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51.
G Bischof E Wenzl M Weinlich G Hamilton W Feil R Schiessel 《Wiener klinische Wochenschrift》1990,102(13):369-375
Intracellular pH (pHi) regulation is essential for basic functioning of the cell and activation of pHi regulatory mechanisms appears to be involved in the initial stage of cell division. Little is known about pHi regulation in human colonic carcinoma cells. We investigated SW-620 (CCL 227) cells, a cell-line derived from a human colonic adenocarcinoma. pHi changes were recorded by computer-assisted spectrofluorimetric monitoring of the pH-sensitive, fluorescent dye BCECF (2',7'-bis(carboxyethyl)- 5(6)carboxyfluorescein). Resting pHi in HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) buffered solution was 7.53 +/- 0.01. Intracellular acidification after an ammonium prepulse produced a pHi decline of 0.5 units and pHi returned to normal value in NaCl Ringer's. Both 1 mM amiloride and Na-free solution completely inhibited recovery for 8 minutes. This inhibition was reversible in NaCl Ringer's. Na-free solution led to a pHi decrease to 7.39 +/- 0.04 after 16 min, pHi was also lowered by 8 minute incubation of cells with 1 mM amiloride (7.40 +/- 0.02). In HCO3/CO2-buffered solution resting pHi was 7.42 +/- 0.01 (n = 35). Recovery from an acute acid load, induced by NH4 prepulse or switching from HEPES- to bicarbonate-buffered solution, was Na dependent, Cl independent, reversible and only partially blocked by 1 mM amiloride - pHi slowly recovered from 6.83 +/- 0.03 to 7.00 +/- 0.06 in 8 minutes. In the presence of amiloride and 200 microns H2DIDS (dihydro-4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid) pHi recovery was completely inhibited for 8 minutes. In Na-free solution pHi decreased from 7.44 +/- 0.04 to 7.29 +/- 0.03 within 8 minutes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
52.
53.
Jirecek S Wieser F Kurz C Albrecht A Nagele F Wenzl R 《Wiener klinische Wochenschrift》2000,112(6):276-280
Myoma is one of the most common benign diseases of the female genital tract. The surgical management of this entity has been altered over the last years from complete hysterectomy to conservative enucleation of the myomas. We retrospectively compared our data concerning laparoscopic or open myomectomies. Over a period of 2 years, we operated 207 myomas in 102 patients. Of this collective, 69 (67.6%) were operated on laparoscopically and 33 (32.4%) via an open approach. In both groups, the median number of myomas was 2 (1-7). The mean diameter of the largest myoma was 5.1 +/- 2.4 cm (laparoscopy) and 6.2 +/- 2.6 cm (laparotomy), respectively. The additive diameter of myomas was 7.7 +/- 5.1 cm (laparoscopy) and 9.8 +/- 4.1 cm (laparotomy), respectively. There was no relevant difference between the groups in terms of operating time and blood loss. Four (3.9%) laparoscopies had to be converted to an open approach. In three cases (2.9%) a laparoscopically assisted enucleation had to be performed, requiring a mini-laparotomy 4 to 5 cm in length. We encountered no severe complications. Given appropriate indication, laparoscopic myomectomy is an easy-to-perform and minimally invasive technique with a low complication rate. 相似文献
54.
Prevalence of cytomegalovirus antibody in hemophiliacs and homosexuals infected with human immunodeficiency virus type 1 总被引:1,自引:0,他引:1
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions. 相似文献
55.
Mycophenolate mofetil in patients with Crohn's disease 总被引:2,自引:0,他引:2
Peter Fickert M.D. Thomas Anton Hinterleitner M.D. Heimo Helmut Wenzl M.D. Berendt Winfred Aichbichler M.D. Wolfgang Petritsch M.D. 《The American journal of gastroenterology》1998,93(12):2529-2532
Objective: Intolerance to azathioprine is a rare but important problem in treating chronically active Crohn's disease. We performed this study to evaluate mycophenolate mofetil as an alternative immunosuppressive therapy for patients with Crohn's disease who did not tolerate azathioprine.
Methods: Four patients with highly active perianal Crohn's disease and two patients with chronically active, steroid-dependent Crohn's disease were included. All patients consumed 2 g/day of mycophenolate mofetil for a median of 8 months (range, 6–12 months). Disease activity was measured by the Perianal Crohn's Disease Activity Index in patients with perianal disease and by the Crohn's Disease Activity Index in patients with chronically active Crohn's disease.
Results: Azathioprine-induced side effects disappeared after the drug was discontinued. All patients improved during treatment with mycophenolate mofetil, as shown by a remarkable reduction in the respective clinical scores. Five patients showed no side effects during treatment with mycophenolate mofetil. After 4 months' treatment one patient developed diarrhea that was probably not due to mycophenolate mofetil.
Conclusions: Mycophenolate mofetil could be an alternative therapy to azathioprine in patients with Crohn's disease. 相似文献
Methods: Four patients with highly active perianal Crohn's disease and two patients with chronically active, steroid-dependent Crohn's disease were included. All patients consumed 2 g/day of mycophenolate mofetil for a median of 8 months (range, 6–12 months). Disease activity was measured by the Perianal Crohn's Disease Activity Index in patients with perianal disease and by the Crohn's Disease Activity Index in patients with chronically active Crohn's disease.
Results: Azathioprine-induced side effects disappeared after the drug was discontinued. All patients improved during treatment with mycophenolate mofetil, as shown by a remarkable reduction in the respective clinical scores. Five patients showed no side effects during treatment with mycophenolate mofetil. After 4 months' treatment one patient developed diarrhea that was probably not due to mycophenolate mofetil.
Conclusions: Mycophenolate mofetil could be an alternative therapy to azathioprine in patients with Crohn's disease. 相似文献
56.
The poor treatment prognosis for tumours with oxygen-deficient areas is usually attributed to the increased radioresistance of hypoxic cells. It can be expressed by the oxygen enhancement ratio (OER), which decreases with increasing linear energy transfer (LET) suggesting a potential clinical advantage of high-LET radiotherapy with heavy ion beams compared to low-LET photon or proton irradiation. The aim of this work is to review the experimental cell survival data from the literature and, based on them, to develop a simple OER model to estimate the clinical impact of OER variations. For this purpose, the standard linear-quadratic model and the Alper-Howard-Flanders model are used. According to our calculations for a carbon ion spread-out Bragg peak at clinically relevant intermediate oxygen levels (0.5-20 mmHg), the advantage of carbon ions might be relatively moderate, with OER values about 1%-15% smaller than for protons. Furthermore, the variations of OER with LET are much smaller in vivo than in vitro due to different oxygen partial pressures used in cell experiments or measured inside tumours. The proposed OER model is a simple tool to quantify the oxygen effect in a practical way and provides the possibility to do hypoxia-based biological optimization in treatment planning. 相似文献
57.
Fiedler T Büning C Reuter W Pitre G Gentz E Schmidt HH Büttner J Ockenga J Gerloff T Meisel C Lochs H Roots I Köpke K Johne A 《European journal of clinical pharmacology》2007,63(10):917-925
Background The role of the single nucleotide polymorphisms (SNPs) on positions 2677G>T/A and 3435C>T of the multi-drug-resistance gene
1 (MDR1) in inflammatory bowel disease (IBD) remains unclear.
Aims To further elucidate the potential impact of MDR1 two-locus genotypes on susceptibility to IBD and disease behaviour.
Patients and methods Three hundred eighty-eight German IBD patients [244 with Crohn’s disease (CD), 144 with ulcerative colitis (UC)] and 1,005
German healthy controls were genotyped for the two MDR1 SNPs on positions 2677G>T/A and 3435C>T. Genotype–phenotype analysis was performed with respect to disease susceptibility
stratified by age at diagnosis as well as disease localisation and behaviour.
Results Genotype distribution did not differ between all UC or CD patients and controls. Between UC and CD patients, however, we observed
a trend of different distribution of the combined genotypes derived from SNPs 2677 and 3435 (χ2 = 15.997, df = 8, p = 0.054). In subgroup analysis, genotype frequencies between UC patients with early onset of disease and controls showed
significant difference for combined positions 2677 and 3435 (χ2 = 16.054, df = 8, p = 0.034 for age at diagnosis ≥25, lower quartile). Herein the rare genotype 2677GG/3435TT was more frequently observed (odds
ratio = 7.0, 95% confidence interval 2.5 – 19.7). In this group severe course of disease behaviour depended on the combined
MDR1 SNPs (χ2 = 16.101, df = 6, p = 0.017 for age at diagnosis ≥25). No association of MDR1 genotypes with disease subgroups in CD was observed.
Conclusions While overall genotype distribution did not differ, combined MDR1 genotypes derived from positions 2677 and 3435 are possibly associated with young age onset of UC and severe course of disease
in this patient group. 相似文献
58.
Neil R Price Amanda Charlton Itayi Simango Grahame HH Smith 《Journal of paediatrics and child health》2014,50(10):E102-E105
Aim: To explore the issue of appropriate management of testicular microlithiasis. We report the third ever case of tumour arising from a testis previously known to have microlithiasis in childhood and review the literature to provide an evidence‐based approach to management of testicular microlithiasis. Methods: Case report and review of previous literature. Results and Conclusions: Although there is a strong association between testicular microlithiasis and testicular malignancy at diagnosis, there are only three reported cases of subsequent tumour development in childhood. Testicular microlithiasis is an increasingly recognised entity. There is insufficient evidence in the current literature to support any regime of clinical surveillance. Self‐examination is the most important factor in the early detection of testicular malignancy. 相似文献
59.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
60.
J M Morgan M Wenzl W Lang G Lindinger L Deecke 《Electroencephalography and clinical neurophysiology》1992,83(6):378-388
This study was designed to investigate the predictive value of the event-related potentials (ERPs) preceding the initiation of a difficult perceptual-memory task and to investigate whether these ERPs require a motor movement on the part of the subject for their occurrence. Across 4 conditions the DC-potential shifts were recorded from 23 right-handed subjects using DC amplifiers. Although the start of each trial began with a ready signal, the conditions differed in that the subjects initiated the task by a button press in 2 conditions and the computer initiated it in 2 others without a press. The results showed that, especially in the frontocentral electrode sites, the DC-potential shifts which began those trials ending in correct performance were more negative relative to those trials ending in an incorrect response. Those conditions which required the subjects to self-initiate the trial and those which were initiated by the computer showed similar results indicating that the negative DC-potential shifts preceding correct performance are neither produced by nor depend on a task initiating motor movement. The onset of the DC-potential shifts preceded task initiation by up to 4.1 sec indicating that they were more than the Bereitschaftspotential. 相似文献