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1.
2.
This case describes a rare complication of prostaglandin analogue eye drops used for treatment of primary open angle glaucoma. Though increase in the number, size and pigmentation of eyelashes is well‐known, this case shows extensive hair growth in malar region, which can be unacceptable. This complication can be one of the causes of discontinuation of prostaglandin analogue therapy. 相似文献
3.
4.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
5.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
6.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
7.
Experiments were undertaken using an ovarian adenocarcinoma cell line (A2780) and a drug-resistant strain (A2780.ad) derived from this line. P-glycoprotein could not be detected in A2780 cells but was essentially ubiquitous in A2780.ad cells, although removing the selective pressure for drug resistance led to reduced expression. However, the amount of P-glycoprotein present was used to predict the capacity of these cells to extrude rhodamine-123 (R-123) and their resistance to adriamycin, a cytotoxic drug. This accords with the role of P-glycoprotein as a drug pump. Although hypotonic solutions increased anion efflux from A2780 and A2780.ad cells, larger responses occurred in the parental line. Moreover, R-123 extrusion and anion efflux appeared to be mutually independent processes and so these data do not support the view that P-glycoprotein is involved in the control of volume-sensitive anion channels. Hypotonic solutions increased intracellular free calcium ([Ca2+]i) in drug-resistant cells but not in the parental line, and so establishing a drug-resistant strain may affect the control of [Ca2+]i during osmotic swelling. This could account for effects that were previously attributed to P-glycoprotein. 相似文献
8.
Food intake and energy expenditure of cachectic tumour bearing mice were measured during the course of weight loss. Four weeks after implantation of the MAC-16 tumour the body weight was reduced by 20%, there was no significant reduction in food intake, and body composition analysis revealed that both body fat and protein mass were decreased. Oxygen consumption and carbon dioxide production were measured over a 24h period both before and at weekly intervals after tumour implantation. There was a gradual increase in the rates of both oxygen consumption and carbon dioxide production per gram body weight. Similarly, energy expenditure per gram body weight was increased during the 3rd (11%) and 4th (23%) weeks. In contrast, the food intake per gram body weight was unchanged during the first three weeks and increased by only 8% during the 4th week. Despite the development of cachexia, rates of protein synthesis in the liver, heart, kidney and skeletal muscle were the same four weeks after tumour implantation as those in non-tumour bearing mice. Thus, in this murine model of cancer cachexia a negative energy balance resulted from failure of food intake to compensate for increased energy demands. These findings point to the unique pattern of metabolic alterations which occur in different models of cancer cachexia. 相似文献
9.
Absorption/metabolism of sulforaphane and quercetin, and regulation of phase II enzymes, in human jejunum in vivo. 总被引:2,自引:0,他引:2
Niclas Petri Christer Tannergren Birgit Holst Fred A Mellon Yongping Bao Geoff W Plumb Jim Bacon Karen A O'Leary Paul A Kroon Lars Knutson Patrik Forsell Thomas Eriksson Hans Lennernas Gary Williamson 《Drug metabolism and disposition》2003,31(6):805-813
For the first time the human intestinal effective permeability, estimated from the luminal disappearance and intestinal metabolism of phytochemicals, sulforaphane and quercetin-3,4'-glucoside, as well as the simultaneous changes in gene expression in vivo in enterocytes, has been studied in the human jejunum in vivo (Loc-I-Gut). Both compounds as components of an onion and broccoli extract could readily permeate the enterocytes in the perfused jejunal segment. At the physiologically relevant, dietary concentration tested, the average effective jejunal permeability (Peff) and percentage absorbed (+/- S.D.) were 18.7 +/- 12.6 x 10-4 cm/s and 74 +/- 29% for sulforaphane and 8.9 +/- 7.1 x 10-4 cm/s and 60 +/- 31% for quercetin-3,4'-diglucoside, respectively. Furthermore, a proportion of each compound was conjugated and excreted back into the lumen as sulforaphane-glutathione and quercetin-3'-glucuronide. The capacity of the isolated segment to deconjugate quercetin from quercetin-3,4'-diglucoside during the perfusion was much higher than the beta-glucosidase activity of the preperfusion jejunal contents, indicating that the majority (79-100%) of the beta-glucosidase capacity derives from the enterocytes in situ. Simultaneously, we determined short-term changes in gene expression in exfoliated enterocytes, which showed 2.0 +/- 0.4-fold induction of glutathione transferase A1 (GSTA1) mRNA (p < 0.002) and 2.4 +/- 1.2-fold induction of UDP-glucuronosyl transferase 1A1 (UGT1A1) mRNA (p < 0.02). The changes in gene expression were also seen in differentiated Caco-2 cells, where sulforaphane was responsible for induction of GSTA1 and quercetin for induction of UGT1A1. These results show that food components have the potential to modify drug metabolism in the human enterocyte in vivo very rapidly. 相似文献
10.
Edward C. Ditkoff Jennifer Plumb Amy Selick Mark V. Sauer 《Journal of assisted reproduction and genetics》1997,14(3):145-147
Purpose: Our purpose was to characterize and describe anesthesia practice in programs performing IVF in the United States.
Methods: We used a telephone survey requiring respondents to be either the program director, a physician, or a nurse familiar with
the practice. Two hundred seven (78%) Society of Assisted Reproductive Technology (SART) registered programs agreed to participate.
Programs were divided by geographic region and type of practice (academic versus private).
Results: Ninety-one private (68%) and 41 academic (56%) programs used personnel provided by the Department of Anesthesiology. Conscious
sedation was performed most commonly (95%). The remaining 5% used primarily either general, regional, or local anesthesia.
Typical recovery times were 90 to 120 min. Average costs of anesthetic administration were $300–$400 and were similar among
groups except for the Eastern academic programs, with a higher mean cost of $543. Programs using personnel from anesthesiology
reported higher costs compared to programs utilizing their own staff ($391±15 vs $157±11; P<0.05). Complications were infrequent
(<10%); no hospitalizations or serious life-threatening incidents were reported.
Conclusions: A large number of programs safely used their own trained personnel to deliver anesthesia, and realized a significant reduction
in cost. 相似文献