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71.
The potency for fertilization and successful implantation was compared between fresh and cryopreserved testicular spermatozoa obtained from the same patient with non-obstructive azoospermia. Spermatozoa cryopreserved at the outset were also evaluated. Non-obstructive azoospermic men (n = 55) underwent testicular sperm extraction (TESE); mature spermatozoa were found in 33 (60%) of them. Of 57 intracytoplasmic sperm injection (ICSI) cycles in 25 patients, 15 used fresh spermatozoa (14 patients, group 1), 24 used the excess spermatozoa cryopreserved after 'fresh' ICSI (11 couples who did not conceive in the 'fresh' cycle, group 2) and 18 cycles used cryopreserved spermatozoa at the outset (11 other patients, group 3). Fertilization, cleavage, embryo quality, implantation and take home baby rates were not significantly different in groups 1 and 2, and 6/14 couples ultimately had healthy babies (42.8% cumulative take home baby rate per TESE). In group 3, neither the fertilization rate, embryo development, pregnancy nor implantation rates per embryo transfer were significantly different from groups 1 and 2. The cumulative delivery and ongoing pregnancy rate in this group was 36. 4%. Cryopreservation did not impair the availability of motile spermatozoa for ICSI. When immotile spermatozoa were injected, however, fertilization rate decreased dramatically. Since criteria for predicting the presence of spermatozoa in the testicular tissue of patients with non-obstructive azoospermia are inadequate, it is suggested that TESE be performed prior to initiating ovarian stimulation.  相似文献   
72.

Purpose

To examine ovarian reserve following chemotherapy in women with Hodgkin’s disease.

Methods

The study included nine patients who underwent ovarian tissue cryopreservation (OTCP) prior to chemotherapy consisting of the ABVD regimen (Adriamycin, bleomycin, vinblastine, and dacarbazine) and co-treatment with gonadotropin-releasing hormone agonist (GnRH-a) (Group A), and 13 patients treated by the ABVD protocol only without GnRH-a (Group B). The average age was 25.2?±?2.7 years for the women in Group A and 31.8?±?6.8 years for those in Group B.

Results

Six months following the end of chemotherapy, the menstrual cycle resumed in all Group A patients and in four Group B patients who had amenorrhea. Eight Group B patients had regular menses during and after chemotherapy. None of the patients suffered from ovarian failure. Two Group A patients conceived in the first year after completing chemotherapy.

Conclusions

Co-treatment with GnRH-a has little effect on ovarian protection in women with Hodgkin’s disease.  相似文献   
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OBJECTIVE: To evaluate whether a combination of IUI and frozen-thawed embryo transfer (FT-ET) with ovulation induction would improve the PR in couples with unexplained infertility. DESIGN: Prospective, randomized study. SETTING: In Vitro Fertilization Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. PATIENT(s): Sixty-two patients with unexplained infertility were assigned into two groups. The study group was composed of 32 women (38 cycles) who received ovulation induction followed by IUI and FT-ET. The control group was composed of 30 women (33 cycles) who received ovulation induction followed by FT-ET. INTERVENTION(s): Clomiphene citrate (CC) and hCG, IUI, and FT-ET. MAIN OUTCOME MEASURE(s): Pregnancy rate (PR) per cycle, PR per ET. RESULT(s): In the study group, the PR per cycle and per ET were 36.8% (14 of 38) and 40.6% (13 of 32), respectively. In the control group, the PR per cycle and per ET were 12.1% (4 of 33) and 14.3% (4 of 28), respectively. Statistically significant differences were found between the two groups in the PR per cycle (P=.02) and PR per ET (P=.03). No statistically significant difference was found between the groups for the stage in which the embryos were cryopreserved, the survival cleavage rates after thawing, grading of thawed embryos, and number of embryos transferred. CONCLUSION(s): In couples with unexplained infertility, the PR may be improved by combining IUI and FT-ET with ovulation induction. Performing IUI before thawing may prevent treatment cancellation in cycles with no surviving embryos.  相似文献   
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77.
OBJECTIVES: Duchenne muscular dystrophy (DMD) is a lethal X-linked recessive disorder with an incidence of approximately 1 in 3500 males, caused by mutation in the DMD gene. About 2/3 of DMD cases are caused by gross DMD gene deletion mutations. The purpose of this study was to develop a series of single-cell multiplex-nested PCR protocols for preimplantation genetic diagnosis (PGD) of the most prevalent DMD deletions. METHODS: The protocols were developed on single blood leukocytes from normal males and females and patients with known DMD gene deletion. In the first reaction, 2 of 11 different primer sets (exons 4, 8, 12, 13, 17, 46, 47, 49, 50, 52 and intron 52) were used to allow the simultaneous amplification of different DMD loci and the SRY gender marker, in a single triplex-nested polymerase chain reaction (PCR). Aliquots of this reaction were then subjected to nested PCR in which each locus was amplified individually. Following the successful establishment of single-cell triplex-nested PCR in single leukocytes, the technique was employed in five clinical PGD cases. RESULTS: For each DMD locus, more than 50 single leukocytes from healthy controls and more than 100 single leukocytes from affected individuals with known deletions were analyzed. Amplification efficiency for each tested locus was 98-100%. The false-negative rates for each analysis taken separately was <1%. Taken together, however, the results of the triplex-nested PCR analysis had a false-negative rate of 0%. No contamination was detected in all wash-drop blanks tested. We subsequently performed 18 PGD cycles in 5 DMD carriers. A total of 156 embryos were biopsied and successfully analyzed. Of these, 39 affected embryos were detected and 50 unaffected embryos were transferred (mean = 2.9 +/- 1.1 embryos per cycle). These resulted in three biochemical pregnancies and three clinical pregnancies, all of which have culminated in the birth of normal offspring. CONCLUSION: Triplex-nested PCR using 2 of 11 DMD loci and the SRY gender marker allow PGD for >90% of DMD families with known deletions. These protocols are associated with a high amplification efficiency and accuracy.  相似文献   
78.
Rouhani FJ  Dor FJ  Cooper DK 《Transfusion》2004,44(7):1004-1012
BACKGROUND: Pigs are a potential source of red blood cells (RBCs) for transfusion into humans, but the pre‐sence of galactose‐α1,3‐galactose (Gal) epitopes on their surface, against which humans have anti‐Gal, has been perceived as a major barrier. α1,3‐Galactosyltransferase gene‐knockout pigs, which do not express Gal epitopes on RBCs (Gal–/–), have recently become available. STUDY DESIGN AND METHODS: In vitro, RBCs from Gal–/– pigs were exposed to sera from naïve humans or baboons or from baboons previously sensitized to pig antigens; immunoglobulin binding was measured by flow cytometry, and cytotoxicity, by a hemolytic assay. In vivo, relatively small numbers of Gal–/– RBCs were transfused into two nonsensitized untreated baboons. The survival of pig RBCs was detected by flow cytometry. RESULTS: In vitro, binding of immunoglobulin (Ig) M from naïve human or baboon sera was detected to Gal–/– RBCs but was significantly less than to Gal+/+ RBCs; IgG binding to Gal–/– RBCs was absent or minimal. Sera had minimal cytotoxicity to Gal–/– RBCs compared to Gal+/+ RBCs. Sensitized baboon sera demonstrated much higher IgG binding to Gal–/– RBCs and increased cytotoxicity, but again these were less than to Gal+/+ RBCs. In vivo, the transfusion of relatively small volumes of Gal–/– RBCs was followed by detection of the cells in the baboon's blood for only 5 minutes. CONCLUSION: Pig RBCs are rapidly phagocytosed from the primate circulation by a mechanism not involving anti‐Gal.  相似文献   
79.
Increased rates of thrombophilia in women with repeated IVF failures   总被引:4,自引:0,他引:4  
BACKGROUND: We investigated whether hereditary thrombophilia is more prevalent in women with recurrent IVF-embryo transfer failures. METHODS: This case-control study was conducted in an academic tertiary care hospital and compared 45 women with a history of four or more failed IVF cycles (group A) with 44 apparently healthy women matched for age and ethnic origin (group B). All participants were tested for inherited thrombophilias: mutations of prothrombin, factor V Leiden and methylene tetrahydrofolate reductase (MTHFR), and protein C, protein S and antithrombin III deficiencies. RESULTS: Excluding homozygotic MTHFR, the incidence of thrombophilia in group A, was 26.7% compared with 9.1% in group B (P = 0.003; odds ratio 2.9; 95% confidence interval 1.02-8.4). The incidence of thrombophilia in women with unexplained infertility in group A was 42.9% (9/21), compared with 18.2% in group B (P < 0.002). CONCLUSIONS: These data suggest that inherited thrombophilia may play a role in the aetiology of repeated IVF failures, particularly in the subgroup with unexplained fertility.  相似文献   
80.
The inherent ability of pediatric metaphyseal radius fractures to heal and remodel made us question the need for immediate anatomic reduction under conscious sedation. We believe that isolated closed distal radius fractures with 15 degrees of angulation and 1 cm of shortening will heal well and remodel completely without clinical or functional sequelae. Time and expense can be decreased by splinting and follow-up without the need for immediate anatomic reduction in the emergency room. In order to answer this question, we retrospectively evaluated 34 pediatric metaphyseal wrist fractures that lost position after attempted reduction and healed in their angulated or shortened position. We looked at the time to healing, time to remodeling and any residual clinical or functional deficits. We then did a comparison cost analysis with time matched patients who had complete but minimally displaced fractures of the distal radius that were treated by immediate splinting with orthopaedic follow-up. Our results showed that skeletally immature patients with open physes, isolated injuries, dorsovolar and radioulnar angulations less than 15 degrees and less than 1 cm of shortening will heal and be out of cast within an average of 6 weeks and completely remodel within an average of 7.5 months. The average time in the emergency room was 2 h less with no reduction. The cost of the emergency room visit with attempted reduction was 50% more than splinting with early referral (US dollars 536 versus US dollars 270). None of our patients had significant clinical deformities or residual functional deficits.  相似文献   
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