全文获取类型
收费全文 | 12501篇 |
免费 | 895篇 |
国内免费 | 130篇 |
专业分类
耳鼻咽喉 | 192篇 |
儿科学 | 201篇 |
妇产科学 | 265篇 |
基础医学 | 1768篇 |
口腔科学 | 308篇 |
临床医学 | 1132篇 |
内科学 | 2337篇 |
皮肤病学 | 599篇 |
神经病学 | 719篇 |
特种医学 | 990篇 |
外科学 | 1914篇 |
综合类 | 68篇 |
一般理论 | 1篇 |
预防医学 | 879篇 |
眼科学 | 192篇 |
药学 | 958篇 |
中国医学 | 156篇 |
肿瘤学 | 847篇 |
出版年
2023年 | 84篇 |
2022年 | 184篇 |
2021年 | 362篇 |
2020年 | 216篇 |
2019年 | 293篇 |
2018年 | 346篇 |
2017年 | 245篇 |
2016年 | 390篇 |
2015年 | 536篇 |
2014年 | 678篇 |
2013年 | 793篇 |
2012年 | 1008篇 |
2011年 | 997篇 |
2010年 | 647篇 |
2009年 | 533篇 |
2008年 | 700篇 |
2007年 | 674篇 |
2006年 | 600篇 |
2005年 | 590篇 |
2004年 | 460篇 |
2003年 | 383篇 |
2002年 | 343篇 |
2001年 | 238篇 |
2000年 | 246篇 |
1999年 | 205篇 |
1998年 | 131篇 |
1997年 | 135篇 |
1996年 | 123篇 |
1995年 | 90篇 |
1994年 | 92篇 |
1993年 | 78篇 |
1992年 | 73篇 |
1991年 | 64篇 |
1990年 | 81篇 |
1989年 | 79篇 |
1988年 | 76篇 |
1987年 | 71篇 |
1986年 | 76篇 |
1985年 | 77篇 |
1984年 | 51篇 |
1983年 | 61篇 |
1982年 | 38篇 |
1981年 | 46篇 |
1980年 | 32篇 |
1979年 | 36篇 |
1978年 | 32篇 |
1977年 | 35篇 |
1976年 | 33篇 |
1975年 | 25篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
91.
Scanning electron microscopy demonstrates that crystalline silica destroys liver Kupffer cells but has no other obvious deleterious effects on the liver. Silica-treated livers still retain the ability to trap large numbers of bacteria perfused through the portal vein even though the rate of clearance is well below normal. In vivo, silica treatment decreases the rate of bacterial clearance from the blood, alters the in vivo organ distribution of cleared bacteria, and decreases the mean lethal dose of Salmonella typhimurium over 100-fold. Cumulatively, the data indicate that silica treatment enhances susceptibility to gram-negative infection, probably by destruction of macrophages. 相似文献
92.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
93.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
94.
S. C. Kim Y. T. Moon Y. P. Hong T. K. Hwang S. H. Choi K. J. Kim C. K. Sul T. C. Park Y. G. Kim K. S. Park 《Journal of Korean medical science》1998,13(2):138-146
To estimate the prevalence of urinary stone disease in Koreans, and to determine the inter-relationships between urinary stone disease and various epidemiological factors, 1,521 controls and 1,177 cases with urinary stones were evaluated. Of special interest in this study were: 1) proportion of past urinary stone history among controls; 1.9% 2) the point prevalence rate of urinary stones among controls; 0.2% 3) the recurrence rate of urinary stones (the proportion of past history of urinary stone) among cases; 56.8% 4) high incidences (76.3%) in the thirties to the fifties among cases 5) the risk factors for urolithogenesis; obesity [higher than 25 of BMI (body mass index, weight/height2)], more than 10 year-experience as a production worker, past stone history, familial stone history, low physical activity (< 2,000 Kcal/day), and low intake of fruit. However, the well-known risk factors for urinary stones; over intake of meat or fish and milk or dairy products, perspiration, amount and kind of drinking water, and stress unexpectedly were not significantly different between the controls and the cases. 相似文献
95.
Vaccination of pregnant dams with intimin(O157) protects suckling piglets from Escherichia coli O157:H7 infection 总被引:3,自引:0,他引:3
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dean-Nystrom EA Gansheroff LJ Mills M Moon HW O'Brien AD 《Infection and immunity》2002,70(5):2414-2418
Cattle are important reservoirs of enterohemorrhagic Escherichia coli (EHEC) O157:H7 that cause disease in humans. Both dairy and beef cattle are asymptomatically and sporadically infected with EHEC. Our long-term goal is to develop an effective vaccine to prevent cattle from becoming infected and transmitting EHEC O157:H7 to humans. We used passive immunization of neonatal piglets (as a surrogate model) to determine if antibodies against EHEC O157 adhesin (intimin(O157)) inhibit EHEC colonization. Pregnant swine (dams) with serum anti-intimin titers of < or =100 were vaccinated twice with purified intimin(O157) or sham-vaccinated with sterile buffer. Intimin(O157)-specific antibody titers in colostrum and serum of dams were increased after parenteral vaccination with intimin(O157). Neonatal piglets were allowed to suckle vaccinated or sham-vaccinated dams for up to 8 h before they were inoculated with 10(6) CFU of a Shiga toxin-negative (for humane reasons) strain of EHEC O157:H7. Piglets were necropsied at 2 to 10 days after inoculation, and intestinal samples were collected for determination of bacteriological counts and histopathological analysis. Piglets that ingested colostrum containing intimin(O157)-specific antibodies from vaccinated dams, but not those nursing sham-vaccinated dams, were protected from EHEC O157:H7 colonization and intestinal damage. These results establish intimin(O157) as a viable candidate for an EHEC O157:H7 antitransmission vaccine. 相似文献
96.
Esophageal ulceration triggers expression of hypoxia-inducible factor-1 alpha and activates vascular endothelial growth factor gene: implications for angiogenesis and ulcer healing
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Baatar D Jones MK Tsugawa K Pai R Moon WS Koh GY Kim I Kitano S Tarnawski AS 《The American journal of pathology》2002,161(4):1449-1457
97.
Bong Hyo Lee Rong Jie Zhao Jin Young Moon Seong Shoon Yoon Jung-Ae Kim Heeduk An Young Kyu Kwon Meeyul Hwang Seong Hun Choi Insop Shim Bong Hyun Kim Chae Ha Yang 《Neuroscience letters》2008
In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats. 相似文献
98.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
99.
This study was designed to determine whether the somatostatin analogue,
octreotide, could prevent embryonic loss by normalizing increased uterine
insulin-like growth factor-I (IGF-I) action related to hyperoestrogenaemia
following superovulation. Superovulated immature and
oestradiol-17beta-treated adult rats were infused with 100 or 300 microg/ml
of octreotide respectively, or injected daily with 1 or 10 microg of
octreotide from day 1 to day 3 of pregnancy. On day 3, embryos were
collected from the oviducts and uteri. Uterine luminal fluid was subjected
to embryo culture. The amounts of uterine IGF-I and IGF binding proteins
(IGFBP) were determined by radioimmunoassay and ligand binding assay
respectively. Octreotide infusion normalized uterine IGF-I action following
superovulatory and oestradiol-17beta treatment, by reducing IGF-I
concentrations and increasing IGFBP concentrations. Octreotide infusion
increased the number of normal embryos by 2.7-fold and 1.7-fold in
superovulated and oestradiol-17beta- treated rats respectively, and
reversed the detrimental effects of uterine luminal fluid on embryonic
development caused by superovulatory and oestradiol-17beta treatment. Daily
injections with octreotide had similar but reduced effects in all
parameters examined in both treatment groups. In conclusion, octreotide may
reduce embryonic loss, at least in part, by normalizing IGF-I action
following superovulation.
相似文献
100.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4