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排序方式: 共有1725条查询结果,搜索用时 15 毫秒
71.
Ahmed S Sileno AP deMeireles JC Dua R Pimplaskar HK Xia WJ Marinaro J Langenback E Matos FJ Putcha L Romeo VD Behl CR 《Pharmaceutical research》2000,17(8):974-977
Purpose. The present study was conducted to evaluate theeffects of formulation pH and dose on nasal absorption of scopolaminehydrobromide, the single most effective drug available for the prevention ofnausea and vomiting induced by motion sickness.
Methods. Human subjects received scopolamine nasally at adose of 0.2 mg/0.05 mL or 0.4 mg/0.10 mL, blood samples were collected atdifferent time points, and plasma scopolamine concentrations were determinedby LC-MS/MS.
Results. Following administration of a 0.2 mg dose, theaverage Cmax values were found to be 262 ± 118, 419± 161, and 488 ± 331 pg/mL for pH 4.0, 7.0, and 9.0formulations, respectively. At the 0.4 mg dose the average Cmaxvalues were found to be 503 ± 199, 933 ± 449, and 1,308± 473 pg/mL for pH 4.0, 7.0, and 9.0 formulations, respectively. At a0.2 mg dose, the AUC values were found to be 23,208 ± 6,824, 29,145± 9,225, and 25,721 ± 5,294 pg.min/mL for formulation pH 4.0,7.0, and 9.0, respectively. At a 0.4 mg dose, the average AUC value wasfound to be high for pH 9.0 formulation (70,740 ± 29,381 pg.min/mL)as compared to those of pH 4.0 (59,573 ± 13,700 pg.min/mL) and pH 7.0(55,298 ± 17,305 pg.min/mL) formulations. Both the Cmaxand AUC values were almost doubled with doubling the dose. On the otherhand, the average Tmax values decreased linearly with a decreasein formulation pH at both doses. For example, at a 0.4 mg dose, the averageTmax values were 26.7 ± 5.8, 15.0 ± 10.0, and 8.8± 2.5 minutes at formulation pH 4.0, 7.0, and 9.0, respectively.
Conclusions. Nasal absorption of scopolamine hydrobromidein human subjects increased substantially with increases in formulation pHand dose. 相似文献
72.
Hosalkar HS Cheung-Moore E Atanda A Ogilvie C Lackman RD 《American journal of orthopedics (Belle Mead, N.J.)》2005,34(7):333-336
We present a rare case of a myxoid-feature lipoma that arose in the patella fat pad and caused patellar tendon rupture. 相似文献
73.
Many plants are known to possess antifertility activity. However, limited attempts have been made to scientifically evaluate these claims. Hibiscus rosa-sinensis flowers have been shown to possess antifertility and abortifacient activity. In this report, antiimplantation activity of water extract of leaves of H. rosa-sinensis was investigated. Pregnant female mice were dosed with extract (100 mg/kg body weight) from days 1 to 6 of pregnancy. No implantation sites were observed in treated animals when they were surgically opened on day 15 of pregnancy. Biochemical and biophysical alterations were observed in the endometrium in treated animals, especially on day 5, at 4:40 a.m., the day of implantation. A sharp increase in superoxide anion radical and a sharp fall in superoxide dismutase (SOD) activity, as seen in the endometrium from control animals, were altered in treated animals. The extract also exhibited antiestrogenic activity, as judged by increase in uterine weight. The physiological alterations induced by water extract of H. rosa-sinensis are discussed. 相似文献
74.
75.
Worawittayawong P Leigh CM Cozens G Peirce EJ Setchell BP Sretarugsa P Dharmarajan A Breed WG 《International journal of andrology》2005,28(3):180-188
In the greater bandicoot rat, Bandicota indica, of south-east Asia, nine cell associations were documented in the testicular seminiferous epithelium. In about 10% of the tubule cross sections two or more cell associations occurred and, furthermore, some of the generations of germ cells within the cell associations were sometimes either out of phase, or missing, in the tubule cross sections. These features, together with the fact that this species has a highly pleiomorphic sperm head shape, are somewhat reminiscent of those of the seminiferous epithelium in humans and some other primates but not of common laboratory rodents. This species could thus be a good model for investigating irregular patterns of spermatogenesis in naturally occurring wild species of rodent. 相似文献
76.
Spontaneous pneumothorax is a recognised cause of respiratory distress in the neonatal period. Spontaneous pneumothorax occurring
during the neonatal period in siblings within a family is rare. We report a case of spontaneous pneumothorax occurring in
two siblings in the neonatal period. 相似文献
77.
Kavirajan HC 《Neurology》2005,65(2):338-9; author reply 338-9
78.
Panicker HK Janicic N Nguyen D Verbalis J 《AJNR. American journal of neuroradiology》2005,26(2):357-359
We describe a case of presumed postpartum infundibuloneurohypophysitis, which is a rare inflammatory process involving the pituitary stalk and posterior pituitary. Only one case has been previously reported in a postpartum woman. Serial MR images obtained in our patient revealed spontaneous regression of inflammation. The critical position of the inflammation leads to hormonal deficiencies, mostly involving the posterior pituitary. Treatment options include hormone replacement; the role of pharmacological steroids is controversial. 相似文献
79.
Preutthipan S Chen SH Tilly JL Kugu K Lareu RR Dharmarajan AM 《Reproductive biomedicine online》2004,9(3):264-270
To determine if nitric oxide (NO) plays a role in corpus luteum (CL) physiology by affecting progesterone secretion or luteal apoptosis, an in-vitro pseudopregnant rabbit ovarian perfusion system was used to measure the effects of an inhibitor of NO synthesis, NG-nitro-L-arginine methyl ester (L-NAME), on progesterone secretion and corpus luteal apoptosis as measured by internucleosomal DNA breakdown. Pseudopregnant rabbit ovaries perfused in vitro with L-NAME did not demonstrate any significant differences compared with control ovaries in progesterone secretion. However, apoptosis, as measured by internucleosomal breakdown, was significantly increased in L-NAME-perfused CL compared with controls. While NO does not appear to directly affect progesterone secretion, there does appear to be a role for NO in CL maintenance, or a role for inhibition of NO production in CL regression. 相似文献
80.
OBJECTIVE: To determine the association between fetal nasal bone hypoplasia and aneuploidy in women undergoing prenatal diagnosis. METHODS: A prospective cohort study involving women undergoing chorionic villus sampling and amniocentesis for an increased risk of aneuploidy. Fetal biometric and nasal bone measurements were obtained at the time of prenatal diagnosis and compared with karyotypes. Nasal bone hypoplasia was defined as nasal bone less than 2.5th percentile for the gestational age. RESULTS: A total of 632 fetuses were evaluated. Twenty-nine (4.6%) had an aneuploidy (18 trisomy 21, 5 trisomy 18, 1 Turner's syndrome, one Marker chromosome 1, 2 sex chromosome anomalies, and 2 triploidy). Nasal bone measurements were documented in 29 aneuploid fetuses. The nasal bone was either absent or hypoplastic in 12 of 29 (41%) fetuses with aneuploidy and in 8 of 18 (44%) with trisomy 21. By using receiver operating characteristics curves, the optimal threshold of nasal bone hypoplasia associated with fetal aneuploidy was a biparietal diameter/nasal bone ratio of 11 or greater. The sensitivity, specificity, and positive and negative predictive values for the detection of fetal aneuploidy were 50%, 93%, 24%, and 98%, respectively. CONCLUSION: Absent or hypoplastic nasal bone is a marker for fetal aneuploidy in a high-risk population. However, this marker needs to be evaluated by larger prospective studies in low-risk populations before adoption for clinical use. 相似文献