1,自引:5,他引:1
This study investigated variations in microvascular perfusion of human
endometrium across the menstrual cycle, using a laser Doppler technique to
assess red blood cell (RBC) flux. Endometrial RBC flux was monitored by
laser Doppler fluxmetry via a fibre optic probe inserted transvaginally
into the uteri of 19 conscious normal volunteer women, on four occasions at
weekly intervals over one menstrual cycle. Regional variation in RBC flux
was investigated in 16 surgical patients under general anaesthesia and in
five excised uteri. Endometrial perfusion exhibited short-term temporal
variations consistent with the cardiac cycle and often also showed
vasomotion (5-12 cycles/min). Mean endometrial perfusion differed between
phases of the menstrual cycle in conscious women, being highest during
early proliferative and early follicular phases. There were no significant
regional differences in local mean endometrial perfusion in anaesthetized
patients. No evidence of endometrial ischaemia/reperfusion episodes was
found in any subject using this technique. This study provides benchmark
data of variations in RBC flux per unit volume of tissue in the luminal
approximately 1 mm of endometrium, across the normal human menstrual cycle.
Flux values were highest at times associated with endometrial growth and
preparation for implantation, indicating that RBC flux may be a useful
parameter for assessment of endometrial physiology.
相似文献
546.
Improved methods for the isolation and purification of porcine islets. 总被引:10,自引:0,他引:10
Recent progress in human islet transplantation demonstrates the feasibility of using purified human islets for treatment of type 1 diabetes mellitus; however, a shortage of human pancreata remains a major obstacle. This report describes methods to isolate porcine islets using a modification of the automated chamber method. The pancreata from 2-year-old sows were trimmed and injected intraductally with Sevac, Sigma, or Liberase PI collagenase. The pancreata was placed in the chamber, shaken, and recirculated at 70 ml/min until an adequate number of islets were liberated. The digest was centrifuged and the pellets pooled with University of Wisconsin Solution + 10% horse serum and incubated at 4 degrees C for 1 h. The islets were purified using a continuous gradient of Hypaque Euroficoll on a refrigerated COBE 2991. The islets were collected in fractions, assessed for purity, sized, and then suspended in Medium 199. Collagenase preparations obtained from Sevac (2919 islet equivalents [IE]/g), Sigma (2543 IE/g), and Liberase PI (2901 IE/g) gave similar results with 94%-95% purity. In summary, we report a successful method for efficient isolation and purification of porcine islets, yielding nearly 3000 IE/gm, with different collagenase products. 相似文献