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41.
Frishberg Y Rinat C Shalata A Khatib I Feinstein S Becker-Cohen R Weismann I Wanders RJ Rumsby G Roels F Mandel H 《American journal of nephrology》2005,25(3):269-275
BACKGROUND/AIMS: Primary hyperoxaluria type 1 (PH1) is caused by the deficiency of the liver enzyme alanine:glyoxylate aminotransferase which results in increased synthesis and excretion of oxalate. The clinical manifestations of PH1 are heterogeneous with respect to the age of onset and rate of progression. The aim of this study was to investigate possible relationships between a given genotype, the biochemical profile and the clinical phenotype. METHODS: We conducted a study of 56 patients from 22 families with PH1 from Israel. The clinical and biochemical data were compiled and the genotype was determined for each family. RESULTS: The prevalent phenotype was of early onset with progression to end-stage renal disease during the first decade of life. Fifteen PH1-causing mutations were detected in 21 families: 10 were first described in this patient population. Marked intra-familial clinical heterogeneity was noted, meaning that there was no correlation between a given genotype and the phenotype. CONCLUSIONS: The clinical course of patients with PH1 is not dictated primarily by its genotype. Other genetic and/or environmental factors play a role in determining the ultimate phenotype. 相似文献
42.
The amygdala is known to regulate neuroendocrine and behavioral responses to a variety of stimuli. Herpes simplex virus-1 (HSV-1) is the common cause of viral encephalitis, manifested by hypothalamic-pituitary-adrenal (HPA) axis activation, fever, hypermotor activity and aggression. We examined here the role of the central amygdala (cAMG) in regulating the HPA axis function, febrile and behavioral responses to HSV-1 infection in rats. Bilateral electrolytic lesions were performed in the cAMG. HSV-1 encephalitis was induced by intracerebroventricular (ICV) inoculation of purified virions. Motor activity and body temperature were examined by a biotelemetric system. ICV inoculation of HSV-1 caused a marked time-dependent increase in serum corticotropin (ACTH) and corticosterone at 4 and 24 h post-infection. These responses were attenuated in rats with bilateral lesions of the cAMG. HSV-1 infection induced fever, motor hyperactivity and aggressive behavior. These responses were also attenuated in rats with cAMG lesions. The cAMG plays an important role in mediating the neuroendocrine, febrile and behavioral responses to HSV-1 infection. 相似文献
43.
Davidovits M Eisenstein B Ziv N Krause I Cleper R Bar-Sever Z 《Clinical nuclear medicine》2004,29(2):99-102
OBJECTIVE: The objective of this study was to estimate kidney length and function in patients with unilateral duplex kidney. MATERIALS AND METHODS: Thirteen patients with a unilateral duplicated system were reviewed retrospectively. The length of the kidneys was measured by ultrasound, and the relative function of the kidneys was estimated by renal scan. RESULTS: In all patients, the duplex kidney was the left one. The length of the right kidney on the renal ultrasound growth chart was from -1.5 to +0.4 standard deviations from the mean for age, and the left kidney length was from -0.5 to +4.3 standard deviations from the mean. On renal scans the kidneys with a duplicated system contributed 51 to 67% to total renal function; the contralateral ones, 33 to 49%. CONCLUSIONS: Kidneys with a duplicated system may be larger than their counterparts and they may contribute more to total renal function. When a disparity in length between the 2 kidneys is encountered, 1 of the possibilities that should be taken into account is a unilateral duplicated system. 相似文献
44.
Axer-Siegel R Ehrlich R Weinberger D Rosenblatt I Shani L Yassur Y Priel E Kramer M 《American journal of ophthalmology》2004,138(4):602-607
PURPOSE: To evaluate the visual outcome of patients with myopic subfoveal choroidal neovascularization (CNV) given photodynamic therapy (PDT) in a clinical setting, and to identify potential relation between the visual outcome and the age at treatment. DESIGN: Interventional case series. METHODS: Retrospective comparative study. SETTING: Outpatient ophthalmology clinic. PATIENTS: Twenty-nine consecutive patients (30 eyes) with subfoveal CNV caused by pathologic myopia who were treated with verteporfin PDT from January 2000 to May 2003. INTERVENTION: All the patients received verteporfin PDT and were followed clinically and with fluorescein angiography (FA). Review of the medical records and angiograms was performed. Patients were divided into two groups by age, using the median age (60 years) as the cutoff. MAIN OUTCOME MEASURES: Visual acuity (VA) at the end of follow-up in the older-patient group compared with the younger-patient group. RESULTS: The mean age was 63.1 years. Mean follow-up was 11.5 months. Patients received a mean of 3.48 treatments. Mean VA improved in the younger group from 0.63 to 0.39 logMAR (P = .02, paired t test) and deteriorated in the older group from 0.71 to 0.99 logMAR (P = .03, paired t test). In the whole cohort, 33% of eyes lost 3 or more lines of Snellen best-corrected VA; in the older age group, 50% of eyes lost 3 or more lines, whereas in the younger age group, only 8% of eyes did so (P = .024, Fisher's exact test). CONCLUSIONS: In our consecutive case series, visual prognosis of myopic CNV after PDT was found to be influenced by age at treatment. 相似文献
45.
46.
A new chromosome banding technique,spectral color banding (SCAN), for full characterization of chromosomal abnormalities 总被引:5,自引:0,他引:5
We have developed spectral color banding (SCAN) as a new chromosome banding technique based on spectral analysis of differentially labeled chromosome band-specific painting probes. In this study, we succeeded in displaying a multicolor banding pattern for chromosome 3, which was almost identical to the pattern obtained with the corresponding G-banding. We applied this method to metaphase cells from different normal male donors with various levels of G-banding resolution, ranging from 250 to 850 bands per haploid set. The same multicolor banding pattern was observed in all samples regardless of the length of the chromosomes or the quality of the G-banding. We then used SCAN in a diffuse large B-cell lymphoma case for a complete analysis of the intrachromosomal change for chromosome 3, which could not be fully characterized by G-banding or even by spectral karyotyping (SKY). SCAN could detect the duplicated segment and identify the origin of the chromosome band on the basis of the specific spectral color of each band. This study demonstrates that SCAN is a useful tool for full characterization of chromosomal abnormalities not identified by SKY. 相似文献
47.
Local injury to the endometrium doubles the incidence of successful pregnancies in patients undergoing in vitro fertilization 总被引:8,自引:0,他引:8
Barash A Dekel N Fieldust S Segal I Schechtman E Granot I 《Fertility and sterility》2003,79(6):1317-1322
OBJECTIVE: Exploration of the possibility that local injury of the endometrium increases the incidence of implantation. DESIGN: Prospective study. SETTING: Clinical IVF unit. PATIENT(S): A group of 134 patients, defined as good responders to hormonal stimulation, who failed to conceive during one or more cycles of IVF and embryo transfer (ET). INTERVENTION(S): The IVF treatment and ET were preceded by repeated endometrial biopsies, in a randomly selected 45 of a total of 134 patients. MAIN OUTCOME MEASURES: Outcome of IVF-ET treatments. RESULT(S): Transfer of a similar number of embryos (3.4 +/- 1.0 and 3.1 +/- 0.9 in the experimental and control patients, respectively) resulted in rates of implantation (27.7% vs. 14.2%, P =.00011), clinical pregnancy (66.7% vs. 30.3%, P =.00009), and live births per ET (48.9% vs. 22.5%, P =.016) that were more than twofold higher in the experimental group as compared to controls. CONCLUSION(S): These results suggest that IVF treatment that is preceded by endometrial biopsy doubles the chance for a take-home baby. 相似文献
48.
OBJECTIVE: To determine the potential efficacy of two simple fertility awareness-based methods of family planning-the Standard Days Method and the TwoDay Method-among breastfeeding women. DESIGN: Analysis of pre-existing data set, collected in 1986-1990. SETTING: Pre-existing data from Australia, Britain, and Canada. PATIENT(S): Seventy-three breastfeeding women in Australia, Britain, and Canada, who were followed starting 42 days postpartum, until they had at least two potentially fertile cycles (defined as cycles with adequate levels of urinary estrogens (E) and pregnanediol glucuronide and a long enough luteal phase to support a pregnancy). We examine this existing data set. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Probability of pregnancy from intercourse on different days of the cycle relative to ovulation for breastfeeding women following the instructions of the Standard Days Method or the TwoDay Method. RESULT(S): These two methods may be appropriate for different groups of breastfeeding women at different times. The Standard Days Method may be appropriate after cycle regularity is established, whereas the TwoDay Method may be a more effective option earlier in the postpartum period. CONCLUSION: A need remains for a more appropriate simple fertility awareness-based method during this early period. 相似文献
49.
Marek's disease virus is an oncogenic herpes virus of poultry that is highly cell associated. In the infected tissues and tumors the virus replicates in a low copy number. The propagation and dissemination of the virus takes place at the feather follicle epithelium, where the viral genome is produced in high copy number. As the viral genome is a large circular DNA molecule (200 kbp), pulsed field gel electrophoresis was used for separation of the viral genome directly from the infected chicken. DNA was extracted from tumors or feather tips by the phenol:chloroform technique or by low melting agar technique. It was found that feathers, being the site of virus productive replication, are useful for separation of free Marek's disease virus DNA from in vivo infections. 相似文献
50.
Segal E Dvorkin L Lavy A Rozen GS Yaniv I Raz B Tamir A Ish-Shalom S 《Journal of the American College of Nutrition》2003,22(3):201-207
BACKGROUND: Lactose intolerance (LI) is a common enzymatic insufficiency, manifesting by poor tolerance of dairy products, leading to low calcium intake and poor calcium absorption from dairy products. These changes might lead to an impairment of bone metabolism [1]. OBJECTIVES: To evaluate the impact of LI on quantitative bone parameters in axial and appendicular skeletal sites. To assess the impact of calcium intake from dairy and non-dairy nutritional sources, calcium regulating hormones and bone turnover on quantitative bone parameters in LI patients. METHODS: We evaluated calcium intake and bone status in sixty-six patients with LI, 49 women and 17 men, aged 20 to 78. Bone mass was assessed at the lumbar spine (LS), total hip (TH) and femoral neck (FN) by dual-energy x-ray absorptiometry (DEXA) and at the radius, tibia, phalanx by quantitative ultrasound. Serum calcium, albumin, inorganic phosphate, calcium regulating hormones and markers of bone turnover were evaluated. RESULTS: Total daily calcium intake was below the recommended by the American Dietetic Association [2] in all study participants (mean 692 mg/day +/- 162). Elevated level of urinary deoxypyridinoline crosslinks (DPD) was observed in 63 (96%) patients and was negatively correlated with total daily calcium intake (r = -0.998, p = 0.025) and with nondairy calcium intake (r = -0.34, p = 0.015). Parathyroid hormone (PTH) level in the upper third of normal range (45-65 ng/L) was observed in 11 (17%) patients. Parathyroid hormone (PTH) was inversely correlated with total calcium intake (r = -0.4, p = 0.001), dairy calcium intake (r = -0.83, p = 0.05), non-dairy calcium intake (r = -0.29, p = 0.043), 25OHD(3) serum level (r = -0.3, p = 0.007) and positively correlated with bone turnover markers (deoxypyridinoline crosslinks [DPD], r = 0.36, p = 0.01 and bone specific alkaline phosphatase [BSAP] r = 0.36, p = 0.01). Decrease in quantitative bone parameters compared to age-matched controls was observed in the axial and in the appendicular skeleton in men and in postmenopausal women: mean z-score for LS -0.87 +/- 0.22 and -1.32 +/- 0.65, p = 0.004 and 0.015, tibia -1.15 +/- 0.53 and -0.44 +/- 0.044, p < 0.001 and 0.27, phalanx -0.98 +/- 0.22 and -0.52 +/- 0.98, p < 0.001. We observed decrease in bone mass in patients with serum PTH in the upper tertile of normal range in the FN (z-score -0.57 +/- 0.6 versus -0.03 +/- 0.9, p = 0.025), TH (-0.51 +/- 0.96 versus 0.04 +/- 0.9, p = 0.05) and radius (-1.84 +/- 0.27 versus -0.07 +/- 1.61, p = 0.025, respectively). z-scores in FN and TH positively correlated with serum 25OHD(3) level (r = 0.31, 0.29; p = 0.014, 0.019). In postmenopausal women serum 25OHD(3) level correlated also with LS z-scores (r = 0.52, p = 0.004); FN and TH z-scores negatively correlated with DPD level (r = -0.51, p = 0.02 and r = -0.55, p = 0.04). CONCLUSION: LI state may lead to increased bone turnover and decreased bone mass especially in men and postmenopausal women. Impaired vitamin D status and low calcium intake may be deleterious to bone in this condition. 相似文献