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991.
Two autologous and 4 allogeneic conjunctival grafts have been transplanted to the corneal-scleral region in 6 dogs. The animals with the autografts and 2 of the allografts were untreated, while the animals with the other 2 allografts were treated with azathioprine and prednisolone. The grafts were followed with daily sequential, still photographic recording of the spreading of the fluorescence over the graft surfaces after fluorescein sodium had been given intravenously. A motordriven camera, with automatically timed exposures at very short intervals down to 1 sec, was used in combination with a fast recycling flash unit. The behaviour of the circulation seemed to be the same in auto- and in allografts during the first 8 days of healing. One day before showing signs of rejection at oridinary inspection, the two untreated allografts, on photographic analysis of the spreading of fluorescence, showed minute areas of non-fluorescence in an early stage of the procedure. The same type of local impairment of the circulation, manifested by slower uptake of dye in limited areas, was noted in the treated allografts, appearing 2-3 days before severe signs of rejection were noted at orinary inspection. These areas, however, gradually filled with dye during the further course of the test, to such a degree that the irregularities in the spreading of the fluorescence might easily have been overlooked in an oridinary fluorescein test. The disturbance of the circulation gradually increased during the course of the rejection and, at the stage when changes were observed at ordinary inspection, the circulation was severely impaired, as indicated by a complete non-appearance of fluorescence in certain areas, or in the whole graft. It is suggested that the modification of the classic fluorescein test described here, in detecting the early circulatory irregularities, indicates more precisely the start of the rejection process than do the criteria of allograft rejection used so far, and that it is, therefore, a sensitive means of evaluating the effects of various immunosuppressive procedures.  相似文献   
992.
Straight line sign: appearance and significance during CT portography   总被引:4,自引:0,他引:4  
Tyrrel  RT; Kaufman  SL; Bernardino  ME 《Radiology》1989,173(3):635-637
The computed tomographic (CT) angiograms of 44 patients who were being evaluated for possible hepatic surgery were studied. All patients were imaged with CT arterial portography (CTAP), delayed CT of the liver, and magnetic resonance (MR) imaging. All CTAP studies were evaluated for a "straight line," a linear variation in contrast within the liver. Sixteen patients (36%) demonstrated the straight line sign. All 16 had a mass at the proximal portion of the defect. Nine of 16 had defects that clearly correlated with portal venous distribution seen at limited digital angiography. Fourteen of the 16 patients showed loss of the straight line sign at delayed CT and/or MR imaging of the liver. These defects are thought to be due to vascular obstruction. The straight line sign will probably be seen more frequently as CTAP is more commonly used. Recognition of the sign is important in the evaluation of primary liver carcinomas, since it signifies that the tumor may be inoperable. Also, if metastatic disease is present, it alerts the surgeon to the proximity of the portal vein to the neoplasm.  相似文献   
993.
To describe the inter-relationship of chronic illness severity as perceived by adolescents with both psychosocial well-being and objective measures of illness severity. Additionally to compare the adolescents' perception of illness severity with how their physicians believe that the adolescents perceive their illness severity.

Methods:


The psychological well-being of 48 adolescents with either cystic fibrosis (CF) or insulin-dependent diabetes mellitus (IDDM) was measured by four standardized questionnaires. The adolescents' perception of severity of illness was measured using an original instrument (PSCI), and this measure was compared to their physicians' estimates of how the adolescents perceived the severity of their illness and clinical illness.

Results:


There were 24 patients in both the CF and IDDM groups. Both groups were found to function well psychosocially; although, there were more patients with low self image compared to normative values. Depression and low self image were associated with a greater adolescent perception of illness severity. For both chronic illness groups, physicians' assessment of assumed adolescent perception of disease severity correlated with clinical indices of disease severity and was higher than the perception of illness severity reported by the adolescents. For adolescents with CF, but not with IDDM, perception of severity of chronic illness correlated with clinical indices.

Conclusions:


For adolescents with chronic illness, their perception of illness severity is an important indicator of psychosocial well-being. Physicians do not accurately infer their patients' perception of illness severity.  相似文献   
994.
The aim of the present study was to investigate enzyme levels of the malate-aspartate and alpha-glycerophosphate shuttles in type I (slow-twitch) and type II (fast-twitch) fibres of human skeletal muscle. The influence of endurance training on these levels was also elucidated. Biopsy specimens were obtained from the lateral part of the quadriceps femoris muscle of six untrained and six endurance-trained subjects. Type I vs. type II. In both groups the type I fibres exhibited higher levels of the TCA cycle marker enzyme citrate synthase (CS), as well as of the malate-aspartate shuttle enzymes (cytoplasmic and mitochondrial malate dehydrogenase (cMDH, mMDH), and aspartate aminotransferase (cASAT, mASAT]. A more pronounced difference between type I and type II fibres was noted for cMDH (58%) than for mMDH (16%), cASAT (20%), mASAT (18%) and CS (25%). In contrast to these enzymes, the levels of cytoplasmic glycerol-3-phosphate dehydrogenase (cGPDH), the enzyme representative of the alpha-glycerophosphate shuttle, were higher (25%) in the type II fibres. Endurance-trained vs. untrained. In the endurance-trained group, both fibre types were characterized by higher levels of CS (mean for both fibre types: 48%) as well as of mitochondrial malate-aspartate shuttle enzymes (mMDH: 47%, mASAT: 48%) than in the corresponding fibre types in the untrained group, while the differences in the levels of cytoplasmic malate-aspartate shuttle enzymes (cMDH: 13%, cASAT: 16%) were not statistically significant. Nor were the differences in cGPDH levels (8%) between the untrained and endurance-trained groups statistically significant. It is concluded that in human skeletal muscle, malate-aspartate shuttle enzymes are expressed to a higher degree in type I (slow) fibres than in type II (fast) fibres, with cMDH exhibiting the most marked difference. The single fibre analysis indicated that the muscle's activity level might exert a greater influence on the mitochondrial isoenzymes than on the cytoplasmic ones. In contrast to the malate-aspartate shuttle enzymes, the alpha-glycerophosphate shuttle is expressed to a higher degree in type II fibres and its capacity appears to not be influenced by endurance training. The present studies demanded considerable methodological investigations which also are presented in this paper.  相似文献   
995.
The aim of this study was to determine basal serum vascular endothelial growth factor (VEGF) concentrations and Doppler blood flow changes within the ovarian stroma of women with polycystic ovaries (PCO) and women with normal ovaries. Pulsed and colour Doppler blood flows within the ovarian stroma were recorded, and serum VEGF concentrations measured, in the early follicular phase (days 2-3 of a menstrual cycle) in 60 women undergoing ovarian stimulation for in-vitro fertilization. 36 women had normal ovaries, 14 women had PCO as seen on pelvic ultrasound examination and 10 had polycystic ovarian syndrome (PCOS). Mean+/-SD serum VEGF concentrations were significantly higher (P < 0.001) in women with PCO and PCOS (3.4+/-0.7 and 3.2+/-0.66 ng/ml respectively) compared with women with normal ovaries (2.3+/-0.5 ng/ml). Mean peak systolic blood flow velocity (PSV) and time-averaged maximum flow velocity (TAMXV) were significantly higher (P < 0.001) in women with PCO and PCOS compared with women with normal ovaries. The mean PSV were 15+/-4 and 16+/-4 cm/s in women with PCO and PCOS respectively, compared with 9+/-2 cm/s in women with normal ovaries. The TAMXV were 9+/-3 and 11+/-3 cm/s in women with PCO and PCOS respectively compared with women with normal ovaries (5.8+/-1.5 cm/s). Serum VEGF concentrations were positively correlated with PSV (r=0.44, P=0.001) and TAMXV (r=0.45, P < 0.000) in all three groups of women. Higher serum concentrations of VEGF in women with PCO and PCOS may relate to the increased vascularity that underlies the increased blood flow demonstrated by Doppler blood flow velocity measurements in these women. The results may explain the higher risk of ovarian hyperstimulation syndrome in programmes of ovarian stimulation in patients with PCO compared with those with normal ovaries.   相似文献   
996.
To examine the influence of sample cellularity and the presence of endocervical columnar cells on the detection of cervical dysplasia, Papanicolaou (Pap) smears taken from patients with biopsy-proven CIN II and III were analyzed retrospectively. Adequacy was semiquantitated by dividing each smear into 15 equal areas using a lined template and assigning an adequacy index (AI) of 0 to 15. The total false-negative (FN) rate was 15.8 percent, with 6.1% representing interpretive error and 9.7% representing sampling error. For FN slides truly lacking abnormal cells, the average AI was significantly lower than that of true positives (TP), even when endocervical columnar cells were present. The entire group was then blindly re-evaluated using a subjective application of the Bethesda System, classifying slides as satisfactory, less than optimal, and unsatisfactory. Although correlation of AI with the rapid Bethesda System categorization was imperfect, the exclusion of less than optimal and unsatisfactory smears also lowered the FN rate, but less effectively. An AI scoring technique, therefore, may be useful in the routine evaluation of Pap smear adequacy.  相似文献   
997.
We have established a probe order within the Angelman/Prader–Willichromosomal regions by multicolor fluorescence in situ hybridization(FISH). The probe [locus] order extending distally from thecentromere is 34[D15S9]-IR4–3R[D15S11]-189–1[D15S13]-PW71[D15S63] -3–21[D15S10] -28ß3-H3[GABRB3] -IR10–1[D15S12]. This order agrees with that recently reported (1)with the exception of PW71 [D15S63]. In addition, a second  相似文献   
998.
根据天花粉蛋白(Tk)作用了淋巴细胞体外增殖的抑制是否由CD8细胞所介导,健康人群被分成介导型(M~+)和非介导型(M~-)两类。我们已有的工作证明,性状M~+/M~-由HLA连锁的一对孟德尔基因控制。本文采用分子生物学手段,对M~+”和M~-个体作HLAⅡ类基因的精细分型,发现编码DQ异二聚体分子的DQA和DQB两个基因同时决定M~+的表达,而且等位基因DQA1*0501和DQB1*0201以顺式和反式两种形式发挥互补作用,从而把人体中调控Tk免疫应答的遗传成份直接定位在该特定DQ分子的编码基因上。这一互补现象同时解释了DR3、DR5和DR7与M~+呈现次级关联的复杂格局。  相似文献   
999.
Epidemiological and laboratory studies indicate that polychlorinated biphenyls (PCBs) and methyl mercury (MeHg) may have additive or interactive adverse effects on nervous system function. Prior studies have shown that high doses of MeHg target the cerebellum and impair balance and coordination, but the effects of PCBs on cerebellar function were unknown. In addition, the combined effects of PCBs and MeHg on cerebellar function have not been studied previously. Therefore, we investigated the effects of developmental exposure to PCBs, MeHg, or PCBs + MeHg on three motor tasks that involve cerebellar functions. Female Long-Evans rats were exposed to MeHg (0.5 ppm in drinking water), PCBs (6-mg/kg/d Aroclor 1254), PCBs + MeHg, or vehicle only beginning 4 weeks prior to breeding, through pregnancy, and continuing through postnatal day (PND) 16. Starting at approximately PND 60, one male and one female from each litter were tested on three motor tasks that involve cerebellar function. PCB + MeHg-exposed rats were impaired relative to the controls on a task requiring them to traverse a rotating rod. Rats exposed to PCBs alone were also somewhat impaired relative to the controls, whereas MeHg-exposed rats were not significantly different from the controls. There were no statistically significant deficits related to PCB or MeHg exposure on a vertical rope-climbing test or a parallel bar test. Our results demonstrate that the possibility of additive neurotoxic effects of PCBs and MeHg needs to be seriously considered.  相似文献   
1000.
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