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51.
52.
Eva Yacobi B.A. Colleen Tennant MSPH Jeanne Ferrante M.D. Naazneen Pal B.A. Richard Roetzheim M.D. MSPH 《Preventive medicine》1999,28(6):535-541
BACKGROUND: The purpose of this study was to evaluate the knowledge, attitudes, and behaviors of university students regarding the human papillomavirus (HPV). METHODS: A random sample of 500 university students was mailed a self-administered questionnaire that elicited their knowledge and awareness about HPV and compared their knowledge and attitudes with those of other sexually transmitted diseases (STDs). Among the 480 deliverable addresses, 289 students responded (response rate 60%). RESULTS: Only 37% of respondents had ever heard of HPV, and the median score on a 13-item knowledge scale was only 3. Of seven STDs assessed, respondents indicated they knew the least about HPV and perceived that this STD has received the least educational effort. In multivariate analyses, predictors of lower knowledge and awareness about HPV were male gender and sexual behavior (having multiple partners, not using condoms). CONCLUSIONS: Despite the high prevalence of HPV among young adults, most students knew very little about this infection. Implementing HPV educational programs and measuring their effectiveness should be a priority. 相似文献
53.
The qualitative and quantitative difference in the various ginsenoside constituents of the crude butanol-soluble saponin fractions of callus cultures of two Indian species of Panax namely P. sikkimensis and P. pseudoginseng have been compared with that of P. quinquefolium (American ginseng). The 45-50 days old calli of the two Indian species, though found to accumulate crude ginsenoside at levels (0.9% and 1.1%, respectively) comparable to that in P. quinquefolium (1.2%), P. pseudoginseng callus showed high productivity of ginsenosides Rf (40.57%) and Ro (19.60%). P. quinquefolium calli on the other hand accumulated more of Rb and Rg group of ginsenosides but while the former appeared to be a Rg (2) accumulator the callus of the later was rich in the Rg (1) fraction. 相似文献
54.
55.
Evaluation of oxygen saturation monitoring by pulse oximetry in neonates in the delivery system 总被引:1,自引:0,他引:1
Ivan Dimich Prithi Pal Singh Alvin Adell Michele Hendler Norman Sonnenklar Mennakshi Jhaveri 《Journal canadien d'anesthésie》1991,38(8):985-988
The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2). Measurements of SpO2 were taken at 1, 5, 10 min, and 24 hr after delivery. At one and five minutes, SpO2 recorded from the right hand was higher than that recorded from the lower extremities (71.9% +/- 6.5% vs 63.4% +/- 4.3% and 83.3% +/- 4.2% vs 76% +/- 4.1%, mean +/- SD, respectively). At ten minutes these differences diminished, and had almost completely disappeared after 24 hr. These results can be explained by the presence of R-L shunting at the ductus arteriosus level, producing reduced SaO2 in the lower extremities. Oxygen saturation did not differ between neonates delivered vaginally or by Caesarean section, regardless of the presence or type of anaesthesia. We concluded that neonates remain relatively desaturated in the immediate postpartum period and that the SpO2 obtained from the right hand is a better index of neonatal oxygenation than that obtained from the heel. 相似文献
56.
Laszlo Prokai Katalin Prokai-Tatrai Pal Perjesi Alevtina D Zharikova James W Simpkins 《Drug metabolism and disposition》2003,31(6):701-704
According to a recently reported metabolic pathway, phenolic A-ring estrogens are metabolized in rat liver microsomes partially to the corresponding quinols by cytochrome P450 isoenzymes. We found that these quinols could, in turn, undergo reduction to regenerate the parent estrogens consumed during the metabolic process. Among the tested endogenous reducing agents, NADH and especially NADPH produced a significant extent of reductive conversion. Enzymes available in rat liver microsomes further catalyzed this reaction with 6.5 +/- 1.5 nmol. min(-1). (mg of protein)(-1) measured as the initial rate of estrone formation at 37 degrees C, whereas the initial rate of second-order reaction for the reduction of E1-quinol by a 10-fold excess of NADPH in a microsome-free buffer solution and under identical incubation conditions was 0.62 +/- 0.03 nmol. min(-1). The quinol route is, therefore, unique among estrogen-metabolizing pathways for its bioreversibility due to the facile regeneration of the phenolic A-ring estrogens consumed in the preceding oxidative process. 相似文献
57.
Effects of long-term administration of androgens and estrogen on rhesus monkey prostate: possible induction of benign prostatic hyperplasia 总被引:6,自引:0,他引:6
Rhesus monkeys were used to investigate the role of androgenic steroids and estradiol in the induction of hyperplastic changes in stromal and glandular prostate tissues. Adult male rhesus monkeys were procured from the wild and, after routine quarantine procedures, were randomly divided into 5 groups of 5 animals each. Gluteus maximus muscles were injected with 2.5 mg of androstenedione (Group II), 2.5 mg of dihydrotestosterone (DHT) or 0.25 mg of estradiol (Group II), 2.5 mg androstanediol (Diol; Group IV), or Diol in combination with 0.25 mg of estradiol (Group V). Group I consisted of untreated controls. Animals were injected with steroids 3 times a week for 2 years. Treatment with androstenedione (Group II) resulted in stromal hyperplasia in the caudal lobe and an increase in epithelial cell height in all zones except in the central zone of the caudal lobe. In monkeys treated with DHT and estradiol (Group III), stromal hyperplasia in both lobes, a decrease in tubular size, and degranulation and vacuolation of epithelial cells were noticed. Injection of Diol alone (Group IV) or in combination with estradiol (Group V) resulted in a widening of stroma in the central and peripheral zones of cranial and caudal lobes, whereas the tubular size decreased. Diol also induced epithelial cell hypercellularity in the central and peripheral zones of the caudal lobe and in the peripheral zone of the cranial lobe. Prostate-specific antigen levels in Group IV animals gradually increased from 6 months of treatment and were maximal after 18 months of injections. Serum estradiol levels increased to detectable levels in all groups except Group IV. Serum testosterone levels decreased to very low or undetectable levels in all groups, whereas prostate-specific acid phosphatase increased in all treated groups. Prolactin levels were elevated in all treated groups except in animals injected with androstenedione. These results indicate that repeated long-term injections of androstenedione or DHT and estradiol induced stromal hyperplasia, which may be an estrogen-related effect. Androstanediol-induced hypercellularity and stratification of glandular epithelium is comparable to human prostatic intraepithelial neoplasia. These results also suggest that the rhesus monkey is a suitable animal model for experimental induction of prostate diseases. 相似文献
58.
Treatment for asymptomatic anthracycline-induced cardiac dysfunction in childhood cancer survivors: the need for evidence. 总被引:1,自引:0,他引:1
E C van Dalen H J H van der Pal C van den Bos H N Caron L C M Kremer 《Journal of clinical oncology》2003,21(17):3377; author reply 3377-3377; author reply 3378
59.
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation. 相似文献
60.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献